Source Code

These source-code files are part of a reconstructed copy of Luminary 173, the second (unflown) release of the Apollo 14 Lunar Module (LM) Apollo Guidance Computer (AGC) software.

The reconstruction began with reconstructed source code for Luminary 178. Changes between revision 173 and 178 were backed out, as described by Luminary memo 167 (revision 1). The reconstruction was verified by matching memory-bank checksums to those listed in drawing 2021152N. Note that page numbers in the reconstructed code match those for the baseline log section mentioned in each file's changelog; the page numbers for a real Luminary 173 listing would be different.

Comments from the original source code are prefixed with a single '#' symbol, whereas comments added later are prefixed by "##" or "###". Report any errors noted by creating an issue report at the Virtual AGC project's GitHub repository.

053629,000002:                                                                                                  ## Copyright:   Public domain.
053630,000003:                                                                                                  ## Filename:    TIME_OF_FREE_FALL.agc
053631,000004:                                                                                                  ## Purpose:     A section of Luminary revision 173.
053632,000005:                                                                                                  ##              It is part of the reconstructed source code for the second
053633,000006:                                                                                                  ##              (unflown) release of the flight software for the Lunar
053634,000007:                                                                                                  ##              Module's (LM) Apollo Guidance Computer (AGC) for Apollo 14.
053635,000008:                                                                                                  ##              The code has been recreated from a reconstructed copy of
053636,000009:                                                                                                  ##              Luminary 178, as well as Luminary memo 167 (revision 1).
053637,000010:                                                                                                  ##              It has been adapted such that the resulting bugger words
053638,000011:                                                                                                  ##              exactly match those specified for Luminary 173 in NASA
053639,000012:                                                                                                  ##              drawing 2021152N, which gives relatively high confidence
053640,000013:                                                                                                  ##              that the reconstruction is correct.
053641,000014:                                                                                                  ## Reference:   pp. 1257-1272
053642,000015:                                                                                                  ## Assembler:   yaYUL
053643,000016:                                                                                                  ## Contact:     Ron Burkey <info@sandroid.org>.
053644,000017:                                                                                                  ## Website:     www.ibiblio.org/apollo/index.html
053645,000018:                                                                                                  ## Mod history: 2019-09-18 MAS  Created from Luminary 178.
053646,000019: 

Page 1257

053648,000021:                                                                                                  #           THE TFF SUBROUTINES MAY BE USED IN EITHER EARTH OR MOON CENTERED COORDINATES. THE TFF ROUTINES NEVER
053649,000022:                                                                                                  #  KNOW WHICH ORIGIN APPLIES. IT IS THE USER WHO KNOWS, AND WHO SUPPLIES  RONE, VONE AND 1/SQRT(MU)  AT THE
053650,000023:                                                                                                  #  APPROPRIATE SCALE LEVEL FOR THE PROPER PRIMARY BODY.
053651,000024: 
053652,000025:                                                                                                  #           EARTH ORIGIN           POSITION      -29       METERS
053653,000026:                                                                                                  #                                  VELOCITY      -7        METERS/CENTISECOND
053654,000027:                                                                                                  #                                  1/SQRT(MU)    +17       SQRT(CS SQ/METERS CUBED)
053655,000028: 
053656,000029:                                                                                                  #           MOON ORIGIN            POSITION      -27       METERS
053657,000030:                                                                                                  #                                  VELOCITY      -5        METERS/CENTISECONDS
053658,000031:                                                                                                  #                                  1/SQRT(MU)    +14       SQRT(CS SQ/METERS CUBED)
053659,000032: 
053660,000033:                                                                                                  #  ALL DATA PROVIDED TO AND RECEIVED FROM ANY TFF SUBROUTINE WILL BE AT ONE OF THE LEVELS ABOVE. IN ALL CASES,
053661,000034:                                                                                                  #  THE FREE FALL TIME IS RETURNED IN CENTISECONDS AT (-28). PROGRAM  TFF/CONIC  WILL GENERATE VONE/RTMU  AND
053662,000035:                                                                                                  #  LEAVE IT IN  VONE' AT (+10) IF EARTH ORIGIN AND (+9) IF MOON ORIGIN.
053663,000036:                                                                                                  #           THE USER MUST STORE THE STATE VECTOR IN  RONE, VONE  AND MU IN  THE FORM 1/SQRT(MU) IN  TFF/RTMU
053664,000037:                                                                                                  #  AT THE PROPER SCALE BEFORE CALLING  TFF/CONIC. SINCE  RONE, VONE  ARE IN THE EXTENDED VERB STORAGE AREA,
053665,000038:                                                                                                  #  THE USER MUST ALSO LOCK OUT THE EXTENDED VERBS, AND RELEASE THEM WHEN FINISHED.
053666,000039:                                                                                                  #           PROGRAMS     CALC/TFF  AND  CALC/TPER  ASSUME THAT THE TERMINAL RADIUS IS LESS THAN THE PRESENT
053667,000040:                                                                                                  #  RADIUS. THIS RESTRICTION CAN BE REMOVED BY A  15 W CODING CHANGE, BUT AT PRESENT IT IS NOT DEEMED NECESSARY.
053668,000041: 
053669,000042:                                                                                                  #           THE FOLLOWING ERASABLE QUANTITIES ARE USED BY THE TFF ROUTINES, AND ARE LOCATED IN THE PUSH LIST.
053670,000043: 
053671,000044:                                                                                                  #  BELOW      E:   IS USED FOR EARTH ORIGIN SCALE
053672,000045:                                                                                                  #             M:   IS USED FOR MOON  ORIGIN SCALE
053673,000046: 
053674,000047:                                                                                                  # TFFSW          =       119D       BIT1      0 = CALCTFF        1 = CALCTPER
053675,000048: 10,2213                        TFFDELQ            =        10D                                   #             Q2-Q1              E: (-16)  M: (-15)
053676,000049: 10,2213                        RMAG1              =        12D                                   #             ABVAL(RN)  M       E: (-29)  M: (-27)
053677,000050:                                                                                                  # RPER           =       14D                  PERIGEE RADIUS M   E: (-29)  M: (-27)
053678,000051: 10,2213                        TFFQ1              =        14D                                   #             R.V / SQRT(MUE)    E: (-16)  M: (-15)
053679,000052:                                                                                                  # SDELF/2                                     SIN(THETA) /2
053680,000053: 10,2213                        CDELF/2            =        14D                                   #             COS(THETA) /2
053681,000054:                                                                                                  # RAPO           =       16D                  APOGEE RADIUS  M   E: (-29)  M: (-27)
053682,000055: 10,2213                        NRTERM             =        16D                                   #             TERMINAL RADIUS M  E: (-29+NR)
053683,000056:                                                                                                  #                                M: (-27+NR)
053684,000057: 10,2213                        RTERM              =        18D                                   #             TERMINAL RADIUS M  E: (-29)  M: (-27)
053685,000058: 10,2213                        TFFVSQ             =        20D                                   #             -(V SQUARED/MU)  1/M  E: (20)  M: (18)
053686,000059: 10,2213                        TFF1/ALF           =        22D                                   #             SEMI MAJ AXIS  M  E: (-22-2 NA)
053687,000060:                                                                                                  #                               M: (-20-2 NA)
053688,000061: 10,2213                        TFFRTALF           =        24D                                   #             SQRT(ALFA)  E: (10+NA)  M: (9+NA)
053689,000062: 10,2213                        TFFALFA            =        26D                                   #             ALFA  1/M   E: (26-NR)  M: (24-NR)
053690,000063: 10,2213                        TFFNP              =        28D                                   #             SEMI LATUS RECTUM  M  E: (-38+2 NR)
053691,000064:                                                                                                  #                                   M: (-36+2 NR)
053692,000065: 10,2213                        TFF/RTMU           =        30D                                   #             1/SQRT(MU)         E: (17)   M: (14)
053693,000066: 10,2213                        NRMAG              =        32D                                   #             PRESENT RADIUS  M  E: (-29+NR)
053694,000067:                                                                                                  #                                M: (-27+NR)
053695,000068: 10,2213                        TFFX               =        34D                                   
053696,000069: 10,2213                        TFFTEM             =        36D                                   #             TEMPORARY
053697,000070: 

Page 1258

053699,000072:                                                                                                  #                                           REGISTERS S1, S2 ARE UNTOUCHED BY ANY TFF SUBROUTINE
053700,000073:                                                                                                  #                                           INDEX REGISTERS X1, X2 ARE USED BY ALL TFF SUBROUTINES. THEY ARE ESTAB-
053701,000074:                                                                                                  #                                           LISHED IN TFF/CONIC AND MUST BE PRESERVED BETWEEN CALLS TO SUBSEQUENT
053702,000075:                                                                                                  #                                           SUBROUTINES.
053703,000076:                                                                                                  #                                           -NR                             C(X1) = NORM COUNT OF RMAG
053704,000077:                                                                                                  #                                           -NA                             C(X2)= NORM COUNT OF SQRT(ABS(ALFA))
053705,000078: 

Page 1259

053707,000080: 
053708,000081: 
053709,000082:                                                                                                  #  SUBROUTINE NAME:     TFFCONIC                                           DATE:    01.29.67
053710,000083:                                                                                                  #  MOD NO:  0                                                              LOG SECTION:    TIME OF FREE FALL
053711,000084:                                                                                                  #  MOD BY:  RR BAIRNSFATHER
053712,000085:                                                                                                  #  MOD NO:  1           MOD BY:  RR BAIRNSFATHER      DATE:  11 APR 67
053713,000086:                                                                                                  #  MOD NO:  2           MOD BY:  RR BAIRNSFATHER      DATE:  21 NOV 67     ADD MOON MU.
053714,000087:                                                                                                  #  MOD NO:  3           MOD BY:  RR BAIRNSFATHER      DATE:  21 MAR 68     ACCEPT DIFFERENT EARTH/MOON SCALES
053715,000088:                                                                                                  #  FUNCTIONAL DESCRIPTION:      THIS SUBROUTINE IS CALLED TO COMPUTE THOSE CONIC PARAMETERS REQUIRED BY THE TFF
053716,000089:                                                                                                  #           SUBROUTINES AND TO ESTABLISH THEM IN THE PUSH LIST AREA. THE PARAMETERS ARE LISTED UNDER OUTPUT.
053717,000090:                                                                                                  #           THE EQUATIONS ARE
053718,000091:                                                                                                  #                  -   -  -
053719,000092:                                                                                                  #                  H = RN*VN                                               ANGULAR MOMENTUM
053720,000093:                                                                                                  #                        - -
053721,000094:                                                                                                  #                  LCP = H.H / MU                                          SEMI LATUS RECTUM
053722,000095:                                                                                                  #                                -  -
053723,000096:                                                                                                  #                  ALFA = 2/RN - VN.VN / MU                                RECIPROCAL SEMI MAJ AXIS, SIGNED
053724,000097: 
053725,000098:                                                                                                  #           AND ALFA IS POS FOR ELLIPTIC  ORBITS
053726,000099:                                                                                                  #                        0  FOR PARABOLIC ORBITS
053727,000100:                                                                                                  #                       NEG FOR HYPERBOLIC ORBITS.
053728,000101:                                                                                                  #           SUBROUTINE ALSO COMPUTES AND SAVES  RMAG.
053729,000102:                                                                                                  #  CALLING SEQUENCE:
053730,000103:                                                                                                  #           TFFCONIC  EXPECTS CALLER TO ENTER WITH CORRECT GRAVITATIONAL CONSTANT IN MPAC, IN THE FORM
053731,000104:                                                                                                  #           1/SQRT(MU). PROGRAM WILL SAVE IN  TFF/RTMU  . THE SCALE IS DETERMINED BY WHETHER EARTH OR MOON
053732,000105:                                                                                                  #           ORIGIN IS USED.  THE CALLER MUST LOCK OUT THE EXTENDED VERBS BEFORE PROVIDING STATE VECTOR IN RONE,
053733,000106:                                                                                                  #           VONE  AT PROPER SCALE. THE EXTENDED VERBS MUST BE RESTORED WHEN THE CALLER IS FINISHED USING THE
053734,000107:                                                                                                  #           TFF ROUTINES.
053735,000108:                                                                                                  #           ENTRY POINT  TFFCONMU  EXPECTS THAT  TFF/RTMU  IS ALREADY LOADED.
053736,000109:                                                                                                  #           TO SPECIFY MU:      DLOAD  CALL                IF MU ALREADY STORED:    CALL
053737,000110:                                                                                                  #                                      YOURMU       1/RTMU   E: (17)  M: (14)              TFFCONMU
053738,000111:                                                                                                  #                                      TFFCONIC
053739,000112:                                                                                                  #           PUSHLOC = PDL+0, ARBITRARY IF LEQ 18D
053740,000113: 
053741,000114:                                                                                                  #  SUBROUTINES CALLED:  NONE
053742,000115:                                                                                                  #  NORMAL EXIT MODES:   RVQ
053743,000116:                                                                                                  #  ALARMS:  NONE
053744,000117:                                                                                                  #  OUTPUT:  THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
053745,000118:                                                                                                  #           RMAG1  E:(-29) M:(-27) M  RN, PRESENT RADIUS LENGTH.
053746,000119:                                                                                                  #           NRMAG  E: (-29+NR)     M  RMAG, NORMALIZED
053747,000120:                                                                                                  #                  M: (-27+NR)
053748,000121:                                                                                                  #           X1                     -NR, NORM COUNT
053749,000122:                                                                                                  #           TFFNP  E: (-38+2NR)    M  LCP, SEMI LATUS RECTUM, WEIGHTED BY NR.       FOR VGAMCALC
053750,000123:                                                                                                  #                  M: (-36+2NR)
053751,000124:                                                                                                  #           TFF/RTMU  E:(17)  M:(14)       1/SQRT(MU)
053752,000125:                                                                                                  #           TFFVSQ E:(20)  M:(18)  1/M   -(V SQ/MU): PRESENT VELOCITY,NORMLIZED.    FOR VGAMCALC
053753,000126:                                                                                                  #           TFFALFA  E: (26-NR)    1/M   ALFA, WEIGHTED BY NR
053754,000127:                                                                                                  #                    M: (24-NR)
053755,000128:                                                                                                  #           TFFRTALF  E: (10+NA)   SQRT(ALFA), NORMALIZED
053756,000129:                                                                                                  #                     M: (9+NA)

Page 1260

053758,000131:                                                                                                  #           X2                     -NA, NORM COUNT
053759,000132:                                                                                                  #           TFF1/ALF  E: (-22-2NA) SIGNED SEMI MAJ AXIS, WEIGHTED BY NA
053760,000133:                                                                                                  #                     M: (-20-2NA)
053761,000134:                                                                                                  #           PUSHLOC AT PDL+0
053762,000135:                                                                                                  #           THE FOLLOWING  IS STORED IN GENERAL ERASABLE
053763,000136:                                                                                                  #           VONE'  E:(10)  M:(9)   V/RT(MU), NORMALIZED VELOCITY
053764,000137:                                                                                                  #  ERASABLE INITIALIZATION REQUIRED:
053765,000138:                                                                                                  #           RONE   E:(-29)  M:(-27)  M      STATE VECTOR                   LEFT BY CALLER
053766,000139:                                                                                                  #           VONE   E:(-7)   M:(-5)   M/CS   STATE VECTOR                   LEFT BY CALLER
053767,000140:                                                                                                  #           TFF/RTMU  E:(17)  M:(14)      1/RT(CS SQ/M CUBE)               IF ENTER VIA  TFFCONMU.
053768,000141:                                                                                                  #  DEBRIS:  QPRET,    PDL+0 ... PDL+3
053769,000142: 
053770,000143: 
053771,000144: 33,3530                                           BANK     33                                    
053772,000145: 27,2000                                           SETLOC   TOF-FF                                
053773,000146: 27,2000                                           BANK                                           
053774,000147: 
053775,000148: 27,3357                                           COUNT*   $$/TFF                                
053776,000149: 
053777,000150: 27,3357           00037        TFFCONIC           STORE    TFF/RTMU                              #  1/SQRT(MU)       E: (17)   M: (14)
053778,000151: 
053779,000152: 27,3360           53575        TFFCONMU           VLOAD    UNIT                                  #  COME HERE WITH TFFRTMU LOADED.
053780,000153: 27,3361           02207                                    RONE                                  #  SAVED RN.  M     E: (-29)  M: (-27)
053781,000154: 27,3362           77725                           PDDL                                           #  UR/2 TO PDL+0, +5
053782,000155: 27,3363           00045                                    36D                                   #  MAGNITUDE
053783,000156: 27,3364           00015                           STORE    RMAG1                                 #  M    E: (-29)   M: (-27)
053784,000157: 
053785,000158: 27,3365           77701                           NORM                                           
053786,000159: 27,3366           00047                                    X1                                    #  -NR
053787,000160: 27,3367           24041                           STOVL    NRMAG                                 #  RMAG  M   E: (-29+NR)  M: (-27+NR)
053788,000161: 27,3370           02215                                    VONE                                  #  SAVED VN.  M/CS   E: (-7)   M: (-5)
053789,000162: 27,3371           77761                           VXSC                                           
053790,000163: 27,3372           00037                                    TFF/RTMU                              #  E: (17)   M: (14)
053791,000164: 27,3373           02170                           STORE    VONE'                                 #  VN/SQRT(MU)   E: (10)   M: (9)
053792,000165: 
053793,000166: 27,3374           47361                           VXSC     VXV                                   
053794,000167: 27,3375           00041                                    NRMAG                                 #  E: (-29+NR)  M: (-27+NR)
053795,000168:                                                                                                  #  UR/2 FROM PDL
053796,000169: 27,3376           47572                           VSL1     VSQ                                   #  BEFORE:  E:(-19+NR)  M:(-18+NR)
053797,000170: 27,3377           14035                           STODL    TFFNP                                 #  LC P  M   E:(-38+2NR)  M:(-36+2NR)
053798,000171:                                                                                                  #  SAVE ALSO FOR VGAMCALC
053799,000172: 27,3400           06510                                    TFF1/4                                
053800,000173: 27,3401           63271                           DDV      PDVL                                  #  (2/RMAG)  1/M   E:(26-NR)   M:(24-NR)
053801,000174: 27,3402           00041                                    NRMAG                                 #  RMAG  M   E:(-29+NR)  M:(-27+NR)
053802,000175: 27,3403           02170                                    VONE'                                 #  SAVED VN.   E: (10)   M: (9)
053803,000176: 27,3404           57436                           VSQ      DCOMP                                 #  KEEP MPAC+2 HONEST FOR SQRT.
053804,000177: 27,3405           00025                           STORE    TFFVSQ                                #  -(V SQ/MU)   E:(20)   M:(18)
053805,000178:                                                                                                  #  SAVE FOR VGAMCALC
053806,000179: 27,3406           43257                           SR*      DAD                                   

Page 1261

053808,000181: 27,3407           20573                                    0          -6,1                       #  GET -VSQ/MU   E:(26-NR)   M:(24-NR)
053809,000182: 27,3410           77626                           STADR                                          
053810,000183:                                                                                                  #  2/RMAG   FROM PDL+2
053811,000184: 27,3411           77744                           STORE    TFFALFA                               #  ALFA  1/M   E:(26-NR)   M:(24-NR)
053812,000185: 27,3412           41457                           SL*      PUSH                                  #  TEMP SAVE ALFA    E:(20)   M:(18)
053813,000186: 27,3413           20173                                    0          -6,1                       
053814,000187: 27,3414           75446                           ABS      SQRT                                  #  E:(10)   M:(9)
053815,000188: 27,3415           77701                           NORM                                           
053816,000189: 27,3416           00050                                    X2                                    #  X2 = -NA
053817,000190: 27,3417           00031                           STORE    TFFRTALF                              #  SQRT( ABS(ALFA) )  E:(10+NA)   M:(9+NA)
053818,000191: 27,3420           75316                           DSQ      SIGN                                  #  NOT SO ACCURATE, BUT OK
053819,000192:                                                                                                  #  ALFA FROM PDL+2   E:(20)   M:(18)
053820,000193: 27,3421           55254                           BZE      BDDV                                  #  SET 1/ALFA =0, TO SHOW SMALL ALFA
053821,000194: 27,3422           57424                                    +2                                    
053822,000195: 27,3423           06510                                    TFF1/4                                
053823,000196: 27,3424           00027                 +2        STORE    TFF1/ALF                              #  1/ALFA   E:(-22-2 NA)   M:(-20-2 NA)
053824,000197: 27,3425           77616        DUMPCNIC           RVQ                                            
053825,000198: 
053826,000199:                                                                                                  #                          39 W
053827,000200: 

Page 1262

053829,000202:                                                                                                  #  SUBROUTINE NAME:     TFFRP/RA                                           DATE:  01.17.67
053830,000203:                                                                                                  #  MOD NO:  0                                                              LOG SECTION:    TIME OF FREE FALL
053831,000204:                                                                                                  #  MOD BY:  RR BAIRNSFATHER
053832,000205:                                                                                                  #  MOD NO:  1           MOD BY:  RR BAIRNSFATHER      DATE:  11 APR 67
053833,000206:                                                                                                  #  MOD NO:  2           MOD BY:  RR BAIRNSFATHER      DATE:  21 MAR 68     ACCEPT DIFFERENT EARTH/MOON SCALES
053834,000207:                                                                                                  #                                                                          ALSO IMPROVE ACCURACY OF RAPO.
053835,000208:                                                                                                  #  FUNCTIONAL DESCRIPTION:         USED BY CALCTPER AND TFF DISPLAYS TO CALCULATE PERIGEE RADIUS AND ALSO
053836,000209:                                                                                                  #           APOGEE RADIUS FOR A GENERAL CONIC.
053837,000210:                                                                                                  #           PROGRAM GIVES PERIGEE RADIUS AS               APOGEE RADIUS IS GIVEN BY
053838,000211:                                                                                                  #                  RP = P /(1+E)                                 RA = (1+E) / ALFA
053839,000212:                                                                                                  #           WHERE   2
053840,000213:                                                                                                  #                  E  = 1 - P ALFA
053841,000214:                                                                                                  #           IF RA IS NEGATIVE OR SHOWS DIVIDE OVERFLOW, THEN RA = POSMAX BECAUSE
053842,000215:                                                                                                  #                  1. APOGEE RADIUS IS NOT MEANINGFUL FOR HYPERBOLA
053843,000216:                                                                                                  #                  2. APOGEE RADIUS IS NOT DEFINED FOR PARABOLA
053844,000217:                                                                                                  #                  3. APOGEE RADIUS EXCEEDS THE SCALING FOR ELLIPSE.
053845,000218:                                                                                                  #           THIS SUBROUTINE REQUIRES THE SIGNED  RECIPROCAL SEMI MAJ AXIS,  ALFA,  AND SEMI LATUS RECTUM AS DATA.
053846,000219:                                                                                                  #  CALLING SEQUENCE:  CALL
053847,000220:                                                                                                  #                            TFFRP/RA
053848,000221:                                                                                                  #           PUSHLOC = PDL+0, ARBITRARY IF LEQ 10D
053849,000222:                                                                                                  #           C(MPAC) UNSPECIFIED
053850,000223: 
053851,000224:                                                                                                  #  SUBROUTINES CALLED:  NONE
053852,000225:                                                                                                  #  NORMAL EXIT MODE:    RVQ
053853,000226:                                                                                                  #           IF ELLIPSE, WITHIN NORMAL SCALING, RAPO IS CORRECT.
053854,000227:                                                                                                  #           OTHERWISE, RAPO = POSMAX.
053855,000228:                                                                                                  #  ALARMS:  NONE
053856,000229:                                                                                                  #  OUTPUT:  STORED IN PUSH LIST AREA. SCALE OF OUTPUT AGREES WITH DATA SUPPLIED TO  TFF/CONIC.
053857,000230:                                                                                                  #           RPER   E:(-29)  M:(-27)  M     PERIGEE RADIUS                  DESTROYED BY CALCTFF/CALCTPER, TFFTRIG.
053858,000231:                                                                                                  #           RAPO   E:(-29)  M:(-27)  M     APOGEE  RADIUS                  WILL BE DESTROYED BY CALCTFF/CALCTPER
053859,000232:                                                                                                  #           PUSHLOC AT PDL+0
053860,000233:                                                                                                  #  ERASABLE INITIALIZATION REQUIRED:
053861,000234:                                                                                                  #           TFFALFA E:(26-NR)      M   1/SEMI MAJ AXIS                     LEFT BY TFFCONIC
053862,000235:                                                                                                  #                   M:(24-NR)
053863,000236:                                                                                                  #           TFFNP  E: (-38+2NR)    M  LC P, SEMI LATUS RECTUM              LEFT BY TFFCONIC
053864,000237:                                                                                                  #                  M: (-36+2NR)
053865,000238:                                                                                                  #           X1                     -NR, NORM COUNT OF RMAG                 LEFT BY TFFCONIC
053866,000239:                                                                                                  #           X2                     -NA, NORM COUNT OF ALFA                 LEFT BY TFFCONIC
053867,000240:                                                                                                  #  DEBRIS:  QPRET,    PDL+0 ... PDL+1
053868,000241: 

Page 1263

053870,000243: 27,3426                        RAPO               =        16D                                   #  APOGEE RADIUS  M  E:(-29)  M:(-27)
053871,000244: 27,3426                        RPER               =        14D                                   #  PERIGEE RADIUS  M  E:(-29)  M:(-27)
053872,000245: 
053873,000246: 27,3426           41345        TFFRP/RA           DLOAD    DMP                                   
053874,000247: 27,3427           00033                                    TFFALFA                               #  ALFA  1/M  E:(26-NR)   M:(24-NR)
053875,000248: 27,3430           00035                                    TFFNP                                 #  LC P  M   E:(-38+2NR)   M:(-36+2NR)
053876,000249: 27,3431           57457                           SR*      DCOMP                                 #  ALFA P (-12+NR)
053877,000250: 27,3432           20571                                    0          -8D,1                      #  ALFA P  (-4)
053878,000251: 27,3433           51415                           DAD      ABS                                   #  (DCOMP GIVES VALID TP RESULT FOR SQRT)
053879,000252:                                                                                                  #  (ABS PROTECTS SQRT IF E IS VERY NEAR 0)
053880,000253: 27,3434           17764                                    DP2(-4)                               
053881,000254: 27,3435           43366                           SQRT     DAD                                   #  E SQ = (1- P ALFA)   (-4)
053882,000255: 27,3436           06510                                    TFF1/4                                
053883,000256: 27,3437           55206                           PUSH     BDDV                                  #  (1+E)  (-2)  TO PDL+0
053884,000257: 27,3440           00035                                    TFFNP                                 #  LCP  M E:(-38+2NR)   M:(-36+2NR)
053885,000258: 27,3441           53657                           SR*      SR*                                   #  (DOES SR THEN SL TO AVOID OVFL)
053886,000259: 27,3442           20601                                    0,1                                   #  X1=-NR
053887,000260: 27,3443           20572                                    0          -7,1                       #  (EFFECTIVE SL)
053888,000261: 27,3444           14017                           STODL    RPER                                  #  PERIGEE RADIUS  M   E:(-29)   M:(-27)
053889,000262:                                                                                                  #  (1+E)  (-2)   FROM PDL+0
053890,000263: 27,3445           41005                           DMP      BOVB                                  
053891,000264: 27,3446           00027                                    TFF1/ALF                              #  E:(-22-2NA)  M:(-20-2NA)
053892,000265: 27,3447           57752                                    TCDANZIG                              #  CLEAR OVFIND, IF ON.
053893,000266: 27,3450           53654                           BZE      SL*                                   
053894,000267: 27,3451           57460                                    MAXRA                                 #  SET POSMAX, IF ALFA=0
053895,000268: 27,3452           57603                                    0          -5,2                       #  -5+NA
053896,000269: 27,3453           40057                           SL*      BOV                                   
053897,000270: 27,3454           57576                                    0,2                                   
053898,000271: 27,3455           57460                                    MAXRA                                 #  SET POSMAX IF OVFL.
053899,000272: 27,3456           77644                           BPL                                            #  CONTINUE WITH VALID RAPO.
053900,000273: 27,3457           57462                                    +3                                    
053901,000274: 27,3460           77745        MAXRA              DLOAD                                          #  RAPO CALC IS NOT VALID. SET RAPO =
053902,000275: 27,3461           17770                                    NEARONE                               #  POSMAX AS A TAG.
053903,000276: 27,3462           00021                 +3        STORE    RAPO                                  #  APOGEE RADIUS  M   E:(-29)   M:(-27)
053904,000277: 27,3463           77616        DUMPRPRA           RVQ                                            
053905,000278: 
053906,000279:                                                                                                  #                          30 W
053907,000280: 

Page 1264

053909,000282:                                                                                                  #  SUBROUTINE NAME:     CALCTPER  /  CALCTFF                               DATE:    01.29.67
053910,000283:                                                                                                  #  MOD NO:  0                                                              LOG SECTION:    TIME OF FREE FALL
053911,000284:                                                                                                  #  MOD BY:  RR BAIRNSFATHER
053912,000285:                                                                                                  #  MOD NO:  1           MOD BY:  RR BAIRNSFATHER      DATE:  21 MAR 67
053913,000286:                                                                                                  #  MOD NO:  2           MOD BY:  RR BAIRNSFATHER      DATE:  14 APR 67
053914,000287:                                                                                                  #  MOD NO:  3           MOD BY:  RR BAIRNSFATHER      DATE:  8JUL 67       NEAR EARTH MUE AND NEG TFF (GONEPAST)
053915,000288:                                                                                                  #  MOD NO:  4           MOD BY:  RR BAIRNSFATHER      DATE:  21 NOV 67     ADD VARIABLE MU.
053916,000289:                                                                                                  #  MOD NO:  5           MOD BY:  RR BAIRNSFATHER      DATE:  21 MAR 68     ACCEPT DIFFERENT EARTH/MOON SCALES
053917,000290:                                                                                                  #  FUNCTIONAL DESCRIPTION:      PROGRAM CALCULATES THE FREE-FALL TIME OF FLIGHT FROM PRESENT POSITION  RN  AND
053918,000291:                                                                                                  #           VELOCITY  VN  TO A RADIUS LENGTH SPECIFIED BY  RTERM  , SUPPLIED BY THE USER. THE POSITION VECTOR
053919,000292:                                                                                                  #           RN  MAY BE ON EITHER SIDE OF THE CONIC, BUT  RTERM  IS CONSIDERED ON THE INBOUND SIDE.
053920,000293:                                                                                                  #           THE EQUATIONS ARE
053921,000294: 
053922,000295:                                                                                                  #                  Q2 = -SQRT(RTERM (2-RTERM ALFA) - LCP)    (INBOUND SIDE))        LEQ +- LCE/SQRT(ALFA)
053923,000296:                                                                                                  #                       -  -
053924,000297:                                                                                                  #                  Q1 = RN.VN / SQRT(MU)                                            LEQ +- LCE/SQRT(ALFA)
053925,000298: 
053926,000299:                                                                                                  #                  Z = NUM / DEN                                                    LEQ +- 1/SQRT(ALFA)
053927,000300: 
053928,000301:                                                                                                  #           WHERE, IF INBOUND
053929,000302:                                                                                                  #                  NUM = RTERM - RN                                                 LEQ +- 2 LCE/ALFA
053930,000303:                                                                                                  #                  DEN = Q2+Q1                                                      LEQ +- 2 LCE/SQRT(ALFA)
053931,000304: 
053932,000305:                                                                                                  #           AND, IF OUTBOUND
053933,000306:                                                                                                  #                  NUM = Q2-Q1                                                      LEQ +- 2 LCE/SQRT(ALFA)
053934,000307:                                                                                                  #                  DEN = 2 - ALFA (RTERM + RN) .                                    LEQ +- 2 LCE
053935,000308: 
053936,000309:                                                                                                  #           IF     ALFA ZZ  <  1.0               (FOR ALL CONICS EXCEPT ELLIPSES HAVING ABS(DEL ECC ANOM) G 90 DEG)
053937,000310: 
053938,000311:                                                                                                  #           THEN   X = ALFA Z Z
053939,000312:                                                                                                  #           AND    TFF = (RTERM +RN -2 ZZ T(X) ) Z/SQRT(MU)
053940,000313: 
053941,000314:                                                                                                  #                  EXCEPT IF ALFA PNZ, AND IF TFF NEG,
053942,000315:                                                                                                  #                  THEN   TFF = 2 PI /(ALFA SQRT(ALFA)) + TFF
053943,000316: 
053944,000317:                                                                                                  #           OR IF  ALFA ZZ  GEQ  1.0             (FOR ELLIPSES HAVING ABS(DEL ECC ANOM) GEQ 90 DEG)
053945,000318: 
053946,000319:                                                                                                  #           THEN   X = 1/ALFA Z Z
053947,000320:                                                                                                  #           AND    TFF = (PI/SQRT(ALFA) -Q2 +Q1 +2(X T(X) -1) /ALFA Z) /ALFA SQRT(MU)
053948,000321: 
053949,000322:                                                                                                  #           WHERE  T(X) IS A POLYNOMIAL APPROXIMATION TO THE SERIES
053950,000323:                                                                                                  #                             2     3                        2
053951,000324:                                                                                                  #                  1/3 -X/5 +X /7 -X /9 ...                (X   <  1.0)
053952,000325: 
053953,000326:                                                                                                  #  CALLING SEQUENCE:  TIME TO RTERM                           TIME TO PERIGEE
053954,000327:                                                                                                  #                     CALL                                    CALL
053955,000328:                                                                                                  #                            CALCTFF                                 CALCTPER
053956,000329:                                                                                                  #                     C(MPAC) = TERMNL RAD  M                 C(MPAC) = PERIGEE RAD  M
053957,000330:                                                                                                  #           FOR EITHER,   E: (-29)    M: (-27)
053958,000331:                                                                                                  #           FOR EITHER, PUSHLOC = PDL+0, ARBITRARY IF LEQ 8D.
053959,000332: 

Page 1265

053961,000334:                                                                                                  #  SUBROUTINES CALLED:  T(X),  VIA RTB
053962,000335:                                                                                                  #  NORMAL EXIT MODE:  RVQ
053963,000336:                                                                                                  #           HOWEVER, PROGRAM EXITS WITH ONE OF THE FOLLOWING VALUES FOR TFF (-28) CS  IN MPAC. USER MUST STORE.
053964,000337:                                                                                                  #                  A.  TFF= FLIGHT TIME. NORMAL CASE FOR POSITIVE FLIGHT TIME LESS THAN ONE ORBITAL PERIOD.
053965,000338:                                                                                                  #                  B.  (THIS OPTION IS NO LONGER USED.)
053966,000339:                                                                                                  #                  C.  TFF = POSMAX.  THIS INDICATES THAT THE CONIC FROM THE PRESENT POSITION WILL NOT RETURN TO
053967,000340:                                                                                                  #                      THE SPECIFIED ALTITUDE.  ALSO INDICATES OUTBOUND PARABOLA OR HYPERBOLA.
053968,000341:                                                                                                  #  OUTPUT:  C(MPAC)  (-28)  CS     TIME OF FLIGHT, OR TIME TO PERIGEE
053969,000342:                                                                                                  #           TFFX    (0)            X,                                      LEFT FOR ENTRY DISPLAY TFF ROUTINES
053970,000343:                                                                                                  #           NRTERM  E: (-29+NR)    M  RTERM, WEIGHTED BY NR                LEFT FOR ENTRY DISPLAY TFF ROUTINES
053971,000344:                                                                                                  #                   M: (-27+NR)
053972,000345:                                                                                                  #           TFFTEM  E: (-59+2NR)   LCP Z Z SGN(SDELF)                      LEFT FOR ENTRY DISPLAY TFF ROUTINES
053973,000346:                                                                                                  #                   M: (-55+2NR)   LCP /ALFA SGN(SDELF)                    LEFT FOR ENTRY DISPLAY TFF ROUTINES
053974,000347:                                                                                                  #           NOTE:  TFFTEM = PDL 36D AND WILL BE DESTROYED BY .:UNIT:.
053975,000348:                                                                                                  #           RMAG1  E:(-29)  M:(-27)  PDL 12 NOT TOUCHED.
053976,000349:                                                                                                  #           TFFQ1  E:(-16)  M:(-15)  PDL 14D
053977,000350:                                                                                                  #           TFFDELQ E:(-16) M:(-15)  PDL 10D
053978,000351:                                                                                                  #           PUSHLOC AT PDL+0
053979,000352:                                                                                                  #  ERASABLE INITIALIZATION REQUIRED:
053980,000353:                                                                                                  #           RONE   E:(-29)  M:(-27)  M   STATE VECTOR                      LEFT BY USER
053981,000354:                                                                                                  #           VONE'  E:(+10)  M:(+9)   VN/SQRT(MU)                           LEFT BY TFF/CONIC
053982,000355:                                                                                                  #           RMAG1  E:(-29)  M:(-27)  PRESENT RADIUS,  M                    LEFT BY TFFCONIC
053983,000356:                                                                                                  #           C(MPAC)E:(-29)  M:(-27)  RTERM, TERMINAL RADIUS LENGTH, M      LEFT BY USER
053984,000357: 
053985,000358:                                                                                                  #           THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
053986,000359:                                                                                                  #           TFF/RTMU  E:(17)  M:(14)  1/SQRT(MU)                           LEFT BY TFFCONIC.
053987,000360:                                                                                                  #           NRMAG  E: (-29+NR)  M  RMAG, NORMALIZED                        LEFT BY TFFCONIC
053988,000361:                                                                                                  #                  M: (-27+NR)
053989,000362:                                                                                                  #           X1                     -NR, NORM COUNT                         LEFT BY TFFCONIC
053990,000363:                                                                                                  #           TFFNP  E: (-38+2NR)  M   LCP, SEMI LATUS RECTUM, WEIGHT  NR    LEFT BY TFFCONIC
053991,000364:                                                                                                  #                  M: (-36+2NR)
053992,000365:                                                                                                  #           TFFALFA  E: (26-NR)    1/M  ALFA, WEIGHT  NR                   LEFT BY TFFCONIC
053993,000366:                                                                                                  #                    M: (24-NR)
053994,000367:                                                                                                  #           TFFRTALF  E:(10+NA)    SQRT(ALFA), NORMALIZED                  LEFT BY TFFCONIC
053995,000368:                                                                                                  #                     M:(9+NA)
053996,000369:                                                                                                  #           X2                     -NA, NORM COUNT                         LEFT BY TFFCONIC
053997,000370:                                                                                                  #           TFF1/ALF  E: (-22-2NA)  SIGNED SEMIMAJ AXIS, WEIGHTED BY NA    LEFT BY TFFCONIC
053998,000371:                                                                                                  #                     M: (-20-2NA)
053999,000372:                                                                                                  #  DEBRIS:  QPRET,   PDL+0 ... PDL+3
054000,000373:                                                                                                  #           RTERM  E:(-29)  M:(-27)  RTERM, TERMINAL RADIUS LENGTH
054001,000374:                                                                                                  #           RAPO   E:(-29)  M:(-27)  PDL 16D  (=NRTERM)
054002,000375:                                                                                                  #           RPER   E:(-29)  M:(-27)  PDL 14D   (=TFFQ1)
054003,000376: 

Page 1266

054005,000378: 27,3464           77614        CALCTPER           SETGO                                          #  ENTER WITH RPER  IN MPAC
054006,000379: 27,3465           03436                                    TFFSW                                 
054007,000380: 27,3466           57471                                    +3                                    
054008,000381: 27,3467           77614        CALCTFF            CLEAR                                          #  ENTER WITH RTERM IN MPAC
054009,000382: 27,3470           03676                                    TFFSW                                 
054010,000383: 27,3471           00023                 +3        STORE    RTERM                                 #  E: (-29)  M: (-27)
054011,000384: 27,3472           77657                           SL*                                            
054012,000385: 27,3473           20201                                    0,1                                   #  X1=-NR
054013,000386: 27,3474           00021                           STORE    NRTERM                                #  RTERM  E: (-29+NR)  M: (-27+NR)
054014,000387: 27,3475           44205                           DMP      BDSU                                  
054015,000388: 27,3476           00033                                    TFFALFA                               #  ALFA  E: (26-NR)  M: (24-NR)
054016,000389: 27,3477           06510                                    TFF1/4                                
054017,000390: 27,3500           41206                           PUSH     DMP                                   #  (2-ALFA RTERM)  (-3)  TO PDL+0
054018,000391: 27,3501           00021                                    NRTERM                                #  E: (-29+NR)  M: (-27+NR)
054019,000392: 27,3502           53725                           PDDL     SR*                                   #  RTERM(2-ALFA RTERM) TO PDL+2
054020,000393:                                                                                                  #  E: (-32+NR)   M: (-30+NR)
054021,000394: 27,3503           00035                                    TFFNP                                 #  LC P  E:(-38+2NR)  M:(-36+2NR)
054022,000395: 27,3504           20573                                    0          -6,1                       #  X1 = -NR
054023,000396: 27,3505           43276                           DCOMP    DAD                                   #  DUE TO SHIFTS, KEEP PRECISION FOR SQRT
054024,000397:                                                                                                  #  RTERM(2-ALFA RTERM) FROM PDL+2
054025,000398:                                                                                                  #  E: (-32+NR)  M: (-30+NR)
054026,000399: 27,3506           77657                           SR*                                            #  LEAVE  E: (-32)  M: (-30)
054027,000400: 27,3507           20601                                    0,1                                   #  X1 = -NR
054028,000401: 27,3510           71214                           BOFF     DLOAD                                 #  CHECK TFF / TPER SWITCH
054029,000402: 27,3511           03756                                    TFFSW                                 
054030,000403: 27,3512           57514                                    +2                                    #  IF TFF, CONTINUE
054031,000404: 27,3513           06520                                    TFFZEROS                              #  IF TPER, SET Q2 = 0
054032,000405: 27,3514           75440                 +2        BMN      SQRT                                  #  E: (-16)  M: (-15)
054033,000406: 
054034,000407: 27,3515           57647                                    MAXTFF1                               #  NO FREE FALL CONIC TO RTERM FROM HERE
054035,000408:                                                                                                  #  RESET PDL, SET TFF=POSMAX, AND EXIT.
054036,000409: 
054037,000410: 27,3516           41076                           DCOMP    BOVB                                  #  RT IS ON INBOUND SIDE.  ASSURE OVFIND=0
054038,000411: 27,3517           57752                                    TCDANZIG                              #  ANY PORT IN A STORM.
054039,000412: 27,3520           24045                           STOVL    TFFTEM                                #  Q2   E: (-16)  M: (-15)
054040,000413: 27,3521           02170                                    VONE'                                 #  VN/SQRT(MU) E: (10)  M: (9)
054041,000414: 27,3522           52441                           DOT      SL3                                   
054042,000415: 27,3523           02207                                    RONE                                  #  SAVED RN.  E: (-29)  M: (-27)
054043,000416: 27,3524           00017                           STORE    TFFQ1                                 #  Q1, SAVE FOR GONEPAST TEST.
054044,000417:                                                                                                  #  E: (-16)  M: (-15)
054045,000418: 27,3525           44240                           BMN      BDSU                                  
054046,000419: 27,3526           57547                                    INBOUND                               #  USE ALTERNATE Z
054047,000420: 27,3527           00045                                    TFFTEM                                #  Q2  E: (-16)  M: (-15)
054048,000421: 
054049,000422:                                                                                                  #                                          OUTBOUND Z CALC CONTINUES HERE
054050,000423: 
054051,000424: 27,3530           14043                           STODL    TFFX                                  #  NUM=Q2-Q1  E: (-16)  M: (-15)
054052,000425: 27,3531           00033                                    TFFALFA                               #  ALFA  E: (26-NR)  M: (24-NR)
054053,000426: 27,3532           44205                           DMP      BDSU                                  

Page 1267

054055,000428: 27,3533           00041                                    NRMAG                                 #  RMAG  E: (-29+NR)  M: (-27+NR)
054056,000429:                                                                                                  #  (2-RTERM ALFA)  (-3) FROM PDL+0
054057,000430: 27,3534           51406        SAVEDEN            PUSH     ABS                                   #  DEN TO PDL+0  E: (-3) OR (-16)
054058,000431:                                                                                                  #                M: (-3) OR (-15)
054059,000432: 27,3535           40015                           DAD      BOV                                   #  INDETERMINANCY TEST
054060,000433: 27,3536           17756                                    LIM(-22)                              #  =1.0-B(-22)
054061,000434: 27,3537           57560                                    TFFXTEST                              #  GO IF DEN >/= B(-22)
054062,000435: 27,3540           65345                           DLOAD    PDDL                                  #  SET DEN=0  OTHERWISE
054063,000436: 27,3541           06520                                    TFFZEROS                              
054064,000437:                                                                                                  #  XCH ZERO WITH PDL+0
054065,000438: 27,3542           57545                           DLOAD    DCOMP                                 
054066,000439: 27,3543           00033                                    TFFALFA                               #  ALFA  E: (26-NR)  M: (24-NR)
054067,000440: 27,3544           71240                           BMN      DLOAD                                 #  FOR TPER: Z INDET AT DELE/2=0 AND 90.
054068,000441: 27,3545           57654                                    TFFEL1                                #  ASSUME 90, AND LEAVE 0 IN PDL: 1/Z=D/N
054069,000442: 
054070,000443:                                                                                                  #  Z INDET. AT PERIGEE FOR PARAB OR HYPERB.
054071,000444: 27,3546           77616        DUMPTFF1           RVQ                                            #  RETURN  TFF =0
054072,000445: 
054073,000446:                                                                                                  #                                          INBOUND Z CALC CONTINUES HERE
054074,000447: 27,3547           77745        INBOUND            DLOAD                                          #  RESET PDL+0
054075,000448: 27,3550           45345                           DLOAD    DSU                                   #  ALTERNATE Z CALC
054076,000449: 27,3551           00023                                    RTERM                                 #  E: (-29)  M: (-27)
054077,000450: 27,3552           00015                                    RMAG1                                 #  E: (-29)  M: (-27)
054078,000451: 27,3553           14043                           STODL    TFFX                                  #  NUM=RTERM-RN  E: (-29)  M: (-27)
054079,000452: 27,3554           00045                                    TFFTEM                                #  Q2  E: (-16)  M: (-15)
054080,000453: 27,3555           52015                           DAD      GOTO                                  
054081,000454: 27,3556           00017                                    TFFQ1                                 #  Q1  E: (-16)  M: (-15)
054082,000455: 27,3557           57534                                    SAVEDEN                               #  DEN = Q2+Q1   E: (-16)  M: (-15)
054083,000456: 
054084,000457: 27,3560           65215        TFFXTEST           DAD      PDDL                                  #   (ABS(DEN) TO PDL+2))  E: (-3) OR (-16)
054085,000458:                                                                                                  #                         M: (-3) OR (-15)
054086,000459: 27,3561           17760                                    DP(-22)                               #  RESTORE ABS(DEN) TO MPAC
054087,000460: 27,3562           00043                                    TFFX                                  #  NUM E:(-16) OR (-29)  M:(-15) OR (-27)
054088,000461: 27,3563           53605                           DMP      SR*                                   
054089,000462: 27,3564           00031                                    TFFRTALF                              #  SQRT(ALFA)  E: (10+NA)  M: (9+NA)
054090,000463: 27,3565           57201                                    0          -3,2                       #  X2=-NA
054091,000464: 27,3566           77671                           DDV                                            #  C(MPAC) =NUM SQRT(ALFA)  E:(-3) OR (-16)
054092,000465:                                                                                                  #                           M:(-3) OR (-15)
054093,000466:                                                                                                  #  ABS(DEN) FROM PDL+2  E:(-3) OR (-16)
054094,000467:                                                                                                  #                       M:(-3) OR (-15)
054095,000468: 27,3567           40145                           DLOAD    BOV                                   #  (THE DLOAD IS SHARED WITH TFFELL)
054096,000469: 27,3570           00043                                    TFFX                                  #  NUM  E: (-16) OR (-29)  M:(-15) OR (-27)
054097,000470: 27,3571           57652                                    TFFELL                                #  USE EQN FOR DELE GEQ 90, LEQ -90
054098,000471: 
054099,000472:                                                                                                  #                                          OTHERWISE, CONTINUE FOR GENERAL CONIC FOR TFF EQN
054100,000473: 
054101,000474: 27,3572           45471                           DDV      STADR                                 
054102,000475:                                                                                                  #  DEN FROM PDL+0   E: (-3) OR (-16)
054103,000476:                                                                                                  #                   M: (-3) OR (-15)
054104,000477: 27,3573           77732                           STORE    TFFTEM                                #  Z  SAVE FOR SIGN OF SDELF.

Page 1268

054106,000479:                                                                                                  #  E: (-13)  M: (-12)
054107,000480: 27,3574           63406                           PUSH     DSQ                                   #  Z TO PDL+0
054108,000481: 27,3575           41206                           PUSH     DMP                                   #  Z SQ TO PDL+2  E: (-26)  M: (-24)
054109,000482: 27,3576           00035                                    TFFNP                                 #  LC P  E: (-38+2NR)  M: (-36+2NR)
054110,000483: 27,3577           75261                           SL       SIGN                                  
054111,000484: 27,3600           20206                                    5                                     
054112,000485: 27,3601           00045                                    TFFTEM                                #  AFFIX SIGN FOR SDELF (ENTRY DISPLAY)
054113,000486: 27,3602           14045                           STODL    TFFTEM                                #  P ZSQ  E: (-59+2NR)  M: (-55+2NR)
054114,000487:                                                                                                  #  (ARG IS USED IN TFF/TRIG)
054115,000488:                                                                                                  #  ZSQ FROM PDL+2   E: (-26)  M: (-24)
054116,000489: 27,3603           41206                           PUSH     DMP                                   #  RESTORE PUSH LOC
054117,000490: 27,3604           00033                                    TFFALFA                               #  ALFA  E: (26-NR)  M: (24-NR)
054118,000491: 27,3605           77657                           SL*                                            
054119,000492: 27,3606           20201                                    0,1                                   #  X1=-NR
054120,000493: 27,3607           00043                           STORE    TFFX                                  #  X
054121,000494: 27,3610           41234                           RTB      DMP                                   
054122,000495: 27,3611           57734                                    T(X)                                  #   POLY
054123,000496:                                                                                                  #  ZSQ FROM PDL+2  E: (-26)  M: (-24)
054124,000497: 27,3612           44302                           SR2      BDSU                                  #  2 ZSQ T(X)  E: (-29)  M: (-27)
054125,000498: 27,3613           00023                                    RTERM                                 #  RTERM  E: (-29)  M: (-27)
054126,000499: 27,3614           41215                           DAD      DMP                                   
054127,000500: 27,3615           00015                                    RMAG1                                 #  E: (-29)  M: (-27)
054128,000501:                                                                                                  #  Z FROM PDL+0  E: (-13)  M: (-12)
054129,000502: 27,3616           51042                           SR3      BPL                                   #  TFF SQRT(MU)   E: (-45)  M: (-42)
054130,000503: 27,3617           57640                                    ENDTFF                                #  (NO PUSH UP)
054131,000504: 27,3620           75206                           PUSH     SIGN                                  #  TFF SQRT(MU)  TO PDL+0
054132,000505: 27,3621           00017                                    TFFQ1                                 #  Q1 FOR GONEPAST TEST
054133,000506: 27,3622           71244                           BPL      DLOAD                                 #  GONE PAST ?
054134,000507: 27,3623           57644                                    NEGTFF                                #  YES. TFF < 0 .
054135,000508: 27,3624           00027                                    TFF1/ALF                              #  1/ALFA  E: (-22-2NA)  M: (-20-2NA)
054136,000509: 27,3625           51076                           DCOMP    BPL                                   #  ALFA > 0 ?
054137,000510: 27,3626           57644                                    NEGTFF                                #  NO. TFF IS NEGATIVE.
054138,000511: 
054139,000512:                                                                                                  #                                          CORRECT FOR ORBITAL PERIOD.
054140,000513: 
054141,000514: 27,3627           77676                           DCOMP                                          #  YES. CORRECT FOR ORB PERIOD.
054142,000515: 27,3630           56205                           DMP      DDV                                   
054143,000516: 27,3631           17754                                    PI/16                                 #  2 PI (-5)
054144,000517: 27,3632           00031                                    TFFRTALF                              #  SQRT(ALFA)  E: (10+NA)  M: (9+NA)
054145,000518: 27,3633           53657                           SL*      SL*                                   
054146,000519: 27,3634           57602                                    0          -4,2                       #  X2=-NA
054147,000520: 27,3635           57602                                    0          -4,2                       
054148,000521: 27,3636           43257                           SL*      DAD                                   
054149,000522: 27,3637           57576                                    0,2                                   
054150,000523:                                                                                                  #  TFF SQRT(MU) FROM PDL+0  E:(-45) M:(-42)
054151,000524: 27,3640           40005        ENDTFF             DMP      BOV                                   #  TFF SQRT(MU) IN MPAC     E:(-45) M:(-42)
054152,000525: 27,3641           00037                                    TFF/RTMU                              #  E: (17)  M: (14)
054153,000526: 27,3642           57650                                    MAXTFF                                #  SET POSMAX IF OVFL.
054154,000527: 
054155,000528: 27,3643           77616        DUMPTFF2           RVQ                                            #  RETURN  TFF   (-28) CS IN MPAC.
054156,000529: 

Page 1269

054158,000531: 27,3644           77745        NEGTFF             DLOAD                                          
054159,000532:                                                                                                  #  TFF SQRT(MU)  FROM PDL+0, NEGATIVE.
054160,000533: 27,3645           77650                           GOTO                                           
054161,000534: 27,3646           57640                                    ENDTFF                                
054162,000535: 
054163,000536: 27,3647           77745        MAXTFF1            DLOAD                                          #  RESET PDL
054164,000537: 27,3650           43545        MAXTFF             DLOAD    RVQ                                   
054165,000538: 27,3651           17770                                    NEARONE                               
054166,000539: 
054167,000540:                                                                                                  #  TIME OF FLIGHT ELLIPSE WHEN DEL (ECCENTRIC ANOM) GEQ 90 AND LEQ -90.
054168,000541: 
054169,000542:                                                                                                  #  NUM FROM TFFX.  E: (-16) OR (-29)
054170,000543:                                                                                                  #                  M: (-15) OR (-27)
054171,000544: 27,3652           77712        TFFELL             SL2                                            #  NUM  E:(-14) OR (-27)  M:(-13) OR (-25)
054172,000545: 27,3653           41465                           BDDV     PUSH                                  #  TEMP SAVE D/N IN PDL+0
054173,000546:                                                                                                  #  DEN FROM PDL+0 E:(-3)/( 16) M:(-3)/(-15)
054174,000547:                                                                                                  #  N/D TO PDL+0  E: (11)  M: (10)
054175,000548: 27,3654           45345        TFFEL1             DLOAD    DSU                                   #  (ENTER WITH D/N=0 IN PDL+0)
054176,000549: 27,3655           00045                                    TFFTEM                                #  Q2  E: (-16)  M: (-15)
054177,000550: 27,3656           00017                                    TFFQ1                                 #  Q1  E: (-16)  M: (-15)
054178,000551: 27,3657           14013                           STODL    TFFDELQ                               #  Q2-Q1  E: (-16)  M: (-15)
054179,000552:                                                                                                  #  D/N FROM PDL+0
054180,000553: 27,3660           77626                           STADR                                          
054181,000554: 27,3661           77732                           STORE    TFFTEM                                #  D/N  E: (11)  M: (10)
054182,000555: 27,3662           53605                           DMP      SL*                                   
054183,000556: 27,3663           00027                                    TFF1/ALF                              #  1/ALFA E: (-22-2NA)  M: (-20-2NA)
054184,000557: 27,3664           57576                                    0,2                                   #  1/ALFA Z  E: (-11-NA)  M: (-10-NA)
054185,000558: 27,3665           41206                           PUSH     DMP                                   #  TO PDL+0
054186,000559: 27,3666           00045                                    TFFTEM                                #  1/Z  E: (11)  M: (10)
054187,000560: 27,3667           41057                           SL*      BOVB                                  
054188,000561: 27,3670           57576                                    0,2                                   #  X2= -NA
054189,000562: 27,3671           21713                                    SIGNMPAC                              #  IN CASE X= 1.0, CONTINUE
054190,000563: 27,3672           00043                           STORE    TFFX                                  #  X=1/ALFA ZSQ
054191,000564: 27,3673           41234                           RTB      DMP                                   
054192,000565: 27,3674           57734                                    T(X)                                  #  POLY
054193,000566: 27,3675           00043                                    TFFX                                  
054194,000567: 27,3676           45242                           SR3      DSU                                   
054195,000568: 27,3677           17762                                    DP2(-3)                               
054196,000569: 27,3700           41405                           DMP      PUSH                                  #  2(X T(X)-1) /Z ALFA  E: (-15-NA)
054197,000570:                                                                                                  #                       M: (-14-NA)
054198,000571:                                                                                                  #  1/ALFA Z FROM PDL+0  E: (-11-NA)
054199,000572:                                                                                                  #                       M: (-10-NA)
054200,000573: 27,3701           41345                           DLOAD    DMP                                   #  GET SIGN FOR SDELF
054201,000574: 27,3702           00045                                    TFFTEM                                #  1/Z  E: (11)  M: (10)
054202,000575: 27,3703           00015                                    RMAG1                                 #  E: (-29)  M: (-27)
054203,000576: 27,3704           43312                           SL2      DAD                                   
054204,000577: 27,3705           00017                                    TFFQ1                                 #  Q1  E: (-16)  M: (-15)
054205,000578: 27,3706           14045                           STODL    TFFTEM                                #  (Q1+R 1/Z)  =SGN OF SDELF E:(-16) M:(-15
054206,000579: 27,3707           00035                                    TFFNP                                 #  LC P E: (-38+2NR) M: (-36+2NR)
054207,000580: 27,3710           53605                           DMP      SL*                                   #  CALC FOR ARG FOR TFF/TRIG.

Page 1270

054209,000582: 27,3711           00027                                    TFF1/ALF                              #  1/ALFA   E:(-22-2NA)  M:(-20-2NA)
054210,000583: 27,3712           57575                                    1,2                                   #  X2=-NA
054211,000584: 27,3713           53765                           SIGN     SL*                                   
054212,000585: 27,3714           00045                                    TFFTEM                                #  AFFIX SIGN FOR SDELF
054213,000586: 27,3715           57576                                    0,2                                   
054214,000587: 27,3716           14045                           STODL    TFFTEM                                #  P/ALFA  E:(-59+2NR)  M:(-55+2NR)
054215,000588:                                                                                                  #  (ARG FOR USE IN TFF/TRIG)
054216,000589: 27,3717           00027                                    TFF1/ALF                              #  1/ALFA E:(-22-2NA)  M:(-20-2NA)
054217,000590: 27,3720           41366                           SQRT     DMP                                   
054218,000591: 27,3721           17754                                    PI/16                                 #  PI (-4)
054219,000592: 27,3722           77615                           DAD                                            
054220,000593:                                                                                                  #  2(XT(X)-1)/Z ALFA FROM PDL E:(-15-NA)
054221,000594:                                                                                                  #                             M:(-14-NA)
054222,000595: 27,3723           45257                           SL*      DSU                                   
054223,000596: 27,3724           57577                                    0          -1,2                       
054224,000597: 27,3725           00013                                    TFFDELQ                               #  Q2-Q1  E: (-16)  M: (-15)
054225,000598: 27,3726           53605                           DMP      SL*                                   
054226,000599: 27,3727           00027                                    TFF1/ALF                              #  1/ALFA  E:(-22-2NA)  M:(-20-2NA)
054227,000600: 27,3730           57601                                    0          -3,2                       
054228,000601: 27,3731           52057                           SL*      GOTO                                  
054229,000602: 27,3732           57602                                    0          -4,2                       
054230,000603: 27,3733           57640                                    ENDTFF                                #  TFF SQRT(MU) IN MPAC E:(-45) M:(-42)
054231,000604: 

Page 1271

054233,000606:                                                                                                  #  PROGRAM NAME:      T(X)                                                 DATE:    01.17.67
054234,000607:                                                                                                  #  MOD NO:  0                                                              LOG SECTION:    TIME OF FREE FALL
054235,000608:                                                                                                  #  MOD BY:  RR BAIRNSFATHER
054236,000609:                                                                                                  #  FUNCTIONAL DESCRIPTION:      THE POLYNOMIAL T(X) IS USED BY TIME OF FLIGHT SUBROUTINES  CALCTFF AND
054237,000610:                                                                                                  #           CALCTPER TO APPROXIMATE THE SERIES
054238,000611:                                                                                                  #                             2     3
054239,000612:                                                                                                  #                  1/3 -X/5 +X /7 -X /9 ...
054240,000613: 
054241,000614:                                                                                                  #           WHERE  X = ALFA Z Z       IF ALFA Z Z  LEQ 1
054242,000615:                                                                                                  #                  X = 1/(ALFA Z Z )  IF ALFA Z Z   G  1
054243,000616: 
054244,000617:                                                                                                  #           ALSO   X IS NEG FOR HYPERBOLIC ORBITS
054245,000618:                                                                                                  #                  X = 0 FOR PARABOLIC ORBITS
054246,000619:                                                                                                  #                  X IS POSITIVE FOR ELLIPTIC ORBITS
054247,000620:                                                                                                  #           FOR FLIGHT 278, THE POLYNOMIAL  T(X) IS FITTED OVER THE RANGE  (0,+1)  AND HAS A MAXIMUM
054248,000621:                                                                                                  #           DEVIATION FROM THE SERIES OF  2 E-5       (T(X) IS A CHEBYCHEV  TYPE FIT AND WAS OBTAINED USING
054249,000622:                                                                                                  #           MAC PROGRAM AUTCURFIT294RRB  AND IS VALID TO THE SAME TOLERANCE OVER THE RANGE  (-.08,+1). )
054250,000623:                                                                                                  #  CALLING SEQUENCE:  RTB
054251,000624:                                                                                                  #                            T(X)
054252,000625:                                                                                                  #           C(MPAC) = X
054253,000626: 
054254,000627:                                                                                                  #  SUBROUTINES CALLED:  NONE
054255,000628:                                                                                                  #  NORMAL EXIT MODE:    TC   DANZIG
054256,000629:                                                                                                  #  ALARMS:  NONE
054257,000630:                                                                                                  #  OUTPUT:  C(MPAC) = T(X)
054258,000631:                                                                                                  #  ERASABLE INITIALIZATION REQUIRED:
054259,000632:                                                                                                  #           C(MPAC)  =  X
054260,000633:                                                                                                  #  DEBRIS:  NONE
054261,000634: 
054262,000635: 27,3734           07225        T(X)               TC       POLY                                  
054263,000636: 27,3735           00004                           DEC      4          B-14                       #  N-1
054264,000637: 27,3736           12525 12525                     2DEC     3.333333333 E-1                        
054265,000638: 
054266,000639: 27,3740           71463 57703                     2DEC*    -1.999819135 E-1*                       
054267,000640: 
054268,000641: 27,3742           04423 17645                     2DEC*    1.418148467 E-1*                       
054269,000642: 
054270,000643: 27,3744           74604 43667                     2DEC*    -1.01310997 E-1*                       
054271,000644: 
054272,000645: 27,3746           01626 37256                     2DEC*    5.609004986 E-2*                       
054273,000646: 
054274,000647: 27,3750           77404 52071                     2DEC*    -1.536156925 E-2*                       
054275,000648: 
054276,000649: 27,3752           06064        ENDT(X)            TC       DANZIG                                
054277,000650: 
054278,000651: 27,3753  27,3752               TCDANZIG           =        ENDT(X)                               
054279,000652: 

Page 1272

054281,000654:                                                                                                  #  TFF CONSTANTS
054282,000655: 
054283,000656: 32,3652                                           BANK     32                                    
054284,000657: 
054285,000658: 27,2000                                           SETLOC   TOF-FF1                               
054286,000659: 27,2000                                           BANK                                           
054287,000660: 
054288,000661:                                                                                                  #                             NOTE _  NOTE _ ADJUSTED MUE FOR NEAR EARTH TRAJ.
054289,000662: 
054290,000663:                                                                                                  # MUE            =       3.990 815 471 E10  M CUBE/CS SQ
054291,000664:                                                                                                  # RTMUE          =       1.997702549 E5 B-18*     MODIFIED EARTH MU
054292,000665: 
054293,000666:                                                                                                  #                             NOTE _  NOTE _ ADJUSTED MUE FOR NEAR EARTH TRAJ.
054294,000667: 
054295,000668:                                                                                                  # MUM            =       4.902 778  E8     M CUBE /CS SQ
054296,000669: 
054297,000670:                                                                                                  # RTMUM          2DEC*   2.21422176 E4 B-18*
054298,000671: 27,3753           06220 37553  PI/16              2DEC     3.141592653 B-4                        
054299,000672: 
054300,000673: 27,3755           37777 37700  LIM(-22)           2OCT     3777737700                            #  1.0 -B(-22)
054301,000674: 
054302,000675: 27,3757           00000 00100  DP(-22)            2OCT     0000000100                            #  B(-22)
054303,000676: 
054304,000677: 27,3761           04000 00000  DP2(-3)            2DEC     1          B-3                        
054305,000678: 
054306,000679: 27,3763           02000 00000  DP2(-4)            2DEC     1          B-4                        #  1/16
054307,000680: 
054308,000681:                                                                                                  # RPAD1          2DEC    6373338 B-29      M  (-29)   =20 909 901.57 FT
054309,000682: 
054310,000683: 27,3765  23,2333               RPAD1              =        RPAD                                  
054311,000684: 
054312,000685: 27,3765           00305 11205  R300K              2DEC     6464778    B-29                       #  (-29) M
054313,000686: 
054314,000687: 27,3767           37777 37777  NEARONE            2DEC     .999999999                            
054315,000688: 
054316,000689: 27,3771  23,2517               TFFZEROS           EQUALS   HI6ZEROS                              
054317,000690: 27,3771  23,2507               TFF1/4             EQUALS   HIDP1/4                               
054318,000691: 

End of include-file TIME_OF_FREE_FALL.agc.  Parent file is MAIN.agc