Source Code
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These source-code files derive from a printout of Luminary 210 (Apollo 15-17
Lunar Module guidance computer program), from the personal library of
original AGC developer Don Eyles, digitally photographed at archive.org,
financially sponsored by Jim Lawton, and transcribed to source code by a
team of volunteers. This colorized, syntax-highlighted form was created
by assembling that transcribed source code. Note that the full page images
are available on the
Virtual AGC project page at archive.org, while reduced-size images
are presented at the VirtualAGC project website. Report or fix any
transcription errors at
the Virtual AGC project code repository. Notations on the program listing read, in part: GAP: ASSEMBLE REVISION 210 OF AGC PROGRAM LUMINARY BY NASA 2021112-161 17:11 MAR. 19,1971Note that the date is the date of the printout, not the date of the program revision. |
054564,000002: ## Copyright: Public domain.
054565,000003: ## Filename: TIME_OF_FREE_FALL.agc
054566,000004: ## Purpose: A section of Luminary revision 210.
054567,000005: ## It is part of the source code for the Lunar Module's (LM)
054568,000006: ## Apollo Guidance Computer (AGC) for Apollo 15-17.
054569,000007: ## This file is intended to be a faithful transcription, except
054570,000008: ## that the code format has been changed to conform to the
054571,000009: ## requirements of the yaYUL assembler rather than the
054572,000010: ## original YUL assembler.
054573,000011: ## Reference: pp. 1265-1280
054574,000012: ## Assembler: yaYUL
054575,000013: ## Contact: Ron Burkey <info@sandroid.org>.
054576,000014: ## Website: www.ibiblio.org/apollo/index.html
054577,000015: ## Mod history: 2016-11-17 JL Created from Luminary131 version.
054578,000016: ## 2016-12-10 MAS Began transcription.
054579,000017: ## 2016-12-10 MAS Completed transcription.
054580,000018: ## 2016-12-26 RSB Comment-text proofed using ProoferComments
054581,000019: ## and corrected errors found.
054582,000020:
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Page 1265 |
054584,000022: # THE TFF SUBROUTINES MAY BE USED IN EITHER EARTH OR MOON CENTERED COORDINATES. THE TFF ROUTINES NEVER
054585,000023: # KNOW WHICH ORIGIN APPLIES. IT IS THE USER WHO KNOWS, AND WHO SUPPLIES RONE, VONE AND 1/SQRT(MU) AT THE
054586,000024: # APPROPRIATE SCALE LEVEL FOR THE PROPER PRIMARY BODY.
054587,000025:
054588,000026: # EARTH ORIGIN POSITION -29 METERS
054589,000027: # VELOCITY -7 METERS/CENTISECOND
054590,000028: # 1/SQRT(MU) +17 SQRT(CS SQ/METERS CUBED)
054591,000029:
054592,000030: # MOON ORIGIN POSITION -27 METERS
054593,000031: # VELOCITY -5 METERS/CENTISECONDS
054594,000032: # 1/SQRT(MU) +14 SQRT(CS SQ/METERS CUBED)
054595,000033:
054596,000034: # ALL DATA PROVIDED TO AND RECEIVED FROM ANY TFF SUBROUTINE WILL BE AT ONE OF THE LEVELS ABOVE. IN ALL CASES,
054597,000035: # THE FREE FALL TIME IS RETURNED IN CENTISECONDS AT (-28). PROGRAM TFF/CONIC WILL GENERATE VONE/RTMU AND
054598,000036: # LEAVE IT IN VONE' AT (+10) IF EARTH ORIGIN AND (+9) IF MOON ORIGIN.
054599,000037: # THE USER MUST STORE THE STATE VECTOR IN RONE, VONE AND MU IN THE FORM 1/SQRT(MU) IN TFF/RTMU
054600,000038: # AT THE PROPER SCALE BEFORE CALLING TFF/CONIC. SINCE RONE, VONE ARE IN THE EXTENDED VERB STORAGE AREA,
054601,000039: # THE USER MUST ALSO LOCK OUT THE EXTENDED VERBS, AND RELEASE THEM WHEN FINISHED.
054602,000040: # PROGRAMS CALC/TFF AND CALC/TPER ASSUME THAT THE TERMINAL RADIUS IS LESS THAN THE PRESENT
054603,000041: # RADIUS. THIS RESTRICTION CAN BE REMOVED BY A 15 W CODING CHANGE, BUT AT PRESENT IT IS NOT DEEMED NECESSARY.
054604,000042:
054605,000043: # THE FOLLOWING ERASABLE QUANTITIES ARE USED BY THE TFF ROUTINES, AND ARE LOCATED IN THE PUSH LIST.
054606,000044:
054607,000045: # BELOW E: IS USED FOR EARTH ORIGIN SCALE
054608,000046: # M: IS USED FOR MOON ORIGIN SCALE
054609,000047:
054610,000048: # TFFSW = 119D BIT1 0 = CALCTFF 1 = CALCTPER
054611,000049: 10,2213 TFFDELQ = 10D # Q2-Q1 E: (-16) M: (-15)
054612,000050: 10,2213 RMAG1 = 12D # ABVAL(RN) M E: (-29) M: (-27)
054613,000051: # RPER = 14D PERIGEE RADIUS M E: (-29) M: (-27)
054614,000052: 10,2213 TFFQ1 = 14D # R.V / SQRT(MUE) E: (-16) M: (-15)
054615,000053: # SDELF/2 SIN(THETA) /2
054616,000054: 10,2213 CDELF/2 = 14D # COS(THETA) /2
054617,000055: # RAPO = 16D APOGEE RADIUS M E: (-29) M: (-27)
054618,000056: 10,2213 NRTERM = 16D # TERMINAL RADIUS M E: (-29+NR)
054619,000057: # M: (-27+NR)
054620,000058: 10,2213 RTERM = 18D # TERMINAL RADIUS M E: (-29) M: (-27)
054621,000059: 10,2213 TFFVSQ = 20D # -(V SQUARED/MU) 1/M E: (20) M: (18)
054622,000060: 10,2213 TFF1/ALF = 22D # SEMI MAJ AXIS M E: (-22-2 NA)
054623,000061: # M: (-20-2 NA)
054624,000062: 10,2213 TFFRTALF = 24D # SQRT(ALFA) E: (10+NA) M: (9+NA)
054625,000063: 10,2213 TFFALFA = 26D # ALFA 1/M E: (26-NR) M: (24-NR)
054626,000064: 10,2213 TFFNP = 28D # SEMI LATUS RECTUM M E: (-38+2 NR)
054627,000065: # M: (-36+2 NR)
054628,000066: 10,2213 TFF/RTMU = 30D # 1/SQRT(MU) E: (17) M: (14)
054629,000067: 10,2213 NRMAG = 32D # PRESENT RADIUS M E: (-29+NR)
054630,000068: # M: (-27+NR)
054631,000069: 10,2213 TFFX = 34D
054632,000070: 10,2213 TFFTEM = 36D # TEMPORARY
054633,000071:
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Page 1266 |
054635,000073: # REGISTERS S1, S2 ARE UNTOUCHED BY ANY TFF SUBROUTINE
054636,000074: # INDEX REGISTERS X1, X2 ARE USED BY ALL TFF SUBROUTINES. THEY ARE ESTAB-
054637,000075: # LISHED IN TFF/CONIC AND MUST BE PRESERVED BETWEEN CALLS TO SUBSEQUENT
054638,000076: # SUBROUTINES.
054639,000077: # -NR C(X1) = NORM COUNT OF RMAG
054640,000078: # -NA C(X2)= NORM COUNT OF SQRT(ABS(ALFA))
054641,000079:
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Page 1267 |
054643,000081:
054644,000082:
054645,000083: # SUBROUTINE NAME: TFFCONIC DATE: 01.29.67
054646,000084: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
054647,000085: # MOD BY: RR BAIRNSFATHER
054648,000086: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 11 APR 67
054649,000087: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 21 NOV 67 ADD MOON MU.
054650,000088: # MOD NO: 3 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
054651,000089: # FUNCTIONAL DESCRIPTION: THIS SUBROUTINE IS CALLED TO COMPUTE THOSE CONIC PARAMETERS REQUIRED BY THE TFF
054652,000090: # SUBROUTINES AND TO ESTABLISH THEM IN THE PUSH LIST AREA. THE PARAMETERS ARE LISTED UNDER OUTPUT.
054653,000091: # THE EQUATIONS ARE
054654,000092: # - - -
054655,000093: # H = RN*VN ANGULAR MOMENTUM
054656,000094: # - -
054657,000095: # LCP = H.H / MU SEMI LATUS RECTUM
054658,000096: # - -
054659,000097: # ALFA = 2/RN - VN.VN / MU RECIPROCAL SEMI MAJ AXIS, SIGNED
054660,000098:
054661,000099: # AND ALFA IS POS FOR ELLIPTIC ORBITS
054662,000100: # 0 FOR PARABOLIC ORBITS
054663,000101: # NEG FOR HYPERBOLIC ORBITS.
054664,000102: # SUBROUTINE ALSO COMPUTES AND SAVES RMAG.
054665,000103: # CALLING SEQUENCE:
054666,000104: # TFFCONIC EXPECTS CALLER TO ENTER WITH CORRECT GRAVITATIONAL CONSTANT IN MPAC, IN THE FORM
054667,000105: # 1/SQRT(MU). PROGRAM WILL SAVE IN TFF/RTMU . THE SCALE IS DETERMINED BY WHETHER EARTH OR MOON
054668,000106: # ORIGIN IS USED. THE CALLER MUST LOCK OUT THE EXTENDED VERBS BEFORE PROVIDING STATE VECTOR IN RONE,
054669,000107: # VONE AT PROPER SCALE. THE EXTENDED VERBS MUST BE RESTORED WHEN THE CALLER IS FINISHED USING THE
054670,000108: # TFF ROUTINES.
054671,000109: # ENTRY POINT TFFCONMU EXPECTS THAT TFF/RTMU IS ALREADY LOADED.
054672,000110: # TO SPECIFY MU: DLOAD CALL IF MU ALREADY STORED: CALL
054673,000111: # YOURMU 1/RTMU E: (17) M: (14) TFFCONMU
054674,000112: # TFFCONIC
054675,000113: # PUSHLOC = PDL+0, ARBITRARY IF LEQ 18D
054676,000114:
054677,000115: # SUBROUTINES CALLED: NONE
054678,000116: # NORMAL EXIT MODES: RVQ
054679,000117: # ALARMS: NONE
054680,000118: # OUTPUT: THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
054681,000119: # RMAG1 E:(-29) M:(-27) M RN, PRESENT RADIUS LENGTH.
054682,000120: # NRMAG E: (-29+NR) M RMAG, NORMALIZED
054683,000121: # M: (-27+NR)
054684,000122: # X1 -NR, NORM COUNT
054685,000123: # TFFNP E: (-38+2NR) M LCP, SEMI LATUS RECTUM, WEIGHTED BY NR. FOR VGAMCALC
054686,000124: # M: (-36+2NR)
054687,000125: # TFF/RTMU E:(17) M:(14) 1/SQRT(MU)
054688,000126: # TFFVSQ E:(20) M:(18) 1/M -(V SQ/MU): PRESENT VELOCITY,NORMLIZED. FOR VGAMCALC
054689,000127: # TFFALFA E: (26-NR) 1/M ALFA, WEIGHTED BY NR
054690,000128: # M: (24-NR)
054691,000129: # TFFRTALF E: (10+NA) SQRT(ALFA), NORMALIZED
054692,000130: # M: (9+NA)
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Page 1268 |
054694,000132: # X2 -NA, NORM COUNT
054695,000133: # TFF1/ALF E: (-22-2NA) SIGNED SEMI MAJ AXIS, WEIGHTED BY NA
054696,000134: # M: (-20-2NA)
054697,000135: # PUSHLOC AT PDL+0
054698,000136: # THE FOLLOWING IS STORED IN GENERAL ERASABLE
054699,000137: # VONE' E:(10) M:(9) V/RT(MU), NORMALIZED VELOCITY
054700,000138: # ERASABLE INITIALIZATION REQUIRED:
054701,000139: # RONE E:(-29) M:(-27) M STATE VECTOR LEFT BY CALLER
054702,000140: # VONE E:(-7) M:(-5) M/CS STATE VECTOR LEFT BY CALLER
054703,000141: # TFF/RTMU E:(17) M:(14) 1/RT(CS SQ/M CUBE) IF ENTER VIA TFFCONMU.
054704,000142: # DEBRIS: QPRET, PDL+0 ... PDL+3
054705,000143:
054706,000144:
054707,000145: 33,3575 BANK 33
054708,000146: 27,2000 SETLOC TOF-FF
054709,000147: 27,2000 BANK
054710,000148:
054711,000149: 27,3363 COUNT* $$/TFF
054712,000150:
054713,000151: 27,3363 00037 TFFCONIC STORE TFF/RTMU # 1/SQRT(MU) E: (17) M: (14)
054714,000152:
054715,000153: 27,3364 53575 TFFCONMU VLOAD UNIT # COME HERE WITH TFFRTMU LOADED.
054716,000154: 27,3365 02200 RONE # SAVED RN. M E: (-29) M: (-27)
054717,000155: 27,3366 77725 PDDL # UR/2 TO PDL+0, +5
054718,000156: 27,3367 00045 36D # MAGNITUDE
054719,000157: 27,3370 00015 STORE RMAG1 # M E: (-29) M: (-27)
054720,000158:
054721,000159: 27,3371 77701 NORM
054722,000160: 27,3372 00047 X1 # -NR
054723,000161: 27,3373 24041 STOVL NRMAG # RMAG M E: (-29+NR) M: (-27+NR)
054724,000162: 27,3374 02206 VONE # SAVED VN. M/CS E: (-7) M: (-5)
054725,000163: 27,3375 77761 VXSC
054726,000164: 27,3376 00037 TFF/RTMU # E: (17) M: (14)
054727,000165: 27,3377 02161 STORE VONE' # VN/SQRT(MU) E: (10) M: (9)
054728,000166:
054729,000167: 27,3400 47361 VXSC VXV
054730,000168: 27,3401 00041 NRMAG # E: (-29+NR) M: (-27+NR)
054731,000169: # UR/2 FROM PDL
054732,000170: 27,3402 47572 VSL1 VSQ # BEFORE: E:(-19+NR) M:(-18+NR)
054733,000171: 27,3403 14035 STODL TFFNP # LC P M E:(-38+2NR) M:(-36+2NR)
054734,000172: # SAVE ALSO FOR VGAMCALC
054735,000173: 27,3404 06475 TFF1/4
054736,000174: 27,3405 63271 DDV PDVL # (2/RMAG) 1/M E:(26-NR) M:(24-NR)
054737,000175: 27,3406 00041 NRMAG # RMAG M E:(-29+NR) M:(-27+NR)
054738,000176: 27,3407 02161 VONE' # SAVED VN. E: (10) M: (9)
054739,000177: 27,3410 57436 VSQ DCOMP # KEEP MPAC+2 HONEST FOR SQRT.
054740,000178: 27,3411 00025 STORE TFFVSQ # -(V SQ/MU) E:(20) M:(18)
054741,000179: # SAVE FOR VGAMCALC
054742,000180: 27,3412 43257 SR* DAD
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Page 1269 |
054744,000182: 27,3413 20573 0 -6,1 # GET -VSQ/MU E:(26-NR) M:(24-NR)
054745,000183: 27,3414 77626 STADR
054746,000184: # 2/RMAG FROM PDL+2
054747,000185: 27,3415 77744 STORE TFFALFA # ALFA 1/M E:(26-NR) M:(24-NR)
054748,000186: 27,3416 41457 SL* PUSH # TEMP SAVE ALFA E:(20) M:(18)
054749,000187: 27,3417 20173 0 -6,1
054750,000188: 27,3420 75446 ABS SQRT # E:(10) M:(9)
054751,000189: 27,3421 77701 NORM
054752,000190: 27,3422 00050 X2 # X2 = -NA
054753,000191: 27,3423 00031 STORE TFFRTALF # SQRT( ABS(ALFA) ) E:(10+NA) M:(9+NA)
054754,000192: 27,3424 75316 DSQ SIGN # NOT SO ACCURATE, BUT OK
054755,000193: # ALFA FROM PDL+2 E:(20) M:(18)
054756,000194: 27,3425 55254 BZE BDDV # SET 1/ALFA =0, TO SHOW SMALL ALFA
054757,000195: 27,3426 57430 +2
054758,000196: 27,3427 06475 TFF1/4
054759,000197: 27,3430 00027 +2 STORE TFF1/ALF # 1/ALFA E:(-22-2 NA) M:(-20-2 NA)
054760,000198: 27,3431 77616 DUMPCNIC RVQ
054761,000199:
054762,000200: # 39 W
054763,000201:
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Page 1270 |
054765,000203: # SUBROUTINE NAME: TFFRP/RA DATE: 01.17.67
054766,000204: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
054767,000205: # MOD BY: RR BAIRNSFATHER
054768,000206: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 11 APR 67
054769,000207: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
054770,000208: # ALSO IMPROVE ACCURACY OF RAPO.
054771,000209: # FUNCTIONAL DESCRIPTION: USED BY CALCTPER AND TFF DISPLAYS TO CALCULATE PERIGEE RADIUS AND ALSO
054772,000210: # APOGEE RADIUS FOR A GENERAL CONIC.
054773,000211: # PROGRAM GIVES PERIGEE RADIUS AS APOGEE RADIUS IS GIVEN BY
054774,000212: # RP = P /(1+E) RA = (1+E) / ALFA
054775,000213: # WHERE 2
054776,000214: # E = 1 - P ALFA
054777,000215: # IF RA IS NEGATIVE OR SHOWS DIVIDE OVERFLOW, THEN RA = POSMAX BECAUSE
054778,000216: # 1. APOGEE RADIUS IS NOT MEANINGFUL FOR HYPERBOLA
054779,000217: # 2. APOGEE RADIUS IS NOT DEFINED FOR PARABOLA
054780,000218: # 3. APOGEE RADIUS EXCEEDS THE SCALING FOR ELLIPSE.
054781,000219: # THIS SUBROUTINE REQUIRES THE SIGNED RECIPROCAL SEMI MAJ AXIS, ALFA, AND SEMI LATUS RECTUM AS DATA.
054782,000220: # CALLING SEQUENCE: CALL
054783,000221: # TFFRP/RA
054784,000222: # PUSHLOC = PDL+0, ARBITRARY IF LEQ 10D
054785,000223: # C(MPAC) UNSPECIFIED
054786,000224:
054787,000225: # SUBROUTINES CALLED: NONE
054788,000226: # NORMAL EXIT MODE: RVQ
054789,000227: # IF ELLIPSE, WITHIN NORMAL SCALING, RAPO IS CORRECT.
054790,000228: # OTHERWISE, RAPO = POSMAX.
054791,000229: # ALARMS: NONE
054792,000230: # OUTPUT: STORED IN PUSH LIST AREA. SCALE OF OUTPUT AGREES WITH DATA SUPPLIED TO TFF/CONIC.
054793,000231: # RPER E:(-29) M:(-27) M PERIGEE RADIUS DESTROYED BY CALCTFF/CALCTPER, TFFTRIG.
054794,000232: # RAPO E:(-29) M:(-27) M APOGEE RADIUS WILL BE DESTROYED BY CALCTFF/CALCTPER
054795,000233: # PUSHLOC AT PDL+0
054796,000234: # ERASABLE INITIALIZATION REQUIRED:
054797,000235: # TFFALFA E:(26-NR) M 1/SEMI MAJ AXIS LEFT BY TFFCONIC
054798,000236: # M:(24-NR)
054799,000237: # TFFNP E: (-38+2NR) M LC P, SEMI LATUS RECTUM LEFT BY TFFCONIC
054800,000238: # M: (-36+2NR)
054801,000239: # X1 -NR, NORM COUNT OF RMAG LEFT BY TFFCONIC
054802,000240: # X2 -NA, NORM COUNT OF ALFA LEFT BY TFFCONIC
054803,000241: # DEBRIS: QPRET, PDL+0 ... PDL+1
054804,000242:
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Page 1271 |
054806,000244: 27,3432 RAPO = 16D # APOGEE RADIUS M E:(-29) M:(-27)
054807,000245: 27,3432 RPER = 14D # PERIGEE RADIUS M E:(-29) M:(-27)
054808,000246:
054809,000247: 27,3432 41345 TFFRP/RA DLOAD DMP
054810,000248: 27,3433 00033 TFFALFA # ALFA 1/M E:(26-NR) M:(24-NR)
054811,000249: 27,3434 00035 TFFNP # LC P M E:(-38+2NR) M:(-36+2NR)
054812,000250: 27,3435 57457 SR* DCOMP # ALFA P (-12+NR)
054813,000251: 27,3436 20571 0 -8D,1 # ALFA P (-4)
054814,000252: 27,3437 51415 DAD ABS # (DCOMP GIVES VALID TP RESULT FOR SQRT)
054815,000253: # (ABS PROTECTS SQRT IF E IS VERY NEAR 0)
054816,000254: 27,3440 17770 DP2(-4)
054817,000255: 27,3441 43366 SQRT DAD # E SQ = (1- P ALFA) (-4)
054818,000256: 27,3442 06475 TFF1/4
054819,000257: 27,3443 55206 PUSH BDDV # (1+E) (-2) TO PDL+0
054820,000258: 27,3444 00035 TFFNP # LCP M E:(-38+2NR) M:(-36+2NR)
054821,000259: 27,3445 53657 SR* SR* # (DOES SR THEN SL TO AVOID OVFL)
054822,000260: 27,3446 20601 0,1 # X1=-NR
054823,000261: 27,3447 20572 0 -7,1 # (EFFECTIVE SL)
054824,000262: 27,3450 14017 STODL RPER # PERIGEE RADIUS M E:(-29) M:(-27)
054825,000263: # (1+E) (-2) FROM PDL+0
054826,000264: 27,3451 41005 DMP BOVB
054827,000265: 27,3452 00027 TFF1/ALF # E:(-22-2NA) M:(-20-2NA)
054828,000266: 27,3453 57756 TCDANZIG # CLEAR OVFIND, IF ON.
054829,000267: 27,3454 53654 BZE SL*
054830,000268: 27,3455 57464 MAXRA # SET POSMAX, IF ALFA=0
054831,000269: 27,3456 57603 0 -5,2 # -5+NA
054832,000270: 27,3457 40057 SL* BOV
054833,000271: 27,3460 57576 0,2
054834,000272: 27,3461 57464 MAXRA # SET POSMAX IF OVFL.
054835,000273: 27,3462 77644 BPL # CONTINUE WITH VALID RAPO.
054836,000274: 27,3463 57466 +3
054837,000275: 27,3464 77745 MAXRA DLOAD # RAPO CALC IS NOT VALID. SET RAPO =
054838,000276: 27,3465 17774 NEARONE # POSMAX AS A TAG.
054839,000277: 27,3466 00021 +3 STORE RAPO # APOGEE RADIUS M E:(-29) M:(-27)
054840,000278: 27,3467 77616 DUMPRPRA RVQ
054841,000279:
054842,000280: # 30 W
054843,000281:
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Page 1272 |
054845,000283: # SUBROUTINE NAME: CALCTPER / CALCTFF DATE: 01.29.67
054846,000284: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
054847,000285: # MOD BY: RR BAIRNSFATHER
054848,000286: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 67
054849,000287: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 14 APR 67
054850,000288: # MOD NO: 3 MOD BY: RR BAIRNSFATHER DATE: 8JUL 67 NEAR EARTH MUE AND NEG TFF (GONEPAST)
054851,000289: # MOD NO: 4 MOD BY: RR BAIRNSFATHER DATE: 21 NOV 67 ADD VARIABLE MU.
054852,000290: # MOD NO: 5 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
054853,000291: # FUNCTIONAL DESCRIPTION: PROGRAM CALCULATES THE FREE-FALL TIME OF FLIGHT FROM PRESENT POSITION RN AND
054854,000292: # VELOCITY VN TO A RADIUS LENGTH SPECIFIED BY RTERM , SUPPLIED BY THE USER. THE POSITION VECTOR
054855,000293: # RN MAY BE ON EITHER SIDE OF THE CONIC, BUT RTERM IS CONSIDERED ON THE INBOUND SIDE.
054856,000294: # THE EQUATIONS ARE
054857,000295:
054858,000296: # Q2 = -SQRT(RTERM (2-RTERM ALFA) - LCP) (INBOUND SIDE)) LEQ +- LCE/SQRT(ALFA)
054859,000297: # - -
054860,000298: # Q1 = RN.VN / SQRT(MU) LEQ +- LCE/SQRT(ALFA)
054861,000299:
054862,000300: # Z = NUM / DEN LEQ +- 1/SQRT(ALFA)
054863,000301:
054864,000302: # WHERE, IF INBOUND
054865,000303: # NUM = RTERM - RN LEQ +- 2 LCE/ALFA
054866,000304: # DEN = Q2+Q1 LEQ +- 2 LCE/SQRT(ALFA)
054867,000305:
054868,000306: # AND, IF OUTBOUND
054869,000307: # NUM = Q2-Q1 LEQ +- 2 LCE/SQRT(ALFA)
054870,000308: # DEN = 2 - ALFA (RTERM + RN) . LEQ +- 2 LCE
054871,000309:
054872,000310: # IF ALFA ZZ < 1.0 (FOR ALL CONICS EXCEPT ELLIPSES HAVING ABS(DEL ECC ANOM) G 90 DEG)
054873,000311:
054874,000312: # THEN X = ALFA Z Z
054875,000313: # AND TFF = (RTERM +RN -2 ZZ T(X) ) Z/SQRT(MU)
054876,000314:
054877,000315: # EXCEPT IF ALFA PNZ, AND IF TFF NEG,
054878,000316: # THEN TFF = 2 PI /(ALFA SQRT(ALFA)) + TFF
054879,000317:
054880,000318: # OR IF ALFA ZZ GEQ 1.0 (FOR ELLIPSES HAVING ABS(DEL ECC ANOM) GEQ 90 DEG)
054881,000319:
054882,000320: # THEN X = 1/ALFA Z Z
054883,000321: # AND TFF = (PI/SQRT(ALFA) -Q2 +Q1 +2(X T(X) -1) /ALFA Z) /ALFA SQRT(MU)
054884,000322:
054885,000323: # WHERE T(X) IS A POLYNOMIAL APPROXIMATION TO THE SERIES
054886,000324: # 2 3 2
054887,000325: # 1/3 -X/5 +X /7 -X /9 ... (X < 1.0)
054888,000326:
054889,000327: # CALLING SEQUENCE: TIME TO RTERM TIME TO PERIGEE
054890,000328: # CALL CALL
054891,000329: # CALCTFF CALCTPER
054892,000330: # C(MPAC) = TERMNL RAD M C(MPAC) = PERIGEE RAD M
054893,000331: # FOR EITHER, E: (-29) M: (-27)
054894,000332: # FOR EITHER, PUSHLOC = PDL+0, ARBITRARY IF LEQ 8D.
054895,000333:
![]() |
Page 1273 |
054897,000335: # SUBROUTINES CALLED: T(X), VIA RTB
054898,000336: # NORMAL EXIT MODE: RVQ
054899,000337: # HOWEVER, PROGRAM EXITS WITH ONE OF THE FOLLOWING VALUES FOR TFF (-28) CS IN MPAC. USER MUST STORE.
054900,000338: # A. TFF= FLIGHT TIME. NORMAL CASE FOR POSITIVE FLIGHT TIME LESS THAN ONE ORBITAL PERIOD.
054901,000339: # B. (THIS OPTION IS NO LONGER USED.)
054902,000340: # C. TFF = POSMAX. THIS INDICATES THAT THE CONIC FROM THE PRESENT POSITION WILL NOT RETURN TO
054903,000341: # THE SPECIFIED ALTITUDE. ALSO INDICATES OUTBOUND PARABOLA OR HYPERBOLA.
054904,000342: # OUTPUT: C(MPAC) (-28) CS TIME OF FLIGHT, OR TIME TO PERIGEE
054905,000343: # TFFX (0) X, LEFT FOR ENTRY DISPLAY TFF ROUTINES
054906,000344: # NRTERM E: (-29+NR) M RTERM, WEIGHTED BY NR LEFT FOR ENTRY DISPLAY TFF ROUTINES
054907,000345: # M: (-27+NR)
054908,000346: # TFFTEM E: (-59+2NR) LCP Z Z SGN(SDELF) LEFT FOR ENTRY DISPLAY TFF ROUTINES
054909,000347: # M: (-55+2NR) LCP /ALFA SGN(SDELF) LEFT FOR ENTRY DISPLAY TFF ROUTINES
054910,000348: # NOTE: TFFTEM = PDL 36D AND WILL BE DESTROYED BY .:UNIT:.
054911,000349: # RMAG1 E:(-29) M:(-27) PDL 12 NOT TOUCHED.
054912,000350: # TFFQ1 E:(-16) M:(-15) PDL 14D
054913,000351: # TFFDELQ E:(-16) M:(-15) PDL 10D
054914,000352: # PUSHLOC AT PDL+0
054915,000353: # ERASABLE INITIALIZATION REQUIRED:
054916,000354: # RONE E:(-29) M:(-27) M STATE VECTOR LEFT BY USER
054917,000355: # VONE' E:(+10) M:(+9) VN/SQRT(MU) LEFT BY TFF/CONIC
054918,000356: # RMAG1 E:(-29) M:(-27) PRESENT RADIUS, M LEFT BY TFFCONIC
054919,000357: # C(MPAC)E:(-29) M:(-27) RTERM, TERMINAL RADIUS LENGTH, M LEFT BY USER
054920,000358:
054921,000359: # THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
054922,000360: # TFF/RTMU E:(17) M:(14) 1/SQRT(MU) LEFT BY TFFCONIC.
054923,000361: # NRMAG E: (-29+NR) M RMAG, NORMALIZED LEFT BY TFFCONIC
054924,000362: # M: (-27+NR)
054925,000363: # X1 -NR, NORM COUNT LEFT BY TFFCONIC
054926,000364: # TFFNP E: (-38+2NR) M LCP, SEMI LATUS RECTUM, WEIGHT NR LEFT BY TFFCONIC
054927,000365: # M: (-36+2NR)
054928,000366: # TFFALFA E: (26-NR) 1/M ALFA, WEIGHT NR LEFT BY TFFCONIC
054929,000367: # M: (24-NR)
054930,000368: # TFFRTALF E:(10+NA) SQRT(ALFA), NORMALIZED LEFT BY TFFCONIC
054931,000369: # M:(9+NA)
054932,000370: # X2 -NA, NORM COUNT LEFT BY TFFCONIC
054933,000371: # TFF1/ALF E: (-22-2NA) SIGNED SEMIMAJ AXIS, WEIGHTED BY NA LEFT BY TFFCONIC
054934,000372: # M: (-20-2NA)
054935,000373: # DEBRIS: QPRET, PDL+0 ... PDL+3
054936,000374: # RTERM E:(-29) M:(-27) RTERM, TERMINAL RADIUS LENGTH
054937,000375: # RAPO E:(-29) M:(-27) PDL 16D (=NRTERM)
054938,000376: # RPER E:(-29) M:(-27) PDL 14D (=TFFQ1)
054939,000377:
![]() |
Page 1274 |
054941,000379: 27,3470 77614 CALCTPER SETGO # ENTER WITH RPER IN MPAC
054942,000380: 27,3471 03436 TFFSW
054943,000381: 27,3472 57475 +3
054944,000382: 27,3473 77614 CALCTFF CLEAR # ENTER WITH RTERM IN MPAC
054945,000383: 27,3474 03676 TFFSW
054946,000384: 27,3475 00023 +3 STORE RTERM # E: (-29) M: (-27)
054947,000385: 27,3476 77657 SL*
054948,000386: 27,3477 20201 0,1 # X1=-NR
054949,000387: 27,3500 00021 STORE NRTERM # RTERM E: (-29+NR) M: (-27+NR)
054950,000388: 27,3501 44205 DMP BDSU
054951,000389: 27,3502 00033 TFFALFA # ALFA E: (26-NR) M: (24-NR)
054952,000390: 27,3503 06475 TFF1/4
054953,000391: 27,3504 41206 PUSH DMP # (2-ALFA RTERM) (-3) TO PDL+0
054954,000392: 27,3505 00021 NRTERM # E: (-29+NR) M: (-27+NR)
054955,000393: 27,3506 53725 PDDL SR* # RTERM(2-ALFA RTERM) TO PDL+2
054956,000394: # E: (-32+NR) M: (-30+NR)
054957,000395: 27,3507 00035 TFFNP # LC P E:(-38+2NR) M:(-36+2NR)
054958,000396: 27,3510 20573 0 -6,1 # X1 = -NR
054959,000397: 27,3511 43276 DCOMP DAD # DUE TO SHIFTS, KEEP PRECISION FOR SQRT
054960,000398: # RTERM(2-ALFA RTERM) FROM PDL+2
054961,000399: # E: (-32+NR) M: (-30+NR)
054962,000400: 27,3512 77657 SR* # LEAVE E: (-32) M: (-30)
054963,000401: 27,3513 20601 0,1 # X1 = -NR
054964,000402: 27,3514 71214 BOFF DLOAD # CHECK TFF / TPER SWITCH
054965,000403: 27,3515 03756 TFFSW
054966,000404: 27,3516 57520 +2 # IF TFF, CONTINUE
054967,000405: 27,3517 06505 TFFZEROS # IF TPER, SET Q2 = 0
054968,000406: 27,3520 75440 +2 BMN SQRT # E: (-16) M: (-15)
054969,000407:
054970,000408: 27,3521 57653 MAXTFF1 # NO FREE FALL CONIC TO RTERM FROM HERE
054971,000409: # RESET PDL, SET TFF=POSMAX, AND EXIT.
054972,000410:
054973,000411: 27,3522 41076 DCOMP BOVB # RT IS ON INBOUND SIDE. ASSURE OVFIND=0
054974,000412: 27,3523 57756 TCDANZIG # ANY PORT IN A STORM.
054975,000413: 27,3524 24045 STOVL TFFTEM # Q2 E: (-16) M: (-15)
054976,000414: 27,3525 02161 VONE' # VN/SQRT(MU) E: (10) M: (9)
054977,000415: 27,3526 52441 DOT SL3
054978,000416: 27,3527 02200 RONE # SAVED RN. E: (-29) M: (-27)
054979,000417: 27,3530 00017 STORE TFFQ1 # Q1, SAVE FOR GONEPAST TEST.
054980,000418: # E: (-16) M: (-15)
054981,000419: 27,3531 44240 BMN BDSU
054982,000420: 27,3532 57553 INBOUND # USE ALTERNATE Z
054983,000421: 27,3533 00045 TFFTEM # Q2 E: (-16) M: (-15)
054984,000422:
054985,000423: # OUTBOUND Z CALC CONTINUES HERE
054986,000424:
054987,000425: 27,3534 14043 STODL TFFX # NUM=Q2-Q1 E: (-16) M: (-15)
054988,000426: 27,3535 00033 TFFALFA # ALFA E: (26-NR) M: (24-NR)
054989,000427: 27,3536 44205 DMP BDSU
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Page 1275 |
054991,000429: 27,3537 00041 NRMAG # RMAG E: (-29+NR) M: (-27+NR)
054992,000430: # (2-RTERM ALFA) (-3) FROM PDL+0
054993,000431: 27,3540 51406 SAVEDEN PUSH ABS # DEN TO PDL+0 E: (-3) OR (-16)
054994,000432: # M: (-3) OR (-15)
054995,000433: 27,3541 40015 DAD BOV # INDETERMINANCY TEST
054996,000434: 27,3542 17762 LIM(-22) # =1.0-B(-22)
054997,000435: 27,3543 57564 TFFXTEST # GO IF DEN >/= B(-22)
054998,000436: 27,3544 65345 DLOAD PDDL # SET DEN=0 OTHERWISE
054999,000437: 27,3545 06505 TFFZEROS
055000,000438: # XCH ZERO WITH PDL+0
055001,000439: 27,3546 57545 DLOAD DCOMP
055002,000440: 27,3547 00033 TFFALFA # ALFA E: (26-NR) M: (24-NR)
055003,000441: 27,3550 71240 BMN DLOAD # FOR TPER: Z INDET AT DELE/2=0 AND 90.
055004,000442: 27,3551 57660 TFFEL1 # ASSUME 90, AND LEAVE 0 IN PDL: 1/Z=D/N
055005,000443:
055006,000444: # Z INDET. AT PERIGEE FOR PARAB OR HYPERB.
055007,000445: 27,3552 77616 DUMPTFF1 RVQ # RETURN TFF =0
055008,000446:
055009,000447: # INBOUND Z CALC CONTINUES HERE
055010,000448: 27,3553 77745 INBOUND DLOAD # RESET PDL+0
055011,000449: 27,3554 45345 DLOAD DSU # ALTERNATE Z CALC
055012,000450: 27,3555 00023 RTERM # E: (-29) M: (-27)
055013,000451: 27,3556 00015 RMAG1 # E: (-29) M: (-27)
055014,000452: 27,3557 14043 STODL TFFX # NUM=RTERM-RN E: (-29) M: (-27)
055015,000453: 27,3560 00045 TFFTEM # Q2 E: (-16) M: (-15)
055016,000454: 27,3561 52015 DAD GOTO
055017,000455: 27,3562 00017 TFFQ1 # Q1 E: (-16) M: (-15)
055018,000456: 27,3563 57540 SAVEDEN # DEN = Q2+Q1 E: (-16) M: (-15)
055019,000457:
055020,000458: 27,3564 65215 TFFXTEST DAD PDDL # (ABS(DEN) TO PDL+2)) E: (-3) OR (-16)
055021,000459: # M: (-3) OR (-15)
055022,000460: 27,3565 17764 DP(-22) # RESTORE ABS(DEN) TO MPAC
055023,000461: 27,3566 00043 TFFX # NUM E:(-16) OR (-29) M:(-15) OR (-27)
055024,000462: 27,3567 53605 DMP SR*
055025,000463: 27,3570 00031 TFFRTALF # SQRT(ALFA) E: (10+NA) M: (9+NA)
055026,000464: 27,3571 57201 0 -3,2 # X2=-NA
055027,000465: 27,3572 77671 DDV # C(MPAC) =NUM SQRT(ALFA) E:(-3) OR (-16)
055028,000466: # M:(-3) OR (-15)
055029,000467: # ABS(DEN) FROM PDL+2 E:(-3) OR (-16)
055030,000468: # M:(-3) OR (-15)
055031,000469: 27,3573 40145 DLOAD BOV # (THE DLOAD IS SHARED WITH TFFELL)
055032,000470: 27,3574 00043 TFFX # NUM E: (-16) OR (-29) M:(-15) OR (-27)
055033,000471: 27,3575 57656 TFFELL # USE EQN FOR DELE GEQ 90, LEQ -90
055034,000472:
055035,000473: # OTHERWISE, CONTINUE FOR GENERAL CONIC FOR TFF EQN
055036,000474:
055037,000475: 27,3576 45471 DDV STADR
055038,000476: # DEN FROM PDL+0 E: (-3) OR (-16)
055039,000477: # M: (-3) OR (-15)
055040,000478: 27,3577 77732 STORE TFFTEM # Z SAVE FOR SIGN OF SDELF.
![]() |
Page 1276 |
055042,000480: # E: (-13) M: (-12)
055043,000481: 27,3600 63406 PUSH DSQ # Z TO PDL+0
055044,000482: 27,3601 41206 PUSH DMP # Z SQ TO PDL+2 E: (-26) M: (-24)
055045,000483: 27,3602 00035 TFFNP # LC P E: (-38+2NR) M: (-36+2NR)
055046,000484: 27,3603 75261 SL SIGN
055047,000485: 27,3604 20206 5
055048,000486: 27,3605 00045 TFFTEM # AFFIX SIGN FOR SDELF (ENTRY DISPLAY)
055049,000487: 27,3606 14045 STODL TFFTEM # P ZSQ E: (-59+2NR) M: (-55+2NR)
055050,000488: # (ARG IS USED IN TFF/TRIG)
055051,000489: # ZSQ FROM PDL+2 E: (-26) M: (-24)
055052,000490: 27,3607 41206 PUSH DMP # RESTORE PUSH LOC
055053,000491: 27,3610 00033 TFFALFA # ALFA E: (26-NR) M: (24-NR)
055054,000492: 27,3611 77657 SL*
055055,000493: 27,3612 20201 0,1 # X1=-NR
055056,000494: 27,3613 00043 STORE TFFX # X
055057,000495: 27,3614 41234 RTB DMP
055058,000496: 27,3615 57740 T(X) # POLY
055059,000497: # ZSQ FROM PDL+2 E: (-26) M: (-24)
055060,000498: 27,3616 44302 SR2 BDSU # 2 ZSQ T(X) E: (-29) M: (-27)
055061,000499: 27,3617 00023 RTERM # RTERM E: (-29) M: (-27)
055062,000500: 27,3620 41215 DAD DMP
055063,000501: 27,3621 00015 RMAG1 # E: (-29) M: (-27)
055064,000502: # Z FROM PDL+0 E: (-13) M: (-12)
055065,000503: 27,3622 51042 SR3 BPL # TFF SQRT(MU) E: (-45) M: (-42)
055066,000504: 27,3623 57644 ENDTFF # (NO PUSH UP)
055067,000505: 27,3624 75206 PUSH SIGN # TFF SQRT(MU) TO PDL+0
055068,000506: 27,3625 00017 TFFQ1 # Q1 FOR GONEPAST TEST
055069,000507: 27,3626 71244 BPL DLOAD # GONE PAST ?
055070,000508: 27,3627 57650 NEGTFF # YES. TFF < 0 .
055071,000509: 27,3630 00027 TFF1/ALF # 1/ALFA E: (-22-2NA) M: (-20-2NA)
055072,000510: 27,3631 51076 DCOMP BPL # ALFA > 0 ?
055073,000511: 27,3632 57650 NEGTFF # NO. TFF IS NEGATIVE.
055074,000512:
055075,000513: # CORRECT FOR ORBITAL PERIOD.
055076,000514:
055077,000515: 27,3633 77676 DCOMP # YES. CORRECT FOR ORB PERIOD.
055078,000516: 27,3634 56205 DMP DDV
055079,000517: 27,3635 17760 PI/16 # 2 PI (-5)
055080,000518: 27,3636 00031 TFFRTALF # SQRT(ALFA) E: (10+NA) M: (9+NA)
055081,000519: 27,3637 53657 SL* SL*
055082,000520: 27,3640 57602 0 -4,2 # X2=-NA
055083,000521: 27,3641 57602 0 -4,2
055084,000522: 27,3642 43257 SL* DAD
055085,000523: 27,3643 57576 0,2
055086,000524: # TFF SQRT(MU) FROM PDL+0 E:(-45) M:(-42)
055087,000525: 27,3644 40005 ENDTFF DMP BOV # TFF SQRT(MU) IN MPAC E:(-45) M:(-42)
055088,000526: 27,3645 00037 TFF/RTMU # E: (17) M: (14)
055089,000527: 27,3646 57654 MAXTFF # SET POSMAX IF OVFL.
055090,000528:
055091,000529: 27,3647 77616 DUMPTFF2 RVQ # RETURN TFF (-28) CS IN MPAC.
055092,000530:
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Page 1277 |
055094,000532: 27,3650 77745 NEGTFF DLOAD
055095,000533: # TFF SQRT(MU) FROM PDL+0, NEGATIVE.
055096,000534: 27,3651 77650 GOTO
055097,000535: 27,3652 57644 ENDTFF
055098,000536:
055099,000537: 27,3653 77745 MAXTFF1 DLOAD # RESET PDL
055100,000538: 27,3654 43545 MAXTFF DLOAD RVQ
055101,000539: 27,3655 17774 NEARONE
055102,000540:
055103,000541: # TIME OF FLIGHT ELLIPSE WHEN DEL (ECCENTRIC ANOM) GEQ 90 AND LEQ -90.
055104,000542:
055105,000543: # NUM FROM TFFX. E: (-16) OR (-29)
055106,000544: # M: (-15) OR (-27)
055107,000545: 27,3656 77712 TFFELL SL2 # NUM E:(-14) OR (-27) M:(-13) OR (-25)
055108,000546: 27,3657 41465 BDDV PUSH # TEMP SAVE D/N IN PDL+0
055109,000547: # DEN FROM PDL+0 E:(-3)/( 16) M:(-3)/(-15)
055110,000548: # N/D TO PDL+0 E: (11) M: (10)
055111,000549: 27,3660 45345 TFFEL1 DLOAD DSU # (ENTER WITH D/N=0 IN PDL+0)
055112,000550: 27,3661 00045 TFFTEM # Q2 E: (-16) M: (-15)
055113,000551: 27,3662 00017 TFFQ1 # Q1 E: (-16) M: (-15)
055114,000552: 27,3663 14013 STODL TFFDELQ # Q2-Q1 E: (-16) M: (-15)
055115,000553: # D/N FROM PDL+0
055116,000554: 27,3664 77626 STADR
055117,000555: 27,3665 77732 STORE TFFTEM # D/N E: (11) M: (10)
055118,000556: 27,3666 53605 DMP SL*
055119,000557: 27,3667 00027 TFF1/ALF # 1/ALFA E: (-22-2NA) M: (-20-2NA)
055120,000558: 27,3670 57576 0,2 # 1/ALFA Z E: (-11-NA) M: (-10-NA)
055121,000559: 27,3671 41206 PUSH DMP # TO PDL+0
055122,000560: 27,3672 00045 TFFTEM # 1/Z E: (11) M: (10)
055123,000561: 27,3673 41057 SL* BOVB
055124,000562: 27,3674 57576 0,2 # X2= -NA
055125,000563: 27,3675 31765 SIGNMPAC # IN CASE X= 1.0, CONTINUE
055126,000564: 27,3676 00043 STORE TFFX # X=1/ALFA ZSQ
055127,000565: 27,3677 41234 RTB DMP
055128,000566: 27,3700 57740 T(X) # POLY
055129,000567: 27,3701 00043 TFFX
055130,000568: 27,3702 45242 SR3 DSU
055131,000569: 27,3703 17766 DP2(-3)
055132,000570: 27,3704 41405 DMP PUSH # 2(X T(X)-1) /Z ALFA E: (-15-NA)
055133,000571: # M: (-14-NA)
055134,000572: # 1/ALFA Z FROM PDL+0 E: (-11-NA)
055135,000573: # M: (-10-NA)
055136,000574: 27,3705 41345 DLOAD DMP # GET SIGN FOR SDELF
055137,000575: 27,3706 00045 TFFTEM # 1/Z E: (11) M: (10)
055138,000576: 27,3707 00015 RMAG1 # E: (-29) M: (-27)
055139,000577: 27,3710 43312 SL2 DAD
055140,000578: 27,3711 00017 TFFQ1 # Q1 E: (-16) M: (-15)
055141,000579: 27,3712 14045 STODL TFFTEM # (Q1+R 1/Z) =SGN OF SDELF E:(-16) M:(-15
055142,000580: 27,3713 00035 TFFNP # LC P E: (-38+2NR) M: (-36+2NR)
055143,000581: 27,3714 53605 DMP SL* # CALC FOR ARG FOR TFF/TRIG.
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Page 1278 |
055145,000583: 27,3715 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
055146,000584: 27,3716 57575 1,2 # X2=-NA
055147,000585: 27,3717 53765 SIGN SL*
055148,000586: 27,3720 00045 TFFTEM # AFFIX SIGN FOR SDELF
055149,000587: 27,3721 57576 0,2
055150,000588: 27,3722 14045 STODL TFFTEM # P/ALFA E:(-59+2NR) M:(-55+2NR)
055151,000589: # (ARG FOR USE IN TFF/TRIG)
055152,000590: 27,3723 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
055153,000591: 27,3724 41366 SQRT DMP
055154,000592: 27,3725 17760 PI/16 # PI (-4)
055155,000593: 27,3726 77615 DAD
055156,000594: # 2(XT(X)-1)/Z ALFA FROM PDL E:(-15-NA)
055157,000595: # M:(-14-NA)
055158,000596: 27,3727 45257 SL* DSU
055159,000597: 27,3730 57577 0 -1,2
055160,000598: 27,3731 00013 TFFDELQ # Q2-Q1 E: (-16) M: (-15)
055161,000599: 27,3732 53605 DMP SL*
055162,000600: 27,3733 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
055163,000601: 27,3734 57601 0 -3,2
055164,000602: 27,3735 52057 SL* GOTO
055165,000603: 27,3736 57602 0 -4,2
055166,000604: 27,3737 57644 ENDTFF # TFF SQRT(MU) IN MPAC E:(-45) M:(-42)
055167,000605:
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Page 1279 |
055169,000607: # PROGRAM NAME: T(X) DATE: 01.17.67
055170,000608: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
055171,000609: # MOD BY: RR BAIRNSFATHER
055172,000610: # FUNCTIONAL DESCRIPTION: THE POLYNOMIAL T(X) IS USED BY TIME OF FLIGHT SUBROUTINES CALCTFF AND
055173,000611: # CALCTPER TO APPROXIMATE THE SERIES
055174,000612: # 2 3
055175,000613: # 1/3 -X/5 +X /7 -X /9 ...
055176,000614:
055177,000615: # WHERE X = ALFA Z Z IF ALFA Z Z LEQ 1
055178,000616: # X = 1/(ALFA Z Z) IF ALFA Z Z G 1
055179,000617:
055180,000618: # ALSO X IS NEG FOR HYPERBOLIC ORBITS
055181,000619: # X = 0 FOR PARABOLIC ORBITS
055182,000620: # X IS POSITIVE FOR ELLIPTIC ORBITS
055183,000621: # FOR FLIGHT 278, THE POLYNOMIAL T(X) IS FITTED OVER THE RANGE (0,+1) AND HAS A MAXIMUM
055184,000622: # DEVIATION FROM THE SERIES OF 2 E-5 (T(X) IS A CHEBYCHEV TYPE FIT AND WAS OBTAINED USING
055185,000623: # MAC PROGRAM AUTCURFIT294RRB AND IS VALID TO THE SAME TOLERANCE OVER THE RANGE (-.08,+1). )
055186,000624: # CALLING SEQUENCE: RTB
055187,000625: # T(X)
055188,000626: # C(MPAC) = X
055189,000627:
055190,000628: # SUBROUTINES CALLED: NONE
055191,000629: # NORMAL EXIT MODE: TC DANZIG
055192,000630: # ALARMS: NONE
055193,000631: # OUTPUT: C(MPAC) = T(X)
055194,000632: # ERASABLE INITIALIZATION REQUIRED:
055195,000633: # C(MPAC) = X
055196,000634: # DEBRIS: NONE
055197,000635:
055198,000636: 27,3740 07243 T(X) TC POLY
055199,000637: 27,3741 00004 DEC 4 B-14 # N-1
055200,000638: 27,3742 12525 12525 2DEC 3.333333333 E-1
055201,000639:
055202,000640: 27,3744 71463 57703 2DEC* -1.999819135 E-1*
055203,000641:
055204,000642: 27,3746 04423 17645 2DEC* 1.418148467 E-1*
055205,000643:
055206,000644: 27,3750 74604 43667 2DEC* -1.01310997 E-1*
055207,000645:
055208,000646: 27,3752 01626 37256 2DEC* 5.609004986 E-2*
055209,000647:
055210,000648: 27,3754 77404 52071 2DEC* -1.536156925 E-2*
055211,000649:
055212,000650: 27,3756 06102 ENDT(X) TC DANZIG
055213,000651:
055214,000652: 27,3757 27,3756 TCDANZIG = ENDT(X)
055215,000653:
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Page 1280 |
055217,000655: # TFF CONSTANTS
055218,000656:
055219,000657: 32,3716 BANK 32
055220,000658:
055221,000659: 27,2000 SETLOC TOF-FF1
055222,000660: 27,2000 BANK
055223,000661:
055224,000662: # NOTE _ NOTE _ ADJUSTED MUE FOR NEAR EARTH TRAJ.
055225,000663:
055226,000664: # MUE = 3.990 815 471 E10 M CUBE/CS SQ
055227,000665: # RTMUE = 1.997702549 E5 B-18* MODIFIED EARTH MU
055228,000666:
055229,000667: # NOTE _ NOTE _ ADJUSTED MUE FOR NEAR EARTH TRAJ.
055230,000668:
055231,000669: # MUM = 4.902 778 E8 M CUBE /CS SQ
055232,000670:
055233,000671: # RTMUM 2DEC* 2.21422176 E4 B-18*
055234,000672: 27,3757 06220 37553 PI/16 2DEC 3.141592653 B-4
055235,000673:
055236,000674: 27,3761 37777 37700 LIM(-22) 2OCT 3777737700 # 1.0 -B(-22)
055237,000675:
055238,000676: 27,3763 00000 00100 DP(-22) 2OCT 0000000100 # B(-22)
055239,000677:
055240,000678: 27,3765 04000 00000 DP2(-3) 2DEC 1 B-3
055241,000679:
055242,000680: 27,3767 02000 00000 DP2(-4) 2DEC 1 B-4 # 1/16
055243,000681:
055244,000682: # RPAD1 2DEC 6373338 B-29 M (-29) =20 909 901.57 FT
055245,000683:
055246,000684: 27,3771 23,2335 RPAD1 = RPAD
055247,000685:
055248,000686: 27,3771 00305 11205 R300K 2DEC 6464778 B-29 # (-29) M
055249,000687:
055250,000688: 27,3773 37777 37777 NEARONE 2DEC .999999999
055251,000689:
055252,000690: 27,3775 23,2504 TFFZEROS EQUALS HI6ZEROS
055253,000691: 27,3775 23,2474 TFF1/4 EQUALS HIDP1/4
055254,000692:
End of include-file TIME_OF_FREE_FALL.agc. Parent file is MAIN.agc