Source Code
059382,000001: # Copyright: Public domain.
059383,000002: # Filename: TIME_OF_FREE_FALL.agc
059384,000003: # Purpose: Part of the source code for Colossus 2A, AKA Comanche 055.
059385,000004: # It is part of the source code for the Command Module's (CM)
059386,000005: # Apollo Guidance Computer (AGC), for Apollo 11.
059387,000006: # Assembler: yaYUL
059388,000007: # Contact: Ron Burkey <info@sandroid.org>.
059389,000008: # Website: www.ibiblio.org/apollo.
059390,000009: # Pages: 1373-1388
059391,000010: # Mod history: 2009-05-10 SN (Sergio Navarro). Started adapting
059392,000011: # from the Colossus249/ file of the same
059393,000012: # name, using Comanche055 page images.
059394,000013:
059395,000014: # This source code has been transcribed or otherwise adapted from digitized
059396,000015: # images of a hardcopy from the MIT Museum. The digitization was performed
059397,000016: # by Paul Fjeld, and arranged for by Deborah Douglas of the Museum. Many
059398,000017: # thanks to both. The images (with suitable reduction in storage size and
059399,000018: # consequent reduction in image quality as well) are available online at
059400,000019: # www.ibiblio.org/apollo. If for some reason you find that the images are
059401,000020: # illegible, contact me at info@sandroid.org about getting access to the
059402,000021: # (much) higher-quality images which Paul actually created.
059403,000022:
059404,000023: # Notations on the hardcopy document read, in part:
059405,000024:
059406,000025: # Assemble revision 055 of AGC program Comanche by NASA
059407,000026: # 2021113-051. 10:28 APR. 1, 1969
059408,000027:
059409,000028: # This AGC program shall also be referred to as
059410,000029: # Colossus 2A
059411,000030:
059412,000031: # Page 1373
059413,000032: # THE TFF SUBROUTINES MAY BE USED IN EITHER EARTH OR MOON CENTERED COORDINATES. THE TFF ROUTINES NEVER
059414,000033: # KNOW WHICH ORIGIN APPLIES. IT IS THE USER WHO KNOWS, AND WHO SUPPLIES RONE, VONE, AND 1/SQRT(MU) AT THE
059415,000034: # APPROPIRATE SCALE LEVEL FOR THE PROPER PRIMARY BODY.
059416,000035:
059417,000036: # EARTH ORIGIN POSITION -29 METERS
059418,000037: # VELOCITY -7 METERS/CENTISECOND
059419,000038: # 1/SQRT(MU) +17 SQRT(CS SQ/METERS CUBED)
059420,000039:
059421,000040: # MOON ORIGIN POSITION -27 METERS
059422,000041: # VELOCITY -5 METERS/CENTISECONDS
059423,000042: # 1/SQRT(MU) +14 SQRT(CS SQ/METERS CUBED)
059424,000043:
059425,000044: # ALL DATA PROVIDED TO AND RECEIVED FROM ANY TFF SUBROUTINE WILL BE AT ONE OF THE LEVELS ABOVE. IN ALL CASES,
059426,000045: # THE FREE FALL TIME IS RETURNED IN CENTISECONDS AT (-28). PROGRAM TFF/CONIC WILL GENERATE VONE/RTMU AND
059427,000046: # LEAVE IT IN VONE' AT (+10) IF EARTH ORIGIN AND (+9) IF MOON ORIGIN.
059428,000047:
059429,000048: # THE USER MUST STORE THE STATE VECTOR IN RONE, VONE, AND MU IN THE FORM 1/SQRT(MU) IN TFF/RTMU
059430,000049: # AT THE PROPER SCALE BEFORE CALLING TFF/CONIC. SINCE RONE, VONE ARE IN THE EXTENDED VERB STORAGE AREA,
059431,000050: # THE USER MUST ALSO LOCK OUT THE EXTENDED VERBS, AND RELEASE THEM WHEN FINISHED.
059432,000051:
059433,000052: # PROGRAMS CALC/TFF AND CALC/TPER ASSUME THAT THE TERMINAL RADIUS IS LESS THAN THE PRESENT
059434,000053: # RADIUS. THIS RESTRICTION CAN BE REMOVED BY A 15 W CODING CHANGE, BUT AT PRESENT IT IS NOT DEEMED NECESSARY.
059435,000054:
059436,000055: # THE FOLLOWING ERASABLE QUANTITIES ARE USED BY THE TFF ROUTINES, AND ARE LOCATED IN THE PUSH LIST.
059437,000056:
059438,000057: # BELOW E: IS USED FOR EARTH ORIGIN SCALE
059439,000058: # M: IS USED FOR MOON ORIGIN SCALE
059440,000059:
059441,000060: # TFFSW = 119D # BIT1 0 = CALCTFF 1 = CALCTPER
059442,000061: 23,3772 TFFDELQ = 10D # Q2-Q1 E: (-16) M: (-15)
059443,000062: 23,3772 RMAG1 = 12D # ABVAL(RN) M E: (-29) M: (-27)
059444,000063: # RPER = 14D # PERIGEE RADIUS M E: (-29) M: (-27)
059445,000064: 23,3772 TFFQ1 = 14D # R.V / SQRT(MUE) E: (-16) M: (-15)
059446,000065: # SDELF/2 # SIN(THETA) /2
059447,000066: 23,3772 CDELF/2 = 14D # COS(THETA) /2
059448,000067: # RAPO = 16D # APOGEE RADIUS M E: (-29) M: (-27)
059449,000068: 23,3772 NRTERM = 16D # TERMINAL RADIUS M E: (-29+NR)
059450,000069: # M: (-27+NR)
059451,000070: 23,3772 RTERM = 18D # TERMINAL RADIUS M E: (-29) M: (-27)
059452,000071: 23,3772 TFFVSQ = 20D # -(V SQUARED/MU) 1/M E: (20) M: (18)
059453,000072: 23,3772 TFF1/ALF = 22D # SEMI MAJ AXIS M E: (-22-2 NA)
059454,000073: # M: (-20-2 NA)
059455,000074: 23,3772 TFFRTALF = 24D # SQRT(ALFA) E:(10+NA) M: (9+NA)
059456,000075: 23,3772 TFFALFA = 26D # ALFA 1/M E:(26-NR) M: (24-NR)
059457,000076: 23,3772 TFFNP = 28D # SEMI LATUS RECTUM M E: (-38+2 NR)
059458,000077: # M: (-36+2 NR)
059459,000078: 23,3772 TFF/RTMU = 30D # 1/SQRT(MU) E: (17) M: (14)
059460,000079: 23,3772 NRMAG = 32D # PRESENT RADIUS M E: (-29+NR)
059461,000080: # M: (-27+NR)
059462,000081: 23,3772 TFFX = 34D
059463,000082: 23,3772 TFFTEM = 36D # TEMPORARY
059464,000083: # Page 1374
059465,000084: # REGISTERS S1, S2 ARE UNTOUCED BY ANY TFF SUBROUTINE
059466,000085: # INDEX REGISTERS X1, X2 ARE USED BY ALL TFF SUBROUTINES. THEY ARE ESTAB-
059467,000086: # LISHED IN TFF/CONIC AND MUST BE PRESERVED BETWEEN CALLS TO SUBSEQUENT
059468,000087: # SUBROUTINES.
059469,000088: # -NR C(X1) = NORM COUNT OF RMAG
059470,000089: # -NA C(X2) = NORM COUNT OF SQRT(ABS(ALFA))
059471,000090:
059472,000091: # Page 1375
059473,000092: # SUBROUTINE NAME: TFFCONIC DATE: 01.29.67
059474,000093: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
059475,000094: # MOD BY: RR BAIRNSFATHER
059476,000095: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 11 APR 67
059477,000096: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 21 NOV 67 ADD MOON MU.
059478,000097: # MOD NO: 3 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
059479,000098:
059480,000099: # FUNCTIONAL DESCRIPTION: THIS SUBROUTINE IS CALLED TO COMPUTE THOSE CONIC PARAMETERS REQUIRED BY THE TFF
059481,000100: # SUBROUTINES AND TO ESTABLISH THEM IN THE PUSH LIST AREA. THE PARAMETERS ARE LISTED UNDER OUTPUT.
059482,000101: # THE EQUATIONS ARE:
059483,000102: # _ __ __
059484,000103: # H = RN*VN ANGULAR MOMENTUM
059485,000104: # _ _
059486,000105: # LCP = H.H / MU SEMI LATUS RECTUM
059487,000106: # __ __
059488,000107: # ALFA = 2/RN - VN.VN / MU RECIPROCAL SEMI MAJ AXIS, SIGNED
059489,000108:
059490,000109: # AND ALFA IS POS FOR ELLIPTIC ORBITS
059491,000110: # 0 FOR PARABOLIC ORBITS
059492,000111: # NEG FOR HYPERBOLIC ORBITS.
059493,000112: # SUBROUTINE ALSO COMPUTES AND SAVES RMAG.
059494,000113:
059495,000114: # CALLING SEQUENCE:
059496,000115: # TFFCONIC EXPECTS CALLER TO ENTER WITH CORRECT GRAVITATIONAL CONSTANT IN MPAC, IN THE FORM
059497,000116: # 1/SQRT(MU). THE PROGRAM WILL SAVE IN TFF/RTMU. THE SCALE IS DETERMINED BY WHETHER EARTH OR MOON
059498,000117: # ORIGIN IS USED. THE CALLER MUST LOCK OUT THE EXTENDED VERBS BEFORE PROVIDING STATE VECTOR IN RONE,
059499,000118: # VONE AT PROPER SCALE. THE EXTENDED VERBS MUST BE RESTORED WHEN THE CALLER IS FINISHED USING THE
059500,000119: # TFF ROUTINES.
059501,000120:
059502,000121: # ENTRY POINT TFFCONMU EXPECTS THAT TFF/RTMU IS ALREADY LOADED.
059503,000122:
059504,000123: # TO SPECIFY MU: DLOAD CALL # IF MU ALREADY STORED: CALL
059505,000124: # YOURMU # 1/RTMU E:(17) M:(14) TFFCONMU
059506,000125: # TFFCONIC
059507,000126: # PUSHLOC = PDL+0, ARBITRARY IF LEQ 18D
059508,000127:
059509,000128: # SUBROUTINES CALLED: NONE
059510,000129:
059511,000130: # NORMAL EXIT MODES: RVQ
059512,000131:
059513,000132: # ALARMS: NONE
059514,000133:
059515,000134: # OUTPUT: THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
059516,000135: # RMAG1 E:(-29) M:(-27) M RN, PRESENT RADIUS LENGTH.
059517,000136: # NRMAG E:(-29+NR) M RMAG, NORMALIZED
059518,000137: # M:(-27+NR)
059519,000138: # X1 -NR, NORM COUNT
059520,000139: # TFFNP E:(-38+2NR) M LCP, SEMI LATUS RECTUM, WEIGHTED BY NR. FOR VGAMCALC.
059521,000140: # M:(-36+2NR)
059522,000141: # TFF/RTMU E:(17) M:(14) 1/SQRT(MU)
059523,000142: # TFFVSQ E:(20) M:(18) 1/M -(V SQ/MU): PRESENT VELOCITY, NORMLIZED. FOR VGAMCALC
059524,000143: # TFFALFA E:(26-NR) 1/M ALFA, WEIGHTED BY NR
059525,000144: # M:(24-NR)
059526,000145: # TFFRTALF E:(10+NA) SQRT(ALFA), NORMALIZED
059527,000146: # M:(9+NA)
059528,000147: # Page 1376
059529,000148: # X2 -NA, NORM COUNT
059530,000149: # TFF1/ALF E:(-22-2NA) SIGNED SEMI MAJ AXIS, WEIGHTED BY NA
059531,000150: # M:(-20-2NA)
059532,000151: # PUSHLOC AT PDL+0
059533,000152:
059534,000153: # THE FOLLOWING IS STORED IN GENERAL ERASABLE
059535,000154: # VONE' E:(10) M:(9) V/RT(MU), NORMALIZED VELOCITY
059536,000155:
059537,000156: # ERASABLE INITIALIZATION REQUIRED:
059538,000157: # RONE E:(-29) M:(-27) M STATE VECTOR LEFT BY CALLER
059539,000158: # VONE E:(-7) M:(-5) M/CS STATE VECTOR LEFT BY CALLER
059540,000159: # TFF/RTMU E:(17) M:(14) 1/RT(CS SQ/M CUBE) IF ENTER VIA TFFCONMU.
059541,000160:
059542,000161: # DEBRIS: QPRET PDL+0 ... PDL+3
059543,000162:
059544,000163: 33,3776 BANK 33
059545,000164: 27,2000 SETLOC TOF-FF
059546,000165: 27,2000 BANK
059547,000166:
059548,000167: 27,2757 COUNT* $$/TFF
059549,000168:
059550,000169: 27,2757 00037 TFFCONIC STORE TFF/RTMU # 1/SQRT(MU) E:(17) M:(14)
059551,000170:
059552,000171: 27,2760 53575 TFFCONMU VLOAD UNIT # COME HERE WITH TFFRTMU LOADED.
059553,000172: 27,2761 02327 RONE # SAVED RN. M E:(-29) M:(-27)
059554,000173: 27,2762 77725 PDDL # UR/2 TO PDL+0, +5
059555,000174: 27,2763 00045 36D # MAGNITUDE
059556,000175: 27,2764 00015 STORE RMAG1 # M E:(-29) M:(-27)
059557,000176:
059558,000177: 27,2765 77701 NORM
059559,000178: 27,2766 00047 X1 # -NR
059560,000179: 27,2767 24041 STOVL NRMAG # RMAG M E:(-29+NR) M:(-27+NR)
059561,000180: 27,2770 02335 VONE # SAVED VN. M/CS E:(-7) M:(-5)
059562,000181: 27,2771 77761 VXSC
059563,000182: 27,2772 00037 TFF/RTMU # E:(17) M:(14)
059564,000183: 27,2773 02372 STORE VONE' # VN/SQRT(MU) E:(10) M:(9)
059565,000184:
059566,000185: 27,2774 47361 VXSC VXV
059567,000186: 27,2775 00041 NRMAG # E:(-29+NR) M:(-27+NR)
059568,000187: # UR/2 FROM PDL
059569,000188: 27,2776 47572 VSL1 VSQ # BEFORE: E:(-19+NR) M:(-18+NR)
059570,000189: 27,2777 14035 STODL TFFNP # LC P M E:(-38+2NR) M:(-36+2NR)
059571,000190: # SAVE ALSO FOR VGAMCALC
059572,000191: 27,3000 15325 TFF1/4
059573,000192: 27,3001 63271 DDV PDVL # (2/RMAG) 1/M E:(26-NR) M:(24-NR)
059574,000193: 27,3002 00041 NRMAG # RMAG M E:(-29+NR) M:(-27+NR)
059575,000194: 27,3003 02372 VONE' # SAVED VN. E:(10) M:(9)
059576,000195: 27,3004 57436 VSQ DCOMP # KEEP MPAC+2 HONEST FOR SQRT.
059577,000196: 27,3005 00025 STORE TFFVSQ # -(V SQ/MU) E:(20) M:(18)
059578,000197: # SAVE FOR VGAMCALC
059579,000198: 27,3006 43257 SR* DAD
059580,000199: # Page 1377
059581,000200: 27,3007 20573 0 -6,1 # GET -VSQ/MU E:(26-NR) M:(24-NR)
059582,000201: 27,3010 77626 STADR
059583,000202: # 2/RMAG FROM PDL+2
059584,000203: 27,3011 77744 STORE TFFALFA # ALFA 1/M E:(26-NR) M:(24-NR)
059585,000204: 27,3012 41457 SL* PUSH # TEMP SAVE ALFA E:(20) M:(18)
059586,000205: 27,3013 20173 0 -6,1
059587,000206: 27,3014 75446 ABS SQRT # E:(10) M:(9)
059588,000207: 27,3015 77701 NORM
059589,000208: 27,3016 00050 X2 # X2 = -NA
059590,000209: 27,3017 00031 STORE TFFRTALF # SQRT( ABS(ALFA) ) E:(10+NA) M:(9+NA)
059591,000210: 27,3020 75316 DSQ SIGN # NOT SO ACCURATE, BUT OK
059592,000211: # ALFA FROM PDL+2 E:(20) M:(18)
059593,000212: 27,3021 55254 BZE BDDV # SET 1/ALFA =0, TO SHOW SMALL ALFA
059594,000213: 27,3022 57024 +2
059595,000214: 27,3023 15325 TFF1/4
059596,000215: 27,3024 00027 +2 STORE TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
059597,000216: 27,3025 77616 DUMPCNIC RVQ
059598,000217: # 39 W
059599,000218: # Page 1378
059600,000219: # SUBROUTINE NAME: TFFRP/RA DATE: 01.17.67
059601,000220: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
059602,000221: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 11 APR 67
059603,000222: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
059604,000223: # ALSO IMPROVE ACCURACY OF RAPO.
059605,000224:
059606,000225: # FUNCTIONAL DESCRIPTION: USED BY CALCTPER AND TFF DISPLAYS TO CALCULATE PERIGEE RADIUS AND ALSO
059607,000226: # APOGEE RADIUS FOR A GENERAL CONIC.
059608,000227: # PROGRAM GIVES PERIGEE RADIUS AS APOGEE RADIUS IS GIVEN BY
059609,000228: # RP = P/(1+E) RA = (1+E) / ALFA
059610,000229: # WHERE 2
059611,000230: # E = 1 - P ALFA
059612,000231: # IF RA IS NEGATIVE OR SHOWS DIVIDE OVERFLOW, THEN RA = POSMAX BECAUSE
059613,000232: # 1. APOGEE RADIUS IS NOT MEANINGFUL FOR HYPERBOLA
059614,000233: # 2. APOGEE RADIUS IS NOT DEFINED FOR PARABOLA
059615,000234: # 3. APOGEE RADIUS EXCEEDS THE SCALING FOR ELLIPSE.
059616,000235:
059617,000236: # THIS SUBROUTINE REQUIRED THE SIGNED RECIPROCAL SEMI MAJ AXIS, ALFA, AND SEMI LATUS RECTUM AS DATA.
059618,000237:
059619,000238: # CALLING SEQUENCE: CALL
059620,000239: # TFFRP/RA
059621,000240: # PUSHLOC = PDL+0, ARBITRARY IF LEQ 10D
059622,000241: # C(MPAC) UNSPECIFIED
059623,000242:
059624,000243: # SUBROUTINES CALLED: NONE
059625,000244:
059626,000245: # NORMAL EXIT MODE: RVQ
059627,000246: # IF ELLIPSE, WITHIN NORMAL SCALING, RAPO IS CORRECT.
059628,000247: # OTHERWISE, RAPO = POSMAX.
059629,000248:
059630,000249: # ALARMS: NONE
059631,000250:
059632,000251: # OUTPUT: STORED IN PUSH LIST AREA. SCALE OF OUTPUT AGREES WITH DATA SUPPLIED TO TFF/CONIC.
059633,000252: # RPER E:(-29) M:(-27) M PERIGEE RADIUS DESTROYED BY CALCTFF/CALCTPER, TFFTRIG.
059634,000253: # RAPO E:(-29) M:(-27) M APOGEE RADIUS WILL BE DESTROYED BY CALCTFF/CALCTPER
059635,000254: # PUSHLOC AT PDL+0
059636,000255:
059637,000256: # ERASABLE INITIALIZATION REQUIRED:
059638,000257: # TFFALFA E:(26-NR) M 1/SEMI MAJ AXIS LEFT BY TFFCONIC
059639,000258: # M:(24-NR)
059640,000259: # TFFNP E:(-38+2NR) M LC P, SEMI LATUS RECTUM LEFT BY TFFCONIC
059641,000260: # M:(-36+2NR)
059642,000261: # X1 -NR, NORM COUNT OF RMAG LEFT BY TFFCONIC
059643,000262: # X2 -NA, NORM COUNT OF ALFA LEFT BY TFFCONIC
059644,000263:
059645,000264: # DEBRIS: QPRET, PDL+0 ... PDL+1
059646,000265:
059647,000266: # Page 1379
059648,000267: 27,3026 RAPO = 16D # APOGEE RADIUS M E:(-29) M:(-27)
059649,000268: 27,3026 RPER = 14D # PERIGEE RADIUS M E:(-29) M:(-27)
059650,000269:
059651,000270: 27,3026 41345 TFFRP/RA DLOAD DMP
059652,000271: 27,3027 00033 TFFALFA # ALFA 1/M E:(26-NR) M:(24-NR)
059653,000272: 27,3030 00035 TFFNP # LC P M E:(-38+2NR) M:(-36+2NR)
059654,000273: 27,3031 57457 SR* DCOMP # ALFA P (-12+NR)
059655,000274: 27,3032 20571 0 -8D,1 # ALFA P (-4)
059656,000275: 27,3033 51415 DAD ABS # (DCOMP GIVES VALID TP RESULT FOR SQRT)
059657,000276: # (ABS PROTECTS SQRT IF E IS VERY NEAR 0)
059658,000277: 27,3034 17366 DP2(-4)
059659,000278: 27,3035 43366 SQRT DAD # E SQ = (1- P ALFA) (-4)
059660,000279: 27,3036 15325 TFF1/4
059661,000280: 27,3037 55206 PUSH BDDV # (1+E) (-2) TO PDL+0
059662,000281: 27,3040 00035 TFFNP # LCP M E:(-38+2NR) M:(-36+2NR)
059663,000282: 27,3041 53657 SR* SR* # (DOES SR THEN SL TO AVOID OVFL)
059664,000283: 27,3042 20601 0,1 # X1=-NR
059665,000284: 27,3043 20572 0 -7,1 # (EFFECTIVE SL)
059666,000285: 27,3044 14017 STODL RPER # PERIGEE RADIUS M E:(-29) M:(-27)
059667,000286: # (1+E) (-2) FROM PDL+0
059668,000287: 27,3045 41005 DMP BOVB
059669,000288: 27,3046 00027 TFF1/ALF # E:(-22-2NA) M:(-20-2NA)
059670,000289: 27,3047 57352 TCDANZIG # CLEAR OVFIND, IF ON.
059671,000290: 27,3050 53654 BZE SL*
059672,000291: 27,3051 57060 MAXRA # SET POSMAX IF ALFA=0
059673,000292: 27,3052 57603 0 -5,2 # -5+NA
059674,000293: 27,3053 40057 SL* BOV
059675,000294: 27,3054 57576 0,2
059676,000295: 27,3055 57060 MAXRA # SET POSMAX IF OVFL.
059677,000296: 27,3056 77644 BPL # CONTINUE WITH VALID RAPO.
059678,000297: 27,3057 57062 +3
059679,000298: 27,3060 77745 MAXRA DLOAD # RAPO CALC IS NOT VALID. SET RAPO =
059680,000299: 27,3061 17372 NEARONE # POSMAX AS A TAG.
059681,000300: 27,3062 00021 +3 STORE RAPO # APOGEE RADIUS M E:(-29) M:(-27)
059682,000301: 27,3063 77616 DUMPRPRA RVQ
059683,000302: # 30 W
059684,000303: # Page 1380
059685,000304: # SUBROUTINE NAME: CALCTPER / CALCTFF DATE: 01.29.67
059686,000305: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
059687,000306: # MOD BY: RR BAIRNSFATHER
059688,000307: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 67
059689,000308: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 14 APR 67
059690,000309: # MOD BY: 3 MOD BY: RR BAIRNSFATHER DATE: 8 JUL 67 NEAR EARTH MUE AND NEG TFF (GONEPAST)
059691,000310: # MOD BY: 4 MOD BY: RR BAIRNSFATHER DATE: 21 NOV 67 ADD VARIABLE MU.
059692,000311: # MOD BY: 5 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
059693,000312:
059694,000313: # FUNCTIONAL DESCRIPTION: PROGRAM CALCULATES THE FREE-FALL TIME OF FLIGHT FROM PRESENT POSITION RN AND
059695,000314: # VELOCITY VN TO A RADIUS LENGTH SPECIFIED BY RTERM, SUPPLIED BY THE USER. THE POSITION VECTOR
059696,000315: # RN MAY BE ON EITHER SIDE OF THE CONIC, BUT RTERM IS CONSIDERED ON THE INBOUND SIDE.
059697,000316: # THE EQUATIONS ARE:
059698,000317:
059699,000318: # Q2 = -SQRT(RTERM (2-RTERM ALFA) - LCP) (INBOUND SIDE) LEQ +- LCE/SQRT(ALFA)
059700,000319: # __ __
059701,000320: # Q1 = RN.VN / SQRT(MU) LEQ +- LCE/SQRT(ALFA)
059702,000321:
059703,000322: # Z = NUM / DEN LEQ +- 1/SQRT(ALFA)
059704,000323:
059705,000324: # WHERE, IF INBOUND
059706,000325: # NUM = RTERM -RN LEQ +- 2 LCE/ALFA
059707,000326: # DEN = Q2+Q1 LEQ +- 2 LCE/SQRT(ALFA)
059708,000327:
059709,000328: # AND, IF OUTBOUND
059710,000329: # NUM = Q2-Q1 LEQ +- 2 LCE/SQRT(ALFA)
059711,000330: # DEN = 2 - ALFA (RTERM + RN). LEQ +- 2 LCE
059712,000331:
059713,000332: # IF ALFA ZZ < 1.0 (FOR ALL CONICS EXCEPT ELLIPSES HAVING ABS(DEL ECC ANOM) G 90 DEG)
059714,000333: # THEN X = ALFA Z Z
059715,000334: # AND TFF = (RTERM +RN -2 ZZ T(X) ) Z/SQRT(MU)
059716,000335: # EXCEPT IF ALFA PNZ, AND IF TFF NEG,
059717,000336: # THEN TFF = 2 PI /(ALFA SQRT(ALFA)) + TFF
059718,000337: # OR IF ALFA ZZ GEQ 1.0 (FOR ELLIPSES HAVING ABS(DEL ECC ANOM) GEQ 90 DEG)
059719,000338: # THEN X = 1/ALFA Z Z
059720,000339: # AND TFF = (PI/SQRT(ALFA) -Q2 +Q1 +2(X T(X) -1) /ALFA Z) /ALFA SQRT(MU)
059721,000340: # WHERE T(X) IS A POLYNOMIAL APPROXIMATION TO THE SERIES
059722,000341: # 2 3 2
059723,000342: # 1/3 - X/5 + X /7 - X /8 ... (X < 1.0)
059724,000343:
059725,000344: # CALLING SEQUENC: TIME TO RTERM TIME TO PERIGEE
059726,000345: # CALL CALL
059727,000346: # CALCTFF CALCTPER
059728,000347: # C(MPAC) = TERMNL RAD M C(MPAC) = PERIGEE RAD M
059729,000348: # FOR EITHER, E:(-29) M:(-27)
059730,000349: # FOR EITHER, PUSHLOC = PDL+0, ARBITRARY IF LEQ 8D.
059731,000350: # Page 1381
059732,000351:
059733,000352: # SUBROUTINES CALLED: T(X), VIA RTB
059734,000353:
059735,000354: # NORMAL EXIT MODE: RVQ
059736,000355: # HOWEVER, PROGRAM EXITS WITH ONE OF THE FOLLOWING VALUES FOR TFF (-28) CS IN MPAC. USER MUST STORE.
059737,000356: # A. TFF = FLIGHT TIME. NORMAL CASE FOR POSITIVE FLIGHT TIME LESS THAN ONE ORBITAL PERIOD.
059738,000357: # B. (THIS OPTION IS NO LONGER USED.)
059739,000358: # C. TFF = POSMAX. THIS INDICATES THAT THE CONIC FROM THE PRESENT POSITION WILL NOT RETURN TO
059740,000359: # THE SPECIFIED ALTITUDE. ALSO INDICATES OUTBOUND PARABOLA OR HYPERBOLA.
059741,000360:
059742,000361: # OUTPUT: C(MPAC) (-28) CS TIME OF FLIGHT, OR TIME TO PERIGEE
059743,000362: # TFFX (0) X, LEFT FOR ENTRY DISPLAY TFF ROUTINES
059744,000363: # NRTERM E:(-29+NR) M RTERM, WEIGHTED BY NR LEFT FOR ENTRY DISPLAY TFF ROUTINES
059745,000364: # M:(-27+NR)
059746,000365: # TFFTEM E:(-59+2NR) LCP Z Z SGN(SDELF) LEFT FOR ENTRY DISPLAY TFF ROUTINES
059747,000366: # M:(-55+2NR) LCP /ALFA SGN(SDELF) LEFT FOR ENTRY DISPLAY TFF ROUTINES
059748,000367: # NOTE: TFFTEM = PDL 36D AND WILL BE DESTROYED BY .:UNIT:.
059749,000368: # RMAG1 E:(-29) M:(-27) PDL 12 NOT TOUCHED.
059750,000369: # TFFQ1 E:(-16) M:(-15) PDL 14D
059751,000370: # TFFDELQ E:(-16) M:(-15) PDL 10D
059752,000371: # PUSHLOC AT PDL+0
059753,000372:
059754,000373: # ERASABLE INITIALIZATION REQUIRED:
059755,000374: # RONE E:(-29) M:(-27) M STATE VECTOR LEFT BY USER
059756,000375: # VONE' E:(+10) M:(+9) VN/SQRT(NU) LEFT BY TFF/CONIC
059757,000376: # RMAG1 E:(-29) M:(-27) PRESENT RADIUS, M LEFT BY TFFCONIC
059758,000377: # C(MPAC) E:(-29) M:(-27) RTERM, TERMINAL RADIUS LENGTH, M LEFT BY USER
059759,000378:
059760,000379: # THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
059761,000380: # TFF/RTMU E:(17) M:(14) 1/SQRT(MU) LEFT BY TFFCONIC.
059762,000381: # NRMAG E:(-29+NR) M RMAG, NORMALIZED LEFT BY TFFCONIC
059763,000382: # M:(-27+NR)
059764,000383: # X1 -NR, NORM COUNT LEFT BY TFFCONIC
059765,000384: # TFFNP E:(-38+2NR) M LCP, SEMI LATUS RECTUM, WEIGHT NR LEFT BY TFFCONIC
059766,000385: # M:(-36+2N4)
059767,000386: # TFFALFA E:(26-NR) 1/M ALFA, WEIGHT NR LEFT BY TFFCONIC
059768,000387: # M:(24-NR)
059769,000388: # TFFRTALF E:(10+NA) SQRT(ALFA), NORMALIZED LEFT BY TFFCONIC
059770,000389: # M:(9+NA)
059771,000390: # X2 -NA, NORM COUNT LEFT BY TFFCONIC
059772,000391: # TFF1/ALF E:(-22-2NA) SIGNED SEMIMAJ AXIS, WEIGHTED BY NA LEFT BY TFFCONIC
059773,000392: # M:(-20-2NA)
059774,000393:
059775,000394: # DEBRIS: QPRET, PDL+0 ... PDL+3
059776,000395: # RTERM E:(-29) M(-27) RTERM, TERMINAL RADIUS LENGTH
059777,000396: # RAPO E:(-29) M(-27) PDL 16D (=NRTERM)
059778,000397: # RPER E:(-29) M(-27) PDL 14D (=TFFQ1)
059779,000398:
059780,000399: # Page 1382
059781,000400: 27,3064 77614 CALCTPER SETGO # ENTER WITH RPER IN MPAC
059782,000401: 27,3065 03436 TFFSW
059783,000402: 27,3066 57071 +3
059784,000403: 27,3067 77614 CALCTFF CLEAR # ENTER WITH RTERM IN MPAC
059785,000404: 27,3070 03676 TFFSW
059786,000405: 27,3071 00023 +3 STORE RTERM # E:(-29) M:(-27)
059787,000406: 27,3072 77657 SL*
059788,000407: 27,3073 20201 0,1 # X1=-NR
059789,000408: 27,3074 00021 STORE NRTERM # RTERM E:(-29+NR) M:(-27+NR)
059790,000409: 27,3075 44205 DMP BDSU
059791,000410: 27,3076 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
059792,000411: 27,3077 15325 TFF1/4
059793,000412: 27,3100 41206 PUSH DMP # (2-ALFA RTERM) (-3) TO PDL+0
059794,000413: 27,3101 00021 NRTERM # E:(-29+NR) M:(-27+NR)
059795,000414: 27,3102 53725 PDDL SR* # RTERM(2-ALFA RTERM) TO PDL+2
059796,000415: # E:(-32+NR) M:(-30+NR)
059797,000416: 27,3103 00035 TFFNP # LC P E:(-38+2NR) M:(-36+2NR)
059798,000417: 27,3104 20573 0 -6,1 # X1 = -NR
059799,000418: 27,3105 43276 DCOMP DAD # DUE TO SHIFTS, KEEP PRECISION FOR SQRT
059800,000419: # RTERM(2-ALFA RTERM) FROM PDL +2
059801,000420: # E:(-32+NR) M:(-30+NR)
059802,000421: 27,3106 77657 SR* # LEAVE E:(-32) M:(-30)
059803,000422: 27,3107 20601 0,1 # X1 = -NR
059804,000423: 27,3110 71214 BOFF DLOAD # CHECK TFF /TPER SWITCH
059805,000424: 27,3111 03756 TFFSW
059806,000425: 27,3112 57114 +2 # IF TFF, CONTINUE
059807,000426: 27,3113 15335 TFFZEROS # IF TPER, SET Q2 = 0
059808,000427: 27,3114 75440 +2 BMN SQRT # E:(-16) M:(-15)
059809,000428: 27,3115 57247 MAXTFF1 # NO FREE FALL CONIC TO RTERM FROM HERE
059810,000429: # RESET PDL, SET TFF=POSMAX, AND EXIT.
059811,000430:
059812,000431: 27,3116 41076 DCOMP BOVB # RT IS ON INBOUND SIDE. ASSURE OVFIND=0
059813,000432: 27,3117 57352 TCDANZIG # ANY PORT IN A STORM.
059814,000433: 27,3120 24045 STOVL TFFTEM # Q2 E:(-16) M:(-15)
059815,000434: 27,3121 02372 VONE' # VN/SQRT(MU) E:(10) M:(9)
059816,000435: 27,3122 52441 DOT SL3
059817,000436: 27,3123 02327 RONE # SAVED RN. E:(-29) M:(-27)
059818,000437: 27,3124 00017 STORE TFFQ1 # Q1, SAVE FOR GONEPAST TEST.
059819,000438: # E:(-16) M:(-15)
059820,000439: 27,3125 44240 BMN BDSU
059821,000440: 27,3126 57147 INBOUND # USE ALTERNATE Z
059822,000441: 27,3127 00045 TFFTEM # Q2 E:(-16) M:(-15)
059823,000442:
059824,000443: # OUTBOUND Z CALC CONTINUES HERE
059825,000444:
059826,000445: 27,3130 14043 STODL TFFX # NUM=Q2-Q1 E:(-16) M:(-15)
059827,000446: 27,3131 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
059828,000447: 27,3132 44205 DMP BDSU
059829,000448: # Page 1383
059830,000449: 27,3133 00041 NRMAG # RMAG E:(-29+NR) M:(-27+NR)
059831,000450: # (2-RTERM ALFA) (-3) FROM PDL+0
059832,000451: 27,3134 51406 SAVEDEN PUSH ABS # DEN TO PDL+0 E:(-3) OR (-16)
059833,000452: # M:(-3) OR (-15)
059834,000453: 27,3135 40015 DAD BOV # INDETERMINANCY TEST
059835,000454: 27,3136 17360 LIM(-22) # =1.0-B(-22)
059836,000455: 27,3137 57160 TFFXTEST # GO IF DEN >/= B(-22)
059837,000456: 27,3140 65345 DLOAD PDDL # SET DEN=0 OTHERWISE
059838,000457: 27,3141 15335 TFFZEROS
059839,000458: # XCH ZERO WITH PDL+0
059840,000459: 27,3142 57545 DLOAD DCOMP
059841,000460: 27,3143 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
059842,000461: 27,3144 71240 BMN DLOAD # FOR TPER: Z INDET AT DELE/2=0 AND 90.
059843,000462: 27,3145 57254 TFFEL1 # ASSUME 90, AND LEAVE 0 IN PDL: 1/Z=D/N
059844,000463:
059845,000464: # Z INDET. AT PERIGEE FOR PARAB OR HYPERB.
059846,000465: 27,3146 77616 DUMPTFF1 RVQ # RETURN TFF =0
059847,000466:
059848,000467: # INBOUND Z CALC CONTINUES HERE
059849,000468:
059850,000469: 27,3147 77745 INBOUND DLOAD # RESET PDL+0
059851,000470: 27,3150 45345 DLOAD DSU # ALTERNATE Z CALC
059852,000471: 27,3151 00023 RTERM # E:(-29) M:(-27)
059853,000472: 27,3152 00015 RMAG1 # E:(-29) M:(-27)
059854,000473: 27,3153 14043 STODL TFFX # NUM=RTERM-RN E:(-29) M:(-27)
059855,000474: 27,3154 00045 TFFTEM # Q2 E:(-16) M:(-15)
059856,000475: 27,3155 52015 DAD GOTO
059857,000476: 27,3156 00017 TFFQ1 # Q1 E:(-16) M:(-15)
059858,000477: 27,3157 57134 SAVEDEN # DEN = Q2+Q1 E:(-16) M:(-15)
059859,000478:
059860,000479: 27,3160 65215 TFFXTEST DAD PDDL # (ABS(DEN) TO PDL+2) E:(-3) OR (-16)
059861,000480: # M:(-3) OR (-15)
059862,000481: 27,3161 17362 DP(-22) # RESTORE ABS(DEN) TO MPAC
059863,000482: 27,3162 00043 TFFX # NUM E:(-16) OR (-29) M:(-15) OR (-27)
059864,000483: 27,3163 53605 DMP SR*
059865,000484: 27,3164 00031 TFFRTALF # SQRT(ALFA) E:(10+NA) M:(9+NA)
059866,000485: 27,3165 57201 0 -3,2 # X2=-NA
059867,000486: 27,3166 77671 DDV # C(MPAC) =NUM SQRT(ALFA) E:(-3) OR (-16)
059868,000487: # M:(-3) OR (-15)
059869,000488: # ABS(DEN) FROM PDL+2 E:(-3) OR (-16)
059870,000489: # M:(-3) OR (-15)
059871,000490: 27,3167 40145 DLOAD BOV # (THE DLOAD IS SHARED WITH TFFELL)
059872,000491: 27,3170 00043 TFFX # NUM E:(-16) OR (-29) M:(-15) OR (-27)
059873,000492: 27,3171 57252 TFFELL # USE EQN FOR DELE GEQ 90, LEQ -90
059874,000493:
059875,000494: # OTHERWISE, CONTINUE FOR GENERAL CONIC FOR TFF EQN
059876,000495:
059877,000496: 27,3172 45471 DDV STADR
059878,000497: # DEN FROM PDL+0 E:(-3) OR (-16)
059879,000498: # M:(-3) OR (-15)
059880,000499: 27,3173 77732 STORE TFFTEM # Z SAVE FOR SIGN OF SDELF.
059881,000500: # Page 1384
059882,000501: # E:(-13) M:(-12)
059883,000502: 27,3174 63406 PUSH DSQ # Z TO PDL+0
059884,000503: 27,3175 41206 PUSH DMP # Z SQ TO PDL+2 E:(-26) M:(-24)
059885,000504: 27,3176 00035 TFFNP # LC P E:(-38+2NR) M:(-36+NR)
059886,000505: 27,3177 75261 SL SIGN
059887,000506: 27,3200 20206 5
059888,000507: 27,3201 00045 TFFTEM # AFFIX SIGN FOR SDELF (ENTRY DISPLAY)
059889,000508: 27,3202 14045 STODL TFFTEM # P ZSQ E:(-59+2NR) M:(-55+2NR)
059890,000509: # (ARG IS USED IN TFF/TRIG)
059891,000510: # ZSQ FROM PDL+2 E:(-26) M:(-24)
059892,000511: 27,3203 41206 PUSH DMP # RESTORE PUSH LOC
059893,000512: 27,3204 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
059894,000513: 27,3205 77657 SL*
059895,000514: 27,3206 20201 0,1 # X1=-NR
059896,000515: 27,3207 00043 STORE TFFX # X
059897,000516: 27,3210 41234 RTB DMP
059898,000517: 27,3211 57334 T(X) # POLY
059899,000518: # ZSQ FROM PDL+2 E:(-26) M:(-24)
059900,000519: 27,3212 44302 SR2 BDSU # 2 ZSQ T(X) E:(-29) M:(-27)
059901,000520: 27,3213 00023 RTERM # RTERM E:(-29) M:(-27)
059902,000521: 27,3214 41215 DAD DMP
059903,000522: 27,3215 00015 RMAG1 # E:(-29) M:(-27)
059904,000523: # Z FROM PDL+0 E:(-13) M:(-12)
059905,000524: 27,3216 51042 SR3 BPL # TFF SQRT(MU) E:(-45) M:(-42)
059906,000525: 27,3217 57240 ENDTFF # (NO PUSH UP)
059907,000526: 27,3220 75206 PUSH SIGN # TFF SQRT(MU) TO PDL+0
059908,000527: 27,3221 00017 TFFQ1 # Q1 FOR GONEPAST TEST
059909,000528: 27,3222 71244 BPL DLOAD # GONE PAST ?
059910,000529: 27,3223 57244 NEGTFF # YES. TFF < 0.
059911,000530: 27,3224 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
059912,000531: 27,3225 51076 DCOMP BPL # ALFA > 0 ?
059913,000532: 27,3226 57244 NEGTFF # NO. TFF IS NEGATIVE.
059914,000533:
059915,000534: # CORRECT FOR ORBITAL PERIOD.
059916,000535:
059917,000536: 27,3227 77676 DCOMP # YES. CORRECT FOR ORB PERIOD.
059918,000537: 27,3230 56205 DMP DDV
059919,000538: 27,3231 17356 PI/16 # 2 PI (-5)
059920,000539: 27,3232 00031 TFFRTALF # SQRT(ALFA) E:(10+NA) M:(9+NA)
059921,000540: 27,3233 53657 SL* SL*
059922,000541: 27,3234 57602 0 -4,2 # X2=-NA
059923,000542: 27,3235 57602 0 -4,2
059924,000543: 27,3236 43257 SL* DAD
059925,000544: 27,3237 57576 0,2
059926,000545: # TFF SQRT(MU) FROM PDL+0 E:(-45) M:(-42)
059927,000546: 27,3240 40005 ENDTFF DMP BOV # TFF SQRT(MU) IN MPAC E:(-45) M:(-42)
059928,000547: 27,3241 00037 TFF/RTMU # E:(17) M:(14)
059929,000548: 27,3242 57250 MAXTFF # SET POSMAX IN OVFL.
059930,000549:
059931,000550: 27,3243 77616 DUMPTFF2 RVQ # RETURN TFF (-28) CS IN MPAC.
059932,000551:
059933,000552: # Page 1385
059934,000553: 27,3244 77745 NEGTFF DLOAD
059935,000554: # TFF SQRT(MU) FROM PDL+0, NEGATIVE.
059936,000555: 27,3245 77650 GOTO
059937,000556: 27,3246 57240 ENDTFF
059938,000557:
059939,000558: 27,3247 77745 MAXTFF1 DLOAD # RESET PDL
059940,000559: 27,3250 43545 MAXTFF DLOAD RVQ
059941,000560: 27,3251 17372 NEARONE
059942,000561:
059943,000562: # TIME OF FLIGHT ELLIPSE WHEN DEL (ECCENTRIC ANOM) GEQ 90 AND LEQ -90.
059944,000563:
059945,000564: # NUM FROM TFFX. E:(-16) OR (-29)
059946,000565: # M:(-15) OR (-27)
059947,000566: 27,3252 77712 TFFELL SL2 # NUM E:(-14) OR (-27) M:(-13) OR (-25)
059948,000567: 27,3253 41465 BDDV PUSH # TEMP SAVE D/N IN PDL+0
059949,000568: # DEN FROM PDL+0 E:(-3)/(-16) M:(-3)/(-15)
059950,000569: # N/D TO PDL+0 E:(11) M:(10)
059951,000570: 27,3254 45345 TFFEL1 DLOAD DSU # (ENTER WITH D/N=0 IN PDL+0)
059952,000571: 27,3255 00045 TFFTEM # Q2 E:(-16) M:(-15)
059953,000572: 27,3256 00017 TFFQ1 # Q1 E:(-16) M:(-15)
059954,000573: 27,3257 14013 STODL TFFDELQ # Q2-Q1 E:(-16) M:(-15)
059955,000574: # D/N FROM PDL+0
059956,000575: 27,3260 77626 STADR
059957,000576: 27,3261 77732 STORE TFFTEM # D/N E:(11) M:(10)
059958,000577: 27,3262 53605 DMP SL*
059959,000578: 27,3263 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
059960,000579: 27,3264 57576 0,2 # 1/ALFA Z E:(-11-NA) M:(-10-NA)
059961,000580: 27,3265 41206 PUSH DMP # TO PDL+0
059962,000581: 27,3266 00045 TFFTEM # 1/Z E:(11) M:(10)
059963,000582: 27,3267 41057 SL* BOVB
059964,000583: 27,3270 57576 0,2 # X2= -NA
059965,000584: 27,3271 45712 SIGNMPAC # IN CASE X= 1.0, CONTINUE
059966,000585: 27,3272 00043 STORE TFFX # X=1/ALFA ZSQ
059967,000586: 27,3273 41234 RTB DMP
059968,000587: 27,3274 57334 T(X) # POLY
059969,000588: 27,3275 00043 TFFX
059970,000589: 27,3276 45242 SR3 DSU
059971,000590: 27,3277 17364 DP2(-3)
059972,000591: 27,3300 41405 DMP PUSH # 2(X T(X)-1) /Z ALFA E:(-15-NA)
059973,000592: # M:(-14-NA)
059974,000593: # 1/ALFA Z FROM PDL+0 E:(-11-NA)
059975,000594: # M:(-10-NA)
059976,000595: 27,3301 41345 DLOAD DMP # GET SIGN FOR SDELF
059977,000596: 27,3302 00045 TFFTEM # 1/Z E:(11) M:(10)
059978,000597: 27,3303 00015 RMAG1 # E:(-29) M:(-27)
059979,000598: 27,3304 43312 SL2 DAD
059980,000599: 27,3305 00017 TFFQ1 # Q1 E:(-16) M:(-15)
059981,000600: 27,3306 14045 STODL TFFTEM # (Q1+R 1/Z) =SGN OF SDELF E:(-16) M:(-15)
059982,000601: 27,3307 00035 TFFNP # LC P E:(-38+2NR) M:(-36+2NR)
059983,000602: 27,3310 53605 DMP SL* # CALC FOR ARG FOR TFF/TRIG.
059984,000603: # Page 1386
059985,000604: 27,3311 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
059986,000605: 27,3312 57575 1,2 # X2=-NA
059987,000606: 27,3313 53765 SIGN SL*
059988,000607: 27,3314 00045 TFFTEM # AFFIX SIGN FOR SDELF
059989,000608: 27,3315 57576 0,2
059990,000609: 27,3316 14045 STODL TFFTEM # P/ALFA E:(-59+2NR) M:(-55+2NR)
059991,000610: # (ARG FOR USE IN TFF/TRIG)
059992,000611: 27,3317 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
059993,000612: 27,3320 41366 SQRT DMP
059994,000613: 27,3321 17356 PI/16 # PI (-4)
059995,000614: 27,3322 77615 DAD
059996,000615: # 2(XT(X)-1)/Z ALFA FROM PDL E:(-15-NA)
059997,000616: # M:(-14-NA)
059998,000617: 27,3323 45257 SL* DSU
059999,000618: 27,3324 57577 0 -1,2
060000,000619: 27,3325 00013 TFFDELQ # Q2-Q1 E:(-16) M:(-15)
060001,000620: 27,3326 53605 DMP SL*
060002,000621: 27,3327 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
060003,000622: 27,3330 57601 0 -3,2
060004,000623: 27,3331 52057 SL* GOTO
060005,000624: 27,3332 57602 0 -4,2
060006,000625: 27,3333 57240 ENDTFF # TFF SQRT(MU) IN MPAC E:(-145) M:(-42)
060007,000626:
060008,000627: # Page 1387
060009,000628: # PROGRAM NAME: T(X) DATE: 01.17.67
060010,000629: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
060011,000630: # MOD BY: RR BAIRNSFATHER
060012,000631:
060013,000632: # FUNCTIONAL DESCRIPTION: THE POLYNOMIAL T(X) IS USED BY TIME OF FLIGHT SUBROUTINES CALCTFF AND
060014,000633: # CALCTPER TO APPROXIMATE THE SERIES
060015,000634: # 2 3
060016,000635: # 1/3 -X/5 +X /7 -X /9 ...
060017,000636:
060018,000637: # WHERE X = ALFA Z Z IF ALFA Z Z LEQ 1
060019,000638: # X = 1/(ALFA Z Z) IF ALFA Z Z G 1
060020,000639:
060021,000640: # ALSO X IS NEG FOR HYPERBOLIC ORBITS
060022,000641: # X = 0 FOR PARABOLIC ORBITS
060023,000642: # X IS POSITIVE FOR ELLIPTIC ORBITS
060024,000643:
060025,000644: # FOR FLIGHT 278, THE POLYNOMIAL T(X) IS FITTED OVER THE RANGE (0,+1) AND HAS A MAXIMUM
060026,000645: # DEVIATION FROM THE SERIES OF 2 E-5. (T(X) IS A CHEBYCHEV TYPE FIT AND WAS OBTAINED USING
060027,000646: # MAC PROGRAM AUTCURFIT294RRB AND IS VALID TO THE SAME TOLERANCE OVER THE RANGE (-.08,+1).)
060028,000647:
060029,000648: # CALLING SEQUENCE: RTB
060030,000649: # T(X)
060031,000650: # C(MPAC) = X
060032,000651:
060033,000652: # SUBROUTINE CALLED: NONE
060034,000653:
060035,000654: # NORMAL EXIT MODE: TC DANZIG
060036,000655:
060037,000656: # ALARMS: NONE
060038,000657:
060039,000658: # OUTPUT: C(MPAC) = T(X)
060040,000659:
060041,000660: # ERASABLE INITIALIZATION REQUIRED:
060042,000661: # C(MPAC) = X
060043,000662:
060044,000663: # DEBRIS: NONE
060045,000664:
060046,000665: 27,3334 07171 T(X) TC POLY
060047,000666: 27,3335 00004 DEC 4 B-14 # N-1
060048,000667: 27,3336 12525 12525 2DEC 3.333333333 E-1
060049,000668: 27,3340 71463 57703 2DEC* -1.999819135 E-1*
060050,000669: 27,3342 04423 17645 2DEC* 1.418148467 E-1*
060051,000670: 27,3344 74604 43667 2DEC* -1.01310997 E-1*
060052,000671: 27,3346 01626 37256 2DEC* 5.609004986 E-2*
060053,000672: 27,3350 77404 52071 2DEC* -1.536156925 E-2*
060054,000673:
060055,000674: 27,3352 06030 ENDT(X) TC DANZIG
060056,000675:
060057,000676: 27,3353 27,3352 TCDANZIG = ENDT(X)
060058,000677:
060059,000678: # Page 1388
060060,000679: # TFF CONSTANTS
060061,000680:
060062,000681: 32,3770 BANK 32
060063,000682:
060064,000683: 27,2000 SETLOC TOF-FF1
060065,000684: 27,2000 BANK
060066,000685:
060067,000686: # # NOTE _ NOTE _ ADJUSTED MUE FOR NEAR EARTH TRAJ.
060068,000687: # MUE = 3.990815471 E10 # M CUBE/CS SQ
060069,000688: # RTMUE = 1.997702549 E5 B-18* # MODIFIED EARTH MU
060070,000689:
060071,000690: 27,3353 24775 30424 1/RTMU 2DEC* .5005750271 E-5 B17* # MODIFIED EARTH MU
060072,000691:
060073,000692: # # NOTE _ NOTE _ ADJUSTED MUE FOR NEAR EARTH TRAJ.
060074,000693: # MUM = 4.902778 E8 # M CUBE/CS SQ
060075,000694: # RTMUM 2DEC* 2.21422176 E4 B-18*
060076,000695: 27,3355 06220 37553 PI/16 2DEC 3.141592653 B-4
060077,000696: 27,3357 37777 37700 LIM(-22) 2OCT 3777737700 # 1.0 -B(-22)
060078,000697: 27,3361 00000 00100 DP(-22) 2OCT 0000000100 # B(-22)
060079,000698: 27,3363 04000 00000 DP2(-3) 2DEC 1 B-3
060080,000699: 27,3365 02000 00000 DP2(-4) 2DEC 1 B-4 # 1/16
060081,000700:
060082,000701: # RPAD1 2DEC 6373338 B-29 # M (-29) = 20909901.57 FT
060083,000702: 27,3367 22,3151 RPAD1 = RPAD
060084,000703:
060085,000704: 27,3367 00305 11205 R300K 2DEC 6464778 B-29 # (-29) M
060086,000705: 27,3371 37777 37777 NEARONE 2DEC .999999999
060087,000706: 27,3373 26,3334 TFFZEROS EQUALS HI6ZEROS
060088,000707: 27,3373 26,3324 TFF1/4 EQUALS HIDP1/4
060089,000708:
060090,000709:
060091,000710:
End of include-file TIME_OF_FREE_FALL.agc. Parent file is MAIN.agc