Source Code
052356,000001: # Copyright: Public domain.
052357,000002: # Filename: TIME_OF_FREE_FALL.agc
052358,000003: # Purpose: A section of Luminary 1C, revision 131.
052359,000004: # It is part of the source code for the Lunar Module's (LM)
052360,000005: # Apollo Guidance Computer (AGC) for Apollo 13 and Apollo 14.
052361,000006: # This file is intended to be a faithful transcription, except
052362,000007: # that the code format has been changed to conform to the
052363,000008: # requirements of the yaYUL assembler rather than the
052364,000009: # original YUL assembler.
052365,000010: # Reference: pp. 1265-1280 of 1729.pdf.
052366,000011: # Contact: Ron Burkey <info@sandroid.org>.
052367,000012: # Website: www.ibiblio.org/apollo/index.html
052368,000013: # Mod history: 06/03/03 RSB. Began transcribing.
052369,000014: # 05/14/05 RSB Corrected website reference above
052370,000015: # 2010-10-25 JL Indentation fixes.
052371,000016:
052372,000017: # Page 1265
052373,000018: # THE TFF SUBROUTINES MAY BE USED IN EITHER EARTH OR MOON CENTERED COORDINATES. THE TFF ROUTINES NEVER
052374,000019: # KNOW WHICH ORIGIN APPLIES. IT IS THE USER WHO KNOWS, AND WHO SUPPLIES RONE, VONE, AND 1/SQRT(MU) AT THE
052375,000020: # APPROPIRATE SCALE LEVEL FOR THE PROPER PRIMARY BODY.
052376,000021:
052377,000022: # EARTH ORIGIN POSITION -29 METERS
052378,000023: # VELOCITY -7 METERS/CENTISECOND
052379,000024: # 1/SQRT(MU) +17 SQRT(CS SQ/METERS CUBED)
052380,000025:
052381,000026: # MOON ORIGIN POSITION -27 METERS
052382,000027: # VELOCITY -5 METERS/CENTISECONDS
052383,000028: # 1/SQRT(MU) +14 SQRT(CS SQ/METERS CUBED)
052384,000029:
052385,000030: # ALL DATA PROVIDED TO AND RECEIVED FROM ANY TFF SUBROUTINE WILL BE AT ONE OF THE LEVELS ABOVE. IN ALL CASES,
052386,000031: # THE FREE FALL TIME IS RETURNED IN CENTISECONDS AT (-28). PROGRAM TFF/CONIC WILL GENERATE VONE/RTMU AND
052387,000032: # LEAVE IT IN VONE' AT (+10) IF EARTH ORIGIN AND (+9) IF MOON ORIGIN.
052388,000033:
052389,000034: # THE USER MUST STORE THE STATE VECTOR IN RONE, VONE, AND MU IN THE FORM 1/SQRT(MU) IN TFF/RTMU
052390,000035: # AT THE PROPER SCALE BEFORE CALLING TFF/CONIC. SINCE RONE, VONE ARE IN THE EXTENDED VERB STORAGE AREA,
052391,000036: # THE USER MUST ALSO LOCK OUT THE EXTENDED VERBS, AND RELEASE THEM WHEN FINISHED.
052392,000037:
052393,000038: # PROGRAMS CALC/TFF AND CALC/TPER ASSUME THAT THE TERMINAL RADIUS IS LESS THAN THE PRESENT
052394,000039: # RADIUS. THIS RESTRICTION CAN BE REMOVED BY A 15 W CODING CHANGE, BUT AT PRESENT IT IS NOT DEEMED NECESSARY.
052395,000040:
052396,000041: # THE FOLLOWING ERASABLE QUANTITIES ARE USED BY THE TFF ROUTINES, AND ARE LOCATED IN THE PUSH LIST.
052397,000042:
052398,000043: # BELOW E: IS USED FOR EARTH ORIGIN SCALE
052399,000044: # M: IS USED FOR MOON ORIGIN SCALE
052400,000045:
052401,000046: # TFFSW = 119D # BIT1 0 = CALCTFF 1 = CALCTPER
052402,000047: 10,2213 TFFDELQ = 10D # Q2-Q1 E: (-16) M: (-15)
052403,000048: 10,2213 RMAG1 = 12D # ABVAL(RN) M E: (-29) M: (-27)
052404,000049: # RPER = 14D # PERIGEE RADIUS M E: (-29) M: (-27)
052405,000050: 10,2213 TFFQ1 = 14D # R.V / SQRT(MUE) E: (-16) M: (-15)
052406,000051: # SDELF/2 # SIN(THETA) /2
052407,000052: 10,2213 CDELF/2 = 14D # COS(THETA) /2
052408,000053: # RAPO = 16D # APOGEE RADIUS M E: (-29) M: (-27)
052409,000054: 10,2213 NRTERM = 16D # TERMINAL RADIUS M E: (-29+NR)
052410,000055: # M: (-27+NR)
052411,000056: 10,2213 RTERM = 18D # TERMINAL RADIUS M E: (-29) M: (-27)
052412,000057: 10,2213 TFFVSQ = 20D # -(V SQUARED/MU) 1/M E: (20) M: (18)
052413,000058: 10,2213 TFF1/ALF = 22D # SEMI MAJ AXIS M E: (-22-2 NA)
052414,000059: # M: (-20-2 NA)
052415,000060: 10,2213 TFFRTALF = 24D # SQRT(ALFA) E:(10+NA) M: (9+NA)
052416,000061: 10,2213 TFFALFA = 26D # ALFA 1/M E:(26-NR) M: (24-NR)
052417,000062: 10,2213 TFFNP = 28D # SEMI LATUS RECTUM M E: (-38+2 NR)
052418,000063: # M: (-36+2 NR)
052419,000064: 10,2213 TFF/RTMU = 30D # 1/SQRT(MU) E: (17) M: (14)
052420,000065: 10,2213 NRMAG = 32D # PRESENT RADIUS M E: (-29+NR)
052421,000066: # M: (-27+NR)
052422,000067: 10,2213 TFFX = 34D
052423,000068: 10,2213 TFFTEM = 36D # TEMPORARY
052424,000069: # Page 1266
052425,000070: # REGISTERS S1, S2 ARE UNTOUCED BY ANY TFF SUBROUTINE
052426,000071: # INDEX REGISTERS X1, X2 ARE USED BY ALL TFF SUBROUTINES. THEY ARE ESTAB-
052427,000072: # LISHED IN TFF/CONIC AND MUST BE PRESERVED BETWEEN CALLS TO SUBSEQUENT
052428,000073: # SUBROUTINES.
052429,000074: # -NR C(X1) = NORM COUNT OF RMAG
052430,000075: # -NA C(X2) = NORM COUNT OF SQRT(ABS(ALFA))
052431,000076:
052432,000077: # Page 1267
052433,000078: # SUBROUTINE NAME: TFFCONIC DATE: 01.29.67
052434,000079: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
052435,000080: # MOD BY: RR BAIRNSFATHER
052436,000081: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 11 APR 67
052437,000082: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 21 NOV 67 ADD MOON MU.
052438,000083: # MOD NO: 3 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
052439,000084:
052440,000085: # FUNCTIONAL DESCRIPTION: THIS SUBROUTINE IS CALLED TO COMPUTE THOSE CONIC PARAMETERS REQUIRED BY THE TFF
052441,000086: # SUBROUTINES AND TO ESTABLISH THEM IN THE PUSH LIST AREA. THE PARAMETERS ARE LISTED UNDER OUTPUT.
052442,000087: # THE EQUATIONS ARE:
052443,000088: # _ __ __
052444,000089: # H = RN*VN ANGULAR MOMENTUM
052445,000090: # _ _
052446,000091: # LCP = H.H / MU SEMI LATUS RECTUM
052447,000092: # __ __
052448,000093: # ALFA = 2/RN - VN.VN / MU RECIPROCAL SEMI-MAJOR AXIS, SIGNED
052449,000094:
052450,000095: # AND ALFA IS POS FOR ELLIPTIC ORBITS
052451,000096: # 0 FOR PARABOLIC ORBITS
052452,000097: # NEG FOR HYPERBOLIC ORBITS
052453,000098: # SUBROUTINE ALSO COMPUTES AND SAVES RMAG.
052454,000099:
052455,000100: # CALLING SEQUENCE:
052456,000101: # TFFCONIC EXPECTS CALLER TO ENTER WITH CORRECT GRAVITATIONAL CONSTANT IN MPAC, IN THE FORM
052457,000102: # 1/SQRT(MU). THE PROGRAM WILL SAVE IN TFF/RTMU. THE SCALE IS DETERMINED BY WHETHER EARTH OR MOON
052458,000103: # ORIGIN IS USED. THE CALLER MUST LOCK OUT THE EXTENDED VERBS BEFORE PROVIDING STATE VECTOR IN RONE,
052459,000104: # VONE AT PROPER SCALE. THE EXTENDED VERBS MUST BE RESTORED WHEN THE CALLER IS FINISHED USING THE
052460,000105: # TFF ROUTINES.
052461,000106:
052462,000107: # ENTRY POINT TFFCONMU EXPECTS THAT TFF/RTMU IS ALREADY LOADED.
052463,000108:
052464,000109: # TO SPECIFY MU: DLOAD CALL # IF MU ALREADY STORED: CALL
052465,000110: # YOURMU # 1/RTMU E:(17) M:(14) TFFCONMU
052466,000111: # TFFCONIC
052467,000112: # PUSHLOC = PDL+0, ARBITRARY IF LEQ 18D
052468,000113:
052469,000114: # SUBROUTINES CALLED: NONE
052470,000115:
052471,000116: # NORMAL EXIT MODES: RVQ
052472,000117:
052473,000118: # ALARMS: NONE
052474,000119:
052475,000120: # OUTPUT: THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
052476,000121: # RMAG1 E:(-29) M:(-27) M RN, PRESENT RADIUS LENGTH.
052477,000122: # NRMAG E:(-29+NR) M RMAG, NORMALIZED
052478,000123: # M:(-27+NR)
052479,000124: # X1 -NR, NORM COUNT
052480,000125: # TFFNP E:(-38+2NR) M LCP, SEMI LATUS RECTUM, WEIGHTED BY NR. FOR VGAMCALC.
052481,000126: # M:(-36+2NR)
052482,000127: # TFF/RTMU E:(17) M:(14) 1/SQRT(MU)
052483,000128: # TFFVSQ E:(20) M:(18) 1/M -(V SQ/MU): PRESENT VELOCITY, NORMALIZED. FOR VGAMCALC
052484,000129: # TFFALFA E:(26-NR) 1/M ALFA, WEIGHTED BY NR
052485,000130: # M:(24-NR)
052486,000131: # TFFRTALF E:(10+NA) SQRT(ALFA), NORMALIZED
052487,000132: # M:(9+NA)
052488,000133: # Page 1268
052489,000134: # X2 -NA, NORMCOUNT
052490,000135: # TFF1/ALF E:(-22-2NA) SIGNED SEMI-MAJOR AXIS, WEIGHTED BY NA
052491,000136: # M:(-20-2NA)
052492,000137: # PUSHLOC AT PDL+0
052493,000138:
052494,000139: # THE FOLLOWING IS STORED IN GENERAL ERASABLE
052495,000140: # VONE' E:(10) M:(9) V/RT(MU), NORMALIZED VELOCITY
052496,000141:
052497,000142: # ERASABLE INITIALIZATION REQUIRED:
052498,000143: # RONE E:(-29) M:(-27) M STATE VECTOR LEFT BY CALLER
052499,000144: # VONE E:(-7) M:(-5) M/CS STATE VECTOR LEFT BY CALLER
052500,000145: # TFF/RTMU E:(17) M:(14) 1/RT(CS SQ/M CUBE) IF ENTER VIA TFFCONMU.
052501,000146:
052502,000147: # DEBRIS: QPRET PDL+0 ... PDL+3
052503,000148:
052504,000149: 33,3760 BANK 33
052505,000150: 27,2000 SETLOC TOF-FF
052506,000151: 27,2000 BANK
052507,000152:
052508,000153: 27,3361 COUNT* $$/TFF
052509,000154:
052510,000155: 27,3361 00037 TFFCONIC STORE TFF/RTMU # 1/SQRT(MU) E:(17) M:(14)
052511,000156:
052512,000157: 27,3362 53575 TFFCONMU VLOAD UNIT # COME HERE WITH TFFRTMU LOADED.
052513,000158: 27,3363 02207 RONE # SAVED RN. M E:(-29) M:(-27)
052514,000159: 27,3364 77725 PDDL # UR/2 TO PDL+0, +5
052515,000160: 27,3365 00045 36D # MAGNITUDE
052516,000161: 27,3366 00015 STORE RMAG1 # M E:(-29) M:(-27)
052517,000162:
052518,000163: 27,3367 77701 NORM
052519,000164: 27,3370 00047 X1 # -NR
052520,000165: 27,3371 24041 STOVL NRMAG # RMAG M E:(-29+NR) M:(-27+NR)
052521,000166: 27,3372 02215 VONE # SAVED VN. M/CS E:(-7) M:(-5)
052522,000167: 27,3373 77761 VXSC
052523,000168: 27,3374 00037 TFF/RTMU # E:(17) M:(14)
052524,000169: 27,3375 02170 STORE VONE' # VN/SQRT(MU) E:(10) M:(9)
052525,000170:
052526,000171: 27,3376 47361 VXSC VXV
052527,000172: 27,3377 00041 NRMAG # E:(-29+NR) M:(-27+NR)
052528,000173: # UR/2 FROM PDL
052529,000174: 27,3400 47572 VSL1 VSQ # BEFORE: E:(-19+NR) M:(-18+NR)
052530,000175: 27,3401 14035 STODL TFFNP # LC P M E:(-38+2NR) M:(-36+2NR)
052531,000176: # SAVE ALSO FOR VGAMCALC
052532,000177: 27,3402 06514 TFF1/4
052533,000178: 27,3403 63271 DDV PDVL # (2/RMAG) 1/M E:(26-NR) M:(24-NR)
052534,000179: 27,3404 00041 NRMAG # RMAG M E:(-29+NR) M:(-27+NR)
052535,000180: 27,3405 02170 VONE' # SAVED VN. E:(10) M:(9)
052536,000181: 27,3406 57436 VSQ DCOMP # KEEP MPAC+2 HONEST FOR SQRT.
052537,000182: 27,3407 00025 STORE TFFVSQ # -(V SQ/MU) E:(20) M:(18)
052538,000183: # SAVE FOR VGAMCALC
052539,000184: 27,3410 43257 SR* DAD
052540,000185: # Page 1269
052541,000186: 27,3411 20573 0 -6,1 # GET -VSQ/MU E:(26-NR) M:(24-NR)
052542,000187: 27,3412 77626 STADR
052543,000188: # 2/RMAG FROM PDL+2
052544,000189: 27,3413 77744 STORE TFFALFA # ALFA 1/M E:(26-NR) M:(24-NR)
052545,000190: 27,3414 41457 SL* PUSH # TEMP SAVE ALFA E:(20) M:(18)
052546,000191: 27,3415 20173 0 -6,1
052547,000192: 27,3416 75446 ABS SQRT # E:(10) M:(9)
052548,000193: 27,3417 77701 NORM
052549,000194: 27,3420 00050 X2 # X2 = -NA
052550,000195: 27,3421 00031 STORE TFFRTALF # SQRT( ABS(ALFA) ) E:(10+NA) M:(9+NA)
052551,000196: 27,3422 75316 DSQ SIGN # NOT SO ACCURATE, BUT OK
052552,000197: # ALFA FROM PDL+2 E:(20) M:(18)
052553,000198: 27,3423 55254 BZE BDDV # SET 1/ALFA =0, TO SHOW SMALL ALFA
052554,000199: 27,3424 57426 +2
052555,000200: 27,3425 06514 TFF1/4
052556,000201: 27,3426 00027 +2 STORE TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
052557,000202: 27,3427 77616 DUMPCNIC RVQ
052558,000203:
052559,000204: # Page 1270
052560,000205: # SUBROUTINE NAME: TFFRP/RA DATE: 01.17.67
052561,000206: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
052562,000207: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 11 APR 67
052563,000208: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
052564,000209: # ALSO IMPROVE ACCURACY OF RAPO.
052565,000210:
052566,000211: # FUNCTIONAL DESCRIPTION: USED BY CALCTPER AND TFF DISPLAYS TO CALCULATE PERIGEE RADIUS AND ALSO
052567,000212: # APOGEE RADIUS FOR A GENERAL CONIC.
052568,000213: # PROGRAM GIVES PERIGEE RADIUS AS APOGEE RADIUS IS GIVEN BY
052569,000214: # RP = P/(1+E) RA = (1+E) / ALFA
052570,000215: # WHERE 2
052571,000216: # E = 1 - P ALFA
052572,000217: # IF RA IS NEGATIVE OR SHOWS DIVIDE OVERFLOW, THEN RA = POSMAX BECAUSE
052573,000218: # 1. APOGEE RADIUS IS NOT MEANINGFUL FOR HYPERBOLA
052574,000219: # 2. APOGEE RADIUS IS NOT DEFINED FOR PARABOLA
052575,000220: # 3. APOGEE RADIUS EXCEEDS THE SCALING FOR ELLIPSE.
052576,000221:
052577,000222: # THIS SUBROUTINE REQUIRED THE SIGNED RECIPROCAL SEMI-MAJOR AXIS, ALFA, AND SEMI-LATUS RECTUM AS DATA.
052578,000223:
052579,000224: # CALLING SEQUENCE: CALL
052580,000225: # TFFRP/RA
052581,000226: # PUSHLOC = PDL+0, ARBITRARY IF LEQ 10D
052582,000227: # C(MPAC) UNSPECIFIED
052583,000228:
052584,000229: # SUBROUTINES CALLED: NONE
052585,000230:
052586,000231: # NORMAL EXIT MODE: RVQ
052587,000232: # IF ELLIPSE, WITHIN NORMAL SCALING, RAPO IS CORRECT.
052588,000233: # OTHERWISE, RAPO = POSMAX.
052589,000234:
052590,000235: # ALARMS: NONE
052591,000236:
052592,000237: # OUTPUT: STORED IN PUSH LIST AREA. SCALE OF OUTPUT AGREES WITH DATA SUPPLIED TO TFF/CONIC.
052593,000238: # RPER E:(-29) M:(-27) M PERIGEE RADIUS DESTROYED BY CALCTFF/CALCTPER, TFFTRIG.
052594,000239: # RAPO E:(-29) M:(-27) M APOGEE RADIUS WILL BE DESTROYED BY CALCTFF/CALCTPER
052595,000240: # PUSHLOC AT PDL+0
052596,000241:
052597,000242: # ERASABLE INITIALIZATION REQUIRED:
052598,000243: # TFFALFA E:(26-NR) M 1/SEMI-MAJOR AXIS LEFT BY TFFCONIC
052599,000244: # M:(24-NR)
052600,000245: # TFFNP E:(-38+2NR) M LC P, SEMI LATUS RECTUM LEFT BY TFFCONIC
052601,000246: # M:(-36+2NR)
052602,000247: # X1 -NR, NORM COUNT OF RMAG LEFT BY TFFCONIC
052603,000248: # X2 -NA, NORM COUNT OF ALFA LEFT BY TFFCONIC
052604,000249:
052605,000250: # DEBRIS: QPRET, PDL+0 ... PDL+1
052606,000251:
052607,000252: # Page 1271
052608,000253: 27,3430 RAPO = 16D # APOGEE RADIUS M E:(-29) M:(-27)
052609,000254: 27,3430 RPER = 14D # PERIGEE RADIUS M E:(-29) M:(-27)
052610,000255:
052611,000256: 27,3430 41345 TFFRP/RA DLOAD DMP
052612,000257: 27,3431 00033 TFFALFA # ALFA 1/M E:(26-NR) M:(24-NR)
052613,000258: 27,3432 00035 TFFNP # LC P M E:(-38+2NR) M:(-36+2NR)
052614,000259: 27,3433 57457 SR* DCOMP # ALFA P (-12+NR)
052615,000260: 27,3434 20571 0 -8D,1 # ALFA P (-4)
052616,000261: 27,3435 51415 DAD ABS # (DCOMP GIVES VALID TP RESULT FOR SQRT)
052617,000262: # (ABS PROTECTS SQRT IF E IS VERY NEAR 0)
052618,000263: 27,3436 17766 DP2(-4)
052619,000264: 27,3437 43366 SQRT DAD # E SQ = (1- P ALFA) (-4)
052620,000265: 27,3440 06514 TFF1/4
052621,000266: 27,3441 55206 PUSH BDDV # (1+E) (-2) TO PDL+0
052622,000267: 27,3442 00035 TFFNP # LCP M E:(-38+2NR) M:(-36+2NR)
052623,000268: 27,3443 53657 SR* SR* # (DOES SR THEN SL TO AVOID OVFL)
052624,000269: 27,3444 20601 0,1 # X1=-NR
052625,000270: 27,3445 20572 0 -7,1 # (EFFECTIVE SL)
052626,000271: 27,3446 14017 STODL RPER # PERIGEE RADIUS M E:(-29) M:(-27)
052627,000272: # (1+E) (-2) FROM PDL+0
052628,000273: 27,3447 41005 DMP BOVB
052629,000274: 27,3450 00027 TFF1/ALF # E:(-22-2NA) M:(-20-2NA)
052630,000275: 27,3451 57754 TCDANZIG # CLEAR OVFIND, IF ON.
052631,000276: 27,3452 53654 BZE SL*
052632,000277: 27,3453 57462 MAXRA # SET POSMAX IF ALFA=0
052633,000278: 27,3454 57603 0 -5,2 # -5+NA
052634,000279: 27,3455 40057 SL* BOV
052635,000280: 27,3456 57576 0,2
052636,000281: 27,3457 57462 MAXRA # SET POSMAX IF OVFL.
052637,000282: 27,3460 77644 BPL # CONTINUE WITH VALID RAPO.
052638,000283: 27,3461 57464 +3
052639,000284: 27,3462 77745 MAXRA DLOAD # RAPO CALC IS NOT VALID. SET RAPO =
052640,000285: 27,3463 17772 NEARONE # POSMAX AS A TAG.
052641,000286: 27,3464 00021 +3 STORE RAPO # APOGEE RADIUS M E:(-29) M:(-27)
052642,000287: 27,3465 77616 DUMPRPRA RVQ
052643,000288:
052644,000289: # Page 1272
052645,000290: # SUBROUTINE NAME: CALCTPER / CALCTFF DATE: 01.29.67
052646,000291: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
052647,000292: # MOD BY: RR BAIRNSFATHER
052648,000293: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 67
052649,000294: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 14 APR 67
052650,000295: # MOD BY: 3 MOD BY: RR BAIRNSFATHER DATE: 8 JUL 67 NEAR EARTH MUE AND NEG TFF (GONEPAST)
052651,000296: # MOD BY: 4 MOD BY: RR BAIRNSFATHER DATE: 21 NOV 67 ADD VARIABLE MU.
052652,000297: # MOD BY: 5 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
052653,000298:
052654,000299: # FUNCTIONAL DESCRIPTION: PROGRAM CALCULATES THE FREE-FALL TIME OF FLIGHT FROM PRESENT POSITION RN AND
052655,000300: # VELOCITY VN TO A RADIUS LENGTH SPECIFIED BY RTERM, SUPPLIED BY THE USER. THE POSITION VECTOR
052656,000301: # RN MAY BE ON EITHER SIDE OF THE CONIC, BUT RTERM IS CONSIDERED ON THE INBOUND SIDE.
052657,000302: # THE EQUATIONS ARE:
052658,000303:
052659,000304: # Q2 = -SQRT(RTERM (2-RTERM ALFA) - LCP) (INBOUND SIDE) LEQ +- LCE/SQRT(ALFA)
052660,000305: # __ __
052661,000306: # Q1 = RN.VN / SQRT(MU) LEQ +- LCE/SQRT(ALFA)
052662,000307:
052663,000308: # Z = NUM / DEN LEQ +- 1/SQRT(ALFA)
052664,000309:
052665,000310: # WHERE, IF INBOUND
052666,000311: # NUM = RTERM -RN LEQ +- 2 LCE/ALFA
052667,000312: # DEN = Q2+Q1 LEQ +- 2 LCE/SQRT(ALFA)
052668,000313:
052669,000314: # AND, IF OUTBOUND
052670,000315: # NUM = Q2-Q1 LEQ +- 2 LCE/SQRT(ALFA)
052671,000316: # DEN = 2 - ALFA (RTERM + RN). LEQ +- 2 LCE
052672,000317:
052673,000318: # IF ALFA ZZ < 1.0 (FOR ALL CONICS EXCEPT ELLIPSES HAVING ABS(DEL ECC ANOM) G 90 DEG)
052674,000319: # THEN X = ALFA Z Z
052675,000320: # AND TFF = (RTERM +RN -2 ZZ T(X) ) Z/SQRT(MU)
052676,000321: # EXCEPT IF ALFA PNZ, AND IF TFF NEG,
052677,000322: # THEN TFF = 2 PI /(ALFA SQRT(ALFA)) + TFF
052678,000323: # OR IF ALFA ZZ GEQ 1.0 (FOR ELLIPSES HAVING ABS(DEL ECC ANOM) GEQ 90 DEG)
052679,000324: # THEN X = 1/ALFA Z Z
052680,000325: # AND TFF = (PI/SQRT(ALFA) -Q2 +Q1 +2(X T(X) -1) /ALFA Z) /ALFA SQRT(MU)
052681,000326: # WHERE T(X) IS A POLYNOMIAL APPROXIMATION TO THE SERIES
052682,000327: # 2 3 2
052683,000328: # 1/3 - X/5 + X /7 - X /8 ... (X < 1.0)
052684,000329:
052685,000330: # CALLING SEQUENC: TIME TO RTERM TIME TO PERIGEE
052686,000331: # CALL CALL
052687,000332: # CALCTFF CALCTPER
052688,000333: # C(MPAC) = TERMNL RAD M C(MPAC) = PERIGEE RAD M
052689,000334: # FOR EITHER, E:(-29) M:(-27)
052690,000335: # FOR EITHER, PUSHLOC = PDL+0, ARBITRARY IF LEQ 8D.
052691,000336: # Page 1273
052692,000337:
052693,000338: # SUBROUTINES CALLED: T(X), VIA RTB
052694,000339:
052695,000340: # NORMAL EXIT MODE: RVQ
052696,000341: # HOWEVER, PROGRAM EXITS WITH ONE OF THE FOLLOWING VALUES FOR TFF (-28) CS IN MPAC. USER MUST STORE.
052697,000342: # A. TFF = FLIGHT TIME. NORMAL CASE FOR POSITIVE FLIGHT TIME LESS THAN ONE ORBITAL PERIOD.
052698,000343: # B. (THIS OPTION IS NO LONGER USED.)
052699,000344: # C. TFF = POSMAX. THIS INDICATES THAT THE CONIC FROM THE PRESENT POSITION WILL NOT RETURN TO
052700,000345: # THE SPECIFIED ALTITUDE. ALSO INDICATES OUTBOUND PARABOLA OR HYPERBOLA.
052701,000346:
052702,000347: # OUTPUT: C(MPAC) (-28) CS TIME OF FLIGHT, OR TIME TO PERIGEE
052703,000348: # TFFX (0) X LEFT FOR ENTRY DISPLAY TFF ROUTINES
052704,000349: # NRTERM E:(-29+NR) M RTERM, WEIGHTED BY NR LEFT FOR ENTRY DISPLAY TFF ROUTINES
052705,000350: # M:(-27+NR)
052706,000351: # TFFTEM E:(-59+2NR) LCP Z Z SGN(SDELF) LEFT FOR ENTRY DISPLAY TFF ROUTINES
052707,000352: # M:(-55+2NR) LCP /ALFA SGN(SDELF) LEFT FOR ENTRY DISPLAY TFF ROUTINES
052708,000353: # NOTE: TFFTEM = PDL 36D AND WILL BE DESTROYED BY .:UNIT:.
052709,000354: # RMAG1 E:(-29) M:(-27) PDL 12 NOT TOUCHED.
052710,000355: # TFFQ1 E:(-16) M:(-15) PDL 14D
052711,000356: # TFFDELQ E:(-16) M:(-15) PDL 10D
052712,000357: # PUSHLOC AT PDL+0
052713,000358:
052714,000359: # ERASABLE INITIALIZATION REQUIRED:
052715,000360: # RONE E:(-29) M:(-27) M STATE VECTOR LEFT BY USER
052716,000361: # VONE' E:(+10) M:(+9) VN/SQRT(NU) LEFT BY TFF/CONIC
052717,000362: # RMAG1 E:(-29) M:(-27) PRESENT RADIUS, M LEFT BY TFFCONIC
052718,000363: # C(MPAC) E:(-29) M:(-27) RTERM, TERMINAL RADIUS LENGTH, M LEFT BY USER
052719,000364:
052720,000365: # THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
052721,000366: # TFF/RTMU E:(17) M:(14) 1/SQRT(MU) LEFT BY TFFCONIC.
052722,000367: # NRMAG E:(-29+NR) M RMAG, NORMALIZED LEFT BY TFFCONIC
052723,000368: # M:(-27+NR)
052724,000369: # X1 -NR, NORM COUNT LEFT BY TFFCONIC
052725,000370: # TFFNP E:(-38+2NR) M LCP, SEMI LATUS RECTUM, WEIGHT NR LEFT BY TFFCONIC
052726,000371: # M:(-36+2N4)
052727,000372: # TFFALFA E:(26-NR) 1/M ALFA, WEIGHT NR LEFT BY TFFCONIC
052728,000373: # M:(24-NR)
052729,000374: # TFFRTALF E:(10+NA) SQRT(ALFA), NORMALIZED LEFT BY TFFCONIC
052730,000375: # M:(9+NA)
052731,000376: # X2 -NA, NORMCOUNT LEFT BY TFFCONIC
052732,000377: # TFF1/ALF E:(-22-2NA) SIGNED SEMI-MAJOR AXIS, WEIGHTED BY NA LEFT BY TFFCONIC
052733,000378: # M:(-20-2NA)
052734,000379:
052735,000380: # DEBRIS: QPRET, PDL+0 ... PDL+3
052736,000381: # RTERM E:(-29) M(-27) RTERM, TERMINAL RADIUS LENGTH
052737,000382: # RAPO E:(-29) M(-27) PDL 16D (=NRTERM)
052738,000383: # RPER E:(-29) M(-27) PDL 14D (=TFFQ1)
052739,000384:
052740,000385: # Page 1274
052741,000386: 27,3466 77614 CALCTPER SETGO # ENTER WITH RPER IN MPAC
052742,000387: 27,3467 03436 TFFSW
052743,000388: 27,3470 57473 +3
052744,000389: 27,3471 77614 CALCTFF CLEAR # ENTER WITH RTERM IN MPAC
052745,000390: 27,3472 03676 TFFSW
052746,000391: 27,3473 00023 +3 STORE RTERM # E:(-29) M:(-27)
052747,000392: 27,3474 77657 SL*
052748,000393: 27,3475 20201 0,1 # X1=-NR
052749,000394: 27,3476 00021 STORE NRTERM # RTERM E:(-29+NR) M:(-27+NR)
052750,000395: 27,3477 44205 DMP BDSU
052751,000396: 27,3500 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
052752,000397: 27,3501 06514 TFF1/4
052753,000398: 27,3502 41206 PUSH DMP # (2-ALFA RTERM) (-3) TO PDL+0
052754,000399: 27,3503 00021 NRTERM # E:(-29+NR) M:(-27+NR)
052755,000400: 27,3504 53725 PDDL SR* # RTERM(2-ALFA RTERM) TO PDL+2
052756,000401: # E:(-32+NR) M:(-30+NR)
052757,000402: 27,3505 00035 TFFNP # LC P E:(-38+2NR) M:(-36+2NR)
052758,000403: 27,3506 20573 0 -6,1 # X1 = -NR
052759,000404: 27,3507 43276 DCOMP DAD # DUE TO SHIFTS, KEEP PRECISION FOR SQRT
052760,000405: # RTERM(2-ALFA RTERM) FROM PDL +2
052761,000406: # E:(-32+NR) M:(-30+NR)
052762,000407: 27,3510 77657 SR* # LEAVE E:(-32) M:(-30)
052763,000408: 27,3511 20601 0,1 # X1 = -NR
052764,000409: 27,3512 71214 BOFF DLOAD # CHECK TFF /TPER SWITCH
052765,000410: 27,3513 03756 TFFSW
052766,000411: 27,3514 57516 +2 # IF TFF, CONTINUE
052767,000412: 27,3515 06524 TFFZEROS # IF TPER, SET Q2 = 0
052768,000413: 27,3516 75440 +2 BMN SQRT # E:(-16) M:(-15)
052769,000414: 27,3517 57651 MAXTFF1 # NO FREE FALL CONIC TO RTERM FROM HERE
052770,000415: # RESET PDL, SET TFF=POSMAX, AND EXIT.
052771,000416:
052772,000417: 27,3520 41076 DCOMP BOVB # RT IS ON INBOUND SIDE. ASSURE OVFIND=0
052773,000418: 27,3521 57754 TCDANZIG # ANY PORT IN A STORM.
052774,000419: 27,3522 24045 STOVL TFFTEM # Q2 E:(-16) M:(-15)
052775,000420: 27,3523 02170 VONE' # VN/SQRT(MU) E:(10) M:(9)
052776,000421: 27,3524 52441 DOT SL3
052777,000422: 27,3525 02207 RONE # SAVED RN. E:(-29) M:(-27)
052778,000423: 27,3526 00017 STORE TFFQ1 # Q1, SAVE FOR GONEPAST TEST.
052779,000424: # E:(-16) M:(-15)
052780,000425: 27,3527 44240 BMN BDSU
052781,000426: 27,3530 57551 INBOUND # USE ALTERNATE Z
052782,000427: 27,3531 00045 TFFTEM # Q2 E:(-16) M:(-15)
052783,000428:
052784,000429: # OUTBOUND Z CALC CONTINUES HERE
052785,000430:
052786,000431: 27,3532 14043 STODL TFFX # NUM=Q2-Q1 E:(-16) M:(-15)
052787,000432: 27,3533 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
052788,000433: 27,3534 44205 DMP BDSU
052789,000434: # Page 1275
052790,000435: 27,3535 00041 NRMAG # RMAG E:(-29+NR) M:(-27+NR)
052791,000436: # (2-RTERM ALFA) (-3) FROM PDL+0
052792,000437: 27,3536 51406 SAVEDEN PUSH ABS # DEN TO PDL+0 E:(-3) OR (-16)
052793,000438: # M:(-3) OR (-15)
052794,000439: 27,3537 40015 DAD BOV # INDETERMINANCY TEST
052795,000440: 27,3540 17760 LIM(-22) # =1.0-B(-22)
052796,000441: 27,3541 57562 TFFXTEST # GO IF DEN >/= B(-22)
052797,000442: 27,3542 65345 DLOAD PDDL # SET DEN=0 OTHERWISE
052798,000443: 27,3543 06524 TFFZEROS
052799,000444: # XCH ZERO WITH PDL+0
052800,000445: 27,3544 57545 DLOAD DCOMP
052801,000446: 27,3545 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
052802,000447: 27,3546 71240 BMN DLOAD # FOR TPER: Z INDET AT DELE/2=0 AND 90.
052803,000448: 27,3547 57656 TFFEL1 # ASSUME 90, AND LEAVE 0 IN PDL: 1/Z=D/N
052804,000449:
052805,000450: # Z INDET. AT PERIGEE FOR PARAB OR HYPERB.
052806,000451: 27,3550 77616 DUMPTFF1 RVQ # RETURN TFF =0
052807,000452:
052808,000453: # INBOUND Z CALC CONTINUES HERE
052809,000454:
052810,000455: 27,3551 77745 INBOUND DLOAD # RESET PDL+0
052811,000456: 27,3552 45345 DLOAD DSU # ALTERNATE Z CALC
052812,000457: 27,3553 00023 RTERM # E:(-29) M:(-27)
052813,000458: 27,3554 00015 RMAG1 # E:(-29) M:(-27)
052814,000459: 27,3555 14043 STODL TFFX # NUM=RTERM-RN E:(-29) M:(-27)
052815,000460: 27,3556 00045 TFFTEM # Q2 E:(-16) M:(-15)
052816,000461: 27,3557 52015 DAD GOTO
052817,000462: 27,3560 00017 TFFQ1 # Q1 E:(-16) M:(-15)
052818,000463: 27,3561 57536 SAVEDEN # DEN = Q2+Q1 E:(-16) M:(-15)
052819,000464:
052820,000465: 27,3562 65215 TFFXTEST DAD PDDL # (ABS(DEN) TO PDL+2) E:(-3) OR (-16)
052821,000466: # M:(-3) OR (-15)
052822,000467: 27,3563 17762 DP(-22) # RESTORE ABS(DEN) TO MPAC
052823,000468: 27,3564 00043 TFFX # NUM E:(-16) OR (-29) M:(-15) OR (-27)
052824,000469: 27,3565 53605 DMP SR*
052825,000470: 27,3566 00031 TFFRTALF # SQRT(ALFA) E:(10+NA) M:(9+NA)
052826,000471: 27,3567 57201 0 -3,2 # X2=-NA
052827,000472: 27,3570 77671 DDV # C(MPAC) =NUM SQRT(ALFA) E:(-3) OR (-16)
052828,000473: # M:(-3) OR (-15)
052829,000474: # ABS(DEN) FROM PDL+2 E:(-3) OR (-16)
052830,000475: # M:(-3) OR (-15)
052831,000476: 27,3571 40145 DLOAD BOV # (THE DLOAD IS SHARED WITH TFFELL)
052832,000477: 27,3572 00043 TFFX # NUM E:(-16) OR (-29) M:(-15) OR (-27)
052833,000478: 27,3573 57654 TFFELL # USE EQN FOR DELE GEQ 90, LEQ -90
052834,000479:
052835,000480: # OTHERWISE, CONTINUE FOR GENERAL CONIC FOR TFF EQN
052836,000481:
052837,000482: 27,3574 45471 DDV STADR
052838,000483: # DEN FROM PDL+0 E:(-3) OR (-16)
052839,000484: # M:(-3) OR (-15)
052840,000485: 27,3575 77732 STORE TFFTEM # Z SAVE FOR SIGN OF SDELF.
052841,000486: # Page 1276
052842,000487: # E:(-13) M:(-12)
052843,000488: 27,3576 63406 PUSH DSQ # Z TO PDL+0
052844,000489: 27,3577 41206 PUSH DMP # Z SQ TO PDL+2 E:(-26) M:(-24)
052845,000490: 27,3600 00035 TFFNP # LC P E:(-38+2NR) M:(-36+NR)
052846,000491: 27,3601 75261 SL SIGN
052847,000492: 27,3602 20206 5
052848,000493: 27,3603 00045 TFFTEM # AFFIX SIGN FOR SDELF (ENTRY DISPLAY)
052849,000494: 27,3604 14045 STODL TFFTEM # P ZSQ E:(-59+2NR) M:(-55+2NR)
052850,000495: # (ARG IS USED IN TFF/TRIG)
052851,000496: # ZSQ FROM PDL+2 E:(-26) M:(-24)
052852,000497: 27,3605 41206 PUSH DMP # RESTORE PUSH LOC
052853,000498: 27,3606 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
052854,000499: 27,3607 77657 SL*
052855,000500: 27,3610 20201 0,1 # X1=-NR
052856,000501: 27,3611 00043 STORE TFFX # X
052857,000502: 27,3612 41234 RTB DMP
052858,000503: 27,3613 57736 T(X) # POLY
052859,000504: # ZSQ FROM PDL+2 E:(-26) M:(-24)
052860,000505: 27,3614 44302 SR2 BDSU # 2 ZSQ T(X) E:(-29) M:(-27)
052861,000506: 27,3615 00023 RTERM # RTERM E:(-29) M:(-27)
052862,000507: 27,3616 41215 DAD DMP
052863,000508: 27,3617 00015 RMAG1 # E:(-29) M:(-27)
052864,000509: # Z FROM PDL+0 E:(-13) M:(-12)
052865,000510: 27,3620 51042 SR3 BPL # TFF SQRT(MU) E:(-45) M:(-42)
052866,000511: 27,3621 57642 ENDTFF # (NO PUSH UP)
052867,000512: 27,3622 75206 PUSH SIGN # TFF SQRT(MU) TO PDL+0
052868,000513: 27,3623 00017 TFFQ1 # Q1 FOR GONEPAST TEST
052869,000514: 27,3624 71244 BPL DLOAD # GONE PAST ?
052870,000515: 27,3625 57646 NEGTFF # YES. TFF < 0.
052871,000516: 27,3626 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
052872,000517: 27,3627 51076 DCOMP BPL # ALFA > 0 ?
052873,000518: 27,3630 57646 NEGTFF # NO. TFF IS NEGATIVE.
052874,000519:
052875,000520: # CORRECT FOR ORBITAL PERIOD.
052876,000521:
052877,000522: 27,3631 77676 DCOMP # YES. CORRECT FOR ORB PERIOD.
052878,000523: 27,3632 56205 DMP DDV
052879,000524: 27,3633 17756 PI/16 # 2 PI (-5)
052880,000525: 27,3634 00031 TFFRTALF # SQRT(ALFA) E:(10+NA) M:(9+NA)
052881,000526: 27,3635 53657 SL* SL*
052882,000527: 27,3636 57602 0 -4,2 # X2=-NA
052883,000528: 27,3637 57602 0 -4,2
052884,000529: 27,3640 43257 SL* DAD
052885,000530: 27,3641 57576 0,2
052886,000531: # TFF SQRT(MU) FROM PDL+0 E:(-45) M:(-42)
052887,000532: 27,3642 40005 ENDTFF DMP BOV # TFF SQRT(MU) IN MPAC E:(-45) M:(-42)
052888,000533: 27,3643 00037 TFF/RTMU # E:(17) M:(14)
052889,000534: 27,3644 57652 MAXTFF # SET POSMAX IN OVFL.
052890,000535:
052891,000536: 27,3645 77616 DUMPTFF2 RVQ # RETURN TFF (-28) CS IN MPAC.
052892,000537:
052893,000538: # Page 1277
052894,000539: 27,3646 77745 NEGTFF DLOAD
052895,000540: # TFF SQRT(MU) FROM PDL+0, NEGATIVE.
052896,000541: 27,3647 77650 GOTO
052897,000542: 27,3650 57642 ENDTFF
052898,000543:
052899,000544: 27,3651 77745 MAXTFF1 DLOAD # RESET PDL
052900,000545: 27,3652 43545 MAXTFF DLOAD RVQ
052901,000546: 27,3653 17772 NEARONE
052902,000547:
052903,000548: # TIME OF FLIGHT ELLIPSE WHEN DEL (ECCENTRIC ANOM) GEQ 90 AND LEQ -90.
052904,000549:
052905,000550: # NUM FROM TFFX. E:(-16) OR (-29)
052906,000551: # M:(-15) OR (-27)
052907,000552: 27,3654 77712 TFFELL SL2 # NUM E:(-14) OR (-27) M:(-13) OR (-25)
052908,000553: 27,3655 41465 BDDV PUSH # TEMP SAVE D/N IN PDL+0
052909,000554: # DEN FROM PDL+0 E:(-3)/(-16) M:(-3)/(-15)
052910,000555: # N/D TO PDL+0 E:(11) M:(10)
052911,000556: 27,3656 45345 TFFEL1 DLOAD DSU # (ENTER WITH D/N=0 IN PDL+0)
052912,000557: 27,3657 00045 TFFTEM # Q2 E:(-16) M:(-15)
052913,000558: 27,3660 00017 TFFQ1 # Q1 E:(-16) M:(-15)
052914,000559: 27,3661 14013 STODL TFFDELQ # Q2-Q1 E:(-16) M:(-15)
052915,000560: # D/N FROM PDL+0
052916,000561: 27,3662 77626 STADR
052917,000562: 27,3663 77732 STORE TFFTEM # D/N E:(11) M:(10)
052918,000563: 27,3664 53605 DMP SL*
052919,000564: 27,3665 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
052920,000565: 27,3666 57576 0,2 # 1/ALFA Z E:(-11-NA) M:(-10-NA)
052921,000566: 27,3667 41206 PUSH DMP # TO PDL+0
052922,000567: 27,3670 00045 TFFTEM # 1/Z E:(11) M:(10
052923,000568: 27,3671 41057 SL* BOVB
052924,000569: 27,3672 57576 0,2 # X2= -NA
052925,000570: 27,3673 21713 SIGNMPAC # IN CASE X= 1.0, CONTINUE
052926,000571: 27,3674 00043 STORE TFFX # X=1/ALFA ZSQ
052927,000572: 27,3675 41234 RTB DMP
052928,000573: 27,3676 57736 T(X) # POLY
052929,000574: 27,3677 00043 TFFX
052930,000575: 27,3700 45242 SR3 DSU
052931,000576: 27,3701 17764 DP2(-3)
052932,000577: 27,3702 41405 DMP PUSH # 2(X T(X)-1) /Z ALFA E:(-15-NA)
052933,000578: # M:(-14-NA)
052934,000579: # 1/ALFA Z FROM PDL+0 E:(-11-NA)
052935,000580: # M:(-10-NA)
052936,000581: 27,3703 41345 DLOAD DMP # GET SIGN FOR SDELF
052937,000582: 27,3704 00045 TFFTEM # 1/Z E:(11) M:(10)
052938,000583: 27,3705 00015 RMAG1 # E:(-29) M:(-27)
052939,000584: 27,3706 43312 SL2 DAD
052940,000585: 27,3707 00017 TFFQ1 # Q1 E:(-16) M:(-15)
052941,000586: 27,3710 14045 STODL TFFTEM # (Q1+R 1/Z) =SGN OF SDELF E:(-16) M:(-15)
052942,000587: 27,3711 00035 TFFNP # LC P E:(-38+2NR) M:(-36+2NR)
052943,000588: 27,3712 53605 DMP SL* # CALC FOR ARG FOR TFF/TRIG.
052944,000589: # Page 1278
052945,000590: 27,3713 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
052946,000591: 27,3714 57575 1,2 # X2=-NA
052947,000592: 27,3715 53765 SIGN SL*
052948,000593: 27,3716 00045 TFFTEM # AFFIX SIGN FOR SDELF
052949,000594: 27,3717 57576 0,2
052950,000595: 27,3720 14045 STODL TFFTEM # P/ALFA E:(-59+2NR) M:(-55+2NR)
052951,000596: # (ARG FOR USE IN TFF/TRIG)
052952,000597: 27,3721 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
052953,000598: 27,3722 41366 SQRT DMP
052954,000599: 27,3723 17756 PI/16 # PI (-4)
052955,000600: 27,3724 77615 DAD
052956,000601: # 2(XT(X)-1)/Z ALFA FROM PDL E:(-15-NA)
052957,000602: # M:(-14-NA)
052958,000603: 27,3725 45257 SL* DSU
052959,000604: 27,3726 57577 0 -1,2
052960,000605: 27,3727 00013 TFFDELQ # Q2-Q1 E:(-16) M:(-15)
052961,000606: 27,3730 53605 DMP SL*
052962,000607: 27,3731 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
052963,000608: 27,3732 57601 0 -3,2
052964,000609: 27,3733 52057 SL* GOTO
052965,000610: 27,3734 57602 0 -4,2
052966,000611: 27,3735 57642 ENDTFF # TFF SQRT(MU) IN MPAC E:(-145) M:(-42)
052967,000612:
052968,000613: # Page 1279
052969,000614: # PROGRAM NAME: T(X) DATE: 01.17.67
052970,000615: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
052971,000616: # MOD BY: RR BAIRNSFATHER
052972,000617:
052973,000618: # FUNCTIONAL DESCRIPTION: THE POLYNOMIAL T(X) IS USED BY TIME OF FLIGHT SUBROUTINES CALCTFF AND
052974,000619: # CALCTPER TO APPROXIMATE THE SERIES
052975,000620: # 2 3
052976,000621: # 1/3 -X/5 +X /7 -X /9 ...
052977,000622:
052978,000623: # WHERE X = ALFA Z Z IF ALFA Z Z LEQ 1
052979,000624: # X = 1/(ALFA Z Z) IF ALFA Z Z G 1
052980,000625:
052981,000626: # ALSO X IS NEG FOR HYPERBOLIC ORBITS
052982,000627: # X = 0 FOR PARABOLIC ORBITS
052983,000628: # X IS POSITIVE FOR ELLIPTIC ORBITS
052984,000629:
052985,000630: # FOR FLIGHT 278, THE POLYNOMIAL T(X) IS FITTED OVER THE RANGE (0,+1) AND HAS A MAXIMUM
052986,000631: # DEVIATION FROM THE SERIES OF 2 E-5. (T(X) IS A CHEBYCHEV TYPE FIT AND WAS OBTAINED USING
052987,000632: # MAX PROGRAM AUTOCURFIT294RRB AND IS VALID TO THE SAME TOLERANCE OVER THE RANGE (-.08,+1).)
052988,000633:
052989,000634: # CALLING SEQUENCE: RTB
052990,000635: # T(X)
052991,000636: # C(MPAC) = X
052992,000637:
052993,000638: # SUBROUTINE CALLED: NONE
052994,000639:
052995,000640: # NORMAL EXIT MODE: TC TANZIG
052996,000641:
052997,000642: # ALARMS: NONE
052998,000643:
052999,000644: # OUTPUT: C(MPAC) = T(X)
053000,000645:
053001,000646: # ERASABLE INITIALIZATION REQUIRED:
053002,000647: # C(MPAC) = X
053003,000648:
053004,000649: # DEBRIS: NONE
053005,000650:
053006,000651: 27,3736 07225 T(X) TC POLY
053007,000652: 27,3737 00004 DEC 4 B-14 # N-1
053008,000653: 27,3740 12525 12525 2DEC 3.333333333 E-1
053009,000654: 27,3742 71463 57703 2DEC* -1.999819135 E-1*
053010,000655: 27,3744 04423 17645 2DEC* 1.418148467 E-1*
053011,000656: 27,3746 74604 43667 2DEC* -1.01310997 E-1*
053012,000657: 27,3750 01626 37256 2DEC* 5.609004986 E-2*
053013,000658: 27,3752 77404 52071 2DEC* -1.536156925 E-2*
053014,000659:
053015,000660: 27,3754 06064 ENDT(X) TC DANZIG
053016,000661:
053017,000662: 27,3755 27,3754 TCDANZIG = ENDT(X)
053018,000663:
053019,000664: # Page 1280
053020,000665: # TFF CONSTANTS
053021,000666:
053022,000667: 32,3751 BANK 32
053023,000668:
053024,000669: 27,2000 SETLOC TOF-FF1
053025,000670: 27,2000 BANK
053026,000671:
053027,000672: # # NOTE: ADJUSTED MUE FOR NEAR EARTH TRAJ.
053028,000673: # MUE = 3.990815471 E10 # M CUBE/CS SQ
053029,000674: # RTMUE = 1.997702549 E5 B-18 # MODIFIED EARTH MU
053030,000675:
053031,000676: # # NOTE: ADJUSTED MUE FOR NEAR EARTH TRAJ.
053032,000677: # MUM = 4.902778 E8 # M CUBE/CS SQ
053033,000678: # RTMUM 2DEC* 2.21422176 E4 B-18*
053034,000679: 27,3755 06220 37553 PI/16 2DEC 3.141592653 B-4
053035,000680: 27,3757 37777 37700 LIM(-22) 2OCT 3777737700 # 1.0 -B(-22)
053036,000681: 27,3761 00000 00100 DP(-22) 2OCT 0000000100 # B(-22)
053037,000682: 27,3763 04000 00000 DP2(-3) 2DEC 1 B-3
053038,000683: 27,3765 02000 00000 DP2(-4) 2DEC 1 B-4 # 1/16
053039,000684:
053040,000685: # RPAD1 2DEC 6373338 B-29 # M (-29) = 20909901.57 FT
053041,000686: 27,3767 23,2337 RPAD1 = RPAD
053042,000687:
053043,000688: 27,3767 00305 11205 R300K 2DEC 6464778 B-29 # (-29) M
053044,000689: 27,3771 37777 37777 NEARONE 2DEC .999999999
053045,000690: 27,3773 23,2523 TFFZEROS EQUALS HI6ZEROS
053046,000691: 27,3773 23,2513 TFF1/4 EQUALS HIDP1/4
053047,000692:
End of include-file TIME_OF_FREE_FALL.agc. Parent file is MAIN.agc