Source Code
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These source-code files were from the printout at the MIT Museum, with many thanks
to Deborah Douglas, the Museum's Curator of Science and Technology, for releasing
it to us. The printout was digitally photographed by Paul Fjeld. A team of
volunteers transcribed the source code manually from these images or, where
appropriate, modified already-transcribed but similar source Luminary 131 (Apollo 13)
source code to agree with the images from the printout. Note that the page images
presented online are of reduced quality, and that higher-quality images
are available. Report any conversion errors or legibility
problems in page images to info@sandroid.org.
Notations on the program listing read, in part:GAP: ASSEMBLE REVISION 001 OF AGC PROGRAM LMY99 BY NASA 2021112-061 20'35 OCT. 28,1968Note that the date is the date of the printout, not the date of the program revision. |
054238,000002: ## Copyright: Public domain.
054239,000003: ## Filename: TIME_OF_FREE_FALL.agc
054240,000004: ## Purpose: Part of the source code for Luminary 1A build 099.
054241,000005: ## It is part of the source code for the Lunar Module's (LM)
054242,000006: ## Apollo Guidance Computer (AGC), for Apollo 11.
054243,000007: ## Assembler: yaYUL
054244,000008: ## Contact: Ron Burkey <info@sandroid.org>.
054245,000009: ## Website: www.ibiblio.org/apollo.
054246,000010: ## Pages: 1268-1283
054247,000011: ## Mod history: 2009-05-26 RSB Adapted from the corresponding
054248,000012: ## Luminary131 file, using page
054249,000013: ## images from Luminary 1A.
054250,000014: ## 2011-01-06 JL Fixed pseudo-label indentation.
054251,000015: ## 2016-12-17 RSB Proofed text comments with octopus/ProoferComments
054252,000016: ## and corrected the errors found.
054253,000017: ## 2017-03-14 RSB Comment-text fixes noted in proofing Luminary 116.
054254,000018: ## 2017-03-16 RSB Comment-text fixes identified in 5-way
054255,000019: ## side-by-side diff of Luminary 69/99/116/131/210.
054256,000020:
054257,000021: ## This source code has been transcribed or otherwise adapted from
054258,000022: ## digitized images of a hardcopy from the MIT Museum. The digitization
054259,000023: ## was performed by Paul Fjeld, and arranged for by Deborah Douglas of
054260,000024: ## the Museum. Many thanks to both. The images (with suitable reduction
054261,000025: ## in storage size and consequent reduction in image quality as well) are
054262,000026: ## available online at www.ibiblio.org/apollo. If for some reason you
054263,000027: ## find that the images are illegible, contact me at info@sandroid.org
054264,000028: ## about getting access to the (much) higher-quality images which Paul
054265,000029: ## actually created.
054266,000030: ##
054267,000031: ## Notations on the hardcopy document read, in part:
054268,000032: ##
054269,000033: ## Assemble revision 001 of AGC program LMY99 by NASA 2021112-61
054270,000034: ## 16:27 JULY 14, 1969
054271,000035:
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Page 1268 |
054273,000037: # THE TFF SUBROUTINES MAY BE USED IN EITHER EARTH OR MOON CENTERED COORDINATES. THE TFF ROUTINES NEVER
054274,000038: # KNOW WHICH ORIGIN APPLIES. IT IS THE USER WHO KNOWS, AND WHO SUPPLIES RONE, VONE AND 1/SQRT(MU) AT THE
054275,000039: # APPROPRIATE SCALE LEVEL FOR THE PROPER PRIMARY BODY.
054276,000040:
054277,000041: # EARTH ORIGIN POSITION -29 METERS
054278,000042: # VELOCITY -7 METERS/CENTISECOND
054279,000043: # 1/SQRT(MU) +17 SQRT(CS SQ/METERS CUBED)
054280,000044:
054281,000045: # MOON ORIGIN POSITION -27 METERS
054282,000046: # VELOCITY -5 METERS/CENTISECONDS
054283,000047: # 1/SQRT(MU) +14 SQRT(CS SQ/METERS CUBED)
054284,000048:
054285,000049: # ALL DATA PROVIDED TO AND RECEIVED FROM ANY TFF SUBROUTINE WILL BE AT ONE OF THE LEVELS ABOVE. IN ALL CASES,
054286,000050: # THE FREE FALL TIME IS RETURNED IN CENTISECONDS AT (-28). PROGRAM TFF/CONIC WILL GENERATE VONE/RTMU AND
054287,000051: # LEAVE IT IN VONE' AT (+10) IF EARTH ORIGIN AND (+9) IF MOON ORIGIN.
054288,000052:
054289,000053: # THE USER MUST STORE THE STATE VECTOR IN RONE, VONE AND MU IN THE FORM 1/SQRT(MU) IN TFF/RTMU
054290,000054: # AT THE PROPER SCALE BEFORE CALLING TFF/CONIC. SINCE RONE, VONE ARE IN THE EXTENDED VERB STORAGE AREA,
054291,000055: # THE USER MUST ALSO LOCK OUT THE EXTENDED VERBS, AND RELEASE THEM WHEN FINISHED.
054292,000056:
054293,000057: # PROGRAMS CALC/TFF AND CALC/TPER ASSUME THAT THE TERMINAL RADIUS IS LESS THAN THE PRESENT
054294,000058: # RADIUS. THIS RESTRICTION CAN BE REMOVED BY A 15 W CODING CHANGE, BUT AT PRESENT IT IS NOT DEEMED NECESSARY.
054295,000059:
054296,000060: # THE FOLLOWING ERASABLE QUANTITIES ARE USED BY THE TFF ROUTINES, AND ARE LOCATED IN THE PUSH LIST.
054297,000061:
054298,000062: # BELOW E: IS USED FOR EARTH ORIGIN SCALE
054299,000063: # M: IS USED FOR MOON ORIGIN SCALE
054300,000064:
054301,000065: # TFFSW = 119D BIT1 0 = CALCTFF 1 = CALCTPER
054302,000066: 10,2213 TFFDELQ = 10D # Q2-Q1 E: (-16) M: (-15)
054303,000067: 10,2213 RMAG1 = 12D # ABVAL(RN) M E: (-29) M: (-27)
054304,000068: # RPER = 14D PERIGEE RADIUS M E: (-29) M: (-27)
054305,000069: 10,2213 TFFQ1 = 14D # R.V / SQRT(MUE) E: (-16) M: (-15)
054306,000070: # SDELF/2 SIN(THETA) /2
054307,000071: 10,2213 CDELF/2 = 14D # COS(THETA) /2
054308,000072: # RAPO = 16D APOGEE RADIUS M E: (-29) M: (-27)
054309,000073: 10,2213 NRTERM = 16D # TERMINAL RADIUS M E: (-29+NR)
054310,000074: # M: (-27+NR)
054311,000075: 10,2213 RTERM = 18D # TERMINAL RADIUS M E: (-29) M: (-27)
054312,000076: 10,2213 TFFVSQ = 20D # -(V SQUARED/MU) 1/M E: (20) M: (18)
054313,000077: 10,2213 TFF1/ALF = 22D # SEMI MAJ AXIS M E: (-22-2 NA)
054314,000078: # M: (-20-2 NA)
054315,000079: 10,2213 TFFRTALF = 24D # SQRT(ALFA) E:(10+NA) M: (9+NA)
054316,000080: 10,2213 TFFALFA = 26D # ALFA 1/M E:(26-NR) M: (24-NR)
054317,000081: 10,2213 TFFNP = 28D # SEMI LATUS RECTUM M E: (-38+2 NR)
054318,000082: # M: (-36+2 NR)
054319,000083: 10,2213 TFF/RTMU = 30D # 1/SQRT(MU) E: (17) M: (14)
054320,000084: 10,2213 NRMAG = 32D # PRESENT RADIUS M E: (-29+NR)
054321,000085: # M: (-27+NR)
054322,000086: 10,2213 TFFX = 34D
054323,000087: 10,2213 TFFTEM = 36D # TEMPORARY
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Page 1269 |
054325,000089: # REGISTERS S1, S2 ARE UNTOUCHED BY ANY TFF SUBROUTINE
054326,000090: # INDEX REGISTERS X1, X2 ARE USED BY ALL TFF SUBROUTINES. THEY ARE ESTAB-
054327,000091: # LISHED IN TFF/CONIC AND MUST BE PRESERVED BETWEEN CALLS TO SUBSEQUENT
054328,000092: # SUBROUTINES.
054329,000093: # -NR C(X1) = NORM COUNT OF RMAG
054330,000094: # -NA C(X2) = NORM COUNT OF SQRT(ABS(ALFA))
054331,000095:
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Page 1270 |
054333,000097: # SUBROUTINE NAME: TFFCONIC DATE: 01.29.67
054334,000098: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
054335,000099: # MOD BY: RR BAIRNSFATHER
054336,000100: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 11 APR 67
054337,000101: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 21 NOV 67 ADD MOON MU.
054338,000102: # MOD NO: 3 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
054339,000103:
054340,000104: # FUNCTIONAL DESCRIPTION: THIS SUBROUTINE IS CALLED TO COMPUTE THOSE CONIC PARAMETERS REQUIRED BY THE TFF
054341,000105: # SUBROUTINES AND TO ESTABLISH THEM IN THE PUSH LIST AREA. THE PARAMETERS ARE LISTED UNDER OUTPUT.
054342,000106: # THE EQUATIONS ARE
054343,000107: # - - -
054344,000108: # H = RN*VN ANGULAR MOMENTUM
054345,000109: # - -
054346,000110: # LCP = H.H / MU SEMI LATUS RECTUM
054347,000111: # - -
054348,000112: # ALFA = 2/RN - VN.VN / MU RECIPROCAL SEMI MAJ AXIS, SIGNED
054349,000113:
054350,000114: # AND ALFA IS POS FOR ELLIPTIC ORBITS
054351,000115: # 0 FOR PARABOLIC ORBITS
054352,000116: # NEG FOR HYPERBOLIC ORBITS.
054353,000117: # SUBROUTINE ALSO COMPUTES AND SAVES RMAG.
054354,000118:
054355,000119: # CALLING SEQUENCE:
054356,000120: # TFFCONIC EXPECTS CALLER TO ENTER WITH CORRECT GRAVITATIONAL CONSTANT IN MPAC, IN THE FORM
054357,000121: # 1/SQRT(MU). PROGRAM WILL SAVE IN TFF/RTMU. THE SCALE IS DETERMINED BY WHETHER EARTH OR MOON
054358,000122: # ORIGIN IS USED. THE CALLER MUST LOCK OUT THE EXTENDED VERBS BEFORE PROVIDING STATE VECTOR IN RONE,
054359,000123: # VONE AT PROPER SCALE. THE EXTENDED VERBS MUST BE RESTORED WHEN THE CALLER IS FINISHED USING THE
054360,000124: # TFF ROUTINES.
054361,000125:
054362,000126: # ENTRY POINT TFFCONMU EXPECTS THAT TFF/RTMU IS ALREADY LOADED.
054363,000127:
054364,000128: # TO SPECIFY MU: DLOAD CALL IF MU ALREADY STORED: CALL
054365,000129: # YOURMU 1/RTMU E:(17) M:(14) TFFCONMU
054366,000130: # TFFCONIC
054367,000131: # PUSHLOC = PDL+0, ARBITRARY IF LEQ 18D
054368,000132:
054369,000133: # SUBROUTINES CALLED: NONE
054370,000134:
054371,000135: # NORMAL EXIT MODES: RVQ
054372,000136:
054373,000137: # ALARMS: NONE
054374,000138:
054375,000139: # OUTPUT: THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
054376,000140: # RMAG1 E:(-29) M:(-27) M RN, PRESENT RADIUS LENGTH.
054377,000141: # NRMAG E:(-29+NR) M RMAG, NORMALIZED
054378,000142: # M:(-27+NR)
054379,000143: # X1 -NR, NORM COUNT
054380,000144: # TFFNP E:(-38+2NR) M LCP, SEMI LATUS RECTUM, WEIGHTED BY NR. FOR VGAMCALC
054381,000145: # M:(-36+2NR)
054382,000146: # TFF/RTMU E:(17) M:(14) 1/SQRT(MU)
054383,000147: # TFFVSQ E:(20) M:(18) 1/M -(V SQ/MU): PRESENT VELOCITY,NORMLIZED. FOR VGAMCALC
054384,000148: # TFFALFA E:(26-NR) 1/M ALFA, WEIGHTED BY NR
054385,000149: # M:(24-NR)
054386,000150: # TFFRTALF E:(10+NA) SQRT(ALFA), NORMALIZED
054387,000151: # M:(9+NA)
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Page 1271 |
054389,000153: # X2 -NA, NORMCOUNT
054390,000154: # TFF1/ALF E:(-22-2NA) SIGNED SEMI MAJ AXIS, WEIGHTED BY NA
054391,000155: # M:(-20-2NA)
054392,000156: # PUSHLOC AT PDL+0
054393,000157:
054394,000158: # THE FOLLOWING IS STORED IN GENERAL ERASABLE
054395,000159: # VONE' E:(10) M:(9) V/RT(MU), NORMALIZED VELOCITY
054396,000160:
054397,000161: # ERASABLE INITIALIZATION REQUIRED:
054398,000162: # RONE E:(-29) M:(-27) M STATE VECTOR LEFT BY CALLER
054399,000163: # VONE E:(-7) M:(-5) M/CS STATE VECTOR LEFT BY CALLER
054400,000164: # TFF/RTMU E:(17) M:(14) 1/RT(CS SQ/M CUBE) IF ENTER VIA TFFCONMU.
054401,000165:
054402,000166: # DEBRIS: QPRET, PDL+0 ... PDL+3
054403,000167:
054404,000168: 33,3777 BANK 33
054405,000169: 27,2000 SETLOC TOF-FF
054406,000170: 27,2000 BANK
054407,000171:
054408,000172: 27,3360 COUNT* $$/TFF
054409,000173:
054410,000174: 27,3360 00037 TFFCONIC STORE TFF/RTMU # 1/SQRT(MU) E:(17) M:(14)
054411,000175:
054412,000176: 27,3361 53575 TFFCONMU VLOAD UNIT # COME HERE WITH TFFRTMU LOADED.
054413,000177: 27,3362 02207 RONE # SAVED RN. M E:(-29) M:(-27)
054414,000178: 27,3363 77725 PDDL # UR/2 TO PDL+0, +5
054415,000179: 27,3364 00045 36D # MAGNITUDE
054416,000180: 27,3365 00015 STORE RMAG1 # M E:(-29) M:(-27)
054417,000181:
054418,000182: 27,3366 77701 NORM
054419,000183: 27,3367 00047 X1 # -NR
054420,000184: 27,3370 24041 STOVL NRMAG # RMAG M E:(-29+NR) M:(-27+NR)
054421,000185: 27,3371 02215 VONE # SAVED VN. M/CS E:(-7) M:(-5)
054422,000186: 27,3372 77761 VXSC
054423,000187: 27,3373 00037 TFF/RTMU # E:(17) M:(14)
054424,000188: 27,3374 02170 STORE VONE' # VN/SQRT(MU) E:(10) M:(9)
054425,000189:
054426,000190: 27,3375 47361 VXSC VXV
054427,000191: 27,3376 00041 NRMAG # E:(-29+NR) M:(-27+NR)
054428,000192: # UR/2 FROM PDL
054429,000193: 27,3377 47572 VSL1 VSQ # BEFORE: E:(-19+NR) M:(-18+NR)
054430,000194: 27,3400 14035 STODL TFFNP # LC P M E:(-38+2NR) M:(-36+2NR)
054431,000195: # SAVE ALSO FOR VGAMCALC
054432,000196: 27,3401 06512 TFF1/4
054433,000197: 27,3402 63271 DDV PDVL # (2/RMAG) 1/M E:(26-NR) M:(24-NR)
054434,000198: 27,3403 00041 NRMAG # RMAG M E:(-29+NR) M:(-27+NR)
054435,000199: 27,3404 02170 VONE' # SAVED VN. E:(10) M:(9)
054436,000200: 27,3405 57436 VSQ DCOMP # KEEP MPAC+2 HONEST FOR SQRT.
054437,000201: 27,3406 00025 STORE TFFVSQ # -(V SQ/MU) E:(20) M:(18)
054438,000202: # SAVE FOR VGAMCALC
054439,000203: 27,3407 43257 SR* DAD
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Page 1272 |
054441,000205: 27,3410 20573 0 -6,1 # GET -VSQ/MU E:(26-NR) M:(24-NR)
054442,000206: 27,3411 77626 STADR
054443,000207: # 2/RMAG FROM PDL+2
054444,000208: 27,3412 77744 STORE TFFALFA # ALFA 1/M E:(26-NR) M:(24-NR)
054445,000209: 27,3413 41457 SL* PUSH # TEMP SAVE ALFA E:(20) M:(18)
054446,000210: 27,3414 20173 0 -6,1
054447,000211: 27,3415 75446 ABS SQRT # E:(10) M:(9)
054448,000212: 27,3416 77701 NORM
054449,000213: 27,3417 00050 X2 # X2 = -NA
054450,000214: 27,3420 00031 STORE TFFRTALF # SQRT( ABS(ALFA) ) E:(10+NA) M:(9+NA)
054451,000215: 27,3421 75316 DSQ SIGN # NOT SO ACCURATE, BUT OK
054452,000216: # ALFA FROM PDL+2 E:(20) M:(18)
054453,000217: 27,3422 55254 BZE BDDV # SET 1/ALFA =0, TO SHOW SMALL ALFA
054454,000218: 27,3423 57425 +2
054455,000219: 27,3424 06512 TFF1/4
054456,000220: 27,3425 00027 +2 STORE TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
054457,000221: 27,3426 77616 DUMPCNIC RVQ
054458,000222:
054459,000223: # 39 W
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Page 1273 |
054461,000225: # SUBROUTINE NAME: TFFRP/RA DATE: 01.17.67
054462,000226: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
054463,000227: # MOD BY: RR BAIRNSFATHER
054464,000228: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 11 APR 67
054465,000229: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
054466,000230: # ALSO IMPROVE ACCURACY OF RAPO.
054467,000231:
054468,000232: # FUNCTIONAL DESCRIPTION: USED BY CALCTPER AND TFF DISPLAYS TO CALCULATE PERIGEE RADIUS AND ALSO
054469,000233: # APOGEE RADIUS FOR A GENERAL CONIC.
054470,000234: # PROGRAM GIVES PERIGEE RADIUS AS APOGEE RADIUS IS GIVEN BY
054471,000235: # RP = P/(1+E) RA = (1+E) / ALFA
054472,000236: # WHERE 2
054473,000237: # E = 1 - P ALFA
054474,000238: # IF RA IS NEGATIVE OR SHOWS DIVIDE OVERFLOW, THEN RA = POSMAX BECAUSE
054475,000239: # 1. APOGEE RADIUS IS NOT MEANINGFUL FOR HYPERBOLA
054476,000240: # 2. APOGEE RADIUS IS NOT DEFINED FOR PARABOLA
054477,000241: # 3. APOGEE RADIUS EXCEEDS THE SCALING FOR ELLIPSE.
054478,000242:
054479,000243: # THIS SUBROUTINE REQUIRES THE SIGNED RECIPROCAL SEMI MAJ AXIS, ALFA, AND SEMI LATUS RECTUM AS DATA.
054480,000244:
054481,000245: # CALLING SEQUENCE: CALL
054482,000246: # TFFRP/RA
054483,000247: # PUSHLOC = PDL+0, ARBITRARY IF LEQ 10D
054484,000248: # C(MPAC) UNSPECIFIED
054485,000249:
054486,000250: # SUBROUTINES CALLED: NONE
054487,000251:
054488,000252: # NORMAL EXIT MODE: RVQ
054489,000253: # IF ELLIPSE, WITHIN NORMAL SCALING, RAPO IS CORRECT.
054490,000254: # OTHERWISE, RAPO = POSMAX.
054491,000255:
054492,000256: # ALARMS: NONE
054493,000257:
054494,000258: # OUTPUT: STORED IN PUSH LIST AREA. SCALE OF OUTPUT AGREES WITH DATA SUPPLIED TO TFF/CONIC.
054495,000259: # RPER E:(-29) M:(-27) M PERIGEE RADIUS DESTROYED BY CALCTFF/CALCTPER, TFFTRIG.
054496,000260: # RAPO E:(-29) M:(-27) M APOGEE RADIUS WILL BE DESTROYED BY CALCTFF/CALCTPER
054497,000261: # PUSHLOC AT PDL+0
054498,000262:
054499,000263: # ERASABLE INITIALIZATION REQUIRED:
054500,000264: # TFFALFA E:(26-NR) M 1/SEMI MAJ AXIS LEFT BY TFFCONIC
054501,000265: # M:(24-NR)
054502,000266: # TFFNP E:(-38+2NR) M LC P, SEMI LATUS RECTUM LEFT BY TFFCONIC
054503,000267: # M:(-36+2NR)
054504,000268: # X1 -NR, NORM COUNT OF RMAG LEFT BY TFFCONIC
054505,000269: # X2 -NA, NORM COUNT OF ALFA LEFT BY TFFCONIC
054506,000270:
054507,000271: # DEBRIS: QPRET, PDL+0 ... PDL+1
054508,000272:
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Page 1274 |
054510,000274: 27,3427 RAPO = 16D # APOGEE RADIUS M E:(-29) M:(-27)
054511,000275: 27,3427 RPER = 14D # PERIGEE RADIUS M E:(-29) M:(-27)
054512,000276:
054513,000277: 27,3427 41345 TFFRP/RA DLOAD DMP
054514,000278: 27,3430 00033 TFFALFA # ALFA 1/M E:(26-NR) M:(24-NR)
054515,000279: 27,3431 00035 TFFNP # LC P M E:(-38+2NR) M:(-36+2NR)
054516,000280: 27,3432 57457 SR* DCOMP # ALFA P (-12+NR)
054517,000281: 27,3433 20571 0 -8D,1 # ALFA P (-4)
054518,000282: 27,3434 51415 DAD ABS # (DCOMP GIVES VALID TP RESULT FOR SQRT)
054519,000283: # (ABS PROTECTS SQRT IF E IS VERY NEAR 0)
054520,000284: 27,3435 17765 DP2(-4)
054521,000285: 27,3436 43366 SQRT DAD # E SQ = (1- P ALFA) (-4)
054522,000286: 27,3437 06512 TFF1/4
054523,000287: 27,3440 55206 PUSH BDDV # (1+E) (-2) TO PDL+0
054524,000288: 27,3441 00035 TFFNP # LCP M E:(-38+2NR) M:(-36+2NR)
054525,000289: 27,3442 53657 SR* SR* # (DOES SR THEN SL TO AVOID OVFL)
054526,000290: 27,3443 20601 0,1 # X1=-NR
054527,000291: 27,3444 20572 0 -7,1 # (EFFECTIVE SL)
054528,000292: 27,3445 14017 STODL RPER # PERIGEE RADIUS M E:(-29) M:(-27)
054529,000293: # (1+E) (-2) FROM PDL+0
054530,000294: 27,3446 41005 DMP BOVB
054531,000295: 27,3447 00027 TFF1/ALF # E:(-22-2NA) M:(-20-2NA)
054532,000296: 27,3450 57753 TCDANZIG # CLEAR OVFIND, IF ON.
054533,000297: 27,3451 53654 BZE SL*
054534,000298: 27,3452 57461 MAXRA # SET POSMAX, IF ALFA=0
054535,000299: 27,3453 57603 0 -5,2 # -5+NA
054536,000300: 27,3454 40057 SL* BOV
054537,000301: 27,3455 57576 0,2
054538,000302: 27,3456 57461 MAXRA # SET POSMAX IF OVFL.
054539,000303: 27,3457 77644 BPL # CONTINUE WITH VALID RAPO.
054540,000304: 27,3460 57463 +3
054541,000305: 27,3461 77745 MAXRA DLOAD # RAPO CALC IS NOT VALID. SET RAPO =
054542,000306: 27,3462 17771 NEARONE # POSMAX AS A TAG.
054543,000307: 27,3463 00021 +3 STORE RAPO # APOGEE RADIUS M E:(-29) M:(-27)
054544,000308: 27,3464 77616 DUMPRPRA RVQ
054545,000309:
054546,000310: # 30 W
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Page 1275 |
054548,000312: # SUBROUTINE NAME: CALCTPER / CALCTFF DATE: 01.29.67
054549,000313: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
054550,000314: # MOD BY: RR BAIRNSFATHER
054551,000315: # MOD NO: 1 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 67
054552,000316: # MOD NO: 2 MOD BY: RR BAIRNSFATHER DATE: 14 APR 67
054553,000317: # MOD NO: 3 MOD BY: RR BAIRNSFATHER DATE: 8 JUL 67 NEAR EARTH MUE AND NEG TFF (GONEPAST)
054554,000318: # MOD NO: 4 MOD BY: RR BAIRNSFATHER DATE: 21 NOV 67 ADD VARIABLE MU.
054555,000319: # MOD NO: 5 MOD BY: RR BAIRNSFATHER DATE: 21 MAR 68 ACCEPT DIFFERENT EARTH/MOON SCALES
054556,000320:
054557,000321: # FUNCTIONAL DESCRIPTION: PROGRAM CALCULATES THE FREE-FALL TIME OF FLIGHT FROM PRESENT POSITION RN AND
054558,000322: # VELOCITY VN TO A RADIUS LENGTH SPECIFIED BY RTERM, SUPPLIED BY THE USER. THE POSITION VECTOR
054559,000323: # RN MAY BE ON EITHER SIDE OF THE CONIC, BUT RTERM IS CONSIDERED ON THE INBOUND SIDE.
054560,000324: # THE EQUATIONS ARE
054561,000325:
054562,000326: # Q2 = -SQRT(RTERM (2-RTERM ALFA) - LCP) (INBOUND SIDE)) LEQ +- LCE/SQRT(ALFA)
054563,000327: # - -
054564,000328: # Q1 = RN.VN / SQRT(MU) LEQ +- LCE/SQRT(ALFA)
054565,000329:
054566,000330: # Z = NUM / DEN LEQ +- 1/SQRT(ALFA)
054567,000331:
054568,000332: # WHERE, IF INBOUND
054569,000333: # NUM = RTERM -RN LEQ +- 2 LCE/ALFA
054570,000334: # DEN = Q2+Q1 LEQ +- 2 LCE/SQRT(ALFA)
054571,000335:
054572,000336: # AND, IF OUTBOUND
054573,000337: # NUM = Q2-Q1 LEQ +- 2 LCE/SQRT(ALFA)
054574,000338: # DEN = 2 - ALFA (RTERM + RN). LEQ +- 2 LCE
054575,000339:
054576,000340: # IF ALFA ZZ < 1.0 (FOR ALL CONICS EXCEPT ELLIPSES HAVING ABS(DEL ECC ANOM) G 90 DEG)
054577,000341: # THEN X = ALFA Z Z
054578,000342: # AND TFF = (RTERM +RN -2 ZZ T(X) ) Z/SQRT(MU)
054579,000343: # EXCEPT IF ALFA PNZ, AND IF TFF NEG,
054580,000344: # THEN TFF = 2 PI /(ALFA SQRT(ALFA)) + TFF
054581,000345: # OR IF ALFA ZZ GEQ 1.0 (FOR ELLIPSES HAVING ABS(DEL ECC ANOM) GEQ 90 DEG)
054582,000346: # THEN X = 1/ALFA Z Z
054583,000347: # AND TFF = (PI/SQRT(ALFA) -Q2 +Q1 +2(X T(X) -1) /ALFA Z) /ALFA SQRT(MU)
054584,000348: # WHERE T(X) IS A POLYNOMIAL APPROXIMATION TO THE SERIES
054585,000349: # 2 3 2
054586,000350: # 1/3 - X/5 + X /7 - X /9 ... (X < 1.0)
054587,000351:
054588,000352: # CALLING SEQUENCE: TIME TO RTERM TIME TO PERIGEE
054589,000353: # CALL CALL
054590,000354: # CALCTFF CALCTPER
054591,000355: # C(MPAC) = TERMNL RAD M C(MPAC) = PERIGEE RAD M
054592,000356: # FOR EITHER, E:(-29) M:(-27)
054593,000357: # FOR EITHER, PUSHLOC = PDL+0, ARBITRARY IF LEQ 8D.
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Page 1276 |
054595,000359:
054596,000360: # SUBROUTINES CALLED: T(X), VIA RTB
054597,000361:
054598,000362: # NORMAL EXIT MODE: RVQ
054599,000363: # HOWEVER, PROGRAM EXITS WITH ONE OF THE FOLLOWING VALUES FOR TFF (-28) CS IN MPAC. USER MUST STORE.
054600,000364: # A. TFF = FLIGHT TIME. NORMAL CASE FOR POSITIVE FLIGHT TIME LESS THAN ONE ORBITAL PERIOD.
054601,000365: # B. (THIS OPTION IS NO LONGER USED.)
054602,000366: # C. TFF = POSMAX. THIS INDICATES THAT THE CONIC FROM THE PRESENT POSITION WILL NOT RETURN TO
054603,000367: # THE SPECIFIED ALTITUDE. ALSO INDICATES OUTBOUND PARABOLA OR HYPERBOLA.
054604,000368:
054605,000369: # OUTPUT: C(MPAC) (-28) CS TIME OF FLIGHT, OR TIME TO PERIGEE
054606,000370: # TFFX (0) X, LEFT FOR ENTRY DISPLAY TFF ROUTINES
054607,000371: # NRTERM E:(-29+NR) M RTERM, WEIGHTED BY NR LEFT FOR ENTRY DISPLAY TFF ROUTINES
054608,000372: # M:(-27+NR)
054609,000373: # TFFTEM E:(-59+2NR) LCP Z Z SGN(SDELF) LEFT FOR ENTRY DISPLAY TFF ROUTINES
054610,000374: # M:(-55+2NR) LCP /ALFA SGN(SDELF) LEFT FOR ENTRY DISPLAY TFF ROUTINES
054611,000375: # NOTE: TFFTEM = PDL 36D AND WILL BE DESTROYED BY .:UNIT:.
054612,000376: # RMAG1 E:(-29) M:(-27) PDL 12 NOT TOUCHED.
054613,000377: # TFFQ1 E:(-16) M:(-15) PDL 14D
054614,000378: # TFFDELQ E:(-16) M:(-15) PDL 10D
054615,000379: # PUSHLOC AT PDL+0
054616,000380:
054617,000381: # ERASABLE INITIALIZATION REQUIRED:
054618,000382: # RONE E:(-29) M:(-27) M STATE VECTOR LEFT BY USER
054619,000383: # VONE' E:(+10) M:(+9) VN/SQRT(MU) LEFT BY TFF/CONIC
054620,000384: # RMAG1 E:(-29) M:(-27) PRESENT RADIUS, M LEFT BY TFFCONIC
054621,000385: # C(MPAC) E:(-29) M:(-27) RTERM, TERMINAL RADIUS LENGTH, M LEFT BY USER
054622,000386:
054623,000387: # THE FOLLOWING ARE STORED IN THE PUSH LIST AREA.
054624,000388: # TFF/RTMU E:(17) M:(14) 1/SQRT(MU) LEFT BY TFFCONIC.
054625,000389: # NRMAG E:(-29+NR) M RMAG, NORMALIZED LEFT BY TFFCONIC
054626,000390: # M:(-27+NR)
054627,000391: # X1 -NR, NORM COUNT LEFT BY TFFCONIC
054628,000392: # TFFNP E:(-38+2NR) M LCP, SEMI LATUS RECTUM, WEIGHT NR LEFT BY TFFCONIC
054629,000393: # M:(-36+2NR)
054630,000394: # TFFALFA E:(26-NR) 1/M ALFA, WEIGHT NR LEFT BY TFFCONIC
054631,000395: # M:(24-NR)
054632,000396: # TFFRTALF E:(10+NA) SQRT(ALFA), NORMALIZED LEFT BY TFFCONIC
054633,000397: # M:(9+NA)
054634,000398: # X2 -NA, NORMCOUNT LEFT BY TFFCONIC
054635,000399: # TFF1/ALF E:(-22-2NA) SIGNED SEMIMAJ AXIS, WEIGHTED BY NA LEFT BY TFFCONIC
054636,000400: # M:(-20-2NA)
054637,000401:
054638,000402: # DEBRIS: QPRET, PDL+0 ... PDL+3
054639,000403: # RTERM E:(-29) M:(-27) RTERM, TERMINAL RADIUS LENGTH
054640,000404: # RAPO E:(-29) M:(-27) PDL 16D (=NRTERM)
054641,000405: # RPER E:(-29) M:(-27) PDL 14D (=TFFQ1)
054642,000406:
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Page 1277 |
054644,000408: 27,3465 77614 CALCTPER SETGO # ENTER WITH RPER IN MPAC
054645,000409: 27,3466 03436 TFFSW
054646,000410: 27,3467 57472 +3
054647,000411: 27,3470 77614 CALCTFF CLEAR # ENTER WITH RTERM IN MPAC
054648,000412: 27,3471 03676 TFFSW
054649,000413: 27,3472 00023 +3 STORE RTERM # E:(-29) M:(-27)
054650,000414: 27,3473 77657 SL*
054651,000415: 27,3474 20201 0,1 # X1=-NR
054652,000416: 27,3475 00021 STORE NRTERM # RTERM E:(-29+NR) M:(-27+NR)
054653,000417: 27,3476 44205 DMP BDSU
054654,000418: 27,3477 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
054655,000419: 27,3500 06512 TFF1/4
054656,000420: 27,3501 41206 PUSH DMP # (2-ALFA RTERM) (-3) TO PDL+0
054657,000421: 27,3502 00021 NRTERM # E:(-29+NR) M:(-27+NR)
054658,000422: 27,3503 53725 PDDL SR* # RTERM(2-ALFA RTERM) TO PDL+2
054659,000423: # E:(-32+NR) M:(-30+NR)
054660,000424: 27,3504 00035 TFFNP # LC P E:(-38+2NR) M:(-36+2NR)
054661,000425: 27,3505 20573 0 -6,1 # X1 = -NR
054662,000426: 27,3506 43276 DCOMP DAD # DUE TO SHIFTS, KEEP PRECISION FOR SQRT
054663,000427: # RTERM(2-ALFA RTERM) FROM PDL +2
054664,000428: # E:(-32+NR) M:(-30+NR)
054665,000429: 27,3507 77657 SR* # LEAVE E:(-32) M:(-30)
054666,000430: 27,3510 20601 0,1 # X1 = -NR
054667,000431: 27,3511 71214 BOFF DLOAD # CHECK TFF /TPER SWITCH
054668,000432: 27,3512 03756 TFFSW
054669,000433: 27,3513 57515 +2 # IF TFF, CONTINUE
054670,000434: 27,3514 06522 TFFZEROS # IF TPER, SET Q2 = 0
054671,000435: 27,3515 75440 +2 BMN SQRT # E:(-16) M:(-15)
054672,000436:
054673,000437: 27,3516 57650 MAXTFF1 # NO FREE FALL CONIC TO RTERM FROM HERE
054674,000438: # RESET PDL, SET TFF=POSMAX, AND EXIT.
054675,000439:
054676,000440: 27,3517 41076 DCOMP BOVB # RT IS ON INBOUND SIDE. ASSURE OVFIND=0
054677,000441: 27,3520 57753 TCDANZIG # ANY PORT IN A STORM.
054678,000442: 27,3521 24045 STOVL TFFTEM # Q2 E:(-16) M:(-15)
054679,000443: 27,3522 02170 VONE' # VN/SQRT(MU) E:(10) M:(9)
054680,000444: 27,3523 52441 DOT SL3
054681,000445: 27,3524 02207 RONE # SAVED RN. E:(-29) M:(-27)
054682,000446: 27,3525 00017 STORE TFFQ1 # Q1, SAVE FOR GONEPAST TEST.
054683,000447: # E:(-16) M:(-15)
054684,000448: 27,3526 44240 BMN BDSU
054685,000449: 27,3527 57550 INBOUND # USE ALTERNATE Z
054686,000450: 27,3530 00045 TFFTEM # Q2 E:(-16) M:(-15)
054687,000451:
054688,000452: # OUTBOUND Z CALC CONTINUES HERE
054689,000453:
054690,000454: 27,3531 14043 STODL TFFX # NUM=Q2-Q1 E:(-16) M:(-15)
054691,000455: 27,3532 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
054692,000456: 27,3533 44205 DMP BDSU
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Page 1278 |
054694,000458: 27,3534 00041 NRMAG # RMAG E:(-29+NR) M:(-27+NR)
054695,000459: # (2-RTERM ALFA) (-3) FROM PDL+0
054696,000460: 27,3535 51406 SAVEDEN PUSH ABS # DEN TO PDL+0 E:(-3) OR (-16)
054697,000461: # M:(-3) OR (-15)
054698,000462: 27,3536 40015 DAD BOV # INDETERMINANCY TEST
054699,000463: 27,3537 17757 LIM(-22) # =1.0-B(-22)
054700,000464: 27,3540 57561 TFFXTEST # GO IF DEN >/= B(-22)
054701,000465: 27,3541 65345 DLOAD PDDL # SET DEN=0 OTHERWISE
054702,000466: 27,3542 06522 TFFZEROS
054703,000467: # XCH ZERO WITH PDL+0
054704,000468: 27,3543 57545 DLOAD DCOMP
054705,000469: 27,3544 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
054706,000470: 27,3545 71240 BMN DLOAD # FOR TPER: Z INDET AT DELE/2=0 AND 90.
054707,000471: 27,3546 57655 TFFEL1 # ASSUME 90, AND LEAVE 0 IN PDL: 1/Z=D/N
054708,000472:
054709,000473: # Z INDET. AT PERIGEE FOR PARAB OR HYPERB.
054710,000474: 27,3547 77616 DUMPTFF1 RVQ # RETURN TFF =0
054711,000475:
054712,000476: # INBOUND Z CALC CONTINUES HERE
054713,000477:
054714,000478: 27,3550 77745 INBOUND DLOAD # RESET PDL+0
054715,000479: 27,3551 45345 DLOAD DSU # ALTERNATE Z CALC
054716,000480: 27,3552 00023 RTERM # E:(-29) M:(-27)
054717,000481: 27,3553 00015 RMAG1 # E:(-29) M:(-27)
054718,000482: 27,3554 14043 STODL TFFX # NUM=RTERM-RN E:(-29) M:(-27)
054719,000483: 27,3555 00045 TFFTEM # Q2 E:(-16) M:(-15)
054720,000484: 27,3556 52015 DAD GOTO
054721,000485: 27,3557 00017 TFFQ1 # Q1 E:(-16) M:(-15)
054722,000486: 27,3560 57535 SAVEDEN # DEN = Q2+Q1 E:(-16) M:(-15)
054723,000487:
054724,000488: 27,3561 65215 TFFXTEST DAD PDDL # (ABS(DEN) TO PDL+2)) E:(-3) OR (-16)
054725,000489: # M:(-3) OR (-15)
054726,000490: 27,3562 17761 DP(-22) # RESTORE ABS(DEN) TO MPAC
054727,000491: 27,3563 00043 TFFX # NUM E:(-16) OR (-29) M:(-15) OR (-27)
054728,000492: 27,3564 53605 DMP SR*
054729,000493: 27,3565 00031 TFFRTALF # SQRT(ALFA) E:(10+NA) M:(9+NA)
054730,000494: 27,3566 57201 0 -3,2 # X2=-NA
054731,000495: 27,3567 77671 DDV # C(MPAC) =NUM SQRT(ALFA) E:(-3) OR (-16)
054732,000496: # M:(-3) OR (-15)
054733,000497: # ABS(DEN) FROM PDL+2 E:(-3) OR (-16)
054734,000498: # M:(-3) OR (-15)
054735,000499: 27,3570 40145 DLOAD BOV # (THE DLOAD IS SHARED WITH TFFELL)
054736,000500: 27,3571 00043 TFFX # NUM E:(-16) OR (-29) M:(-15) OR (-27)
054737,000501: 27,3572 57653 TFFELL # USE EQN FOR DELE GEQ 90, LEQ -90
054738,000502:
054739,000503: # OTHERWISE, CONTINUE FOR GENERAL CONIC FOR TFF EQN
054740,000504:
054741,000505: 27,3573 45471 DDV STADR
054742,000506: # DEN FROM PDL+0 E:(-3) OR (-16)
054743,000507: # M:(-3) OR (-15)
054744,000508: 27,3574 77732 STORE TFFTEM # Z SAVE FOR SIGN OF SDELF.
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Page 1279 |
054746,000510: # E:(-13) M:(-12)
054747,000511: 27,3575 63406 PUSH DSQ # Z TO PDL+0
054748,000512: 27,3576 41206 PUSH DMP # Z SQ TO PDL+2 E:(-26) M:(-24)
054749,000513: 27,3577 00035 TFFNP # LC P E:(-38+2NR) M:(-36+2NR)
054750,000514: 27,3600 75261 SL SIGN
054751,000515: 27,3601 20206 5
054752,000516: 27,3602 00045 TFFTEM # AFFIX SIGN FOR SDELF (ENTRY DISPLAY)
054753,000517: 27,3603 14045 STODL TFFTEM # P ZSQ E:(-59+2NR) M:(-55+2NR)
054754,000518: # (ARG IS USED IN TFF/TRIG)
054755,000519: # ZSQ FROM PDL+2 E:(-26) M:(-24)
054756,000520: 27,3604 41206 PUSH DMP # RESTORE PUSH LOC
054757,000521: 27,3605 00033 TFFALFA # ALFA E:(26-NR) M:(24-NR)
054758,000522: 27,3606 77657 SL*
054759,000523: 27,3607 20201 0,1 # X1=-NR
054760,000524: 27,3610 00043 STORE TFFX # X
054761,000525: 27,3611 41234 RTB DMP
054762,000526: 27,3612 57735 T(X) # POLY
054763,000527: # ZSQ FROM PDL+2 E:(-26) M:(-24)
054764,000528: 27,3613 44302 SR2 BDSU # 2 ZSQ T(X) E:(-29) M:(-27)
054765,000529: 27,3614 00023 RTERM # RTERM E:(-29) M:(-27)
054766,000530: 27,3615 41215 DAD DMP
054767,000531: 27,3616 00015 RMAG1 # E:(-29) M:(-27)
054768,000532: # Z FROM PDL+0 E:(-13) M:(-12)
054769,000533: 27,3617 51042 SR3 BPL # TFF SQRT(MU) E:(-45) M:(-42)
054770,000534: 27,3620 57641 ENDTFF # (NO PUSH UP)
054771,000535: 27,3621 75206 PUSH SIGN # TFF SQRT(MU) TO PDL+0
054772,000536: 27,3622 00017 TFFQ1 # Q1 FOR GONEPAST TEST
054773,000537: 27,3623 71244 BPL DLOAD # GONE PAST ?
054774,000538: 27,3624 57645 NEGTFF # YES. TFF < 0.
054775,000539: 27,3625 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
054776,000540: 27,3626 51076 DCOMP BPL # ALFA > 0 ?
054777,000541: 27,3627 57645 NEGTFF # NO. TFF IS NEGATIVE.
054778,000542:
054779,000543: # CORRECT FOR ORBITAL PERIOD.
054780,000544:
054781,000545: 27,3630 77676 DCOMP # YES. CORRECT FOR ORB PERIOD.
054782,000546: 27,3631 56205 DMP DDV
054783,000547: 27,3632 17755 PI/16 # 2 PI (-5)
054784,000548: 27,3633 00031 TFFRTALF # SQRT(ALFA) E:(10+NA) M:(9+NA)
054785,000549: 27,3634 53657 SL* SL*
054786,000550: 27,3635 57602 0 -4,2 # X2=-NA
054787,000551: 27,3636 57602 0 -4,2
054788,000552: 27,3637 43257 SL* DAD
054789,000553: 27,3640 57576 0,2
054790,000554: # TFF SQRT(MU) FROM PDL+0 E:(-45) M:(-42)
054791,000555: 27,3641 40005 ENDTFF DMP BOV # TFF SQRT(MU) IN MPAC E:(-45) M:(-42)
054792,000556: 27,3642 00037 TFF/RTMU # E:(17) M:(14)
054793,000557: 27,3643 57651 MAXTFF # SET POSMAX IF OVFL.
054794,000558:
054795,000559: 27,3644 77616 DUMPTFF2 RVQ # RETURN TFF (-28) CS IN MPAC.
054796,000560:
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Page 1280 |
054798,000562: 27,3645 77745 NEGTFF DLOAD
054799,000563: # TFF SQRT(MU) FROM PDL+0, NEGATIVE.
054800,000564: 27,3646 77650 GOTO
054801,000565: 27,3647 57641 ENDTFF
054802,000566:
054803,000567: 27,3650 77745 MAXTFF1 DLOAD # RESET PDL
054804,000568: 27,3651 43545 MAXTFF DLOAD RVQ
054805,000569: 27,3652 17771 NEARONE
054806,000570:
054807,000571: # TIME OF FLIGHT ELLIPSE WHEN DEL (ECCENTRIC ANOM) GEQ 90 AND LEQ -90.
054808,000572:
054809,000573: # NUM FROM TFFX. E:(-16) OR (-29)
054810,000574: # M:(-15) OR (-27)
054811,000575: 27,3653 77712 TFFELL SL2 # NUM E:(-14) OR (-27) M:(-13) OR (-25)
054812,000576: 27,3654 41465 BDDV PUSH # TEMP SAVE D/N IN PDL+0
054813,000577: # DEN FROM PDL+0 E:(-3)/( 16) M:(-3)/(-15)
054814,000578: # N/D TO PDL+0 E:(11) M:(10)
054815,000579: 27,3655 45345 TFFEL1 DLOAD DSU # (ENTER WITH D/N=0 IN PDL+0)
054816,000580: 27,3656 00045 TFFTEM # Q2 E:(-16) M:(-15)
054817,000581: 27,3657 00017 TFFQ1 # Q1 E:(-16) M:(-15)
054818,000582: 27,3660 14013 STODL TFFDELQ # Q2-Q1 E:(-16) M:(-15)
054819,000583: # D/N FROM PDL+0
054820,000584: 27,3661 77626 STADR
054821,000585: 27,3662 77732 STORE TFFTEM # D/N E:(11) M:(10)
054822,000586: 27,3663 53605 DMP SL*
054823,000587: 27,3664 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
054824,000588: 27,3665 57576 0,2 # 1/ALFA Z E:(-11-NA) M:(-10-NA)
054825,000589: 27,3666 41206 PUSH DMP # TO PDL+0
054826,000590: 27,3667 00045 TFFTEM # 1/Z E:(11) M:(10)
054827,000591: 27,3670 41057 SL* BOVB
054828,000592: 27,3671 57576 0,2 # X2= -NA
054829,000593: 27,3672 21712 SIGNMPAC # IN CASE X= 1.0, CONTINUE
054830,000594: 27,3673 00043 STORE TFFX # X=1/ALFA ZSQ
054831,000595: 27,3674 41234 RTB DMP
054832,000596: 27,3675 57735 T(X) # POLY
054833,000597: 27,3676 00043 TFFX
054834,000598: 27,3677 45242 SR3 DSU
054835,000599: 27,3700 17763 DP2(-3)
054836,000600: 27,3701 41405 DMP PUSH # 2(X T(X)-1) /Z ALFA E:(-15-NA)
054837,000601: # M:(-14-NA)
054838,000602: # 1/ALFA Z FROM PDL+0 E:(-11-NA)
054839,000603: # M:(-10-NA)
054840,000604: 27,3702 41345 DLOAD DMP # GET SIGN FOR SDELF
054841,000605: 27,3703 00045 TFFTEM # 1/Z E:(11) M:(10)
054842,000606: 27,3704 00015 RMAG1 # E:(-29) M:(-27)
054843,000607: 27,3705 43312 SL2 DAD
054844,000608: 27,3706 00017 TFFQ1 # Q1 E:(-16) M:(-15)
054845,000609: 27,3707 14045 STODL TFFTEM # (Q1+R 1/Z) =SGN OF SDELF E:(-16) M:(-15
054846,000610: 27,3710 00035 TFFNP # LC P E:(-38+2NR) M:(-36+2NR)
054847,000611: 27,3711 53605 DMP SL* # CALC FOR ARG FOR TFF/TRIG.
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Page 1281 |
054849,000613: 27,3712 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
054850,000614: 27,3713 57575 1,2 # X2=-NA
054851,000615: 27,3714 53765 SIGN SL*
054852,000616: 27,3715 00045 TFFTEM # AFFIX SIGN FOR SDELF
054853,000617: 27,3716 57576 0,2
054854,000618: 27,3717 14045 STODL TFFTEM # P/ALFA E:(-59+2NR) M:(-55+2NR)
054855,000619: # (ARG FOR USE IN TFF/TRIG)
054856,000620: 27,3720 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
054857,000621: 27,3721 41366 SQRT DMP
054858,000622: 27,3722 17755 PI/16 # PI (-4)
054859,000623: 27,3723 77615 DAD
054860,000624: # 2(XT(X)-1)/Z ALFA FROM PDL E:(-15-NA)
054861,000625: # M:(-14-NA)
054862,000626: 27,3724 45257 SL* DSU
054863,000627: 27,3725 57577 0 -1,2
054864,000628: 27,3726 00013 TFFDELQ # Q2-Q1 E:(-16) M:(-15)
054865,000629: 27,3727 53605 DMP SL*
054866,000630: 27,3730 00027 TFF1/ALF # 1/ALFA E:(-22-2NA) M:(-20-2NA)
054867,000631: 27,3731 57601 0 -3,2
054868,000632: 27,3732 52057 SL* GOTO
054869,000633: 27,3733 57602 0 -4,2
054870,000634: 27,3734 57641 ENDTFF # TFF SQRT(MU) IN MPAC E:(-45) M:(-42)
054871,000635:
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Page 1282 |
054873,000637: # PROGRAM NAME: T(X) DATE: 01.17.67
054874,000638: # MOD NO: 0 LOG SECTION: TIME OF FREE FALL
054875,000639: # MOD BY: RR BAIRNSFATHER
054876,000640:
054877,000641: # FUNCTIONAL DESCRIPTION: THE POLYNOMIAL T(X) IS USED BY TIME OF FLIGHT SUBROUTINES CALCTFF AND
054878,000642: # CALCTPER TO APPROXIMATE THE SERIES
054879,000643: # 2 3
054880,000644: # 1/3 -X/5 +X /7 -X /9 ...
054881,000645:
054882,000646: # WHERE X = ALFA Z Z IF ALFA Z Z LEQ 1
054883,000647: # X = 1/(ALFA Z Z) IF ALFA Z Z G 1
054884,000648:
054885,000649: # ALSO X IS NEG FOR HYPERBOLIC ORBITS
054886,000650: # X = 0 FOR PARABOLIC ORBITS
054887,000651: # X IS POSITIVE FOR ELLIPTIC ORBITS
054888,000652:
054889,000653: # FOR FLIGHT 278, THE POLYNOMIAL T(X) IS FITTED OVER THE RANGE (0,+1) AND HAS A MAXIMUM
054890,000654: # DEVIATION FROM THE SERIES OF 2 E-5 (T(X) IS A CHEBYCHEV TYPE FIT AND WAS OBTAINED USING
054891,000655: # MAC PROGRAM AUTCURFIT294RRB AND IS VALID TO THE SAME TOLERANCE OVER THE RANGE (-.08,+1).)
054892,000656:
054893,000657: # CALLING SEQUENCE: RTB
054894,000658: # T(X)
054895,000659: # C(MPAC) = X
054896,000660:
054897,000661: # SUBROUTINES CALLED: NONE
054898,000662:
054899,000663: # NORMAL EXIT MODE: TC DANZIG
054900,000664:
054901,000665: # ALARMS: NONE
054902,000666:
054903,000667: # OUTPUT: C(MPAC) = T(X)
054904,000668:
054905,000669: # ERASABLE INITIALIZATION REQUIRED:
054906,000670: # C(MPAC) = X
054907,000671:
054908,000672: # DEBRIS: NONE
054909,000673:
054910,000674: 27,3735 07222 T(X) TC POLY
054911,000675: 27,3736 00004 DEC 4 B-14 # N-1
054912,000676: 27,3737 12525 12525 2DEC 3.333333333 E-1
054913,000677:
054914,000678: 27,3741 71463 57703 2DEC* -1.999819135 E-1*
054915,000679:
054916,000680: 27,3743 04423 17645 2DEC* 1.418148467 E-1*
054917,000681:
054918,000682: 27,3745 74604 43667 2DEC* -1.01310997 E-1*
054919,000683:
054920,000684: 27,3747 01626 37256 2DEC* 5.609004986 E-2*
054921,000685:
054922,000686: 27,3751 77404 52071 2DEC* -1.536156925 E-2*
054923,000687:
054924,000688: 27,3753 06061 ENDT(X) TC DANZIG
054925,000689:
054926,000690: 27,3754 27,3753 TCDANZIG = ENDT(X)
054927,000691:
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Page 1283 |
054929,000693: # TFF CONSTANTS
054930,000694:
054931,000695: 32,3773 BANK 32
054932,000696:
054933,000697: 27,2000 SETLOC TOF-FF1
054934,000698: 27,2000 BANK
054935,000699:
054936,000700: # NOTE _ NOTE _ ADJUSTED MUE FOR NEAR EARTH TRAJ.
054937,000701: # MUE = 3.990815471 E10 M CUBE/CS SQ
054938,000702: # RTMUE = 1.997702549 E5 B-18* MODIFIED EARTH MU
054939,000703:
054940,000704: # NOTE _ NOTE _ ADJUSTED MUE FOR NEAR EARTH TRAJ.
054941,000705: # MUM = 4.902778 E8 M CUBE/CS SQ
054942,000706: # RTMUM 2DEC* 2.21422176 E4 B-18*
054943,000707:
054944,000708: 27,3754 06220 37553 PI/16 2DEC 3.141592653 B-4
054945,000709:
054946,000710: 27,3756 37777 37700 LIM(-22) 2OCT 3777737700 # 1.0 -B(-22)
054947,000711:
054948,000712: 27,3760 00000 00100 DP(-22) 2OCT 0000000100 # B(-22)
054949,000713:
054950,000714: 27,3762 04000 00000 DP2(-3) 2DEC 1 B-3
054951,000715:
054952,000716: 27,3764 02000 00000 DP2(-4) 2DEC 1 B-4 # 1/16
054953,000717:
054954,000718: # RPAD1 2DEC 6373338 B-29 M (-29) = 20909901.57 FT
054955,000719:
054956,000720: 27,3766 23,2314 RPAD1 = RPAD
054957,000721:
054958,000722: 27,3766 00305 11205 R300K 2DEC 6464778 B-29 # (-29) M
054959,000723:
054960,000724: 27,3770 37777 37777 NEARONE 2DEC .999999999
054961,000725:
054962,000726: 27,3772 23,2521 TFFZEROS EQUALS HI6ZEROS
054963,000727: 27,3772 23,2511 TFF1/4 EQUALS HIDP1/4
054964,000728:
End of include-file TIME_OF_FREE_FALL.agc. Parent file is MAIN.agc