Source Code
037130,000001: # Copyright: Public domain.
037131,000002: # Filename: ENTRY_LEXICON.agc
037132,000003: # Purpose: Part of the source code for Comanche, build 055. It
037133,000004: # is part of the source code for the Command Module's
037134,000005: # (CM) Apollo Guidance Computer (AGC), Apollo 11.
037135,000006: # Assembler: yaYUL
037136,000007: # Reference: pp. 837-843
037137,000008: # Contact: Ron Burkey <info@sandroid.org>
037138,000009: # Website: http://www.ibiblio.org/apollo.
037139,000010: # Mod history: 2009-05-12 RSB Adapted from Colossus249 file of the same
037140,000011: # name and Comanche 055 page images.
037141,000012:
037142,000013: # The contents of the "Comanche055" files, in general, are transcribed
037143,000014: # from scanned documents.
037144,000015:
037145,000016: # Assemble revision 055 of AGC program Comanche by NASA
037146,000017: # 2021113-051. April 1, 1969.
037147,000018:
037148,000019: # This AGC program shall also be referred to as Colossus 2A
037149,000020:
037150,000021: # Prepared by
037151,000022: # Massachussets Institute of Technology
037152,000023: # 75 Cambridge Parkway
037153,000024: # Cambridge, Massachusetts
037154,000025:
037155,000026: # under NASA contract NAS 9-4065.
037156,000027:
037157,000028: # Refer directly to the online document mentioned above for further
037158,000029: # information. Please report any errors to info@sandroid.org.
037159,000030:
037160,000031: # Page 837
037161,000032: # VARIABLE DESCRIPTION MAXIMUM VALUE * COMPUTER NAME
037162,000033: # -------- ----------- --------------- -------------
037163,000034: # _
037164,000035: # URT0 INITIAL TARGET VECTOR 2 (UNIT VECTOR) = RTINIT
037165,000036: # _
037166,000037: # UZ UNIT VECTOR NORTH 1 = UNITW
037167,000038: # _
037168,000039: # V VELOCITY VECTOR 2 VSAT = VEL
037169,000040: # _
037170,000041: # R POSITION VECTOR 2 EXP 29 METERS = RN
037171,000042: # _
037172,000043: # VI INERTIAL VELOCITY 128 M/CENTISEC = VN
037173,000044: # _
037174,000045: # RTE VECTOR EAST AT INITIAL TARGET 2 = RTEAST
037175,000046: # _
037176,000047: # UTR NORMAL TO RTE AND UZ 2 = RTNORM
037177,000048: # _
037178,000049: # URT TARGET VECTOR 2 = RT
037179,000050: # _
037180,000051: # UNI UNIT NORMAL TO TRAJECTORY PLANE 2
037181,000052: # _
037182,000053: # DELV INTEGRATED ACCEL. FROM PIPAS 5.85 16384 CM/S
037183,000054: # _
037184,000055: # G GRAVITY VECTOR 128 M/CENTISEC = GDT/2
037185,000056:
037186,000057: # A0 INITIAL DRAG FOR UPCONTRL 805 FPSS FPSS=FT/SEC/SEC
037187,000058:
037188,000059: # AHOOKDV TERM IN GAMMAL CALC. = AHOOK DVL 16
037189,000060:
037190,000061: # A1 DRAG VALUE IN FACTOR CALCULATION 805 FPSS
037191,000062:
037192,000063: # ALP CONST FOR UPCONTRL 1
037193,000064:
037194,000065: # ASKEP KEPLER RANGE 21600 NM NM = NAUTICAL MILE
037195,000066:
037196,000067: # ASP1 FINAL PHASE RANGE 21600 NM
037197,000068:
037198,000069: # ASPUP UP-RANGE 21600 NM
037199,000070:
037200,000071: # ASP3 GAMMA CORRECTION 21600 NM
037201,000072:
037202,000073: # ASPDWN RANGE DOWN TO PULL-UP 21600 NM
037203,000074:
037204,000075: # ASP PREDICTED RANGE 21600 NM NOT STORED
037205,000076:
037206,000077: # COSG COSINE(GAMMAL) 2 = COSG/2
037207,000078:
037208,000079: # C/D0 RECIPROCAL DRAG, -4/D0 B-8 64/FPSS
037209,000080:
037210,000081: # D TOTAL ACCELERATION 805 FPSS
037211,000082:
037212,000083: # D0 CONTROLLED CONSTANT D 805 FPSS
037213,000084:
037214,000085: # DHOOK TERM IN GAMMAL COMPUTATION 805 FPSS
037215,000086:
037216,000087: # DIFF THETNM-ASP (RANGE DIFFERENCE) 21600 NM
037217,000088:
037218,000089: # DIFFOLD PREVIOUS VALUE OF DIFF 21600 NM
037219,000090:
037220,000091: # DLEWD CHANGE IN LEWD 1
037221,000092:
037222,000093: # DR REFERENCE DRAG FOR DOWNCONTROL 805 FPSS NOT STORED
037223,000094:
037224,000095: # DREFR REFERENCE DRAG 805 FPSS NOT STORED
037225,000096:
037226,000097: # DVL VS1-VL 2 VSAT
037227,000098:
037228,000099: # E ECCENTRICITY 4 NOT STORED
037229,000100:
037230,000101: # F1 DRANGE/D DRAG (FINAL PHASE) 2700/805 = FX +5
037231,000102:
037232,000103: # F2 DRANGE/D RDOT (FINAL PHASE) 2700/2VS NM/FPS = FX +4
037233,000104: # Page 838
037234,000105:
037235,000106: # F3 DRANGE/D (L/D) 2700 NM = FX
037236,000107:
037237,000108: # FACT1 CONST FOR UPCONTRL 805 FPSS
037238,000109:
037239,000110: # FACT2 CONST FOR UPCONTRL 1/805 FPSS
037240,000111:
037241,000112: # FACTOR USED IN UPCONTRL 1 * MAXIMUM VALUE DENOTES UNSCALED
037242,000113: # VARIABLE VALUE WHEN SCALED
037243,000114: # GAMMAL FLIGHT PATH ANGLE AT VL 1 RADIAN VARIABLE HAS MAXIMUM VALUE OF ONE.
037244,000115:
037245,000116: # GAMMAL1 SIMPLE FORM OF GAMMAL 1 RADIAN
037246,000117: # Page 839
037247,000118:
037248,000119: # HEADSUP INDICATOR FOR INITIAL ROLL 1
037249,000120:
037250,000121: # KA DRAG TO LIFT UP IF DOWN 805 FPSS = KAT
037251,000122:
037252,000123: # KLAT LATERAL SWITCH GAIN 1 (NOM = .0125)
037253,000124:
037254,000125: # K2ROLL INDICATOR FOR ROLL SWITCH
037255,000126:
037256,000127: # LAD MAX L/D (MIN ACTUAL VEHICLE L/D) 1
037257,000128:
037258,000129: # LADPAD NOMINAL VEHICLE L/D, SP PAD LOAD 1 (NOM = 0.3)
037259,000130:
037260,000131: # LATANG LATERAL RANGE 4 RADIANS
037261,000132:
037262,000133: # LEQ EXCESS C.F. OVER GRAV=(VSQ-1)GS 128.8 FPSS
037263,000134:
037264,000135: # LEWD UPCONTROL REFERENCE L/D 1
037265,000136:
037266,000137: # LOD FINAL PHASE L/D 1 (NOM = 0.18)
037267,000138:
037268,000139: # LODPAD FINAL PHASE L/D, SP PAD LOAD 1
037269,000140:
037270,000141: # L/D DESIRED LIFT TO DRAG RATIO 1
037271,000142: # (VERTICAL PLANE)
037272,000143: #
037273,000144: # L/D1 TEMP STORAGE FOR L/D IN LATERAL 1
037274,000145:
037275,000146: # L/DCMINR LAD COS(15DEG) 1 (NOM = 0.2895)
037276,000147:
037277,000148: # PREDANGLE PREDICTED RANGE (FINAL PHASE) 2700 NM = PREDANG
037278,000149:
037279,000150: # Q2 FINAL PHASE RANGE -23500 Q3 21600 NM
037280,000151: # Q2 = FCN(LAD)
037281,000152:
037282,000153: # Q7 MINIMUM DRAG FOR UPCONTROL 805FPSS
037283,000154:
037284,000155: # RDOT ALTITUDE RATE 2 VSAT
037285,000156:
037286,000157: # RDOTREF REFERENCE RDOT FOR UPCONTROL 2 VSAT
037287,000158:
037288,000159: # RDTR REFERENCE RDOT FOR DOWNCONT 2 VSAT NOT SAVED
037289,000160:
037290,000161: # ROLLC ROLL COMMAND 1 REVOLUTION
037291,000162:
037292,000163: # RTOGO RANGE TO GO (FINAL PHASE) 2700 NM = FX +2
037293,000164:
037294,000165: # SL SINE OF LATITUDE 1 NOT SAVED
037295,000166:
037296,000167: # T TIME B 28 CENTISEC = TIME2,TIME1
037297,000168:
037298,000169: # THETA DESIRED RANGE (RADIANS) 2 PI RADIANS = THETAH
037299,000170:
037300,000171: # THETNM DESIRED RANGE (NM) 21600 NM NON EXISTENT
037301,000172:
037302,000173: # V VELOCITY MAGNITUDE 2 VSAT
037303,000174: #
037304,000175: # V1 INITIAL VELOCITY FOR UPCONTROL 2 VSAT
037305,000176:
037306,000177: # VL EXIT VELOCITY FOR UPCONTROL 2 VSAT
037307,000178:
037308,000179: # VREF REFERENCE VELOCITY FOR UPCONTROL 2 VSAT
037309,000180:
037310,000181: # VS1 VSAT OR V1, WHICHEVER IS SMALLER 2 VSAT
037311,000182: # 2 2
037312,000183: # VBARS VL /VSAT 4
037313,000184: # 2 2
037314,000185: # VSQ NORMALIZED VEL. SQUARED = V /VSAT 4 = VSQUARE
037315,000186:
037316,000187: # WT EARTH RATE TIMES TIME 1 REVOLUTION NOT SAVED
037317,000188:
037318,000189: # X INTERMEDIATE VARIABLE IN G-LIMITER 2 VSAT NOT SAVED
037319,000190:
037320,000191: # Y LATERAL MISS LIMIT 4 RADIANS NOT SAVED
037321,000192:
037322,000193: # Page 840
037323,000194: # EXTRA COMPUTER ERASABLE LOCATIONS NOT SHOWN ON FLOW CHARTS
037324,000195: # ----------------------------------------------------------
037325,000196:
037326,000197: # VARIABLE DESCRIPTION MAXIMUM VALUE
037327,000198: # -------- ----------- -------------
037328,000199:
037329,000200: # GOTOADDR ADDRESS SELECTED BY SEQUENCER
037330,000201:
037331,000202: # XPIPBUF BUFFER TO STORE X PIPA COUNTS
037332,000203:
037333,000204: # YPIPBUF BUFFER TO STORE Y PIPA COUNTS
037334,000205:
037335,000206: # ZPIPBUF BUFFER TO STORE Z PIPA COUNTS
037336,000207:
037337,000208: # PIPCTR COUNTS PASSES THRU PIPA READ ROUTINE
037338,000209:
037339,000210: # JJ INDEX IN FINAL PHASE TABLE LOOK-UP
037340,000211:
037341,000212: # MM INDEX IN FINAL PHASE TABLE LOOK-U
037342,000213:
037343,000214: # GRAD INTERPOLATION FACTOR IN FINAL PHASE
037344,000215:
037345,000216: # FX DRANGE/D L/D = F3 2700 NM
037346,000217:
037347,000218: # FX +1 AREF 805 FPSS
037348,000219:
037349,000220: # FX +2 RTOGO 2700 NM
037350,000221:
037351,000222: # FX +3 RDOTREF VSAT/4
037352,000223:
037353,000224: # FX +4 DRANGE/D RDOT = F2 21600/2VS NM/FPS
037354,000225:
037355,000226: # FX +5 DRANGE/D DRAG = F1 2700/805 NM/FPSS
037356,000227:
037357,000228: # TEM1B TEMPORARY LOCATION
037358,000229:
037359,000230: # TIME/RTO TIME OF INITIAL TARGET RTINIT B 28 CENTISEC
037360,000231:
037361,000232: # DTEAROT EST TIME BETWEEN RTINIT AND RT B 28 CENTISEC
037362,000233: # _
037363,000234: # UNITV UNIT V VECTOR 2
037364,000235: # _
037365,000236: # UNITR UNIT R VECTOR 2
037366,000237: # _
037367,000238: # -VREL NEGATIVE VELOCITY REL TO ATMOSP 2 VSAT
037368,000239:
037369,000240: # COMPUTER SWITCHES INITIAL STATE CM/FLAGS = STATE +6
037370,000241: # ----------------- ------------- -------------------
037371,000242:
037372,000243: # ENTRYDSP DO ENTRY DISPLAY, IF SET NON-BRANCH (1) 92D, BIT 13
037373,000244: # GONEPAST INDICATES OVERSHOOT OF TARGET NON-BRANCH (0) 95D, BIT 10
037374,000245: # RELVELSW RELATIVE VELOCITY SWITCH NON-BRANCH (0) 96D, BIT 9
037375,000246: # EGSW FINAL PHASE SWITCH NON-BRANCH (0) 97D, BIT 8
037376,000247: # FIRSTPAS INITIAL PASS THRU HUNTEST NON-BRANCH (0) 98D, BIT 7
037377,000248: # HIND INDICATES ITERATION IN HUNTEST NON-BRANCH (0) 99D, BIT 6
037378,000249: # INRLSW INDICATES INIT ROLL ATTITUDE SET NON-BRANCH (0) 100D, BIT 5
037379,000250: # LATSW INHIBIT DOWNLIFT SWITCH IF NOT SET BRANCH (1) 101D, BIT 4
037380,000251: # .05GSW INDICATES DRAG EXCEEDS .05 GS BRANCH (0) 102D, BIT 3
037381,000252:
037382,000253: # GONEBY INDICATES GONE PAST TARGET (SET) SELF-INITIALIZING 112D, BIT 8
037383,000254:
037384,000255: # Page 841
037385,000256: # CONSTANTS AND GAINS VALUE
037386,000257: # ------------------- -----
037387,000258:
037388,000259: # C1 FACTOR IN ALP COMPUTATION 1.25
037389,000260: # C16 CONSTD GAIN ON DRAG .01
037390,000261: # C17 CONSTD GAIN ON RDOT .001
037391,000262: # C18 BIAS VEL. FOR FINAL PHASE START 500 FPS
037392,000263: # C20 MAX DRAG FOR DOWN-LIFT 175 FPSS
037393,000264: # CHOOK FACTOR IN AHOOK COMPUTATION .25
037394,000265: # CH1 FACTOR IN GAMMAL COMPUTATION 1.0
037395,000266: # COS15 COS( 15 DEG ) .965
037396,000267: # DLEWD0 INITIAL VARIATION IN LEWD -.05
037397,000268: # D2 DRAG TO CHANGE LEWD 175 FPSS
037398,000269: # DT COMPUTATION CYCLE TIME INTERVAL 2 SEC.
037399,000270: # GMAX MAXIMUM ACCELERATION 257.6 FPSS (8 G'S)
037400,000271: # KA1 FACTOR IN KA CALC 1.3 GS
037401,000272: # KA2 FACTOR IN KA CALC .2 GS
037402,000273: # KA3 FACTOR IN D0 CALC 90 FPSS
037403,000274: # KA4 FACTOR IN D0 CALC 40 FPSS
037404,000275: # KB1 OPTIMIZED UPCONTROL GAIN 3.4
037405,000276: # KB2 OPTIMIZED UPCONTROL GAIN .0034
037406,000277: # KDMIN INCREMENT ON Q7 TO DETECT END OF KEPLER PHASE .5 FPSS
037407,000278: # KTETA TIME OF FLIGHT CONSTANT 1000
037408,000279: # KLAT1 FACTOR IN KLAT CALC 1/24
037409,000280: # K44 GAIN USED IN INITIAL ROLL SECTION 19749550 FPS
037410,000281: # LATBIAS LATERAL SWITCH BIAS TERM .41252961 NM
037411,000282: # LEWD1 NOMINAL UPCONTROL L/D .15
037412,000283: # POINT1 FACTOR TO REDUCE UPCONTROL GAIN .1
037413,000284: # Q2 FINAL PHASE RANGE - 23500 Q3 -1002 NM
037414,000285: # Q3 FINAL PHASE DRANGE/D V .07 NM/FPS
037415,000286: # Q5 FINAL PHASE DRANGE/D GAMMA 7050 NM/RAD
037416,000287: # Q6 FINAL PHASE INITIAL FLIGHT PATH ANGLE .0349 RAD
037417,000288: # Q7F MIN DRAG FOR UPCONTROL 6 FPSS
037418,000289: # Q7MIN IN VALUE FOR Q7 IN FACTOR CALCULATION 40 FPSS
037419,000290: # Q19 FACTOR IN GAMMAL1 CALCULATION .5
037420,000291: # Q21 FACTOR IN Q2 CALCULATION 1000 NM
037421,000292: # Q22 FACTOR IN Q2 CALCULATION -1302 NM
037422,000293: # VFINAL1 VELOCITY TO START FINAL PHASE ON INITIAL ENTRY 27000 FPS
037423,000294: # VFINAL FACTOR IN INITIAL UP-DOWN CALC 26600 FPS
037424,000295: # VLMIN MINIMUM VL 18000 FPS
037425,000296: # VMIN VELOCITY TO SWITCH TO RELATIVE VEL VSAT/2
037426,000297: # VRCONTRL RDOT TO START INTO HUNTEST 700 FPS
037427,000298: # VRCONT=COMPUTER NAME
037428,000299: # 25NM TOLERANCE TO STOP RANGE ITERATION 25 NM
037429,000300: # VQUIT VELOCITY TO STOP STEERING 1000 FPS
037430,000301:
037431,000302: # Page 842
037432,000303: # CONVERSION FACTORS AND SCALING CONSTANTS
037433,000304: # ----------------------------------------
037434,000305:
037435,000306: # ATK ANGLE IN RAD TO NM 3437.7468 NM/RAD
037436,000307: # G5 NOMINAL G VALUE FOR SCALING 32.2 FPSS
037437,000308: # H5 ATMOSPHERE SCALE HEIGHT 28500 FT
037438,000309: # J GRAVITY HARMONIC COEFFICIENT .00162346
037439,000310: # KWE EQUATORIAL EARTH RATE 1546.10168 FPS
037440,000311: # MUE EARTH GRAVITATIONAL CONSTANT 3.986032233 E14 CUBIC M/ SEC SEC
037441,000312: # RE EARTH RADIUS 21202900 FT
037442,000313: # REQ EARTH EQUATORIAL RADIUS 20925738.2 FT
037443,000314: # VSAT SATELLITE VELOCITY AT RE 25766.1973 FPS
037444,000315: # WIE EARTH RATE .0000729211505 RAD/SEC
037445,000316:
037446,000317: # (END GSOP AS-278, VOL 1, FIG. 5.6-3 CONSTANTS, GAINS, ETC.)
037447,000318:
037448,000319: # DISPLAY QUANTITIES
037449,000320: # ------------------
037450,000321:
037451,000322: # (SEE SECTION 4 OF THE GSOP FOR SIGN CONVENTIONS.)
037452,000323:
037453,000324: # VARIABLE DESCRIPTION MAXIMUM VALUE
037454,000325: # -------- ----------- -------------
037455,000326:
037456,000327: # QMAX PREDICTED MAXIMUM ENTRY ACCEL 163.84 GS N 60
037457,000328: # VPRED PREDICTED VELOCITY AT ALTITUDE 128 M/CENTISEC N 60
037458,000329: # 400K FT ABOVE FISCHER RADIUS.
037459,000330: # GAMMAEI PREDICTED GAMMA AT ALTITUDE 1 REVOLUTION N 60
037460,000331: # 400K FT ABOVE FISCHER RADIUS
037461,000332: # D DRAG ACCELERATION 805 FPSS N 64
037462,000333: # VMAGI INERTIAL VELOCITY MAGNITUDE 128 M/CENTISEC N 64, N 68
037463,000334: # THETAH DESIRED RANGE ANGLE NM 1 REVOLUTION N 64, N 67
037464,000335: # LAT PRESENT LATITUDE 1 REVOLUTION N 67
037465,000336: # LONG PRESENT LONGITUDE 1 REVOLUTION N 67
037466,000337: # RTOGO RANGE ANGLE TO SPLASH FROM 1 REVOLUTION N 67
037467,000338: # EMSALT FT ABOVE FISCHER RADIUS (IN NM)
037468,000339: # VIO PREDICTED VELOCITY AT ALTITUDE 128 M/CENTISEC N 63
037469,000340: # EMSALT FT ABOVE FISCHER RADIUS.
037470,000341: # TTE TIME OF FREE FALL TO ALT B 28 CENTISEC N 63
037471,000342: # EMSALT FT ABOVE FISCHER RADIUS
037472,000343: # ROLLC ROLL COMMAND 1 REVOLUTION N 68, N 68, N 69
037473,000344: # LATANG CROSS-RANGE ERROR (XRNGERR) 4 RADIANS N 66
037474,000345: # DNRNGERR DOWN RANGE ERROR 1 REVOLUTION N 66
037475,000346: # (PREDANG - THETAH IN NM)
037476,000347: # HDOT ALTITUDE RATE 128 M/CENTISEC N 68
037477,000348: # QT MINIMUM DRAG FOR UPCONTROL 805 FPSS N 69
037478,000349: # VL EXIT VELOCITY FOR UP-CONTROL 2 VSAT N 69
037479,000350:
037480,000351: # Page 843
037481,000352: # BODY ATTITUDE QUANTITIES (CM/POSE)
037482,000353: # ----------------------------------
037483,000354:
037484,000355: # VARIABLE DECRIPTION MAXIMUM VALUE
037485,000356: # -------- ---------- -------------
037486,000357: # _
037487,000358: # -VREL NEGATIVE VELOCITY REL TO ATMOS. 2 VSAT
037488,000359: # _
037489,000360: # OLDUYA USED FOR UYA BELOW 1000 FPS 2
037490,000361: # _
037491,000362: # UXA/2 UNIT VECTOR TRIAD 2
037492,000363: # _
037493,000364: # UYA/2 BASED ON 2
037494,000365: # _
037495,000366: # UZA/2 THE TRAJECTORY 2
037496,000367: # _
037497,000368: # UBX/2 UNIT VECTOR 2
037498,000369: # _
037499,000370: # UBY/2 BODY TRIAD 2
037500,000371: # _
037501,000372: # UBZ/2 FOR CM. 2
037502,000373:
End of include-file ENTRY_LEXICON.agc. Parent file is MAIN.agc