Category : Science and Education
Archive : SATFLY11.ZIP
Filename : SATFLY11.BAS
Output of file : SATFLY11.BAS contained in archive : SATFLY11.ZIP
*** SATFLY11.BAS, April 15, 1989 W J Cuneo, Jr (301) 977 5778
*** SATFLY11.DOC is the companion document file read by this program. å
*** Copyright 1989. Commercial use not authorized without agreement beforehand. ó
( § ^ û
2 É Ý < ¯ AêH,OêY:¬ Z: B,IêK ] F CLIFE(, ): *** Holds the empirical factors for life estimating ê P DS( ,),DH( ,),DL( ,):*** for the altitude/density input values for calculating the semilog fit for the selected atmosphere. Z DENCOEFF( ,): *** will hold the semilog coefficients which will be used to calculate density as function of altitude. Density=10^(ah+b) ´ d ALTITUDE/DENSITY DATA FOR STANDARD ATMOSPHERE. ù n 0,1.22:*** units are altitude (km), density (Kg/meters cubed)
x 100,5.6E-7
150,2.1E-9 -
200,2.5E-10 ?
300,1.9E-11 Q
400,2.8E-12 c
ª 500,5.2E-13 v
´ 600,1.14E-13
¾ 700,3.1E-14
È 800,1.14E-14
Ò 900,5.8E-15 À
Ü 1000,3.6E-15 æ DATA FOR ALTITUDE/DENSITY FOR HIGH SOLAR ACTIVITY ATMOSPHERE Hð 0,1.22:*** units are altitude (km), density (Kg/meters cubed) Yú 100,5.6E-7 j 150,3.2E-9 | 200,4.5E-10 300,5.0E-11 " 400,2.0E-11 ², 500,5.2E-12 Ä6 600,1.4E-12 Ö@ 700,6.0E-13 èJ 800,3.0E-13 úT 900,1.0E-13
^ 1000,5.0E-14 Lh ALTITUDE/DENSITY DATA FOR LOW SOLAR ACTIVITY ATMOSPHERE. r 0,1.22:*** units are altitude (km), density (Kg/meters cubed) ¢| 100,5.6E-7 ³ 150,2.1E-9 Å 200,1.5E-10 × 300,9.0e-12 é¤ 400,3.0E-13 û® 500,3.0E-14
¸ 600,5.0E-15 Â 700,1.0E-15 1Ì 800,1.5E-16 CÖ 900,8.0E-17 Và 1000,5.0E-17 ê EMPIRICAL FACTORS FOR LIFE ESTIMATING ¶ô .2,.2,.2,.2,.37,.38,.355,.33,.314,.32,.36,.43 íþ .2,.2,.2,.2,.414,.5,.565,.432,.395,.435,.38,.355 ' .2,.2,.2,.2,.275,.298,.235,.255,.264,.236,.286,.392 H___________________________ q BEGINNING OF EXECUTABLE STATEMENTS &À:Ê ,#:" WAIT FOR 4 SECONDS.... " é0 DEFINE CONSTANTS USED. THE `LET' IS UNNECESSARY, BUT DISTINCTIVE. /: Cçìÿ(
): *** constant for converting natural log to base 10 BD PIç ¾h!¢ÚI N Gç ì_:*** Gravitational Constant in mks (nt-m2/kg2) «X MEARTHç d^ Ó:*** Mass of earth in Kg îb UçGëMEARTH: *** U simplifies the satellite motion equations ,l METPERNMç Àë ë \"ìd: *** meters per nautical mile rv REARTHç së ë ë \"ìd: *** earth radius (6364.956 meters) NTLBç ¨W: *** newtons per pound 8 OPTIMEç 3"{:*** empirical value to adapt realtime to simulation time for display of time speedup/slowdown. Value is code, not machine, dependent. ICALCç
:*** number of calculation cycles done before display update Í À: *** to routine which estimates speed of machine; needs clock ¨ LOAD ALTITUDE/DENSITY DATA FOR STANDARD ATMOSPHERE. ² Iç Ì $¼ Jç Ì 2Æ DS(I,J) :Ð J BÚ I ä LOAD DATA FOR ALTITUDE/DENSITY FOR HIGH SOLAR ACTIVITY ATMOSPHERE î Iç Ì §ø Jç Ì µ DH(I,J) ½ J Å I LOAD ALTITUDE/DENSITY DATA FOR LOW SOLAR ACTIVITY ATMOSPHERE. * Iç Ì &4 Jç Ì 4> DL(I,J) <H J DR I u\ LOAD EMPIRICAL FACTORS FOR LIFE ESTIMATING f Jç Ì p Kç Ì £z CLIFE(J,K) CCLIFE(J,K)çCLIFE(J,K)ì ö(< :*** this fudge factor is artifact of earlier process to calibrate actual vs predicted. Am too lazy to change the numbers. K K S J t¢___________________________ ¶¬ BEGINNING OF PROGRAM CYCLE FOR A PARTICULAR SATELLITE CASE. ¶ ISOUNDç:***flag for using/not using sound; initially off;`o' toggles :À DDTç:*** used for final seconds clock display. Ê ISCREENç:*** assures screen selection will reset at start of a case. ÃÔTIMEç:ORBITç:Iç:*** start cumulating variables over øÞFç:FHOLDç:*** zeros the rate of decay measure è___________________________ Cò*** NOW DISPLAY THE SELECTION SCREEN {ü¿ ,:À: ¿ ,:Ê ,:"SATFLY11.BAS Apr 15, 1989" ¾¿ ,:Ê ,:" HOW LONG WILL A SATELLITE REMAIN IN ORBIT ? " Ê ,:" THIS PROGRAM CALCULATES THE DRAG DECAY OF A CIRCULAR ORBIT " 6Ê ,:" HIT `d' TO USE DEFAULT VALUES: " j$Ê ,':" 150 nautical miles initial altitude " .Ê
,':" 500 kilograms mass " Ô8Ê ,':" 2 square meters cross section " BÊ ,':" 1000 seconds per step in time " >LÊ
,':" standard atmosphere density model " oVÊ ,:" HIT
Í R : *** to new value selection routine. 3 ° ÿ(Z2$)ç
Í :*** new values selected, so exit to next stage. n º ÿ(Z2$)çd Í
: *** to definition of defaults. µ Ä ÿ(Z2$)çd Í :*** use default values, so exit to next stage. ê Î ÿ(Z2$)çr Í Ð : *** to text description. % Ø ÿ(Z2$)çr Í : *** to beginning after reading text Y â ÿ(Z2$)ç Í À:*** prepare for quit routine. ì ÿ(Z2$)ç Í P :¡ : *** to final quit routine. · ö___________________________ æ NOW CREATE SELECTION DEPENDENT CONSTANTS
l: *** to make standard altitude graphic bar P DEFINE A STRING ONCE FOR USE MANY TIMES LATER } BATMç Í ZATMOS$ç"standard atmosphere" ª ( BATMç Í ZATMOS$ç"high solar activity" Ö 2 BATMç Í ZATMOS$ç"low solar activity" 8 < BATM ,Ò,:*** Calculate semilog fit coefficients for selected atmosphere u F¿ ,:À:¿ ,: : *** put options on status screen ° P KMç Í 2
: *** display initial values, nm units. ë Z KMç Í Z
: *** display initial values, km units. (!d ALTçALTITUDEëMETPERNM: *** initial altitude in meters t!n RçREARTHéALT:*** distance of satellite from center of earth (meters) ½!x NOW CALCULATE TWO VALUES NEEDED TO INITIALIZE THE CALCULATION LOOP õ! Vç(UìR)í :*** initial velocity of satellite 8" Eçê(MëU)ì(ëR) :*** initial energy of the satellite's orbit Y"___________________________ " NOW START THE LOOP FOR ORBIT DECAY CALCULATION INCREMENTS ã"ª Iç Ì ICALC: *** do ICALC calculation cycles before each display. k#´ZT$çÞ: *** toggle indicator; if anything is found in inkey, then `s',`f',`o', `p' or `esc'is looked for in the GOSUB below. Ú#¾ ÿ(ZT$)æ Í ¸ : *** to toggle DT up, down by x2; toggle sound on/off; pause; or to quit $ÈTHETA1ç(VìR)ëDT :*** calculation of orbital epoch increment h$ÒHç(RêREARTH)ì è:*** density equations are in km; use H as the variable ¸$Ü Ê ,: Hæç ° Í " NOTE - Altitudes over 1200 Km are not modelled well. " 6%æLç: *** Find altitude band where satellite is now. Need for selection of density model semilog coefficients. J%ð Hæç Í Lç Z%ú Læ Í Â n% Hæç Í Lç ~% Læ Í Â % Hæç ¼ Í Lç
¢%" Læ Í Â µ%, Hæç X Í Lç Å%6 Læ Í Â Ø%@ Hæç ô Í Lç è%J Læ Í Â û%T Hæç Í Lç &^ Læ Í Â &h Hæç , Í Lç .&r Læ Í Â @&| HæçÈ Í Lç P& Læ Í Â b& Hæç Í Lç r& Læ Í Â &¤ Hæçd Í Lç &® Læ Í Â ¥&¸ Hæç Í Lç ñ&ÂDENSITYç
í(DENCOEFF(L,)ëHéDENCOEFF(L,)): *** calculate density at H 4'ÌDEçDENSITYëNXë(Ví)ëDT : *** orbital energy change in time dT b'ÖENEWçEêDE : *** new energy after time dT ©'àRNEWçê(MëU)ì(ëENEW) : *** new radius corresponding to new energy î'ê RNEWçèREARTH Í ô :¡ þ:*** possibly start altitude too low 0(ô TIMEç Í @:*** if true, then start altitude IS too low j(þVNEWç(UìRNEW)í : *** new velocity at new radius ±(THETA2ç(VNEWìRNEW)ëDT :*** calculation of orbital epoch increment I)ORBITçORBITé(THETA1éTHETA2)ì(ëëPI):*** orbit epoch averaged using beginning and end velocities and radii for the latest time increment. u) PERIODç(ëDTëëPI)ì((THETA1éTHETA2)ë<) º)&TIMEçTIMEéDT:*** keep current time into the flight (in seconds) ü)0 ISOUNDç Í
:*** make reentry warning sound if desired \*:Fç(ëPIì(THETA1))ë(RêRNEW)ì(RêREARTH): *** fractional change in orbital altitude per orbit ¨*DFORCEçDENSITYëNXëVí : *** drag force in newtons at start of increment ê*N RNEWèREARTHé N Í È
: *** to burnup routine, below 20km 6+X Fæ Í DDTçDDTéDT: *** make value for final seconds clock display Î+bRHOLDçR:RNEWHOLDçRNEW:VHOLDçV:DENHOLDçDENSITY:THETA1HDçTHETA1:*** holds current values for output after new values are evaluated as a burnup. ,lTHETA2HDçTHETA2:PERIODHDçPERIOD:ORBITHDçORBIT:TIMEHOLDçTIME:FHOLDçF: FORCEHLDçFORCE:*** holds current values for output after new values are evaluated as a burnup. Ð,vEçENEW:RçRNEW:VçVNEW: *** set new initial values for next iteration Ø, I - ISOUNDç Í Ä p,:*** a little pip for each display Ë- ISCREENç Í î: allows only one pass through the ISCREEN selection, thus preserving the initial value calculated in the GOSUB for PREDICTed number of days. . Fæ Í ISCREENç: *** when near reentry go to fine time screen <.¨ :*** to make standard display ¹.² ISCREEN î , ,¬
,: to appropriate screen for life dependent presentation of status of satellite. ý.¼ : *** Repeat loop. This loop is the core of this program. /Æ /Ð------ 3/Ú FOLLOWING ARE THE SUBROUTINES ?/ä------ /î ROUTINE TO SELECT DISPLAY SCREEN APPROPRIATE TO PREDICTED LIFETIME k0øDAYENTERç((ìFHOLD)ëPERIODHD)ëCLIFE(BATM,L)ì(<ë):PREDICTçDAYENTER: *** first PREDICTion of time (days) to entry; this value made in very first increment of time, and kept for display at burnup or quit. ±0 DAYENTER æç ' Í ISCREENç:*** ISCREEN selects display format Ç0 ISCREENæ Í > æ0 DAYENTER æç Í ISCREENç ü0 ISCREENæ Í > 1* DAYENTER æç Í ISCREENç 114 ISCREENæ Í > 71> C1H------ n1R---NEW INITIAL VALUE SELECTION SCREEN 1\¿ ,:À:¿ , à1fÊ ,: "Now enter initial altitude, mass, cross-section, time increment, and atmosphere" (2p:"Please input initial altitude. You will select km or nm next. " X2z " ALTITUDE (Default is 150) = ",ALTITUDE w2 ALTITUDEç Í ALTITUDEç °2"Hit `k' if kilometers, hit `n' if nautical miles"; í2 z:*** to routine to purge inkey of stray keystrokes
3¢Z1$çÞ: ÿ(Z1$)ç Í ¢ 83¬ ÿ(Z1$)çk Í " *KILOMETERS selected" X3¶ ÿ(Z1$)çk Í KMç :¡ KMç 3À ÿ(Z1$)çk Í Þ: *** exit decision routine for units Æ3Ê ÿ(Z1$)çn Í " *NAUTICAL MILES selected" ä3Ô ÿ(Z1$)çn Í Þ :¡ ¢ j4Þ KMç Í ALTITUDEçALTITUDEë èìMETPERNM: *** keep the variable ALTITUDE in nautical mile units throughout this program. °4è ALTITUDEè Í :*** to announce altitude is too low to start ø4ò ALTITUDEæ è Í Â:*** to announce altitude is too high to start /5ü:"Please input mass (kg.). Default is 500 kg. ": P5 "MASS = "; M: Mç Í Mç ô m5 Mè Í ZERROR$ç" MASS " ¥5 Mè Í þ: *** to announce an illogical value. ê5$ :"Please input cross-section (meters squared). Default is 2.": A6. "(Change cross-section proportionally if drag coefficient is different than 2.)" l68 "CROSS SECTION = "; NX: NXç Í NXç 6B NXè Í ZERROR$ç" CROSS SECTION " Ì6L NXè Í þ: *** to announce an illogical value. 7V :"Please input time step length (seconds). Default is 1000 seconds.": A7` "TIME STEP = "; DT: DTç Í DTç è i7j DTè Í ZERROR$ç" TIME INCREMENT " ¢7t DTè Í þ: *** to announce an illogical value. ú7~ :"Select atmosphere. S = standard, H = hi solar activity, L = low solar activity" "8 "Default is standard atmosphere"; -8 BATMç \8 z:*** purge inkey of stray keystrokes v8¦ Z$çÞ: ÿ(Z$)ç Í ¦ ¸8° ÿ(Z$)ç
Í ì : *** short goto for a bypass to speed up â8º ÿ(Z$)çs Í BATMç : s is selected 9Ä ÿ(Z$)çh Í BATMç : h is selected 69Î ÿ(Z$)çl Í BATMç : l is selected u9Ø BATMç Í ¦ : *** continue to wait for a correct choice ¶9â ö : *** this short goto enables the bypass 8 lines above :ì BATMç: *** selects standard atmosphere if default bypass used above :ö :
------ ?:
---DEFINITION OF DEFAULT INITIAL VALUES m:
ALTITUDEç:Mç ô:NXç:DTç è:KMç:BATMç s:
:(
------ ª:2
---DISPLAY INITIAL VALUES, NM UNITS. ;<
¿ ,:Ê ,:"Start(nm)=";ALTITUDE;" Mass(Kg)=";M;" Xsection(m2)=";NX;" ";ZATMOS$:¿ , ;F
;P
------ F;Z
---DISPLAY INITIAL VALUES, KM UNITS. ²;d
¿ ,:Ê ,:"Start(km)=";ALTITUDEëMETPERNMì è;" Mass(Kg)=";M;" Xsection(m2)=";NX;" ";ZATMOS$:¿ , ¸;n
Ä;x
------ ð;
--- ROUTINE FOR REENTRY WARNING SOUNDS (<
Fè Í :*** not near reentry; sound no alarm o<
Fæ è Í ´
: *** use constant frequency sound; reentry imminent ³<
TONEçFëé%:*** tone <37 makes GWBASIC fail, but BASICA works. Ü<ª
Ä TONE,:: *** reentry alert sound =´
Ä ,::*** reentry is imminent. =¾
------ -=È
--- ROUTINE FOR REENTRY G=Ò
ISOUNDç Í Ä Ü, ~=Ü
IBç Ì IPATCH:*** dapples screen with hot spots ¤=æ
IROWçÿ (ÿë)é:ICOLçÿ (ÿëN)é Ë=ð
Ê IROW,ICOL:¿ ,: ÿ(²);ÿ(²) Ô=ú
IB > ¿ ,:Ê ,:ZSPACE$çÿ(<): ZSPACE$;:*** erases line G> ISOUNDç Í " :*** bypass sound if not desired > Ä ,:¿ , :À:Ä ,:¿ ,:À:Ä 2,:À:Ä (,:¿
,
:À:Ä &,:¿ ,:À:¿ , ç>" Iç Ì IFLICKER:*** repeat soundless colors for good persistence ?, ¿ , :À:¿ ,:À:¿
,
:À:¿ ,:À:¿ , ?6 I `?@ : *** to display last calculated state before reentry r?J Ê ,: ZBAR$ ?T Ê ,NBAR: ÿ(²) ì?^ ¿ ,:Ê ,:" REENTRY !! LAST CALCULATED STATE BEFORE REENTRY IS SHOWN ABOVE. " 2@h IBç Ì IFLASH:*** makes flashing burnup cloud on altitude bar. \@r Ê ,NBAR: ÿ(±):Ê ,NBARê: ÿ(²) @| Ê ,NBAR: ÿ(ù):Ê ,NBARê: ÿ(*) °@ Ê ,NBAR: ÿ(²):Ê ,NBARê: ÿ(±) ¹@ IB ú@ P:*** to routine for choice of new case or exit to DOS. :A¤ : *** return ineffective; only way out is new case or DOS FA® ------ A¸ --- ROUTINE TO TOGGLE SECONDS PER STEP UP/DOWN BY x2, OR TO QUIT/PAUSE ÉAÂ ÿ(ZT$)çf Í DTçDTë: *** `f' (faster) detected BÌ ÿ(ZT$)çs Í DTçDTì: *** `s' (slower) detected ABÖ ÿ(ZT$)ço Í :: *** `o' detected; toggle sound on/off Bà ÿ(ZT$)çp Í ð: *** to pause routine for status screen ÄBê ÿ(ZT$)ç Í È: *** to quit routine for status screen ÊBô ÖBþ ------ C --- ROUTINE TO MAKE STANDARD DISPLAY C Ê ,:" CURRENT ALTITUDE (nm, km) = ";: ×"####,.#######"; (RHOLDêREARTH)ìMETPERNM;: ×"#######,.#######";(RHOLDêREARTH)ì è C Ê ,: ZBAR$ ÌC& NBARçéÿ (((RHOLDêREARTH)ìMETPERNM)ëFìALTITUDE) D0 Ê ,NBAR: ÿ():*** prints satellite symbol on altitude bar D: Ê ,:" ATMOSPHERE DENSITY (Kg/m3) = ";: ×"##.######^^^^"; DENHOLD;:" ( 1.22 Kg/m3 at sea level ) " êDD Ê ,:" DRAG FORCE (newtons, lbs) = ";: ×"##.##^^^^";FORCEHLD;:" ";: ×"##.##^^^^";FORCEHLDì ¨W EN Fæ Âu{ Í (:*** display g force EX Ê
,:" VELOCITY (feet/s, meters/s) = ";: ×"#####,.#####";VHOLDë áz ì ;: ×"#######,.#####";VHOLD ìEb Ê ,: " ORBITAL PERIOD (minutes) = ";: ×"###.######";(ëDTëëPI)ì((THETA1HDéTHETA2HD)ë<);:" " CFl DAYENTERç((ìFHOLD)ëPERIODHD)ëCLIFE(BATM,L)ì(<ë):*** estimate of days to entry kFv DAYTOTALçDAYENTERéTIMEHOLDì( ë) qF }F ------ ÀF --- ROUTINE TO OUTPUT STATUS SCREEN FOR 10,000 > LIFE > 1 DAY LG Ê ,:" FRACTIONAL ALTITUDE CHANGE PER ORBIT = ";: ×"##.####^^^^";FHOLD;:" (";: ×"##.###^^^^";(RHOLDêREARTH)ëFHOLD;:" meters ) " G¨ Ê ,.:" ORBITS FLOWN = ";: ×"#####,.###";ORBITHD H² Ê ,:" TIME (days/hours/sec) =";: ×"#####,.###";TIMEHOLDì( ë);:" ";: ×"######,.###";TIMEHOLDì ;:" ";: ×"##.####^^^^";TIMEHOLD ¶H¼ Ê ,:" DAYS TO ENTRY ";: ×"#######,.##";DAYENTER;:" ";: ×"####.##";dëDAYENTERìDAYTOTAL;:" % ";:" DAYS TOTAL LIFETIME ";: ×"#####,.##";DAYTOTAL IÆ Ê ,: " TIME STEP (sec) = ";: ×"#########,.##";DT;: " (`s' to slow, `f' to speedup x2 )" dIÐ :*** to calculate/display relation of real to simulated time. jIÚ vIä ------ ¶Iî --- ROUTINE TO OUTPUT STATUS SCREEN FOR LIFE > 10,000 DAYS CJø Ê ,:" FRACTIONAL ALTITUDE CHANGE PER ORBIT = ";: ×"##.####^^^^";FHOLD;:" (";: ×"##.####^^^^";(RHOLDêREARTH)ëFHOLD;:" meters ) " |J
TIMEæ |.« Í *
:*** use exponent display of time ºJ
Ê ,.:" ORBITS FLOWN = ";: ×"###########,.#";ORBITHD XK
Ê ,:" TIME (years/days/sec) =";: ×"#######,.##";TIMEHOLDì( ëë 6);:" ";: ×"##########,";TIMEHOLDì( ë);:" ";: ×"##.####^^^^";TIMEHOLD K
>
:*** bypass exponent display of time ÎK*
Ê ,.:" ORBITS FLOWN = ";: ×"##.####^^^^";ORBITHD;:" " TL4
Ê ,:" TIME (years/sec) = ";: ×"##.###^^^^";TIMEHOLDì( ëë 6);:" ";: ×"##.####^^^^";TIMEHOLD;:" " L>
DAYTOTALæ < Í \
:*** jump to exponent display of life =MH
Ê ,:" YEARS TO ENTRY ";: ×"######,.##";DAYENTERì 6;:" ";: ×"####.##";dëDAYENTERìDAYTOTAL;:" % ";:" YEARS TOTAL LIFE ";: ×"######,.##";DAYTOTALì 6 lMR
f
:*** bypass exponent display of life N\
Ê ,:" YEARS TO ENTRY ";: ×"##.###^^^^";DAYENTERì 6;:" ";: ×"####.##";dëDAYENTERìDAYTOTAL;:" % ";:" YEARS TOTAL LIFE ";: ×"##.###^^^^";DAYTOTALì 6 PNf
DTæ Îl Í
:*** use exponent display of time step ·Np
Ê ,: " TIME STEP (sec) = ";: ×"###########,";DT;: " (`s' to slow, `f' to speedup x2 ) " ëNz
:*** bypass exponent display of time step `O
Ê ,: " TIME STEP (years) = ";: ×"##.###^^^^";DTì( ëë 6);: " (`s' to slow, `f' to speedup x2 ) " ¨O
:*** to calculate/display relation of real to simulated time. ®O
ºO¢
------ õO¬
--- ROUTINE TO OUTPUT STATUS SCREEN FOR LIFE < 1 DAY P¶
Ê ,:" FRACTIONAL ALTITUDE CHANGE PER ORBIT = ";: ×"##.####^^^^";FHOLD;:" (";: ×"##.##^^^^";(RHOLDêREARTH)ëFHOLD;:" meters ) " ºPÀ
Ê ,.:" ORBITS FLOWN = ";: ×"###,.#####";ORBITHD LQÊ
Ê ,:" TIME (days/hours/sec) =";: ×"##,.#####";TIMEHOLDì( ë);:" ";: ×"###,.######";TIMEHOLDì ;:" ";: ×"########.###";TIMEHOLD íQÔ
Ê ,:" DAYS TO ENTRY ";: ×"####,.######";DAYENTER;:" ";: ×"####.##";dëDAYENTERìDAYTOTAL;:" % ";:" DAYS TOTAL LIFETIME ";: ×"###,.######";DAYTOTAL SRÞ
Ê ,: " TIME STEP (sec) = ";: ×"#####,.###";DT;: " (`s' to slow, `f' to speedup x2 ) " Rè
:*** to calculate/display relation of real to simulated time. ¡Rò
Rü
------ øR--- ROUTINE TO OUTPUT STATUS SCREEN FOR NEAR REENTRY DISPLAYS OF TIME mSÊ ,:" ALTITUDE CHANGE PER SECOND = ";: ×"##.##^^^^";(RHOLDêRNEW)ìDT;:" meters " µS TIMEì( ë)æc Í B: *** bypass display tailored for <99 days ðS$ Ê ,.:" ORBITS FLOWN = ";: ×"####,.#####";ORBITHD T.Ê ,:" TIME (days/hours/sec) =";: ×"###.#####";TIMEHOLDì( ë);:" ";: ×"###.#####";TIMEHOLDì ;:" ";: ×"##.#####^^^^";TIMEHOLD ÄT8 V:*** bypass display of time tailored for life >99 days. UB Ê ,.:" ORBITS FLOWN = ";: ×"###.###^^^^";ORBITHD;:" " ULÊ ,:" TIME (days/hours/sec) =";: ×"##.###^^^^";TIMEHOLDì( ë);:" ";: ×"##,.###^^^^";TIMEHOLDì ;:" ";: ×"##.#####^^^^";TIMEHOLD ÛUVÊ ,: ×"######.####";DDT;:" final seconds clock " V`Ê ,:" SECONDS TO BURNUP ";: ×"####,.###"; DAYENTERëë ;:" ";: ×"####.###";dëDAYENTERìDAYTOTAL;:" % ";:" DAYS TOTAL LIFETIME";: ×"##.###^^^^";DAYTOTAL ìVjÊ ,: " TIME STEP (sec) = ";: ×"#####,.#####";DT;: " (`s' to slow, `f' to speedup x2 ) " 4Wt :*** to calculate/display relation of real to simulated time. :W~ FW------ W--- ROUTINE TO OUTPUT FINAL STATUS SCREEN UPON REENTRY OR QUIT ´W¿ ,: :*** to standard display êW¦Ê ,:ZSPACE$çÿ(F): ZSPACE$;:*** erases line _X°Ê ,:" ALTITUDE CHANGE PER SECOND = ";: ×"##.##^^^^";(RHOLDêRNEW)ìDT;:" meters " ¦Xº Ê ,.:" ORBITS FLOWN = ";: ×"##.##^^^^";ORBITHD;:" " AYÄÊ ,:" TIME (days/hours/sec) =";: ×"##.##^^^^";TIMEHOLDì( ë);:" ";: ×"##.##^^^^";TIMEHOLDì ;:" ";: ×"##.##^^^^";TIMEHOLD;:" " êYÎÊ ,:" DAYS TO REENTRY ";: ×"##.###^^^^";DAYENTER;:" ";: ×"####.###";dëDAYENTERìDAYTOTAL;:" % ";:" DAYS TOTAL LIFETIME ";: ×"##.###^^^^";DAYTOTAL;:" " +ZØÊ ,3:" DAYS PREDICTED ";: ×"##.###^^^^";PREDICT;:" " iZâÊ ,: " LAST TIME STEP (sec) = ";: ×"##.##^^^^";DT;: ±Zì :*** to calculate/display relation of real to simulated time. ÄZöÊ ,:" WAS" ÿZ KMç Í 2
: *** display initial values, nm units. :[
KMç Í Z
: *** display initial values, km units. @[ L[ ------ w[(--- DISPLAY G FORCE WHEN NEAR REENTRY ¯[2Ê ,<:" G's =";: ×"####.####";FORCEHLDì( ÍÌ ëM) µ[< Á[F------ í[P--- FINAL QUIT ROUTINE FOR ALL SCREENS J\ZÊ ,:¿ ,:" HIT `c' TO RETURN TO SELECTION SCREEN, HIT `e' TO EXIT TO DOS ": ¿ , y\d z:*** purge inkey of stray keystrokes \nZ3$çÞ: ÿ(Z3$)ç Í n ¾\x ÿ(Z3$)çe Í þ : *** exit to DOS õ\ ÿ(Z3$)çc Í ¬ :¡ n: *** begin another case 5]: *** return ineffective; only way out is new case or DOS A]------ ] ---ROUTINE FOR OPTION INSTRUCTION ON BOTTOM OF DISPLAY SCREEN Û]ªÀ:Ê ,:" **** Hit `o' to toggle sound on/off, `p' to pause, or
,:" INITIAL ALTITUDE TOO LOW FOR THIS CASE. TRY A SMALLER TIME INCREMENT, LIKE 10" a^Ê ,:" MAYBE YOU WILL EVEN HAVE TO START AT A HIGHER ALTITUDE." Hah P:*** to routine for choice of new case or exit to DOS. ar: *** return ineffective; only way out is new case or DOS a|------ Õa---ROUTINE IF INITIAL ALTITUDE LESS THAN 12 NAUTICAL MILES. èa ISOUNDç Í Å 3bÀ:Ê
,:" INITIAL ALTITUDE MUST BE GREATER THAN 12 NAUTICAL MILES. " tb¤ P:*** to routine for choice of new case or exit to DOS. ´b®: *** return ineffective; only way out is new case or DOS Àb¸------ þbÂ---ROUTINE IF INITIAL ALTITUDE OVER 1000 NAUTICAL MILES. cÌ ISOUNDç Í Å `cÖÀ:Ê
,:" INITIAL ALTITUDE CAN'T BE GREATER THAN 1000 NAUTICAL MILES. " ¡cà P:*** to routine for choice of new case or exit to DOS. ácê: *** return ineffective; only way out is new case or DOS ícô------ 5dþ--- ROUTINE IF MASS, CROSS-SECTION, OR TIME INCREMENT ARE NEGATIVE Hd ISOUNDç Í Å dÀ:Ê
,:" VALUES OF";ZERROR$;" CAN'T BE ZERO OR LESS. " Çd P:*** to routine for choice of new case or exit to DOS. e&: *** return ineffective; only way out is new case or DOS e0------ Oe:--- TO TOGGLE ISOUND BETWEEN 0 AND 1 (SOUND OFF OR ON) keD ISOUNDç Í N :¡ X zeNISOUNDç: eXISOUNDç: eb------ ¸el--- MAKE INITIAL ALTITUDE BAR ÉevZBAR$çÿ(Û) Øe Kç Ì F ïeZBAR$çZBAR$éÿ(°) ÷e K f PRINT ZBAR$ Of¨ Û°°°°(looks like this)°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°° Îf² The above graphic displayed here by PRINTing it, then labeling with a line number, then making it a REM statement. Ôf¼ àfÆ------ 'gÐ--- ROUTINE FOR PRINTING TO SCREEN THE TEXT FILE FOR THIS PROGRAM TgÚÀ:º "I",,"SATFLY11.DOC": *** text file ggä IREADç Ì gî ÿ£() Í >: to prompt for return to opening screen of program Àgø° #, ZTEXT$ Íg ZTEXT$ Ùg IREAD hÊ ,:" *** HIT ANY KEY TO READ MORE *** " :h z:*** purge inkey of stray keystrokes ah*ZREAD$çÞ: ÿ(ZREAD$)ç Í * :¡ À h4 ä: *** read next page of document h>» # ÔhHÊ ,:" *** HIT ANY KEY TO RETURN TO DRAG PROGRAM *** " iR z:*** purge inkey of stray keystrokes %i\ZREAD$çÞ: ÿ(ZREAD$)ç Í \ Fif: *** to selection screen. Rip------ iz--- ROUTINE TO PURGE INKEY BUFFER SO STRAY STROKES DONT CONFUSE THINGS. jZPURGE$ç"1": *** makes sure inkey buffer has something in it before the purging loop begins next. j±é ÿ(ZPURGE$)æ QjZPURGE$çÞ: *** takes next value from buffer Wj¢² ]j¬ ij¶------ ´jÀ--- ROUTINE FOR FINDING SPEED OF MACHINE BEING USED & SET SPEED FLAGS ÌjÊZTIMER$çþ:ICOUNTç õjÔ±é ÿ(ÿ(ZTIMER$,))ê ÿ(ÿ(þ,))ç kÞ²:*** waits for the start of a second NkèZTIMER$çþ: *** record the starting time kò ÿ(ÿ(ZTIMER$,))æ9 Í Ê:*** don't try if near 0 seconds ºkü±é ÿ(ÿ(ZTIMER$,))ê ÿ(ÿ(þ,))æê ÎkICOUNTçICOUNTé ùk²:*** continue count for two seconds. :lITIMEç ÿ(ÿ(þ,)): *** end second of 2 second measurememt wl$SPEEDçICOUNTì:*** cycles per second for the above loop ôl. ITIMEè Í SPEEDçSPEEDì :*** accounts for higher speeds being calculated for seconds under 12 in a minute. *m8ISPEEDçÿ (SPEED): *** puts speed in integer form imB ISPEEDæ Í IMACHINEç :*** is machine 386,AT, or XT ? mL IMACHINEç Í `:*** if true, then is 386 ÕmV ISPEEDæÈ Í IMACHINEç :¡ IMACHINEç:** AT else XT mn`IPATCHç-ëIMACHINE:IFLICKERçëIMACHINE:IFLASHçÿ (ÿ(dëIMACHINE)):ICALCçëIMACHINE: *** sets display/calculation cycle values so visuals are good. µnj ICALCç Í ICALCç:*** adjust XT calculations per display upwards »nt Çn~------ o--- ROUTINE FOR DISPLAYING RATIO OF REAL TIME TO SIMULATED TIME BoRATTIMEçDTëISPEEDëOPTIME:*** calculate the ratio co RATTIMEæ ù¢ Í ì :¡ ° io¦ o° RATTIMEæ
Í
:¡ Ä oº ¯oÄ RATTIMEæç Í ( :¡ Ø µoÎ ÚoØ RATTIMEæ ¬Å'p Í F :¡ d àoâ "pì*-- DISPLAY REAL TIME RELATION FOR GREATER THAN 1E+10 FASTER pöÊ ,:" NOW FLYING ABOUT";: ×"##.##^^^^";ÿ (RATTIME);:" TIMES FASTER THAN REAL TIME " p Òp
*-- DISPLAY REAL TIME RELATION FOR > 10, <1E+10 TIMES FASTER ;qÊ ,:" NOW FLYING ABOUT";: ×"#############,";ÿ (RATTIME);:" TIMES FASTER THAN REAL TIME " Aq ~q(*-- DISPLAY REAL TIME RELATION FOR 1 TO 10 TIMES FASTER áq2Ê ,:" NOW FLYING ABOUT";: ×"###,.##";RATTIME;:" TIMES FASTER THAN REAL TIME " çq< (rF*-- DISPLAY REAL TIME RELATION FOR > 1, < 1E+5 TIMES SLOWER rPÊ ,:" NOW FLYING ABOUT ";: ×"######,.#";ìRATTIME;:" TIMES SLOWER THAN REAL TIME " rZ Ôrd*-- DISPLAY REAL TIME RELATION FOR > 1E+5 TIMES SLOWER AsnÊ ,:" NOW FLYING ABOUT ";: ×"##.##^^^^";ìRATTIME;:" TIMES SLOWER THAN REAL TIME " Gsx Ss------ s--- CALCULATE SEMILOG COEFFICIENTS FOR STANDARD ATM DENSITY MODEL ©s Iç Ì ñs DENCOEFF(Ié,)ç(Cëÿ(DS(Ié,))êCëÿ(DS(I,)))ì(DS(Ié,)êDS(I,)) MtªDENCOEFF(Ié,)ç(Cëÿ(DS(Ié,))éCëÿ(DS(I,)))ìêDENCOEFF(Ié,)ë(DS(Ié,)éDS(I,))ì Ut´ I [t¾ gtÈ------ ±tÒ--- CALCULATES SEMILOG COEFFICIENTS FOR HIGH SOLAR ATM DENSITY MODEL ÀtÜ Iç Ì uæDENCOEFF(Ié,)ç(Cëÿ(DH(Ié,))êCëÿ(DH(I,)))ì(DH(Ié,)êDH(I,)) duðDENCOEFF(Ié,)ç(Cëÿ(DH(Ié,))éCëÿ(DH(I,)))ìêDENCOEFF(Ié,)ë(DH(Ié,)éDH(I,))ì luú I ru ~u------ Çu--- CALCULATES SEMILOG COEFFICIENTS FOR LOW SOLAR ATM DENSITY MODEL Öu" Iç Ì v,DENCOEFF(Ié,)ç(Cëÿ(DL(Ié,))êCëÿ(DL(I,)))ì(DL(Ié,)êDL(I,)) zv6DENCOEFF(Ié,)ç(Cëÿ(DL(Ié,))éCëÿ(DL(I,)))ìêDENCOEFF(Ié,)ë(DL(Ié,)éDL(I,))ì v@ I vJ vT------ w^--- ERROR TRAPPING FOR EXTREME VALUES, SOUND COMMAND PROBLEMS, MISSING TEXT DOCUMENT, ANY OTHER ERROR. Bwh Õç Í à:*** to announce out of range value set. swr Õç Í :*** start over because of error. ´w| Õç5 Í :*** reports document not found, allows rerun õw Õç5 Í :*** need to rerun to allow future error trapping $xÀ:Ê ,:" ERROR NUMBER ";Õ;" ON LINE ";Ô {xÊ ,:" I CAN'T HANDLE THAT ERROR. YOUR ACTION OR YOUR BASIC IS UNUSUAL TO ME. " Îx¤Ê ,:" I CAN RUN UNDER BASICA OR GWBASIC. MAYBE I'M JUST OVERLOADED NOW. " y®Ê ,:" TRY NOT USING SOUND. HIT ANY KEY TO RETURN TO DRAG PROGRAM " My¸ z:*** purge inkey of stray keystrokes iyÂZ1$çÞ: ÿ(Z1$)ç Í Â oyÌ uyÖ¨ ³yà*-- ROUTINE FOR STATING OUT-OF-RANGE VALUE SET CONDITION zêÀ:Ê
,:" THE VALUE SET YOU SELECTED IS TOO EXTREME TO BE CALCULATED IN THIS PROGRAM. " OzôÊ ,:" TO RETURN TO SELECTION SCREEN, PRESS ANY KEY. " ~zþ z:*** purge inkey of stray keystrokes zZ1$çÞ: ÿ(Z1$)ç Í z æz *-- ROUTINE FOR REPORTING DOCUMENT NOT FOUND, AND ALLOWING RERUN {&À:Å:Ê
,
:" *** SATFLY11.DOC not found *** " s{0Ê ,
:" Contact Bill Cuneo, (301) 9775778 for information, if necessary. " ®{:Ê ,
:" HIT ANY KEY TO RETURN TO DRAG PROGRAM " Ý{D z:*** purge inkey of stray keystrokes ù{NZ1$çÞ: ÿ(Z1$)ç Í N ÿ{X
Very nice! Thank you for this wonderful archive. I wonder why I found it only now. Long live the BBS file archives!
This is so awesome! 😀 I’d be cool if you could download an entire archive of this at once, though.
But one thing that puzzles me is the “mtswslnkmcjklsdlsbdmMICROSOFT” string. There is an article about it here. It is definitely worth a read: http://www.os2museum.com/wp/mtswslnk/