BCG101/port/ROCKT1.BAS

  70 PRINT "LUNAR LANDING SIMULATION"
  80 PRINT "----- ------- ----------"\PRINT
 100 PRINT "DO YOU WANT INSTRUCTIONS (YES OR NO)";\INPUT A$
 110 IF A$="NO" THEN 390
 160 PRINT
 200 PRINT "YOU ARE LANDING ON THE MOON AND HAVE TAKEN OVER MANUAL"
 210 PRINT "CONTROL 500 FEET ABOVE A GOOD LANDING SPOT.  YOU HAVE A"
 220 PRINT "DOWNWARD VELOCITY OF 50 FT/SEC.  120 UNITS OF FUEL REMAIN."
 225 PRINT
 230 PRINT "HERE ARE THE RULES THAT GOVERN YOUR SPACE VEHICLE:"
 240 PRINT "(1) AFTER EACH SECOND, THE HEIGHT, VELOCITY, AND REMAINING"
 250 PRINT "    FUEL WILL BE REPORTED."
 260 PRINT "(2) AFTER THE REPORT, A '?' WILL BE TYPED.  ENTER THE"
 270 PRINT "    NUMBER OF UNITS OF FUEL YOU WISH TO BURN DURING THE"
 280 PRINT "    NEXT SECOND.  EACH UNIT OF FUEL WILL SLOW YOUR DESCENT"
 290 PRINT "    BY 1 FT/SEC."
 310 PRINT "(3) THE MAXIMUM THRUST OF YOUR ENGINE IS 30 FT/SEC/SEC OR"
 320 PRINT "    30 UNITS OF FUEL PER SECOND."
 330 PRINT "(4) WHEN YOU CONTACT THE LUNAR SURFACE, YOUR DESCENT ENGINE"
 340 PRINT "    WILL AUTOMATICALLY CUT OFF AND YOU WILL BE GIVEN A"
 350 PRINT "    REPORT OF YOUR LANDING SPEED AND REMAINING FUEL."
 360 PRINT "(5) IF YOU RUN OUT OF FUEL, THE '?' WILL NO LONGER APPEAR,"
 370 PRINT "    BUT YOUR SECOND BY SECOND REPORT WILL CONTINUE UNTIL"
 380 PRINT "    YOU CONTACT THE LUNAR SURFACE."\PRINT
 390 PRINT "BEGINNING LANDING PROCEDURE....."\PRINT
 400 PRINT "G O O D   L U C K ! ! !"
 420 PRINT\PRINT
 430 PRINT "SEC  FEET   SPEED    FUEL      PLOT OF DISTANCE"
 450 PRINT
 455 T=0\H=500\V=50\F=120
 490 PRINT T;TAB(4);H;TAB(12);V;TAB(20);F;TAB(29);"I";TAB(H/12+29);"*"
 500 INPUT B
 510 IF B<0 THEN 650
 520 IF B<=30 THEN 530\B=30
 530 IF B<=F THEN 540\B=F
 540 V1=V-B+5
 560 F=F-B
 570 H=H-.5*(V+V1)
 580 IF H<=0 THEN 670
 590 T=T+1
 600 V=V1
 610 IF F>0 THEN 490
 615 IF B=0 THEN 640
 620 PRINT "*** OUT OF FUEL ***"
 640 PRINT T;TAB(4);H;TAB(12);V;TAB(20);F;TAB(29);"I";TAB(H/12+29);"*"
 650 B=0
 660 GOTO 540
 670 PRINT "*** CONTACT ***"
 680 H=H+.5*(V+V1)
 690 IF B=5 THEN 720
 700 D=(-V+SQR(V*V+H*(10-2*B)))/(5-B)
 710 GOTO 730
 720 D=H/V
 730 V1=V+(5-B)*D
 760 PRINT "TOUCHDOWN AT";T+D;"SECONDS."
 770 PRINT "LANDING VELOCITY =";V1;"FT/SEC"
 780 PRINT F;"UNITS OF FUEL REMAINING."
 790 IF V1<>0 THEN 810
 800 PRINT "CONGRATULATIONS!!    A PERFECT LANDING!"
 805 PRINT "YOUR LICENSE WILL BE RENEWED.......LATER."
 810 IF ABS(V1)<2 THEN 840
 820 PRINT "***** SORRY, BUT YOU BLEW IT!!!!"
 830 PRINT "APPROPRIATE CONDOLENCES WILL BE SENT TO YOUR NEXT OF KIN."
 840 PRINT\PRINT\PRINT
 850 PRINT "ANOTHER MISSION";\INPUT A$
 860 IF A$="YES" THEN 390
 870 PRINT\PRINT "CONTROL OUT."\PRINT
 999 END