\X START\READ PR_ORDER.MAC\ON KEY F10 JUMP MASTER\+
\X BEGIN\CLEAR SCREEN\MOVE 1 TO #1003
\X AIRFOIL\ON KEY 7181\ON KEY 18688\ON KEY 20736\+
\ON ERROR JUMP WAYTOOSMALL\CLEAR PICS\APPEND AIRFOIL7.PIC 1,6
\ON ERROR JUMP NONEWFONT
\READ FONT_USA.FON\CLEAR ON ERRORS\JUMP NEWFONT
\X NONEWFONT\READ 081119PW.FON
\X NEWFONT\LOC 0,0\WID 20 C\HEI 40\OVE 0
HOW AN AIRPLANE
WING PROVIDES LIFT
\SHOW 80,76,1\READ 081119PW.FON
\LOC 0,42\WID 207 DOTS\HEI 12\SCRO 0,X,43
Direction of Forward Motion
\DRAW C43J5,63,R212G5U1E5H5D1F4L211
\LOC 222,68\WID 55 DOTS C\HEI 24\SCRO 0,X,33
LEADING
EDGE
\LOC 8,68\WID 65 DOTS C
TRAILING
EDGE
\LOC 20,108\WID 280 DOTS\HEI 120\OVE 1,A,217
This cross-section view of an airplane
wing shows that the wing bulges at the
top near the front and then tapers to a
point at the back.  This shape forces
the air to flow in a downward direction.
The downward force has an equal and
opposite upward force on the wing.
\LOC 20,100\WID 280 DOTS\HEI 99\OVE 1,A,222
\BL 0,188,319,200\JUMP PROPS\X PASTKEY\ON KEY 7181
\BL 8,68,71,92\BL 0,0,40,38\BL 280,0,319,38
\BL 220,69,278,92\+
\LOC 20,108\WID 280 DOTS\HEI 120\OVE 1,A,218
When the airplane is moving very slowly,
as when taxiing or starting its takeoff
run, even pressure is exerted above and
below the wing and therefore it cannot
lift the airplane.  Here, greatly en-
larged air molecules are shown passing
over and under the wing.
\CLEAR SPRITES\ROUNDS #1143 SPEED 7
\SPRITE P=3,1 T=R X=A L=-7,-5\SPRINT 2
\SPRITE P=4,29\SPRINT 2\SPRITE P=3,59\SPRINT 2
\SPRITE P=4,89\SPRINT 2\SPRITE P=3,119\SPRINT 2
\SPRITE P=4,149\SPRINT 2\SPRITE P=3,179\SPRINT 2
\SPRITE P=4,209\SPRINT 2\SPRITE P=3,239\SPRINT 2
\SPRITE P=4,279\SPRINT 2\ON KEY 7181 JUMP CONT4
\RUN
\X CONT4\ON KEY 7181\BL 0,68,79,107\BL 80,69,200,75
\BLANK 0,108,19,177
\SHOW 80,76,1\BL 80,92,200,107\BL 200,69,319,107
\READ 081119PW.FON\LOC 20,108\WID 280 DOTS\HEI 100\OVE 1,A,222
The air passing over the wing travels
further and faster than the air which
passes under the wing.  As the airplane
picks up speed, this causes the pressure
on top to be lower than on the bottom.
The air is pushed down, and the wing is
pushed in the opposite direction, up.
\LOC 30,188\HEI 12\OVE 0,A,221
      Press <RETURN> to continue...
\LOC 240,42\WID 75 DOTS C\HEI 24\SCRO 0,X,35
Direction
of lift
\DRAW J234,41C35F4D1H5L1G5U1E5D27R1U27
\CLEAR SPRITES\ROUNDS #1143 SPEED 7
\SPRITE P=5,1 T=R X=A L=-5,-7
\SPRITE P=6,19\SPRINT 2\SPRITE P=5,39\SPRINT 2
\SPRITE P=6,59\SPRINT 2\SPRITE P=5,79\SPRINT 2
\SPRITE P=6,99\SPRINT 2\ON KEY 7181 JUMP CONT5
\RUN
\X CONT5\ON KEY 7181\BL 0,68,79,107\BL 80,69,200,75
\BLANK 0,108,19,177
\SHOW 80,76,1\BL 80,92,200,107\BL 200,69,319,107
\LOC 20,108\WID 280 DOTS\HEI 100\OVE 1,A,224\READ 081119PW.FON
It should be noted that the propeller or
jet engine serves merely to move the
wing (and the airplane) forward through
the air, but they do NOT provide the
lift.  The distinctive shape of the wing
--known as an AIRFOIL--is what causes
the airplane to fly.
\CLEAR SPRITES\ROUNDS #1143 SPEED 4
\SPRITE P=5,1 T=R X=A L=-5,-7\SPRINT 2
\SPRITE P=6,19\SPRINT 2\SPRITE P=5,39\SPRINT 2
\SPRITE P=6,59\SPRINT 2\SPRITE P=5,79\SPRINT 2
\SPRITE P=6,99\SPRINT 2\ON KEY 7181 JUMP MASTER
\RUN
\X MASTER\READ #97:MENU.TXT
\*
\X PROPS\ROUNDS #1141*30 SPEED 7\CLEAR SPRITES
\LOC 30,188\HEI 12\OVE 0,A,220
      Press <RETURN> to continue...
\ON ERROR JUMP NOPROPS\APPEND AIRFOIL7.PIC 7,-1\CLEAR ON ERRORS
\SPRITE L=10,10 A=1 F=Y\SPRINT 7 TO 22
\SPRITE L=1060,1060 A=NO \SPRINT 1
\SPRITE L=280,10 A=1 F=Y\SPRINT 14 TO 22\SPRINT 7 TO 13
\ON KEY 7181 JUMP PASTKEY
\RUN\JUMP PASTKEY
\X NOPROPS\WAIT NOW #1141*50\JUMP PASTKEY
\X WAYTOOSMALL\CALLM WAY2SMALL\END
