BA 111 Simulator (Airliner) - Rod Hopkins (Your Computer-December 82-Page 38)

Rod Hopkins applies his knowledge of multi-million pound pilot trainers to
produce the most realistic simulator ever published for a home computer.

THIS FLIGHT simulator is a fairly elaborate program leaving little memory to
spare in a 16K Spectrum. In consequence, a methodical approach to some reso-
lute typing is demanded of the would-be pilot.
 Firstly, type in the main program, listed in figure 1, Saving it in auto-run
mode:
        SAVE "BA 111" LINE 1
 Having vertified the recording, turn to the machine-code dump in figure 2.
Enter this code by way of a short routine such as the following:
        9990 FOR N=1 TO 236: PRINT 23295+N,: INPUT "Enter byte",I:
             POKE 23295+N,I: PRINT I: NEXT N
 This procedure allows checking of each byte as entered. Once complete, the
code should be saved immediately following the main program on tape:
        SAVE " " CODE 23296,236
 Again, verify the recording. Leave the tape set at the end of the code and
type in the screen-plotting routine listed in figure 3.
 Now type Run, switch the recorder to record, press Enter, and the display
will be saved. In future, the screen will be loaded directly from tape by the
main program; but to be on the safe side, save the plotting routine elsewhere.
 Next a little guidance on using the program. In the first place, do not ex-
cept flying an aircraft to be too easy. Figure 4 enumerates the controls used
- familiarise yourself with them before running. Note that the method of key-
board decoding used means that a single, brief key-press will be read. Notice
also that some controls operate as on/off switches.
 Shortage of RAM precludes any attempt at making the program completely bomb-
proof, though most of the silly possibilities which delight bug-hunters have
been foreseen. For example, the undercarriage cannot be raised on the ground,
and the brakes will not work in the air! Figure 5 gives a concise chart of the
area around Edinburgh Airport, the arena of the simulation, showing beacons
and two runways. This chart is available on a CRT monitor in the cockpit du-
ring run time. Navigation is by means of the beacons, which provide two types
of information. First, radial: this is your bearing from the beacon in use;
and secondly, DME: distance from the beacon - Distance Measuring Equipment.
 Beacons EDN and UWB must be used to approach the runways. Radial and DME are
displayed on the central panel of the cockpit, to the right of which a head-up
display indicates the direction of the beacon by a flashing cursor in relation
to the plane's heading.
 The CRT monitor mentioned serves three purposes: it defaults to an artificial
horizon display, the plane being viewed from the rear over a horizon which
swings in proportion to roll, attitude, lift. Secondly, map: this gives beacon
positions, and that of the plane if within the boundaries of the display - a
dot within a flashing square. The latter is not updated while the map is ac-
cessed. Third, a view of the runway while landing.
 Some final points about the cockpit. Warning lights are provided for brakes
on, gear up when landing, emergency fuel, plane descending - Rate of Climb
becomes Rate of Descent - and plane approaching out-of-control condition.
 In connection with the last mentioned, remember to increase power/speed/flap,
to increase lift. Both ROC and ALT meters show thousands of feet in the top
window, feet in the lower.
 Take-off will not be achieved at speeds less than 100 knots, or with an alti-
tude less than 10. For Landing, bearings are given on the chart. Try to ap-
proach on a glide path - insurance against engine trouble - losing height at
around 6-800 feet a minute. The CRT will not indicate permission to land, that
is when the runway is shown, unless your angular approach is viable +-10
degrees of ideal. Once committed to landing, the attempt must be seen through.
To practise landing, define your location at the prompts with:
 Beacon?="EDN"; Radial?=70; Heading?=250; DME?=2. Increase flap angle to main-
tain lift as speed falls, and do not forget to brake fairly quickly after
touchdowm, when the altimeter shows 10 feet, as the runway is not indefinitely
long.
 Figure 6 gives a breakdown of the components of the program. For the interes-
ted who do not have the stamina or the time to type in the simulator themsel-
ves, a cassette of the complete program is available for 3 from the author,
Rod Hopkins, at 116 Pilmuir Street, Dunfermline, Fife, Scotland.

FIGURE 4. Keyboard decoding.

KEYPRESS        FUNCTION
B               Brakes on/off
C               Change beacon
D/U             Down/Up
R/L             Right/Left
J(-)/K(+)       Less more flap
P               Power increase, stop decrease
O               Power decrease, stop increase
M               Map on/off
G               Gear up/down

FIGURE 6. Program breakdown.

FROM    TO      FUNCTION
   5     240    Main flying loop
2000    2070    Flap
2100    2108    Power
2110    2116    Roll
2120    2129    Attitude
2500    2515    Gear
2520    2546    Map
2580    2595    Update variables
8500    8810    Landing routine
9000    9020    Brakes
9500    9502    Head-up
9510    9511    Beacon
9520    9522    Out of control
9530    9545    Artificial horizon
9550    9560    Take-off set-off
9640    9644    Fuel
9650    9665    Initialising subroutine
9680    9682    Exit / messages
USR    23296    Clear monitor during landing
USR    23391    Update instruments
USR    23483    Print Plane

TYPE: Flight Simulator

AIRLINER.TAP is the released version from Protek called Airliner.

BA111SIM.TAP is the original version from Your Computer, including
the corrections from the Jan'83 issue. [JimG]


This info file was typed by Michael Bruhn
