FLIGHT PLAN PROGRAM - AIRCRAFT PERFORMANCE SCREEN    RELEASE 3.10   PAGE 1 OF 7

The purpose of this screen is to allow interactive changing of the cruise per-
formance, climb performance or fuel status.  Parameters for three aircraft can
be stored on the disk.  The aircraft are identified as 1 of 3, 2 of 3, and 3 of
3; in addition you can enter an identifier and short description for each air-
craft.  The aircraft you want to use is made active by using the PgUp and PgDn
keys.  A flight plan is computed only for the active aircraft, which is the one
for which performance data is visible on your screen.

A number is selected for change by pressing the up- and down-arrow keys to move
the solid video block to the required item.

*** CHECK DENSITY ALTITUDE!***  DO NOT forget to enter the correct surface tem-
perature at the departure point!  This data item is used to calculate the den-
sity altitudes on which aircraft performance calculations are based.

WARNING: THE AUTHOR IS NOT RESPONSIBLE FOR THE ACCURACY OF ANY PERFORMANCE OR
OTHER DATA ENTERED BY THE USER INTO THE FLIGHT PLAN SYSTEM.  YOU MUST ENTER
DATA FOR THE AIRCRAFT YOU FLY - DO NOT TRUST ANY PERFORMANCE DATA SUPPLIED WITH
THE PROGRAM FOR DEMONSTRATION PURPOSES.


FLIGHT PLAN PROGRAM - AIRCRAFT PERFORMANCE SCREEN                   PAGE 2 OF 7

In this version of the program, distances and speeds can be entered and re-
ported in nautical miles, statute miles or kilometers.  The choice is made in
the SETUP screen by pressing the D key.  If you want to change that option, do
it now before entering winds aloft, etc.  Press Esc, then T, then Y, then X if
you want to get to the SETUP/Master Menu screen right now.

All airspeeds to be entered are indicated airspeeds (actually, you should enter
calibrated airspeeds).  DO NOT enter true airspeeds; the program computes them.
All fuel flows and fuel quantities may be entered in either gallons or pounds,
as long as the SAME unit is employed consistently each time the program is run.
Use the numbers for all engines combined if you fly a multi-engine plane.

All temperatures are entered and displayed in degrees F.  The program assumes a
temperature gradient of 3.6 degrees F. per 1000 feet of elevation.  This number
is important in computing climb performance and other factors.

The next two screen pages describe each of the available menu functions.  After
that, there is more information about aircraft performance parameters.



FLIGHT PLAN PROGRAM - AIRCRAFT PERFORMANCE SCREEN                   PAGE 3 OF 7

W = WINDS aloft.  First, you are asked if you want to fly under VFR (Visual
    Flight Rules).  Reply Y (for Yes) to fly VFR, N (for No) to fly under IFR
    (Instrument Flight Rules), or press Esc to cancel the winds aloft function.
    The program will automatically compute correct altitudes which correspond
    to the direction of flight and whether you are VFR or IFR.

    Next, you are taken to another screen which will ask for winds aloft for
    each leg of the flight.  You can enter winds aloft for any altitude(s)
    (within the limits of where your airplane is capable of flying).  The
    program will compute winds aloft for all altitudes for which you did not
    specify any winds.

    Finally, you will see the altitude select screen.  At this point, flight
    plans have already been computed for each altitude you can fly at.  The al-
    titude select screen displays a summary of the flight plan for each alti-
    tude.  You can then select the altitude you want to fly at, depending on
    total flight time, fuel requirements, etc.  The altitude select screen has
    its own HELP function for more information.



FLIGHT PLAN PROGRAM - AIRCRAFT PERFORMANCE SCREEN                   PAGE 4 OF 7

A = ALTITUDE select.  This function is identical to the WINDS aloft function
    described previously, except it does not ask for winds aloft.  After speci-
    fying whether you want to fly VFR or IFR, you are taken directly to the
    Altitude Select screen. Flight plans are computed under no-wind conditions.
    You can still enter winds aloft for individual trip legs later on.

C = CHANGE the selected data item.  The new value must be in between the limits
    specified in the prompt, inclusive.  All values must have been entered and
    must be within limits before a flight plan can be computed for the active
    aircraft.  All values are automatically saved on disk when you switch to
    any other screen display.  Note: the same surface temperature at the depar-
    ture point is used for all three aircraft.

T = TRIP display screen.  This function will re-display the active trip.
    Warning: any winds aloft values you have typed in will be lost!  Winds
    aloft are not stored on disk.

H = HELP - displays the information you are reading now.



FLIGHT PLAN PROGRAM - AIRCRAFT PERFORMANCE SCREEN                   PAGE 5 OF 7

                          ABOUT AIRCRAFT PERFORMANCE

In general, aircraft performance is usually more or less linear (that is, it
changes at a constant rate) from sea level up to a certain intermediate alti-
tude.  Above that, performance tapers off more rapidly up through the air-
plane's service ceiling.  That is why the program asks for performance values
at three different altitudes: sea level, an intermediate altitude, and the
service ceiling (the altitude at which an aircraft can climb only 100 f.p.m.).

Performance data is entered for ISA (standard atmosphere) conditions.  The pro-
gram assumes standard conditions to include a temperature of 59 degrees F. at
sea level, decreasing 3.6 degrees F. each 1,000 feet.  The program calculates
actual aircraft performance based on DENSITY altitudes that correspond to the
ACTUAL altitudes you will see on the screen.  That is why it is VERY IMPORTANT
to enter the correct surface temperature at the departure point.

For example, if you depart Santa Fe, NM (elevation 6,344 ft. above sea level)
and the surface temperature is 93 degrees F., the density altitude will be TEN
THOUSAND FEET and the program will calculate climb performance at that altitude
rather than the actual airport altitude.  But can you take off at all?

FLIGHT PLAN PROGRAM - AIRCRAFT PERFORMANCE SCREEN                   PAGE 6 OF 7

Most performance data can usually be obtained from the Pilot's Operating Hand-
book (P.O.H.) or the manufacturer's aircraft information manual.  It can then
be "fine-tuned" as required, based on flight experience.  For several flights,
keep a record of the climb time and fuel used every 1000 feet,  the fuel flow
and outside air temperature in cruise and any other required information.

For normally aspirated piston-engined aircraft, try an intermediate altitude of
5,000 ft. for climb and 9,000 feet. for cruise at 65% power, to start with.
For turbocharged piston-engined aircraft, performance varies widely with the
type of aircraft - you will have to refer to your P.O.H.  WARNING: although the
author of this program is a licensed pilot, he does NOT have experience in tur-
bine aircraft!  Advice (and criticism) is welcome.

WARNING: Performance calculations may be inaccurate - on the optimistic side -
near the service ceiling.  The performance data you enter should reflect the
greatest accuracy at the altitudes you normally fly at.

Note: It may be necessary to "juggle" performance numbers around a bit, based
on personal experience with the aircraft you fly, to get the best results.
Remember that old computer axiom: Garbage In, Garbage Out!

FLIGHT PLAN PROGRAM - AIRCRAFT PERFORMANCE SCREEN                   PAGE 7 OF 7

                            INFORMATION ABOUT FUEL

The total useable fuel on board is that which is actually available, and does
not necessarily have to be the maximum fuel capacity.

The fuel allowance for taxi, runup and takeoff can usually be obtained from the
pilot operating handbook.  If not, try 1 gallon per 2400 lbs. gross weight, or
more than that if you taxi a long distance.

WARNING: It is the author's experience that fuel consumption figures in many
Pilots' Operating Handbooks are optimistic, especially if you value the health
and longevity of your engine(s)!  Check out your ACTUAL fuel consumption based
on experience, and then use those numbers in the Flight Plan System.
