Editing Aircraft Data
Before you can create an accurate flight plan, you need accurate aircraft
data. JIFP comes with a number of preloaded aircraft models, but you should
check and edit the model you intend to use so that it accurately reflects
your aircraft. If you do not see your type of aircraft in JIFP, you might
have to create an aircraft model from scratch. However, choosing a model
that is similar to yours and then modifying it might be easier. This approach
is recommended, even if you have to change every value. If a change occurs
in the performance model, you must change all of the performance values,
as well as all weight and balance values. Still, using the similar aircraft
type gives you a good template for entering your data.
Select a pilot aircraft model in the Aircraft Library
Manager dialog box by clicking Edit > Aircraft
Data > Select Aircraft Data. After a selection is made, click
Edit to make changes. It is best to enter aircraft
model data in the following sequence:
Choosing a
Sample Aircraft
Basic Aircraft
Data
Weight and
Balance Data
Performance
Data
Top 12 Errors Made in Creating or Editing Aircraft Models
The following list highlights common calls that technical support receives
regarding creating or editing aircraft models.
Leaving necessary
performance fields blank —
The program cannot identify the difference between leaving data out and
adding a zero. Any spaces that are left empty are assumed to have a value
of zero; the program calculates on that zero, causing an error in calculation.
Not
completing the envelope in the Weight & Balance tab — If the envelope does not appear
gray, it is not seen by the program as a closed envelope. The program
cannot be certain if you are inside or outside.
Not
entering any weight and balance information —
Even if you are only using the program for performance, if the weight
and balance data is incorrect, it can affect the performance numbers.
Basic models assume performance based on weight; thus, if the weight is
incorrect, the model cannot be accurate.
Incorrect
performance information —
Often a model appears to work correctly except at a certain altitude or
weight. This situation is usually the result of a typo, such as entering
1227 instead of 127 for a speed in a single field. The program averages
and interpolates information so that it is accurate at speeds and weights
between the entered data. One error can cause any flight near the data
error to be affected.
In
the Basic Info tab, not matching the fuel capacity with the information
under the Weight & Balance tab —
The two tabs should indicate the same quantity of fuel, even if one is
in gallons and the other is in pounds.
Not
specifying that the fuel stations are type 'Fuel' in the Weight &
Balance section —
This situation results when the program does not allow you to enter fuel
when clicking Preflight > Weight & Balance for
[route]. If you make the change, and the fuel in the navlog does
not change or shows zero fuel, this might be the cause.
Entering
Moment instead of CG for performance —
If the envelope is narrow and angular, it is probably not a CG envelope.
Trying
to create a Constant Power model when the POH gives Constant Altitude
data, or vice versa —
In this situation, there is no correct way to complete the model and get
satisfactory performance. Either one can be a good basic model, but model
templates only support the type of data for which the POH is written.
Entering
fuel in a different unit from that specified in the Aircraft Setup Information
tab — If the
Aircraft Setup Information tab has the units for fuel, speed, and so on,
set as one type of unit, the performance tabs and Basic Info tab must
use the same units. Weight and balance are the only exceptions: they are
always in weight units, never in liquid measure.
Entering
too little data for a configuration —
The program is set up for groups of three. Any weight, altitude, power
setting, and so on, needs at least three entries to average correctly.
If too little data is entered, the program does not let you plan with
the model.
Not
entering +20 and -20 information for Constant Power and Constant Altitude
models — Even
if you only want to assume standard conditions, the program registers
the zeros and assumes it is valid data.
Leaving
the Climb & Descent information blank in the Basic Information tab
— If this information
is left at zero, the program assumes it is valid data and plans with it.