
	 ___ _____ _____ 
	|_ _|  ___|_   _|  Instrument
	 | || |_    | |    Flight
	 | ||  _|   | |    Trainer
	|___|_|     |_|  
                 

IFT is a small flight simulator written for the purpose of training
pilots not experienced in instrument flight. It includes a couple of
VOR and NDB stations and displays. These can be used to exercise basic
radio navigation skills.

It's made and tested on GNU/Linux, but it should work on all Unices,
since all it uses is the X11 library.

USAGE

There are two programs in the IFT package. One of them is 'fly', which
is the simulator program. The other one is called 'holding'. It's
explained in more detail below.

When you run the program 'fly', it provides you with a partial cockpit
with two ADF and two VOR displays in addition to the heading and
turn & slip dials. The radio navigation equipment is functional all
the time, no matter how far you're away from the station.

When you press the 'Esc' key, the map is drawn over the cockpit image
so that you can see both the equipment displays and the map. Pressing
'Esc' again will hide the map. On the map, VOR stations are coloured
green and NDB stations are coloured red.

Interaction with the program is done thru the keyboard and the mouse.
Your aeroplane will continue straight and level flight until you give
it commands. Think of the aeroplane as one with an autopilot fitted
but one that lacks an FMC. You need to do the navigation but you don't
need to handle the plane as you do in a real world situation.

COMMANDS

Key 'Up Arrow'
	Increases speed.
Key 'Down Arrow'
	Decreases speed.
Key 't'
	Starts/stops the timer.
Key 'Left Arrow'
Key 'Right Arrow'
	Turns the aeroplane in the respective direction.
	The program will ask you how many degrees it should
	turn.
Key 'c'
	Clears the track made so far in the map.
Click on 'TO' in VOR display
	Switches the TO/FROM flag to TO.
Click on 'FROM' in VOR display
	Switches the TO/FROM flag to FROM.
Click on the middle dot in VOR display
	Selects the heading which centers the VOR needle,
	taking into account the TO/FROM flag.
Click on a heading in the compass rose of VOR display
	Selects the clicked heading.
Key '['
	Decreases time factor (if compiled with REALTIME)
Key ']'
	Increases time factor (if compiled with REALTIME)
Key 'q'
	Quits the program.

COMPILATION

You will only need the X11 libraries in order to compile the programs.
They don't depend on any other libraries.

First, edit the config.h file if you want the REALTIME option. The
program normally tries to draw 1000 frames per second and simulates 1
second of events between consecutive frames. If you enable the REALTIME
option, it draws 25 frames per second and simulates a number of seconds
of events between consecutive frames (called 'time factor'). This
number becomes controllable if you set REALTIME on.

After this, you will need to edit the Makefile and put proper paths
for X11 libraries.

When you are done editing the Makefile, just running 'make' will be
sufficient. You can put the executables 'fly' and 'holding' somewhere
in your path if you wish to remove the source tree. There are no other
files that need to be installed. 

THE PROGRAM 'holding'

This small program is designed as an exercise for studying holding
pattern entry methods. Only standard holding patterns are shown
because I like to decide on a method using the standard holding
pattern first, and then exchanging parallel and teardrop if the
pattern is nonstandard. Just try and see, there isn't much to it. As
with the program 'fly', the 'q' key exits  the program.

BUGS AND LIMITATIONS

* Time factor should not be greater than 20 when you are entering a
  turn. It will never stop turning if you do so.
* There are only 4 stations defined statically in the source code.
  There could be more and they could be both dynamically placed &
  selectable into the radio navigation equipment.
* It's just a weeks hack. I'm sure there are many bugs.

FINAL WORDS

The software is licenced under the GPL. Feel free to improve
upon it and redistribute it. If you have any questions, send an
email to cinarus@yahoo.com with subject 'About IFT'.

As a last warning, the program may have bugs. It has worked pretty
well for me, but it may not for you. Always check the results against
reality. You have been warned.

Enjoy your free flight simulator which can be run under a free OS.
And don't hesitate to create a full-featured one yourself.
