You will have to use multiple parts, with the one(s) showing compression names c_gear, the parent to the steerable section of the wheel will be c_wheelsteer

Both c_wheelsteer and rudder02 work great. But now with regards to the main gear, do I have to use keyframe animation to show the compression (set no compression at frame 0 and full compression at frame 100?) I'm not quite sure about this, but I thought I saw something in some .AIR files that I've looked at about setting the compression of the landing gear.... ???

For clarification, ...

frame 0 is gear retracted
frame 100 is gear fully extended with suspension hanging
frame 200 is suspension fully compressed.

Frames 1-100 is used to animate gear extension/retraction.
Frames 100-200 is used to animate the suspension.

If your aircraft has significant travel from hanging to static compression (like a Dash 7 or Dash 8 with around 18"), please ensure that you model that kind of movement.  These aircraft will show a lot of compression when touching down or extension when on takeoff and liftoff.  It looks really nice to see this realism.

You must ensure that the contact points are set to match the animated movement for best results.  Around 70% of the total suspension movement is taken up on landing a Dash 7 from fully hanging to static compression.  About 4-6" remain once settled.  In this case, you have a high value for static compression and a lower one for max-static ratio.  This will give you the effects you are asking about.  See our Dash 7 and the Lockheed Constellation (freeware by John Howard White) as examples.

EDIT: Also, I believe the contact point information overrides the spring rate and suspension info in the air file.  However, I always fill out table 1004 spring loads for reference, or, just in case.

In contact points 1 and 2, you must set static compression (in feet) to equal the movement you want from hanging gear to static compression position with aircraft fully loaded.

Example:

You have animated gear movement in the model to 24" (frames 100-200).

In FS, you want 18" of that to be hanging gear to static compression movement and the remaining 6" to be available for hard touchdowns and suspension.

In contact points 1 and 2 for the main gear, static compression would be stated at 1.5' and max-static ratio stated at 1.333.  Set damping around .85 to start.  (do not overstate total movement)

Test with full load and then with minimum load adjusting vertical distance to ground and damping as required.

Try adding a Position key at 0, then a Position and Rotation key at 100, then a Rotation key at 200.  Then animate gear fully extended at 0 and 100, then move to 200 and compress the gear.

Before you restart your animation efforts, with gmax sitting at frame 0, delete all existing keys from the lower gear first.  Do that from frame 200 and work left to 100, etc.  Just click on the green bar in the time scale and press the Delete key.

In the aircraft.cfg Contact Point section, there is a contact point for each gear, center, left and right.  Typically, these are stated as contact points 0, 1, and 2.  Howeveryou should become familiar with each parameter in the statement as there is flexibility as to how they can be named.

See the AircraftContainer SDK for more details.

Thanks Kev.   Three years ago when I started the Dash 7 project, little was known about animation and modeling aircraft in gMax for FS.  Fortunately there were a few pioneers who blazed the trails and did the hard research and through trial and error came up with some basics.  A lot of credit must go to Chris File for his early tutorials in animation and lighting.

FSAlpha/FSEdge was instrumental in teaching me how to map and texture.  Finn Neuik's awesome videos really helped with other techniques.

These are the guys who were instrumental in my struggle and  understanding of these things.  I am deeply grateful for their early work.