Ohhhohohoho!
Welcome,
m'sieu, to the Salon des Modelistes: complex animations are the
specialité de la maison...
You have to decide what moves and how, and to decide which part will govern the animation of the whole.
From what I can see of the mechanism, the green sliding joint
1 does not rotate, just slides up and down, and will be the oleo section. Since the grey piece
2 at the bottom is bolted to the red arm, the two must move together and can only pivot back and forward a bit. The rudder-linked blue gear
3a pivots horizontally on the grey piece and the fork
3b pivots with it, possibly on the same axis. At the forward end of the red arm, the linking pieces must pivot forward and back a bit or the sliding oleo
1 would jam or buckle. And that's not considering how the fork springs will also move as the gear moves up and down and the tailwheel gear pivots...
How complex do you want it to be? Will it all be seen?
A preliminary hierarchy might be:-
grey oleo top
green sliding oleo
grey bottom piece
red arm
blue wheel fork
tailwheel
blue spring 1
blue spring 2
blue fork
linking pieces
You're going to learn a few new things if you go the whole hog: Look-At animation constraints will be needed building this. Muhahahahaaaa! (but I'll help if you do...)