
Jabiru J450 Constructors Manual
Pre-Paint>Fuselage>Undercarriage>Assemble main gear
Tuesday, April 6, 2010
34 of 343
Pre-Paint>Fuselage>Undercarriage>Assemble main gear
Objectives of this task:
In this task you will assemble the main undercarriage legs, which includes fitting the axles,
disc brakes and wheels and adjusting the brakes.
Materials required:
Cards # J8 „
Dual Brakes
‟ and J21 „
Main wheels
‟
Brake fluid for assembly of disc brake pistons
Spat brackets
Fit the retained nuts to the spat mounting brackets
using countersunk 3/32” rivets. There are 4 retained
nuts (arrowed) on each bracket. Countersink the
actual screw holes where the spat will be fitted: the
countersinks will help to guide the screws into the
holes when fitting the spats.
Fit the axles and backing plates
Slip the stub axles (from the „
Main wheels
‟
card) through the brake mounting plate (photo
at right) and fit to the main gear leg. The
chamfered face of the plate is on the side that
faces the gear leg.
Align the bolt hole in the outboard end of the
stub axle vertically and fix the plate in place 2
x AN5-16A bolts at the top and 2 x AN5-15A
bolts at the bottom. The longer bolts are used
at the top to allow for the spat bracket.
Fit the spat bracket to the AN5 bolts with the
captive nuts facing towards the wheel and with
the notched surface to the bottom. Fix with one
Nyloc nut and washer as shown at right.
Check that the hole in the outboard end of the
stub axle is positioned up and down before
tightening the nuts up.
Fit Nyloc nuts and washers to the 2 bottom
bolts and a Nyloc nut with a penny washer to
cover the adjustable slot at the top rear bolt.
This slot will allow the spat to be moved up or
down during final assembly.
The location of the slot determines if this is a
right or left leg – the slot must face the rear of
the aircraft. The gear leg in the photo above is a left-hand gear leg.
Use a permanent marker to identify each leg as being either a right or left leg at this point – it
can save confusion when you come to fit the gear legs in the next task.
Front of aircraft