Jabiru J450 Constructors Manual
Pre-Paint>Fuselage>Wheel alignment
Tuesday, April 6, 2010
152 of 343
Pre-Paint>Fuselage>Wheel alignment
Objectives of this task:
To ensure that the main wheels are correctly aligned.
Overview:
Some aircraft have reported shuddering through the undercarriage and airframe on rotation or
landing. The amount of shuddering seems to be variable, depending on the all up weight of
the aircraft. Investigations on factory built aircraft have revealed that this phenomenon is
caused by a combination of two factors: toe-in or -out and the camber of the main wheels.
This procedure outlines how to check the wheel alignment and make the necessary
adjustments to correct the issue. It‟s a fairly basic technique, but we‟ve had success with it.
Procedure:
Firstly, a reference point is required from centerline (longitudinal axis) of the fuselage. This
can be achieved by dropping a plumb bob down from the tip of the spinner, and one from the
ventral fin and then, using a string line, join the two points. As seen in the picture below, we
have used the join line in the concrete slab as the reference line.
Place a straightedge (we‟ve found a length of box
section to be the best) along the outside wall of the
tire, and eyeball from above to check that both the
tire and the straight edge are parallel.