Aircraft Service Manual
Jabiru Aircraft
Pty Ltd
JTM001-1
J120, J160, J170, J200/J400, J230/J430, J250/J450 Variants
REVISION
1
Dated: Nov 2011
Issued By: SW
Page: 45 of 233
4.17 SPECIAL INSPECTIONS
– CONTROL SURFACES
The following set of inspections have been developed to address potential control surface jamming.
These inspections are to be carried out at the frequency defined in the inspection chart of Section
4.3. In addition they must be repeated at any time when the control rigging may have been altered
–
i.e. if a control is removed, repaired or adjusted.
If the inspection shows that the aircraft requires adjustment Jabiru Aircraft or our local representative
must be consulted for an appropriate rectification method.
In Figure 10 several terms are defined. This is provided to clarify the statements given in the
remainder of this inspection.
Control
– This refers to control surfaces – rudder, elevator and ailerons.
Aircraft
– This refers to the fixed part of the aircraft immediately in front of the controls. In particular
it refers to the point indicated in Figure 10, where the control will hit the aircraft if a jam occurs.
Control at the point of overlap
– This is the particular point where the rearmost edge of the aircraft
is aligned with the front of the non-hinged side of the control. This is the critical point where a control
jam becomes possible. Any control which has a critical overlap of less than 2mm should also be
treated as having a “point of overlap” as defined by this bulletin.
Control clearance
– This is the working clearance between the control & the aircraft.
Control gap
– Best shown on Figure 12 (left). If the control passes the point of overlap a gap opens
between the aircraft and the control. A gap like this combined with excess flexing of the control
surface hinges will lead to control surface jamming.
Figure 10
– Normal and Jammed Control Illustration
4.17.1 INSPECTION A:
This inspection is to check if the controls are configured in such a way that there is a point of
overlap as shown in Figure 10. At noted above the point of overlap is the critical point at
which severe control jamming becomes possible.
-
Check each control by moving it to its maximum deflection and inspecting for a control gap
– as
shown in the example of Figure 12.
“Control at the point of
overlap” – rear edge of
aircraft lines up with the
front of the non-hinged side
of the control.
“Control” – in this
case an aileron
“Aircraft” – in
this case the
wing.
Jammed
control
–
excess hinge deflection
with the control at the
point of overlap results
in jamming.
“Control
clearance”
