A310 rudder separation is possibly related to trapped moisture freezing
at altitude (i.e. expanding and leading to failure of the top rudder
hinge-bracket attachment point - which seems to be missing in the photos
- but is obvious from the photo below of an intact attached rudder. i.e.
that top hinge and the fin-mounted bracket departed with
theory there is that moisture is more likely to gather/be trapped at the
top of the rudder internally. Once the rudder hinge-bracket failed at
that topmost point, the upper part of the rudder would be somewhat
similar to a flag flying in a breeze. The resultant flail-induced
flutter would probably get out of sync with the induced upper fin-flutter
and the rudder's composite structure would rip away, from the top down.
Think of holding a sheet of paper at the bottom and 3/4ths of the way
up out of a car window at speed. The unrestrained 1/4 would tear away
if you were going fast enough.
there are also a number of applicable AD's (and who knows how many Service
Bulletins or Service Information Letters). See some of those reproduced
in part (with links) below the graphics.
A310 AD's (affecting rudders) -
Significance to Air Transat Rudder Loss
Directives; Airbus Model A300 B2 and B4 Series Airplanes;
A300 B4-600, B4-600R and F4-600R Series Airplanes, and Model
C4-605R Variant F Airplanes (Collectively Called A300-600);
and A310 Series Airplanes
(d) This AD was prompted by a decision by the FAA and a
civil airworthiness authority to require modification or
replacement of all affected parking brake operated valves
(PBOV). We are issuing this AD to
prevent loss of the yellow hydraulic system, which
provides all the hydraulics for certain spoilers; elements
of the hydraulics for flaps, stabilizer, pitch and yaw feel
systems, pitch and yaw autopilot, and yaw damper; and
elevator, rudder, and aileron.
effective date: 05 Apr 05
A300 B2 and B4 Series Airplanes (but
supersedes an existing airworthiness directive (AD) that
applies to all Airbus Model A300 B2 and B4 series airplanes.
The existing AD currently requires determining the part and
amendment number of the variable lever arm (VLA) of the
rudder control system to verify the parts were installed
using the correct standard, and corrective actions if
necessary. For certain VLAs, this new AD requires repetitive
inspections of the VLA and corrective action if necessary.
This new AD also provides a terminating action for the
repetitive inspections. Furthermore, this new AD reduces the
applicability of affected airplanes. The actions specified
by this AD are intended to prevent failure of both spring
boxes of certain VLAs due to corrosion damage,
which could result
in loss of rudder control and consequent reduced
controllability of the airplane.
further flight, do a detailed inspection of the VLA tie rod
for damage (bent or ruptured rod)
damage is found to the VLA or the rudder control system
during any inspection .......
effective date: 21 Mar 05
amendment adopts a new airworthiness directive (AD),
applicable to all Airbus Model A300, A300-600, and A310
series airplanes, that requires
to detect desynchronization of the rudder servo actuators,
and adjustment or replacement of the spring rods of the
rudder servo actuators, if necessary. For certain airplanes,
this AD also requires repetitive inspections to detect
cracking of the rudder attachments, and repair, if
necessary; or modification of the rudder attachments. This
proposal is prompted by issuance of mandatory continuing
airworthiness information by a foreign civil airworthiness
authority. The actions specified by the proposed AD are
intended to detect and correct
desynchronization of the rudder servo actuators,
which could result in
integrity of the rudder attachments and reduced
controllability of the airplane
(1) Conduct a
visual inspection, high frequency eddy current inspection,
or ultrasonic inspection, as applicable, to detect cracking
of the rudder attachments; and repeat the inspection
thereafter, as applicable, at the intervals specified in the
applicable service bulletin. Or
(2) Modify the rudder attachments to cold expand the rivet
Effective July 30, 1998.
of this AD is addressed in French airworthiness directive
96-242-208(B) R2, dated November 19, 1997.
amendment adopts a new airworthiness directive (AD) that is
applicable to all Airbus Model A300, A310, and A300-600
series airplanes. This action requires a one-time inspection
of the autopilot systems for proper engagement to determine
if the main electro valve electrical connectors of the yaw,
roll, and pitch autopilot actuators are correctly installed;
and corrective actions, if necessary. This amendment is
prompted by issuance of mandatory continuing airworthiness
information by a foreign civil airworthiness authority. The
actions specified in this AD are intended to prevent erratic
movements of the ailerons, elevator, and/or rudder that are
commanded by discrepant autopilot actuators, which could
result in reduced controllability of the airplane.
One operator of an Airbus Model
A300-600 reported high rudder forces and uncommanded rudder
inputs during final approach. The
inputs caused deflections of the rudder control surface
resulting in yawing of the airplane.
Investigation of the incident is ongoing, but preliminary
results indicate that failure of both
the main valve and the clutch valve of the autopilot yaw
actuator can lead to the actuator generating uncommanded
Effective August 24, 1999.
This is another
"post AA587" AD that applies to A310's as well (in addition to
the compendium of relevant AD's above)
AD/AB3/183 Vertical Stabiliser and Rudder
Applicability: All Model A300-600
and A310 aircraft, equipped with
post modification 4886
(composite) vertical stabilisers.
Requirement: Perform one-time detailed visual
inspections in accordance with DGAC Telegraphic
Compliance: Within 15 days after 28 November
2001, unless already accomplished.
This Airworthiness Directive becomes effective
on 28 November 2001.