MANUFACTURER: Bombardier Model CL-600-2B19
(Regional Jet Series 100 and 440) Airplanes SUBJECT: Airworthiness Directive AD 2009-10-05
SUMMARY: We are adopting a new
airworthiness directive (AD) for the products listed above. This AD
results from mandatory continuing airworthiness information (MCAI)
originated by an aviation authority of another country to identify
and correct an unsafe condition on an aviation product. The MCAI
describes the unsafe condition as:
A number of Flap Actuators with P/N [part number] 601R93101-21
and 601R93101-25 were identified as having pinion gears that did
not have acceptable certificates of conformance from the supplier.
This condition could result in flap failure.
Endurance testing conducted at Eaton Aerospace with
representative discrepant gears predicted a 3,000 flight cycle life
limit for the affected actuators. Fleet leaders with suspect
installed actuators are rapidly approaching this threshold. Failure
of the flap actuator pinion gear set could cause the right or left
inboard panel to disconnect, which could result in flap asymmetry
and consequent reduced controllability of the airplane. This AD
requires actions that are intended to address the unsafe condition
described in the MCAI.