Document ID: chunk:federal_register_of_legislation:F2009L02774:body:0:p4
Version: federal_register_of_legislation:F2009L02774
Segment Type: other
Provision Reference: 
Character Range: 8511–11506

the above-specified ADGs back onto the same aircraft if it has been removed for non-related purposes, such as for maintenance or to gain access to other components, etc.

             Note 10:  The CL-604 Illustrated Parts Catalog also specifies that, for an ADG with a Hamilton Sundstrand P/N in the 761339 series, future procurement is to be an ADG with Hamilton Sundstrand P/N 1711405.

                Note 11:  Transport Canada AD CF-2009-24 dated 19 May 2009 refers.
Compliance:  For Requirement 1 - Within 400 flight hours (FH) or before the next scheduled ADG operational test, whichever comes first, after the effective date of this AD, unless already accomplished and the ADG has not subsequently been replaced.

             For Requirement 2 - Within 400 FH or before the next scheduled ADG operational test, whichever comes first, after the effective date of this AD, unless already accomplished.

             For Requirement 3 - Before further flight after each scheduled ADG operational test.

             For Requirement 4a - Before further flight after each unscheduled in-flight ADG deployment.

             For Requirement 4b - Within 72 hours or 10 hours air-time, whichever comes first, after each unscheduled in-flight ADG deployment.

             For Requirement 5 - Before further flight following each unscheduled on-ground ADG deployment task.

             For Requirement 6 - Within 400 FH or before the next scheduled operational test, whichever comes first, after the effective date of this AD.

             For Requirement 7 - From the effective date of this AD.
             This Airworthiness Directive becomes effective on 30 July 2009.
Background:  Two cases of a crack on a "dry" ADG (Hamilton Sundstrand part number in the 761339 series), in the aft area of the strut and generator housing assembly, have been reported on CL-600-2B19 aircraft.  The same P/N is also installed on CL-600-2B16 (CL-604) aircraft.  Investigation determined that the crack was in an area of the strut where the wall thickness of the casting was below specification, due to a manufacturing anomaly in a specific batch of ADGs.  Structural failure and departure of the ADG during deployment could possibly result in damage to the aircraft structure.  If deployment were activated by a dual engine shutdown, ADG structural failure would also result in loss of hydraulics for the flight controls.

             This AD gives instructions to check the P/N of the installed ADG and, for ADGs with a P/N in the 761339 series; the S/Ns of the ADG and the strut and generator housing assembly are also to be checked.  If these serial numbers are within specified ranges initial and subsequent repeat fluorescent penetrant inspections of the ADG strut are required.

   This AD also gives instructions to perform a fluorescent penetrant inspection after each unscheduled in-flight ADG deployment and a visual inspection after each unscheduled on-ground ADG deployment.