Document ID: chunk:federal_register_of_legislation:F2006B09243:body:0:p2
Version: federal_register_of_legislation:F2006B09243
Segment Type: other
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Character Range: 2631–5155

the above- referenced ASB.

7.        If gram gauge reading from the repeat AOA sensor vane movement test is between 110 and 170 grams, replace the AOA sensor in accordance with the above-referenced ASB.

Bombardier (Boeing Canada/de Havilland) DHC-8 Series Aeroplanes

 AD/DHC-8/84 (continued)

8.        Pre-Mod 'J' status AOA sensor (P/N 861CAB) may not be installed on any aircraft.

           Note: Transport Canada CF-2001-46 refers.

           Compliance:  For Requirement 1 - Initially, prior to 1000 hours time in service (TIS), or 6 months whichever occurs first, after the effective date of this Directive.

           For Requirement 2 - Before further flight, immediately following Requirement 1. For Requirement 3 - Within five days after completing the Requirement 2 test.
           For Requirement 4 - Within 1000 hours TIS or six months, whichever occurs first, from the date of the Requirement 2 test.

           For Requirement 5 - Prior to accumulating 5000 hours TIS or 24 months, whichever occurs first, from the date of the initial Requirement 2 test.

           For Requirement 6 - Within five days after completing the Requirement 5 repeat test.

           For Requirement 7 - Within 1000 hours TIS or six months, whichever occurs first, from the date of the Requirement 5 repeat test.

           For Requirement 8 - As of the effective date of this Directive.

           This Airworthiness Directive becomes effective on 21 February 2002.

           Background: The manufacturer of the AOA vane has determined that viscous damper leakage in some vanes can cause the vane to stick against the upper or the lower vane travel stop.

           Although no problems with sticking AOA vanes have been reported on the DHC-8 aircraft, a sticking vane would provide the stall warning system with an incorrect angle of attack reading. This would be expected to occur at airspeeds below approximately 110 kts. Above 110 kts, the airflow would unstick the vane.

Bombardier (Boeing Canada/de Havilland) DHC-8 Series Aeroplanes

 AD/DHC-8/84 (continued)

           This Directive requires an initial inspection to determine the modification status of the AOA sensors and, if necessary, a sensor vane movement test together with the replacement of any sensor vane that fails the test.

 Eugene Paul Holzapfel
 Delegate of the Civil Aviation Safety Authority 14 January 2002

 The above AD is notified in the Commonwealth of Australia Gazette on 30 January 2002.