AD NUMBER: 2009-22-12

MANUFACTURER: Bombardier Model CL-600-2C10 (Regional Jet Series 700, 701 & 702) Airplanes, Model CL-600-2D15 (Regional Jet Series 705) Airplanes, and Model CL-600-2D24 (Regional Jet Series 900) Airplanes
SUBJECT: Airworthiness Directive 2009-22-12

SUMMARY: 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:

The heating capability of several [angle of attack] AOA transducer heating elements removed from in-service aircraft has been found to be below the minimum requirement. Also, it was discovered that a large number of AOA transducers repaired in an approved maintenance facility were not calibrated accurately.

Inaccurate calibration of the AOA transducer and/or degraded AOA transducer heating elements can result in early or late activation of the stall warning, stick shaker and stick pusher by the Stall Protection Computer (SPC).

FMI: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/0/B4808482CE875CE08625765E004BC6C7?OpenDocument