Airworthiness Directives; Bombardier Inc. Airplanes

We are superseding an existing airworthiness directive (AD) for certain Bombardier Inc. Model CL-215-1A10 and CL-215-6B11 (CL-215T Variant) airplanes. That AD currently requires repetitive inspections to detect cracking of the lower cap of the wing front and rear spars at wing station (WS) 51.00, and the wing lower skin. Additional actions, if cracking is found, include reworking the lower cap of the front or rear spar, inspecting for cracking, and repairing any cracking. The existing AD also requires reporting inspection results. This new AD requires extending the inspection area of the rear spar lower cap from WS 51.00 to WS 49.50 and modifying the ultrasonic inspection calibration procedure. This AD was prompted by reports of cracking found outside the inspection area. We are issuing this AD to detect and correct cracking of the lower caps of the wing front and rear spars, and lower wing skin, which could result in reduced structural integrity of the airplane.