AD 2015-12-06 Airworthiness Directives; Learjet Inc. Airplanes

Models named: 45. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to Learjet Inc. Model 45 airplanes, certificated in any category, as identified in Bombardier Recommended Service Bulletin 40-56-03, Revision 1, dated October 15, 2012 (for airplanes having serial numbers (S/Ns) 45-2000 through 45-2120 inclusive, and S/Ns 45-2122 through 45-2130 inclusive); and Bombardier Recommended Service Bulletin 45-56-3, Revision 1, dated October 15, 2012 (for airplanes having S/Ns 45-005 through 45-427 inclusive).

Comply with this AD within the compliance times specified, unless already done.

Within 600 flight hours or 36 months after the effective date of this AD, whichever occurs first: Do the inspections specified in paragraphs (g)(1) through (g)(3) of this AD. Do all inspections and corrective actions specified in paragraphs (g)(1) through (g)(3) of this AD, in accordance with the Accomplishment Instructions of Bombardier Recommended Service Bulletin 40-56-03, Revision 1, dated October 15, 2012 (for airplanes having S/Ns 45-2000 through 45-2120 inclusive, and 45-2122 through 45-2130 inclusive); or Bombardier Recommended Service Bulletin 45-56-3, Revision 1, dated October 15, 2012 (for airplanes having S/Ns 45-005 through 45-427 inclusive). (1) Do a general visual inspection of the coupe rails to detect gouging and scratches and to determine whether a radius has been removed or damaged. (i) If gouging or scratches are found, before further flight, burnish or blend the gouges and scratches. (ii) If the radius has been removed or damaged, before further flight, restore the radius. (2) Do an ultrasound inspection to measure the dimensions of the lower coupe rails. (i) If the coupe rail has an “X” dimension of 0.246 (6.248 millimeters (mm)) or greater, and a “Y” dimension of 0.148 (3.759 mm) or greater: Before further flight, identify the coupe rail, in accordance with table 1 of Bombardier Recommended Service Bulletin 40-56-03, Revision 1, dated October 15, 2012 (for airplanes having S/Ns 45-2000 through 45-2120 inclusive, and S/Ns 45- 2122 through 45-2130 inclusive); or Bombardier Recommended Service Bulletin 45-56-3, Revision 1, dated October 15, 2012 (for airplanes having S/Ns 45-005 through 45-427 inclusive). (ii) If the coupe rail has an “X” dimension between 0.246 (6.248 mm) and 0.166 (4.216 mm) or a “Y” dimension between 0.148 (3.759 mm) and 0.134 (3.403 mm): Before further flight, identify the coupe rail, in accordance with table 2 of Bombardier Recommended Service Bulletin 40-56-03, Revision 1, dated October 15, 2012 (for airplanes having S/Ns 45-2000 through 45-2120 inclusive, and S/Ns 45- 2122 through 45-2130 inclusive); or Bombardier Recommended Service Bulletin 45-56-3, Revision 1, dated October 15, 2012 (for airplanes having S/Ns 45-005 through 45-427 inclusive). (iii) If any coupe rail “X” dimension is below 0.166 (4.216 mm) or “Y” dimension is below 0.134 (3.403 mm): Before further flight, replace that coupe rail with a new coupe rail. (3) Do a flange and radius eddy current inspection for cracks of the left-hand and right-hand lower coupe rails. (i) If no crack is found, before further flight, mark the new data plate. (ii) If any crack is found, before further flight, replace the coupe rail with a new coupe rail.

This AD was prompted by reports of non-conforming windshield supports (coupe rails). We are issuing this AD to detect and correct non-conforming windshield supports, which could result in uncontrolled cabin depressurization, and compromise of the capability of the windshield to withstand a bird strike.

None.