Learjet: Airworthiness Directive Deadline Approaching for Learjet 60* Aircraft

May 2014

August 5, 2014, is the deadline for Airworthiness Directive (AD) 2013-13-09.

The FAA issued this AD requiring up to four different Service Bulletins (SB) be installed, depending on aircraft serial number. The following are the SBs and a brief explanation of each. 

  • SB 60-27-6 installs a wheel speed detect box to allow spoiler deployment when the main wheels are spinning to simulate a squat switch input.
  • SB 60-32-33 & SB 60-57-7 install metal shielding around the main landing gear (MLG) squat switches & MLG anti-skid valves to protect these items in case of an accidental impact.
  • SB 60-78-7 installs a thrust reverser (TR) interface box that works in conjunction with the wheel speed detect box to allow TR deployment with the main wheels spinning in lieu of squat switch input.

You need to check the affectivity of each of these SBs to verify which ones may still need to be complied with. Some of these SBs may have been complied with previously.

As per any Terminating Action on an AD, revision levels have to be verified for compliance.$FILE/2013-13-09.pdf

*Trademarks of Bombardier Inc. or its subsidiaries


Dave Schiver Airframe Tech Rep Challenger, Global, Learjet Lincoln, NE (LNK) +1 402.479.1680

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