Duncan Aviation logo

Learjet MLG Strut Life Limit

January 2014

Presently, the Learjet* aircraft replacement requirement for the main landing gear (MLG) struts is set to either 9,000 or 12,000 landings, depending upon which cylinder is installed. Many operators have already reached or surpassed the 9,000 landing mark and have upgraded their struts to 12,000 landings or replaced them.

Recent revisions to the Learjet aircraft Chapter 5 Replacement Schedule now include IRN V32111101 for strut P/N 2394105 with a replacement interval of 16,500 landings. This strut is a modified unit of the strut originally installed.

This can be accomplished in two ways:

  1. Operators can purchase a previously upgraded strut, either new or overhauled
  2. Operators can upgrade their struts by installing the kit required by the applicable Service Bulletin, which contains a cylinder P/N 6041101 and other items to modify the strut.

The modification does not zero time the struts to allow for an additional 16,500 landings, but increases the current replacement interval to 16,500.

6000 Landing, Major LG Inspection

Please keep in mind that the 6000 landing, Major Landing Gear Inspection Requirements have not changed. This means that if struts are upgraded at the 12,000 landing mark, then the inspection will also be due at that time.

Always refer to the latest revision of the replacement schedule and bulletins as future revisions may negate any of the above.

Service Bulletin List

  • Learjet 23/24/25, Service Bulletin 32-7
  • Learjet 35/36, Service Bulletin 32-16
  • Learjet 31, Service Bulletin 32-11
  • Learjet 55, Service Bulletin 32-11


*Trademarks of Bombardier Inc. or its subsidiaries