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Learjet 45: 10-Year Spindle Life Limit

February 2011

Lear 45 operators approaching the 10-year life limit of the spindle (P/N 4527102103-001) have two options, to replace the spindle or the spindle assembly. Each option has its benefits and drawbacks.

Spindle Replacement

This is accomplished via SB45-27-36 or SB40-27-20, as applicable, and requires machining the spindle. Machining will increase the downtime especially if the spindle is shipped out to a vendor for the machining work. 

Spindle Assembly Replacement

Replacing the spindle assembly (P/N 4527102095-009) accomplishes both the SB and life-limit requirements. The -009 assembly is more expensive than just the spindle, but it does not require the added downtime for machining. The mechanic can go from removal straight to installation of the new part without any intervening steps.

Learjet Technical Support

Jerry Cable
Cable, Jerry - Accessory Tech Rep - Lincoln, NE (LNK). Aviation professional since 1991.

Airframes: Astra, Challenger, Citation, Embraer, Falcon, Gulfstream, Hawker, Learjet, King Air, Global, Westwind

Hydraulic equipment and pumps, Pneumatic valves, Wheel and Brake, Emergency Power Supplies, Electric Motors, Mechanical Actuators, Landing Gear and Accessory Components and Systems Specialist.

Direct: +1 402.479.8112
Mobile: +1 402.202.6785


LOUBC Cary Loubert Airframe Tech Rep Challenger, Global, Learjet Battle Creek, MI (BTL) +1 269.969.8452