Garrett Aviation and General Electric (GE) are offering an upgrade to extend the overhaul life of the CJ610 turbojet that powers the Learjet 20-series business jet.
The spool rotor modernisation programme will increase the engine's time between overhauls from 5,000h to as much as 10,000h, potentially saving $85,000-$180,000 per aircraft.
The upgrade exchanges the CJ610's high-maintenance compressor for an eight-stage rotor assembly using improved materials. The design allows for individual blade replacement without rotor disassembly. The spool rotor is a "drop-in replacement", Garrett says, eliminating the cost and downtime of an engine overhaul.
Garrett and GE are looking at offering a similar modernisation for the CF700 aft-fan engine powering Dassault Falcon 20s, which uses the same core as the CJ610.
The spool rotor has been developed and qualified by GE Aircraft Engines under a USAir Force programme to modernise J85 turbojets powering Northrop T-38 trainers. GE is also developing a combustor liner with at least twice the inspection interval and ultimate life of the current component.
Garrett will begin taking delivery of spool rotors later this year. The GE-owned maintenance and modification company says about 400 Learjet 20-series aircraft are candidates for modernisation. Garrett is also offering to install a $125,000 Stage 3 hushkit for the CJ610 produced by Van Nuys, California, Aviation Equipment.
Source: Flight International
