Honeywell Aerospace has been selected to provide its TFE731-2C turbofan upgrade and maintenance service plan for all 27 Learjet 35 aircraft of AirNet Express. The agreement is for 54 upgraded engines, plus spares and Honeywell's MSP service, for a total value of $70 million over the next decade. Key components in the $79,500 upgrade in an MSP Core Zone Inspection include a new cooled high-pressure turbine module for improved disk and blade life, new carbon ring seals, and an N1 digital electronic engine control for improved reliability, automatic recording of engine data, and better built-in test capability. Life improvements in the HP turbine disk will increase from 5,200 to 10,000 cycles, and HP turbine blade life from 3,000 to 9,000 hours. Upgraded engines will have a 2,100 hour major periodic inspection interval, which is a 50% improvement over existing ­2 engines.