Installation of Honeywell N1 Digital Electronic Engine Control (DEEC)

Installation of AlliedSignal Aerospace N1 Digital Electronic Engine Control (DEEC).

Installation of an AlliedSignal Engines TFE731-2C Turbofan Engine.

Installation of an AlliedSignal Digital Electronic Engine Control (DEEC).

Increase gross takeoff weight for Model 31 to the same as 31A and increase zero fuel weight from 13000 to 13500 for both Learjet Model 31 and Model 31A.

Replace engine inlet nose skins.

Install equipment racks (structural provisions only).

TR4000 thrust reversers installation.