Development Technology for a Stepped Diameter TMC Shaft

This proposal is to develop and demonstrate technologies for a JSF TMC shaft. Two possible JSF TMC shaft configurations are possible. One is a large diameter, thick wall, very high torque, bottle shaped LP shaft that transmits torque from the LP turbine to both the engine’s fan and an in-line lift-fan-shaft. The other is a stepped configuration inner shaft of a counter rotating engine-system. The first is for use in a lighter weight design of the current JSF engine and the second for use in a redesigned, significantly lighter weight, counter rotating JSF engine. A Phase I SBIR is studying design and manufacturing approaches applicable to the forward and aft ends of a TMC stepped shaft for the JSF engine and the GE/VAATE counter-rotating engine. Issues associated with using TMCs for a very high torque, thick walled, application are being successfully addressed under a Phase II SBIR program titled “Thick-Wall Oriented-Fiber TMC Shaft Development”. This proposal is for a Phase II follow-on to the above Phase I TMC Stepped Shaft Program. It will provide detailed analytical derivations, scale-up-development and prototypical device demonstrations, as well as develop a technology transition plan for future systems and commercial ventures.