Low Cost Jet Fuel Starter

This paper presents the results of a design study of a low cost Jet Fuel Starter (JFS). The JFS is a small free turbine turboshaft engine with a peak output of 150 horsepower. The design concentrates on high output per unit volume and weight, and on low cost. A low speed, four stage axial compressor design results in a compact, lightweight starter. Die castings and a radial pin construction for both the static structure and the compressor rotor provide the most significant cost savings over conventional gas turbine fabrication methods. The low speed concentric shaft design (approximately 70 percent of usual design practice) permits a simple two bearing shaft suspension for both rotors. The resulting close coupling of the turbines reduces the number of expensive hot end components to only five parts.