A Performance Diagnosis of the 1939 Heinkel He S3B Turbojet

The historical development of the world’s first pure jet propelled aircraft, the Heinkel He 178, and its turbojet the He S3B has been extensively documented, however only limited descriptions of the engine and component aero-thermo-dynamic performances have, as yet, been published in open English literature. The basic He S3B engine flowpath configuration of a radial compressor mounted back-to-back with a radial inflow turbine, intrigued the author as one excellent example of the pre WW11 radial turbomachinery ingenuity and expertise, to the extent that it prompted this diagnosis. Recognizing that some of the historically quoted HeS3B performance data may be dubious, attempts have been made to coalesce data from multiple sources into a more consistent account by conducting a detailed engine performance analysis. HeS3B engine performance characteristics are recreated based upon predicted meanline component maps derived from engine drawings and supporting data recently published by AIAA in his biography “Dr Hans von Ohain — Excellence in Flight”. Predicted engine performance parameters at both a five minute and maximum continuous rating are itemized, together with thrust/rpm/temperature variations at part speed conditions.