By 1940 they had progressed to the point of having a semi-working prototype, which could not run under its own power and required an external supply of compressed air.

Müller and half of the existing Junkers team decamped and were happily accepted by Ernst Heinkel, who had started German jet development when he set up a lab for Hans von Ohain in 1937.

Helmut Schelp, who had taken over from Mauch, felt that the BMW 003 and Junkers Jumo 004 would reach production at about the same power levels long before either of the Heinkel projects would be ready, and cancelled both of them.

[1] Plans were also made for a turboprop version, the HeS 021, but the workload at Heinkel was so high that this project was later given to Daimler-Benz to complete.

The Spanish INI patented in 1951 a similar design (ES197663),[3] on exhibition at Cuatro Vientos Air Museum in Madrid.