Updated: 09-Jan-2020
Turbojet developed in this country, using liquid hydrogen, varying its ramjet operation up to Mach 6. Experimental.
From appendix 7: The liquid hydrogen engine that is mentioned in the main text, has its operating scheme which is provided below.
"Supersonic Atrex LH2 engine"
Engines of ATREX
Model: Turbojet, hidrogeno

"Supersonic Atrex LH2 engine"