From Appendix A1 / 6: An old industry founded in Zurich around 1805, EW. Specializing in water turbines, steam etc, they began with gas turbines in 1936 through its research department. They also made aircraft propellers.

-During the WWII, a Me-262 was confined in Switzerland and its engines were examined by Escher-Wyss, Sulzer and Brown-Boveri et Cie. Each one presented their projects later.

-In the case of EW, it was the ZTL, a double circuit engine which would later be called "by-pass". Of interesting design, although in fact there were at least three projects on the same basis with 1,500, 3,000 and 4,500 hp (?) of thrust.

"Escher-Wyss ZTL type"

-There were designs of a turboprop with 5000 CV of power to the shaft, towards 1945. There was even a 7500 CV twin version. Everything ended around 1947 and in 1969 it joined Sulzer to form a new high-tech company.

-At the NASM Museum in the USA, there is a documentation about a closed-circuit propulsion system, with references BE800400-01 and -02.