11/30/2011. Remarks by Johan Visschedijk: "In 1932, shortly after the Praga engine concern opened an aircraft department, the company participated in a design contest for a new single-seat fighter organized by the Czechoslovak Defense Ministry. Designed by Pavel Bene and Miroslav Hajn, the CKD-Praga contender, the BH-44, was an exceptionally clean single-bay staggered biplane with wooden wings and a fabric-covered, welded steel-tube fuselage.
The first BH-44 prototype was powered by a 750 hp Praga ESV twelve-cylinder water-cooled engine and was flown on July 19, 1932. Although the ESV engine was supposed to afford 750 hp, it proved to give only some 500 hp. The second prototype flew from April 1934 with an ESVK engine, which, fitted with a compressor, was rated at 650 hp (this aircraft sometimes being referred to as the BH-144), but results remained unsatisfactory.
Proposals were made to fit the fighter with either the Gnome-Rhone Mistral 14K (BH-244) or Hispano-Suiza 12Ybrs (BH-344), but, in the event, the first prototype was re-engined with a 650 hp Rolls-Royce Kestrel VII with which it flew on October 30, 1934. The Kestrel performed poorly on the special fuel mix (BiBoLi) used by the Air Force (to which the BH-44 was known as the E-44) and the Avia B-34 was chosen as winning contender."