Junkers Ju 87 withstand dives of . The Jumo 211D in-line engine was installed, replacing the R-1s Jumo 211A. Due to an increase in overall weight by , the Ju 87 R-2 was slower than the Ju 87 B-1 and had a lower service ceiling. The Ju 87 R-2 had an increased range advantage of . The R-3 and R-4 were the last R variants developed. Only a few were built. The R-3 was an experimental tug for gliders and had an expanded radio system so the crew could communicate with the glider crew by way of the tow rope. The R-4 differed
Bristol Aeroplane Company Bristol Record Office include the papers of Lionel Harris, an engineer at the Bristol Aeroplane Company in the 1940s (Ref. 42794) (online catalogue) The Bristol Engine Company was originally a separate entity, Cosmos Engineering, formed from the pre-First World War automobile company Brazil-Straker. In 1917, Cosmos was asked to investigate air-cooled radial engines and, under Roy Fedden, produced what became the Cosmos Mercury, a 14-cylinder two-row (helical) radial, which they launched in 1918. This engine saw little use but the simpler nine-cylinder version known as the Bristol Jupiter was clearly a winning design. With the post-war rapid contraction of military