Walter Riedel

Walter J H "Papa" Riedel ("Riedel I") (December 5, 1902–May 15, 1968) was a German-British engineer and rocket scientist who was the head of the Design Office of the Army Research Centre Peenemünde and the chief designer of the A4 (V-2) ballistic rocket. The crater Riedel on the Moon was named for both him and the unrelated German rocket pioneer Klaus Riedel.

Klaus Riedel ("Riedel II") and Walther Johannes Riedel ("Riedel III") were also Peenemünde engineers.

Biography At Heylandt Company beginning on 27 February 1928, Riedel was in December 1929 responsible for the development of liquid propellant rocket motors, and initially collaborated with Max Valier who had joined the company at that date. Riedel took over full responsibility for the rocket motor development in 1930, after Valier's untimely death following a rocket motor explosion during a test using paraffin oil (kerosene) as fuel instead of ethyl alcohol. Along with Walter Dornberger, plans were drawn up for a more suitable and better equipped test site for large rockets at Peememünde, to take the place of the rather confined Kummersdorf. From 17 May 1937, following the transfer of the rocket activities from Kummersdorf to the Army's new rocket establishment at Peenemünde, Riedel headed the Technical Design Office as chief designer of the A4 (V2) ballistic rocket The site consisted of a system of galleries driven into the mountains, and received the code name Zement (Cement). Work on the site started at the beginning of 1944 and was intended to be completed in October 1945. From 1 October 1943, Riedel was responsible for supervising the transfer, to Ebensee, of the Peenemünde development facility.

From 29 May 1945 to 20 September 1945, following the end of World War II, Riedel was held in protective custody (Sicherheitshaft) at the US Third Army's internment camp at Deggendorf, situated between Regensburg and Passau.

Riedel died while visiting East Berlin in East Germany.