SR-57 Buzzard • wp.archivoaereo.com

In the mid-1950s, the West German Air Force command began to show interest in inexpensive training aircraft for initial pilot instruction. Military engineer Alfons Pützer decided to develop such an aircraft to meet this requirement.

In 1958, Pützer developed the SR-57 Buzzard project, a two-seater low-wing monoplane powered by a 95-hp Continental C90-12F engine with a pusher propeller. After researching the tail section of his previous aircraft, the Dohle, Pützer, in collaboration with Walter Horten, decided to use a V-tail to reduce power loss.

Table of Contents

SR-57 Buzzard Design and First Flight

The aircraft prototype, with registration number D-EHIV, made its first flight in February 1959. During testing, the aircraft demonstrated satisfactory flight characteristics. However, after the West German Air Force adopted the French jet trainer Fouga Magister, the military revised its views on piston-engine aircraft.

As a result, the DVL (Deutsche Versuchsanstalt für Luftfahrt) reclassified the Buzzard project as experimental. In the same year, Alfons Pützer offered his aircraft to another German engineer, Erich Ufer, who was developing an annular tail for Bölkow GmbH, for the purpose of testing the design.

From Trainer to Experimental Aircraft

For these experiments, the SR-57 prototype was reconfigured in late 1960 into the SR-57-2k, featuring this unusual tail section. The modified aircraft’s first flight took place on July 12, 1961. After three months of testing, good results were obtained, but work was again discontinued in 1964.

Subsequently, the Buzzard was transferred to the Karl Lürenbaum Institute for Engine Dynamics in Aachen for testing turbofan engines, alongside the experimental Rhein-Flugzeugbau RF-1 aircraft.

Further Modifications and Final Legacy

In 1971, the Buzzard was modified again; this time, Walter Horten redesigned the aircraft, installing a conventional tail and replacing the pusher propeller with a tractor one. After this final overhaul, the SR-57 flew for several more years until it was lost in a hangar fire.

Technical Specifications

Modification	SR-57
Wingspan, m	12.00
Length, m	6.30
Height, m	2.20
Wing area, m2	18.00
Empty weight	600
Normal takeoff weight	760
Engine type	1 Piston engine Continental C90-12F
Power, hp	1 x 95
Maximum speed, km/h	200
Cruising speed, km/h	180
Crew, crew members	2