March 2013

March Calendar 2013MBB B0105 HGH
Winged-Compound Helicopter
250 miles/hour (218 knots): March 4, 1975

The Hochgeschwindigkeitshubschrauber (HGH, or "High Speed Helicopter") was a program that used a Messerschmitt-Bölkow-Blohm (MBB) Bo105 V-4 (registration D-HAPE) to test high speed attributes. Various configurations were tried, with the 6.2 m spanwidth winged compound helicopter reaching 404 km/h (224 knots) in a dive flight condition on March 4, 1975. The pilot was Siegfried Hoffmann and the flight test engineer was Adam Teleki. The hub was faired with an elliptical body, the landing skids re-designed for low drag and the fuselage aft body modified for less flow separation, looking similar to the BK117. The rotor blade tips encountered Mach 0.97 on the advancing side. The program was stopped after the Ministry of Defense lost interest in high speed helicopters. Since 1980, it is on display at the Deutsches Museum in Munich, Germany.

By Berend G. van der Wall

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