The 10,000th Bonanza came off the production line in February 1977, but five years later, Beech discontinued production of the V-tail Bonanza to concentrate solely on the straight-tail Bonanza. Concerns over the safety of the V-tail design (and the resultant liability) undoubtedly played a major role in that decision. Independent studies found that the V-tail Bonanza had a fatal in-flight failure rate 24 times higher than the straight-tail version; a possible cause is the greater stress placed on the V-tail aircraft's tail and fuselage during pitch and yaw manoeuvres than on the straight-tail version. All Bonanzas of Lufthansa Flight Training are - like seen on the image above - of the type F33A, featuring the straight-tail design.