Design Of The Low Vibration Turboprop Powerplant Suspension System for The DASH 7 Aircraft

Larger turboprop aircraft are finding increased acceptance with today's fuel-conscious operators. However, these aircraft must also appeal to the air traveller' who has become accustomed to the vibration free environment of turbojets. This requirement of minimum propeller-induced vibration results in a conflicting constraint for the designer of a flutter free installation.

Described in this paper is the two-plane engine mounting scheme used successfully in de Havilland's DASH 7 commuter aircraft. The suspension system meets the design objectives of low transmissibility, adequate whirl flutter margins and minimized landing loads.