MTV-27 aircraft propeller offering

The MTV-27 is a five-blade, constant-speed aircraft propeller from MT-Propeller of Atting, Germany, offered under supplemental type certificate for the M7 Aerospace SA226 and SA227 turboprop family. The model on the maker's page is the MTV-27-1-E-C-F-R(G)/CFRL250-103, fitted to aircraft with TPE331 engines in place of the original metal propeller.

The purpose of the propeller is to turn engine shaft power into thrust with lower vibration and noise. The blades carry a bonded nickel alloy leading edge for erosion protection. Blade life is stated as unlimited and the blades can be repaired after foreign object damage, which bears on maintenance planning and the cost of ownership for operators.

The key figures concern the effect on the aircraft. The five-blade design reduces ground roll by approximately 50 m (165 ft) and the take-off distance over a 50 ft obstacle by approximately 80 m (260 ft). Climb performance with two engines and with one engine is improved by up to 80 ft/min, and cruise speed by up to 2 kts. The propeller weighs approximately 20 lbs less than the original McCauley propeller and approximately 65 lbs less than the Dowty Rotol propeller. Aircraft noise falls by about 5 dB(A) against the original metal propellers, and cabin noise by 3 to 4 dB(A) depending on location.

For integration, no engine modification is needed, and the maker names no change to the cam or beta tube. The propeller is approved on SA226-T(B) and SA227-TT, -AC, -AT, -CC, -BC and -DC aircraft with the TPE331-10U, -11U, -12UA, -12UAR and -12UHR engines. Approvals are listed from the FAA, EASA, Transport Canada and the civil aviation authorities of Mexico, Venezuela and Brazil. The maker also notes more ground clearance, which reduces damage from foreign objects, and a start-up time reduced to one third, giving cooler ITT during engine start.

Typical applications are regional and commuter turboprop operations, freight and passenger, on SA226 and SA227 aircraft.