Hartzell Propeller has announced the availability of a new four-bladed propeller conversion for the Fairchild Metro II Airliner. The new prop is certified for all Fairchild (Swearingen) SA226-TC Metro II aircraft, except those with serial numbers S/N TC-398 through to TC-418. The new system replaces ageing original equipment three bladed propellers and is part of Hartzell’s ‘Top Prop’ performance propeller conversion programme.

A spokesperson said: “The primary goal of the system was a reduction in overall noise levels. Hartzell engineers were able to reduce the overall diameter of the prop by five inches, while improving or maintaining performance levels. This diameter reduction, along with careful application of advanced new airfoil configurations along the length of the blades, has achieved a very significant 10-12 dB (A) reduction in noise.

“Airport authorities report signif-icant improvement and satisfaction with the reduction in flyover noise, which has been a potential environmental issue for the Metro II especially in European operation.”

The system is expected to improve maintenance and operating costs through the reduction in propeller blade erosion, with the smaller diameter and subsequently greater ground clearance. In addition, the wide-chord blade design was developed to provide more generous blade repair limits than the standard three-blade prop.