Stiffener, Flap Trailing Edge

Flap Trailing Edge Stiffener for Cessna Aircraft

New streamline shape and improved fit to reduce stress cracks. 
FAA-PMA Stiffener made of 6061 T6 Aluminum material. 

Logbook entry is all that is required.

What is the purpose of a flap trailing edge stiffener?

• Reinforce the flap trailing edge to make it more resilient to hangar rash.
• Ensure a straight trailing edge. Without a stiffener, the trailing edge tends to have a "wavy" appearance where the top and bottom skin rivet together.
• Reduce stress in the flap skins and prevent cracks around the rivets. Without a stiffener of the proper shape, the skin must abruptly bend where the top and bottom skins rivet together.
• Provide a blunt surface, thus preventing diamond shaped cut patterns on the foreheads of pilots and passengers.

McFarlane's stiffeners are streamlined and have the correct angle.

Original stiffeners deform the skins, resulting in cracks, strain in the corrugation, and stress around the rivet heads.

Early airplanes did not have a stiffener, but it can be added.

New Improved Fit to Reduce Skin Stress

Our new McFarlane stiffeners are accurately shaped to the same angle that the top and bottom skins come together to completely eliminate the bending stress due to riveting the skins together. This prevents stress concentration in the skin corrugations and near the rivets making cracks less likely. McFarlane has improved the stiff ener angle as compared to other brand of triangle stiffeners.

New Streamline Shape
Our new design smoothly transitions from the skin surface to a blunt trailing edge without an unsightly bulb and resultant drag found on common trailing edge stiffeners. The new shape even weighs less than other bulky stiffeners.

Instructions for Continued Airworthiness