The MCSK100 Service Kit is an STC-FAA-PMA kit that replaces the Cessna parts at the aft wide flap roller location to prevent flap support arm wear.

Wear on the flap support arms is caused by the flap rollers due to the asymmetric extension or retraction of the flap during flight. This asymmetry is caused by the inboard or outboard section of the flap leading during the retraction or extension of the flap. Many factors, including rusty or damaged rollers or flap track imperfections, can contribute to this condition. This asymmetry causes the rollers to be pressed against the flap support arms (roller end loading), which, over time, causes damage to the flap support arms and structurally weakens the flap. Cessna Service Bulletin SEB95-3 REV. 1 addresses this issue by calling for the inspection and repair or replacement of the support arms and rollers. SEB95-3 REV. 1 also requires the installation of stainless steel washers on each side of the forward rollers to reduce the wear between the roller and the support arms. SEB95-3 REV. 1, however, did not offer a preventative solution to the wear problem experienced at the aft roller locations. McFarlane Service Kit MCSK100 is a permanent solution to the wear problem at the aft roller locations and it costs about the same as the factory parts.

It is important that the Cessna Service Bulletin SEB95-3 REV. 1 is fully complied with before the MCSK100 Service Kit is installed. A copy of this Service Bulletin is available from McFarlane. Installation of the McFarlane MCSK100 Service Kit (s) is considered a minor alteration and does not require the filing of FAA Form 337. An entry in the aircraft maintenance records shall be made by appropriately rated aircraft maintenance personnel upon completion of the service kit installation.