Piston Wrist Pin Ejected From A Cessna 172 Made A Hole In A Roof

On a checkout flight with a newly-licensed pilot, flight instructor Rick Eason, a faculty advisor for the University Flying Club in Orono, ME, was forced to make an emergency landing after there was a loud bang under the cowling of the club-owned Cessna 172 and the plane started shaking.

The landing at Bangor International Airport was successful, but Eason was contacted by the control tower and asked if something had been "lost" from the airplane.

The Bangor Daily News reports that yes, something did come off the airplane. A wrist pin ... which connects the piston head to the arm inside the cylinder ... separated and was ejected from the airplane. The four-inch metal rod (pictured above) was reportedly still hot when it was discovered by a homeowner, who had a newly-minted hole in his roof and front-room ceiling (pictured below) where the part came through.

No one in the home was hurt, but authorities estimate that the part caused about $5,000 damage to the house.

The flying club's mechanical officer Soren Hansen said one of the pistons in the Skyhawk split in half. "We don't know why it happened," Hansen told the paper.

The incident reduced the available airplanes in the flying club's fleet by 50 percent. Hansen said the 172 was "probably" getting close to time for a major overhaul. The engine reportedly had about 1,500 hours SMOH on a TBO of 1,800 hours. (Images courtesy Bangor, ME, Fire Department)

FMI:  www.ntsb.gov