PENN TWP — The Federal Aviation Administration is investigating the crash of a small plane that slid off the runway at the Butler County Airport late Monday afternoon.

The pilot, 60-year-old Safdar Khwaja of Murrysville, was not injured.

The Cessna 340A twin-engine aircraft was in the process of taking off just before 5:20 p.m. when Khwaja experienced engine trouble.

Airport manager Roy Uptegraff said Khwaja tried to abort the takeoff due to an engine problem, but the plane skidded off the right side of the wet runway and over a hill.

“By the time (the pilot) reacted to the trouble, it was too late, he ran out of runway,” said an official for AirQuest Aviation, the airport’s fixed-base operator, who requested anonymity.

The plane, which was headed west, left skid marks over the last one-third of the 4,801-foot runway, Uptegraff said.

“That indicates it was a high-speed abort,” he said. “The plane had a pretty good velocity going.”

The light rain that fell on the runway and the still frozen and hard ground at the end of the runway likely made for difficult braking, the official said.

Uptegraff admitted he was amazed that the plane did not hit any of the approach end lights.

“It was lady luck,” Uptegraff said. “He missed every light out there and there’s a row of them.

Khwaja called AirQuest and asked for help in getting the damaged plane out of its predicament.

“We told him we couldn’t because this was considered an accident,” said the AirQuest officials. “We called 911.”

The Penn Township Volunteer Fire Department and Butler Ambulance Service were sent. Penn Township police also were notified and monitored the situation, said police officer Cheryl Cranmer.

Members of Civil Air Patrol Composite Squadron 712, which is headquartered at the airport, by chance were on site for the group’s weekly Monday night meeting and were alerted.

“We just happened to be here,” said Major Keith McMillen, “but we were not dispatched because this was being handled as an accident at the airport. Local EMS and the Penn Township fire department were notified.”

Uptegraff said some fuel leaked from a crack in at least one of the plane’s fuel tanks, but there was no fire and emergency crews hosed down the aircraft.

The runway was closed but reopened around 8 p.m.

The plane’s registration number matches that of a fixed wing Cessna 340A registered to Seven Sierra Yankee LLC in Monroeville, Allegheny County, according to FAA airplane registration records.

Khwaja, who is listed as a principal of the aircraft leasing and operations company, did not return a telephone call Monday night.

The plane, which was built in 1979 and has a Continental TSIO-520 series engine, was issued its registration certificate in 2012, the FAA registry says.

Uptegraff said Khwaja houses that plane at the airport’s community hangar. He keeps a smaller plane at the airport’s T-hangar.

The extent of the Cessna 340A’s damage was not immediately known. But the AirQuest official did not sound optimistic.

“It’s probably a total loss,” he said. “Once the (propellers) hit the ground, it’s gone.”

Uptegraff agreed and noted that the plane’s propellers were bent and the nose gear was ripped off in the crash.

A representative from the FAA was to examine the plane by today. But an agency spokesman Monday said he could not provide any additional information until the investigation was complete.

A timetable for the investigation was not available.