Unalaska, AK – Federal authorities are investigating what led a Pen Air plane to crash on its landing on the Unalaska Airport runway yesterday afternoon.

The Grumman Goose was returning on a charter flight from Akutan at about 4:30 p.m. when it clipped a tractor trailer on Ballyhoo Road, then crashed on the runway. The pilot and the eight passengers onboard the amphibious plane at the time have not yet been identified, but emergency room staff at the Iliuliuk Health Clinic said that all nine of them were treated for only minor injuries and released. The driver of the truck had either minor injuries or none at all, according to Public Safety Department Sgt. Jennifer Shockley.

The National Transportation Safety Board and Federal Aviation Administration are both investigating what happened. NTSB air safety investigator Clint Johnson said his agency began that work this morning.

"What we're in the process of doing right now is interviewing company personnel with Pen Air and also the airport folks to find out exactly what the chain of events [was]," he said.

The big question is whether Pen Air had properly closed off Ballyhoo Road to traffic as the plane approached. Because of the odd location and short length of the Unalaska Airport's runway, approaching planes have to fly low over a section of the road connecting the city to the Port of Dutch Harbor as they land. The airline uses a van and flashing lights to keep vehicles out of harms way.

The plane was lifted off the runway with a crane from Pacific Stevedoring at about 7 p.m. It looked to have sustained significant damage, with much of the cockpit crushed and parts of the tail, landing gear and boatlike hull badly battered as well.

Local Pen Air personnel referred all questions to the company's Anchorage offices, where representatives have been unavailable for comment today.