Federal investigators say a twin-engine plane that crashed and burned at Southern California's Long Beach Airport last year was 653 pounds overweight and may have had water in its fuel tanks.

Five people were killed when the Beechcraft King Air turboprop crashed moments after takeoff in March 2011.

The National Transportation Safety Board hasn't yet determined the cause of the crash. The Los Angeles Times (http://lat.ms/KvAZ9b ) reports that NTSB documents show the plane was too heavy.

The documents also show a maintenance director believes popping sounds on takeoff may have been caused by water in fuel tank sumps. Sumps should be drained before each flight.

A plane maintenance director told the NTSB he didn't believe the fuel tanks had been regularly drained since the owner bought the plane in 2009.


Information from: Los Angeles Times, http://www.latimes.com