PERRIS, Calif. (AP) _ A skydivers' plane that crashed shortly after takeoff, killing 16, was loaded with contaminated fuel that caused the engine to falter, a newspaper reported.

The contamination was traced to a load of fuel delivered to Perris Valley Airport on Saturday, Don Llorente of the National Transportation Safety Board said Friday.

Laboratory tests should identify the contaminant by Monday.

The plane's engines ''don't run on that substance,'' Llorente said in today's Press-Enterprise of Riverside.

Ben Conatser of Canyon Lake, who owns airport and the plane that crashed, said the pumping equipment used to put the fuel into a truck used to refuel planes had been used to pump other liquids and wasn't purged before it was used to transfer the aviation fuel.

In addition, the NTSB found that the pilot and copilot, both of whom died in the crash along with 14 parachutists, had no formal training in flying the De Havilland DHC-6 Twin Otter plane, he said.

The plane can be difficult to handle if the engine malfunctions, Llorente said.

The twin-engine plane went down nose-first Wednesday while carrying 20 members of American and Dutch skydiving teams and the pilots. Six survivors remained hospitalized Friday.

On Thursday the NTSB said none of the parachutists was wearing safety belts and the pilot and copilot were not properly restrained - factors that may have contributed to the high death toll.

Witnesses reported hearing an engine problem when the plane took off.

The airport is an internationally known center for skydiving in rural Riverside County, 70 miles southeast of Los Angeles.