An Ohio man was critically injured Wednesday when the semitrailer truck he was riding in crashed in Parleys Canyon.

Willie F. Jones, 37, Cincinnati, Ohio, was riding in the sleeper compartment of a westbound truck driven by Willie L. Gilmore, 31, also of Cincinnati.The truck, loaded with household goods, was being downshifted about 9:55 a.m. when the gears got stuck in neutral, causing the truck to "freewheel," said Utah Highway Patrol Trooper Stan Parkin.

Gilmore steered the truck down the East Canyon turnoff, went across the road and tried to head up the on-ramp but was unable to make a turn and struck a parked trailer on which a racing car was loaded, Parkin said.

The truck then plunged 50 feet down an embankment and crashed in a jack-knife position. Jones was thrown clear.

"When we arrived, he (Jones) was face down in the dirt with big, gaping wounds in the back," said Parkin. Both men were flown to University Hospital, where Jones was in serious but stable condition in the intensive care unit and Gilmore was in serious condition Thursday.

The racing car and trailer, owned by Flip's Speed Shop, Yonkers, N.Y., sustained about $200,000 damage. The $500,000 semitrailer rig was destroyed, Parkin said.