DENVER (AP) -- Federal investigators have returned to the charred wreckage of a Continental Airlines jetliner in search of clues about why the plane veered off a runway in Denver and skidded into a ravine.

The twin-engine Boeing 737-500 is sitting in a shallow, snow-covered ravine where it came to rest after its aborted take-off Saturday at Denver International Airport.

National Transportation Safety Board officials want to make use of scarce daylight hours today to examine the wreck, measure skid marks and then conduct their first interviews of the pilots.

Flight data and cockpit voice recorders were recovered and have been sent for examination to Washington, D.C. Investigators say both appear to be in good condition.

Federal Aviation Administration spokesman Ian Gregor says both the captain and the first officer had clean safety records. He declined to release their names.

The crash injured 38 people. Five people remained hospitalized as of last night.

Continental Airline's Flight 1404 attempted to take off for Houston around 6:20 p.m. Saturday.

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