All lanes of the 14th Street bridge will be open for the morning rush hour today for the first time since the Air Florida crash on Jan. 13.

The bridge's four express lanes, which were closed after the crash to accommodate salvage equipment, were reopened Saturday, and commuters today will have a fighting chance to avoid the massive rush-hour tie-ups that followed the crash of Flight 90.

The airliner hit the bridge's northbound span and plummeted into the Potomac River moments after takeoff from National Airport, killing 74 persons on board and four motorists on the bridge.

The entire bridge was closed after the accident, contributing to what one District of Columbia highway official called "the worst transportation emergency in memory."

Motorists struggled into the city by other routes the morning after the crash. By last week, the northbound and southbound lanes of the bridge had been reopened, but the center span containing the express lanes remained closed.

Although the salvage effort is scheduled to continue today, only small pieces of the aircraft remain under water, and workers no longer need the heavy cranes that had been sitting on the bridge, according to a spokesman for the National Transportation Safety Board, which is investigating the crash.

The one major piece of the wreckage still missing is the main landing gear, which federal investigators would like to examine in their effort to learn why Flight 90 hit the bridge during a heavy snowstorm.

Over the weekend, divers recovered bits of wreckage, and investigators continued studying three vital recordings--two from the airliner itself and a third of conversations between air traffic controllers and the crews of Flight 90 and other airplanes on the runway before the crash.

Investigators today were to release information collected on the airliner's flight data recorder, which was recovered from the icy waters of the Potomac last Wednesday. This recorder collects data that includes the plane's air speed, bearing, altitude and "vertical g-forces" (the rate of upward and downward movement of the plane), according to safety board spokesman Ira Furman.

Furman said the group was prepared to reveal "what we found" on the tape but was not yet ready to interpret the meaning in terms of the possible cause of the crash.

Three of the five survivors remained hospitalized yesterday. Priscilla Tirado, 22, and Joseph Stiley, 42, were reported in satisfactory condition at Arlington's National Hospital for Orthopaedics and Rehabilitation, according to a spokesman. Pat Felch, 27, was in good condition yesterday at the Washington Hospital Center, a spokesman said. Bert Hamilton, of Gaithersburg, another of the crash survivors, was released Saturday from National Orthopaedics.