Six months before Wednesday's crash of an Air Florida jetliner, officials from the Federal Aviation Administration and the District of Columbia staged a mock rescue of 55 passengers of a plane that supposedly ditched in the Potomac River, between National Airport and the Woodrow Wilson Bridge.

While water and aircraft crews were relatively quick to respond to the crisis, staged July 9, an FAA report cited numerous mishaps--including boats running over "victims,"boats overloaded with "bodies" and lapses in radio communications between the rescue workers.

Also, a fire-rescue pontoon boat lost one of its two motors and arrived after the exercise had been completed, according to the FAA report.

The problems cited in the report are significant in light of recurring complaints by Washington-area hospital administrators that the FAA and local police and fire departments have failed to prepare adequate disaster rescue plans.

During another simulated plane disaster near Dulles International Airport Sept. 22, the rescue operation was so mishandled that one busload of "victims" never reached its destination, the Washington Hospital Center.

D.C. City Council member David A. Clarke (D-Ward 1), who has studied airport safety issues, said yesterday that planning for possible aircraft disasters in the area is "grossly inadequate."

"The combined resources of the local jurisdictions is not sufficient to address a tragedy of this nature," said Clarke, who is chairman of a public safety policy committee of the Metropolitan Washington Council of Governments.

Clarke added, however, that he wasn't certain whether any amount of preparation could have saved additional lives Wednesday, when an Air Florida jetliner with 79 persons aboard struck vehicles on and then the guardrail of the northbound span of the 14th Street bridge after takeoff, plunged through the Potomac's icy surface and then quickly sank. Seventy-nine persons have died as a result of the crash, including four who were on the bridge.

Participants in the July 9 rescue exercise, which was staged about 5 1/2 miles south of the Air Florida crash site, included an FAA supervised fire-rescue unit, the D.C. Fire Department, the D.C. police department's harbor branch and an Army helicopter rescue unit, according to a Council of Governments' report.

The exercise was designed to test the response capability of local governments and to identify problem areas, according to the FAA report.

Early on the morning of July 9, D.C. police moved a barge designed to represent the ditched aircraft to the exercise site. Police harbor boats were placed up river as far north and northeast of National as possible while still within the D.C. police department's jurisdiction. Other police units were poised at a pier near the disaster site, and two D.C. fire boats were also available.

Then 55 five-gallon plastic foam containers were dumped into the water near the barge to simulate the plane-crash victims.

The FAA report said that the response from the D.C. harbor police units was "rapid and efficient," as was the response of an airport fire rescue airboat. However, a pontoon boat lost the use of one of its motors and was knocked out of service.

The report noted that during the operation, crew members did not wear flotation gear, rescuers placed too many "bodies" in boats, personnel "threw the bodies off on to shore" and some of the rescue boats "apparently ran over some of the victims."

The report also cited the need for more training in mass water rescue operations, better equipment (some of the units lacked such basic equipment as boat hooks) and improved radio communications equipment.