Deletions from yesterday's quotations from a transcript of the cockpit tapes on the crashed Air Florida jet were made by the National Transportation Safety Board to remove nonpertinent words.

The pilots of the Air Florida jet that crashed into the Potomac River three weeks ago joked repeatedly and somewhat nervously about poor weather and ice on their plane's wing while waiting to take off, a transcript of the cockpit tape shows. But each time, they stopped short of returning to the terminal for another de-icing treatment.

"Boy, this is shitty, it's probably the shittiest snow I've seen," copilot Roger Alan Pettit remarked 20 minutes before the plane took off in a blinding snowstorm the afternoon of Jan. 13. About 30 seconds after take-off, the Boeing 737 struck the 14th Street bridge and plunged into the river, killing 74 people aboard the plane and four people on the bridge.

"Boy, I'll bet all the school kids are just deleted in their pants here. It's fun for them, no school tomorrow, ya hoo," Pettit remarked while the plane waited in line to take off.

Twelve minutes before takeoff, Pilot Larry Wheaton, apparently referring to ice or snow on the jet's right wing, said: "I got a little on mine." Pettit responded: "This one's got about a quarter to half an inch on it all the way." Transcript of voice tape starts on Page A12.

Ice can be a problem because it affects a wing's ability to lift a plane. Its role in the Air Florida crash is being closely scrutinized by federal investigators.

During their taxi, the pilots apparently pulled the plane close to a New York Air plane in front to try to use its jet exhaust to melt the ice that formed on the wing of their plane. "Don't do that Apple, New York Air's code name ," pilot Wheaton said eight minutes before takeoff, suggesting the other jet had moved away or throttled down. "I need to get the other wing done." The sound of laughter followed.

Shortly before being cleared for takeoff, Pettit noted that the plane would have to accelerate on a "slushy runway." As the plane proceeded down the runway, the pilots sensed almost immediately that something was wrong. Once in the air, the transcript indicates that they fought to get the jet's nose down and stabilize it.

One second before crashing, copilot Pettit said: "Larry, we're going down, Larry." Pilot Wheaton responded. "I know it." Impact came at one second after 4:01 p.m.

The National Transportation Safety Board, which released the transcript of the tape yesterday, refused comment on its contents, as did other agencies involved in the investigation.

However, the pilots' words are certain to become an important factor in the investigation because they suggest strongly that the crew violated Federal Aviation Administration regulations against taking off with ice on the wings.

Investigators have also noted that the pilots could have had strong psychological incentives to take off. They were behind schedule; the runways had been plowed; and many planes had taken off ahead of them with no problem.

Safety board officials stressed that they still are deciphering the tape, which divers recovered from the bottom of the Potomac. In the transcript released by the board yesterday, words that remain unclear were placed in parentheses.

The transcript opens at 3:30 p.m., about 15 minutes after the plane was sprayed with a de-icing solution for the last time. The crew's recorded conversation began with an apparant discussion of a tractor's inability to pull their 737 away from the gate. Five minutes later, after noting the arrival of another tractor with chains, Pettit remarked on the plane's weight, then said: "Maybe we can taxi up side a' some seven two Boeing 727, a common plane at National sittin' there runnin', blow off whatever (accumulated on the wings)."

He was apparently suggesting that they taxi close behind another plane and use its exhaust to melt any snow or ice on their wings. Aviation sources say they believe such a maneuver could be dangerous, because vaporized snow might refreeze on contact with the cold wings as solid ice.

At 3:40, Pettit remarked that "It's been a while since we've been de-iced." Wheaton responded by saying, "Thank sic I'll go home and (play)." The rest of his answer was unintelligible.

At 3:46, Wheaton said: "Tell you what, my windshield will be de-iced, don't know about my wing." Pettit answered: "Well, all we really need is the inside of the wings anyway, the wing tips are gonna speed up by 80 knots anyway, they'll, they'll shuck all that other stuff." Laughter was heard.

At 3:47, Wheaton said: "(Gonna) get your wing now." Pettit said: "D'they get yours? Can you see your wing tip over 'er?"

Wheaton: "I got a little on mine."

Pettit: "A little . . . This one's got about a quarter to a half an inch on it all the way."

This exchange could mean the Air Florida jet pulled up behind the New York Air DC-9 and attempted to de-ice its wings. The pilots then peered out their windows to check the results and found that some ice remained. However, some sources close to the investigation have cautioned that it is possible the crew were referring to ice on another plane.

At 3:53, Pettit said: "Boy, this is a, this is a losing battle here on trying to de-ice those things, it (gives) you a false feeling of security that's all it does." Wheaton answered: "That, ah, satisfies the feds."

Pettit, who was at the controls during the takeoff, asked at 3:58: "Slushy runway, do you want me to do anything special for this or just go for it?" He then suggested lifting the nosewheel early, to reduce the drag that would be caused by the slush. Some aviation sources say this is generally a maneuver appropriate only for small planes.

Following takeoff clearance and a preflight checklist that aviation sources have described as complete and in good order, the engines are heard gaining thrust at 12 seconds before 4 p.m.

Within seconds, Wheaton remarked, "Real cold . . . real cold" -- an expression of concern that has puzzled investigators. "That don't seem right, does it? . . . Ah, that's not right," Pettit said a few seconds later, in another reference that has not been clarified.

Wheaton calledout the acceleration of the plane -- it was taking an unusually long time to reach takeoff speed. Two seconds after reaching a speed normally safe for climbing out of an airport, the pilots' control sticks could be heard shaking, a warning that the plane was about to stall, or fall due to loss of lift.

At 45 seconds after 4 p.m. Wheaton said: "Forward, forward," then "we only want 500." There was speculation yesterday that he was trying to push back on the control stick and bring the nose down, but pilots disagreed on whether "500" referred to 500 feet altitude or 500 feet per minute rate of climb.

Boeing has cautioned operators of the 737 that the plane can pitch up at the nose without warning during icy takeoffs. Investigators have speculated that the pilots were wrestling with that control problem. "Come on, forward . . . forward . . . Just barely climb," Wheaton continued.

"(Stalling) we're (falling)," Wheaton said. Then Pettit spoke: "Larry, we're going down, Larry." Captain Larry Wheaton: "I know it." Impact occurred almost simultaneously with those last words.