The Federal Aviation Administration and the Office of Management and Budget are locked in a debate over money that has slowed FAA plans for a new radar system that can detect the wind phenomenon suspected of causing last Friday's Delta Air Lines crash in which 133 people died.

FAA Administrator Donald D. Engen said in an interview yesterday that research and development is proceeding for airport-based Doppler radar systems, but conceded that he has to battle with OMB before he can go forward with procurement.

"It's a justification process; it's our government at work," Engen said. An airport Doppler system to warn flights of treacherous "microbursts" on takeoffs and landings "is needed" and he is committed to fighting for it, Engen said.

A microburst is one type of wind shear, where suddenly shifting wind directions can destroy an airplane's ability to fly, especially if the condition is encountered at low altitude where a pilot has little room to adjust to surprise conditions.

A microburst wind shear in the midst of a thunderstorm is the leading suspect in the Delta Flight 191 crash at Dallas-Fort Worth International Airport. The National Transportation Safety Board investigation of that crash continued yesterday.

The radar Engen wants could cost between $3 million and $4 million installed, per airport. Five hundred U.S. airports handle scheduled airline flights. The FAA's intention would be to phase in the system, first at the five or six major airports located in thunderstorm-prone cities, including Dallas-Fort Worth.

OMB has asked the FAA to determine if an existing "shelf-item" radar system could do the job for less money, and the FAA is studying that question with an answer expected this fall. Engen said he hopes to expedite the study, but also said that "we feel it is better to go with upgraded technology" such as that under development.

A potential additional problem for Engen is the Air Line Pilots Association's push for a different kind of microburst detection system, one that would be in the cockpit.

Neal A. Blake, the FAA's deputy associate administrator for engineering, said, "We have brought the airport Doppler radar to the point where we can go to production. We're a long way from development of an airborne system."

The conflicts over money and whether a safety system should be ground-based or cockpit-based point up the continuing political warfare that surrounds aviation safety. A similar debate has raged for years over collision avoidance: Whether the air traffic control system should have primary responsibility or whether the responsibility should rest in the cockpit.

The advantages of Doppler radar in detecting severe weather have been known to researchers for years. Last summer, after a United Airlines flight narrowly escaped disaster in a microburst at Denver's Stapleton International Airport, the FAA commissioned a study to see if a Doppler radar could warn pilots of microbursts before they happened.

In a 45-day period, 35 of the microburst advisories issued as a result of Doppler radar surveillance gave a two- to four-minute advance notice of microburst activity.

"We have a written statement from one pilot that it saved his airplane," said John McCarthy, who headed the project for the nonprofit National Center for Atmospheric Research and who has done extensive missionary work with pilots on the dangers of wind shear.

Additionally, the Doppler radar gave the air traffic control tower 15 to 20 minutes of additional warning of coming shifts in primary wind direction, thus permitting runway changes without as many holding patterns and flight delays as inevitably occur during a runway change at a busy airport today.

The airport radar systems would be an outgrowth of the so-called NEXRAD development. NEXRAD, a joint effort by the Commerce, Defense and Transportation departments, stands for Next Generation Radar. Richard E. Hallgren, director of the Commerce Department's National Weather Service, said yesterday that NEXRAD prototypes developed by Sperry and Raytheon in competition will be completed late in 1986. However, he said, "We have not been funded for limited production."

Rep. Norman Y. Mineta (D-Calif.), chairman of the House Public Works Aviation subcommittee, announced that he will hold hearings and said that efforts to develop warning technology "need to be accelerated. This tragedy should put to rest the efforts by the White House and the Office of Management and Budget to slow down the funding for implementation of the NEXRAD technology."

The Doppler radar, named after the "Doppler effect," can "see" things the human eye cannot. The "Doppler effect is that a sound such as an automobile horn moving toward a listener will have a different pitch and tone than it will have as it moves away.

That same principle, applied to radar, is that if there is a wind shear, it will be displayed on the screen because winds would move sharply in one direction, then be calm, then move sharply in another.

To be most effective in detecting wind shears, the radar needs to be aimed very close to the ground, where buildings, towers and other obstacles clutter the image. The FAA is working at Memphis to learn ways to defeat "ground clutter." Other questions are where best to locate the antennas and whether more than one antenna would be needed for a major airport.

Delta Flight 191 apparently encountered a wind system that was particularly difficult to see with the human eye, either from the cockpit or from the control tower, according to several sources.

Rudolf Kapustin, the safety board's investigator in charge, said that on the cockpit voice recording on the last minutes of the flight, "We hear nothing but what I would characterize as professional discussion of operational matters. The crew was very professional, attendant and knowledgeable of what was going on."

Safety Board Member G.H. Patrick Bursley said that a Flight 191 crewmember radioed the control tower that the plane, a Lockheed L1011 jumbo, was "entering a rain shower . . . . Feels good." Bursley said that transmission is "suggestive that no one expected anything violent."

Capt. Patrick W. Clyne, coordinator of aviation weather projects for the Air Line Pilots Association and who is a Northwest Airlines pilot, said that "In most of these encounters, crews are utterly unaware of the danger that surrounds them. Usually the onset of the event is insidious and is well developed by the time the crew recognizes they are in desperate trouble . . . . "