Maj. P. Drax Williams tugged back on a lever, reining hsi AV-8A Harrier jet from a screaming 500 miles per hour to a midair halt and let it hover over a Marine Corps runway near here like some angry hummingbird.

"It's like Buck Rogers," Williams had promised earlier in the day, describing the jet fighter that performsrm like a helicopter. And, as he let the Harrier feather down onto the runway for a landing, his description of the aircraft was undeniable is the hefty accident rate U.S. Marine Corps pilots have charted in the British-built "VSTOL" aircraft (VSTOl is an acronym for vertical and short take off and landing.) The Marines have purchased 110 Harriers at $3.4 million apiece since 1971, and 22 of them - one out of five - have crashed.

The seven lives, $63.6 million and 16 airplanes those 22 crashes have wasted is distressing to the Marines. "We're concerned about the accident rate, no doubt," said Brig. Gen. Leo J. LeBlanc, Jr., Marine Corps assistant deputy chief of staff for aviation.

Even more disconcerting is the steep climb of the Harrier accident rate in the past three years - the very period in which, experts said, familiarity with the airplane and the greater experience of pilots should reduce the mishaps.

Four Harriers fell from the skies near the Marine Corps Air Station here, where three of four U.S. Harrier squadrons are based, between Feb. 11 and April 18 of this year. Those crashes brought to 16 the number that have gone down since 1975.

"The normal tendency of that curve is to be rather high to begin with and to come down," acknowledged LeBlanc. "That has not been the case with our aircraft." As for the four most recent crashes: "I think we've hit one of those periods."

Wing Cdr. John M. Curry of the air attache's office in the British Embassy would not release accident statistics for the 109 Harriers bought by the Royal Air Force since 1969. "I'm afraid that's regarded at home as classified," he said.

Also classified, LeBlanc said in a telephone interview from Washington, are the official reports on why 22 Marine Corps Harriers have crashed.

But a clue may exist in unusual and difficult maneuvers the Harrier performs - the same manuuvers that sold the Marines on the airplane and gave Hawker Siddelev Aviation Ltd. of England the distinction of being the first foreign firm to sell the United States a major weapons system.

The Harrier is the first operational aircraft in the western world that uses VSTOL concepts that are rewriting air warfare tactics.

Yet, until the past few years, the United States had been slow in getting to work on VSTOL. That has changed dramatically.

"Why all the action in the VSTOL area?" wrote Aerospace Daily reporter John Rhea in the November, 1976, issue of Sea Power magazine. "One explanation offered is the recent appearance of the Soviet YAK-36 VSTOL on the deck of the carrier Kiev - a technological surprise which has been described as the "Spuknik of the VSTOL business.'"

"The (VSTOL) are the plane I am convinced will be the backbone of our aviation force at sea when we cross into the 21st century," asserted navy Secretary W. Graham Clayton in a speech less than a month ago.

An advanced VSTOL aircraft ia a key part of the Navy's master plan for the fleet of the 1990s.

If a safe VSTOL plane that can carry a bigger load than the Harrier cannot be developed in time to join the fleet in the 1990s, the whole concept of witching from Nimitz-class carriers, which cost $2 billion each, to "midi-carriers" costing half that will have to be reconsidered.

The Harrier can take off going straight up, hover, move backward or sideways as well as forward, brake from top speecd to a midair stop in 1,000 yards, and can land in forest clearings or on ship decks as small as 72-by-72 feet in area.

And, of the 22 major Harrier accidents reported by the Marines, 11 have occurred when the airplane was performing those vertical takeoffs and veritcal landings or was in transition from normal flight to the hover.

Engineering marvels enabl it to make those maneuvers. Four jet exhaust nozzles direct the thrust of the harrier's Pefasus engine. They can be pointed directly aft for conventional flight, straight down for hovering or vertical takeoffs and landings, and at angles in between for takeoffs from as little as 500 feet of runway.

During veritcal flight, four "puffer ducts" - small nozzles on the nose, tail and wingtips that produce thrust control the plane.

The puffer ducts are designed to work automatically when the exhaust nozzels are turned vertical, but Herrier pilots say making the transition form normal flight to the hover and using the puffer ducts corretly are demanding tasks.

"You're going from high speeds to low speeds," Lelanc said, "and the airplane doesn't act like a normal airplane."

Maj. M.H. Brannum, a former test pilot and head of offensive air support systems for the Marines, went into more detail.

"Your conventional flight controls - your wing, vertical tail and horizontal aircraft" at speeds greater than 120 knots, Brannum said. But at speeds lower than that - such as when the Harrier is being slowed to a hover - he said, the airplane "just kind of wants to wander aroaund on its own."

Observed A.E. Stark, Hawker Siddley's military liaison in Washington, "With inexperienced pilots, the airplane has a tendency to get a head of them, which is where most accidents occur."

Until a couple of years ago, the Marine Corps reserved the Harrier ofr only the most experienced of pilots. And LeBlanc conceded that, considering the difficulty of flying the airplane, "we might have been just a little too quick on relaxing the standards. We're looking at our selection procedures and tightening them up."

Another problem the marines encountered with Harrier, according to a General Accounting Office report released in January, was the difficulty in maintenance. because of the distance between factory and customer, the GAO said, the Marines could repair only about 30 per cent - instead of a usual 90 per cent - of the aircraft's comp/nents.

The result, the GAO reported, was the average monthly rate of Harriers not operational was 67 per cent - "well above the acceptable 40 per cent level."

But, said GAO audit manager Terry A. Kramer, the Marines claimed that maintenance problems did not contribute to the crashes.

Despite its promise, the Air Force and Navy rejected the VSTOL because of its short range - 360 miles - and its inability to carry its normal payload of 8,000 pounds of armaments when taking off or landing vertically.

Neither does the Harrier stack up, concluded military analyst Michael Krepon in the January issue of Foreign Affairs, a quarterly, agianst the Soviet YAK-36. In fact, Krepon argued that "the United States has a long way to go to attain the performance needed out of these experimental aircraft."

Still, said LeBlanc, "We're satisfied with what we have."

The Marine Corps, being primarily an invasion force, has fallen in love with the Harrier because the tight spots in which it can land and takeoff would allow it to operate in combat from only a few miles behind the front or just off shore in a conventional war.

Ground troops in the VIetnam war depended for air support in planes based miles away from the action, recalled pilot Williams, and when the call came for strafing or bombing, "we ran an average of 20 to 25 minutes for a sortie."

With the Harrier, he said, "By the time the forward observets pick out target, we can have two birds overhead."