The Federal Aviation Administration yesterday demoted the Delta Air Lines pilot who erroneously shut down a jetliner's engines while taking off over the Pacific Ocean by stripping him of his captain's license.

John Henry Gilfoil of Los Altos, Calif., will retain his commercial license, meaning he can fly as a copilot or a flight engineer, said Fred Farrar, an FAA spokesman. But he can no longer fly as a captain.

Gilfoil, a 29-year veteran of Delta, was captain of Flight 810 to Cincinnati June 30 when he shut off both engines of a two-engine Boeing 767 jetliner after taking off from Los Angeles International Airport. The plane dropped to 500 feet above the ocean and the 205 passengers on board were told to get ready to crash before Gilfoil was able to restart the engines and fly on to Cincinnati.

Meanwhile, Delta has suspended the cockpit crew of a Lockheed L1011 that nearly collided with a Continental Airlines jumbo jet over the North Atlantic July 8, aviation sources said. The captain was suspended without pay for a year, the copilot for three months and the flight engineer for two months.

Delta has been plagued by pilot errors over the last month. The incidents prompted an FAA investigation of Delta's pilot training program.

Delta's troubles began June 18 when a Delta jetliner attempted to take off from Nashville at the same time a Southwest Airlines jet was taking off from the opposite end of the runway.

On July 7, a Delta pilot flew out of a thunderstorm and landed in Frankfort, Ky., instead of his destination in Lexington 19 miles away.

The next day, the L1011 strayed 60 miles off course over the North Atlantic and nearly collided with the Continental jet. The two planes, carrying almost 600 people, passed within 100 feet of each other, according to sources close to the investigation.

On July 12, a Delta pilot landed on the wrong runway at Boston's Logan International Airport.

In the Los Angeles incident, FAA investigators concluded that Gilfoil shut down the right engine after he saw a light indicating that the jetliner's right fuel control switch, known as the electronic engine control, was malfunctioning. Gilfoil then shut down the left engine along with the left engine control switch.

The electronic engine control switch is a computerized device that controls the fuel flow to the planes' engines to ensure the most optimum fuel efficiency. Fuel flow can be controlled manually, Farrar said, and it was not necessary to shut down either of the plane's engines if either fuel control switch was malfunctioning.

Investigators said Gilfoil did not notify the plane's copilot before he shut off the engines, a violation of Delta's cockpit procedures. A 767 is flown by a two-member crew.

The plane, which had climbed to about 2,000 feet, fell to 500 feet while the engines were off.

"As a result of the above," the FAA order to Gilfoil said, "you have demonstrated you do not possess qualifications necessary to hold airline transport pilot privileges."

Shortly after the incident, the FAA issued an emergency directive to the Boeing Co. asking the manufacturer to place a plastic barrier between the fuel control switches and the engine switches so the engines could not be inadvertently turned off.

Farrar said Gilfoil may appeal the action to the National Transportation Safety Board, but the certificate revocation remains in effect during the appeal.

Bill Berry, a Delta spokesman, said Gilfoil was suspended immediately after the incident and is no longer receiving his salary. Berry declined to say whether Gilfoil will be reinstated. He said the copilot on Flight 810 was returned to flying duty.

Gilfoil could not be reached for comment.

Berry said Delta was not surprised with the FAA's move, but added the airline has completed an internal investigation.

The FAA is most interested in the North Atlantic incident, which was observed by crews flying American Airlines and Pan American World Airlines jetliners. During a conversation involving the four cockpit crews, a suggestion was made that the incident be covered up. The conversation was recorded by a nearby Air Force jet and a transcript of it is being reviewed by the FAA.