What was going on when I was born?

Juan Trippe, a pioneer in international aviation and jet passenger travel for American airlines, died yesterday in his apartment on Fifth Avenue. He was 81 years old. Mr. Trippe was a founder of Pan American World Airways, and under his direction, the airline became the first to fly across the Pacific and the Atlantic Oceans, the first to put American-made jets into commerical use and the first to order the Boeing 747. Mr. Trippe and some friends from Yale started a charter service and sightseeing company on Long Island in 1923 with a handful of surplus World War I Navy planes. He went on, four years later, to lead in the creation of Pan Am.

Israel has asked the United States for an outright gift of an additional 15 F-15 fighters as well as access to an American spy satellite to compensate for the Reagan Administration's planned sale of advanced military equipment to Saudi Arabia, Administration and Israeli sources said today. With Secretary of State Alexander M. Haig Jr. leaving tonight on a nine-day trip to the Middle East and Europe, the American military relationship with Saudi Arabia and Israel has become complicated by a possible arms race that seems to have been inadvertently set off by an American desire to build up Saudi defenses against any Soviet threat. Mr. Haig conferred with President Reagan at George Washington University Hospital this morning and received last-minute messages for the leaders he will meet on the trip. Mr. Haig will spend one day each in Egypt, Israel, Jordan and Saudi Arabia. On Wednesday he will fly to Spain with a stop in Italy. On Thursday he will go to Britain, then stop in France and West Germany before flying back to Washington a week from tomorrow.

Five years ago, when construction of the Ohio, the first of the Navy's planned fleet of Trident ballistic missile submarines, began here at the Electric Boat Division of the General Dynamics Corporation, the new vessel was the pride of the Navy's future. Larger and more powerful than any American nuclear submarine built before, the Ohio and her 26 sister Tridents were to be the heart of the United States sea-based strategic forces in the 1980's and 1990's. Now, with the Ohio more than two years behind schedule and $280 million beyond original cost estimates, Navy Secretary John F. Lehman Jr. has notified the chairman of General Dynamics, David S. Lewis, that ''it may be necessary to consider alternatives to the Trident class submarine.'' Charges Heard by House Panel Top officials of the Navy and Electric Boat have traded charges about delays and costs of the Trident program in separate appearances before the House Armed Services Subcommittee on Seapower. Interviews with more than 20 current and former Defense Department officials, Electric Boat employees and military procurement experts in Washington, and a review of public records on the Trident program suggest that explanations are not that simple nor villains so clearcut.

The United States said today that Soviet forces around Poland had made new preparations that would enable them to go into action at a moment's notice and again warned Moscow that such ''unjustified action would have the gravest consequences for East-West relations.'' According to informed sources, the Soviet Union began airlifting helicopters into Legnica, the Soviet military district headquarters in southwest Poland, in an action that appeared to be on a small scale to avoid attracting attention and generating alarm in Poland. Defense Secretary Caspar W. Weinberger, questioned before he left on a trip to Western Europe, declined to comment tonight on the Legnica report. But other high-ranking officials said there was no evidence that an intervention was under way or that the Soviet Union had made a decision to intervene with force in the Polish crisis.

Eight of Canada's 10 provincial premiers will meet in Ottawa April 16 in their strongest bid yet to defeat Prime Minister Pierre Elliott Trudeau's constitutional proposals, but Mr. Trudeau, speaking yesterday in New York, said he was ''not impressed.'' The Canadian leader appeared in a fighting mood on the constitutional issue as he spoke on wide range of domestic and international problems in a session with editors and reporters of The New York Times. Of all his concerns, Mr. Trudeau made it clear that the one closest to his heart was Canada's future as ''a strong, united nation'' rather than as ''as a confederation of shopping centers.'' Mr. Trudeau came to New York principally to attend a Metropolitan Opera gala tonight. Behind him in Ottawa he left a House of Commons that has been paralyzed for a week on the constitutional issue. The paralysis stems from a decision by the Progressive-Conservative opposition to prevent, by procedural maneuvering, the final consideration of a resolution asking Britain to end its control over the British North America Act, which serves as the country's Constitution.

President Reagan had a fever of 102 degrees this morning, but by afternoon it had dropped to near the normal 98.6 degrees in what his doctors called ''a bit of a setback'' in an otherwise uneventful, rather ''remarkable'' recovery from a bullet wound in his left lung. Tonight, the White House said Mr. Reagan's temperature had gone up again, to 101 degrees, late in the day after doctors used a tube to remove blood particles he had been coughing from his wounded lung. Dr. Daniel Ruge, Mr. Reagan's personal physician, said in an evening medical bulletin that Mr. Reagan's condition ''is satisfactory'' and he ''remains alert and generally comfortable.'' ''We are curtailing his schedule,'' Dr. Benjamin L. Aaron, one of Mr. Reagan's surgeons, said at a news conference earlier at George Washington University Hospital, where the President is a patient. The surgeon also said that breathing exercises were being increased to help a section of Mr. Reagan's lung return to normal function.

Under pressure from Assembly Speaker Stanley Fink, Governor Carey today called a special session of the State Legislature for noon tomorrow to attempt to pass a budget for the fiscal year that began Wednesday. But the Governor said the agenda, which is under his control, would consist of the $16.5 billion budget that the Democratic-controlled Assembly had passed at his behest. As a result, the Republican leaders of the Senate questioned whether the special session would be productive. The Senate's chief fiscal officer, James L. Biggane, who is secretary to the Senate Finance Committee, said that if the Governor was not willing to negotiate, the Senate would simply amend the special-session budget bills to make them, in essence, the Senate's own plan, which was adopted Tuesday.

Large increases in the prices of oil products were the key factors in pushing up the Producer Price Index last month by 1.3 percent, to an annual rate of 16.8 percent, the Bureau of Labor Statistics reported today. However, outside of the energy area, the Government's measure of what producers were charging for goods ready for shipment to retailers continued to show only a moderate increase, despite the first rise in producers' food prices since November. Janet L. Norwood, the commissioner of the labor statistics bureau, told the Joint Economic Committee of Congress that the jump in energy prices ''reflected the impact of price deregulation of domestic crude oil as well as increases in the prices of imported petroleum.'' The Organization of Petroleum Exporting Countries also decided in December to raise its crude oil prices.

Arab-Americans yesterday denounced Richard V. Allen, President Reagan's national security adviser, for saying that Israeli raids into southern Lebanon could be ''justified'' as ''hot pursuit.'' They called for his resignation and for a repudiation of his statement.

A cease-fire was reported tonight in the eastern Lebanese Christian town of Zahle after two days of artillery duels between Syrian troops and Christian militiamen. The state-controlled Lebanese television indicated that the guns were silent because of intervention by President Hafez al-Assad of Syria. President Elias Sarkis of Lebanon had telephoned Mr. Assad and also sent an envoy, Elias Herawi, to Damascus to ask his help in ending one of the worst outbreaks of violence since the 1975-76 civil war.

With a two-day coup attempt crushed, Prime Minister Prem Tinsulanonda pledged today to give ''a fair judgment'' to the rebels. He called on them and all the Thai people to ''forget what happened'' and to get on with serving the nation. The statement was issued from the military base 130 miles to the northeast where the Prime Minister had taken refuge with the royal family when the uprising began early Wednesday. There were no casualties until this morning, when the rebellion collapsed as thousands of troops loyal to the Prime Minister swept into the capital, encountering little resistance.

President Reagan has selected the actor John Gavin to be Ambassador to Mexico, the White House announced today. The nomination of the 49-year-old Mr. Gavin, whose films included ''Psycho'' and ''Imitation of Life,'' had been expected.