Carter administration officials are planning to rush a request to Capitol Hill for more than $800 million in new aid to Israel to allow for an immediate start on moving two Israeli airfields from the Sinal Desert, administration sources said yesterday.

The supplemental request will also include an as-yet-undetermined amount of new aid for Egypt, these sources said.

This request for this addition to the current budget could push total government spending for the year over the limit set by Congress, requiring additional corrective congressional action, the sources said.

In meetings yesterday, administration officials began working out details of the complicated new aid programs to Israel and Egypt that will accompany the nations' new peace treaty.

Administration officials emphasized that the $5 billion total price tag cited often in recent days for these aid programs is substantially greater than the amount Congress will actually be asked to appropriate, since a large portion of the aid will be in loans, not grants.

In the past, however, similar loans to Israel have been forgiven.

The only new, outright grant the administration has definitely decided on is $800 million to finance the moving of Israel's Sinai airfields. This project will be supervised by the U.S. Army Corps of Engineers and conducted by the United States outside the Israeli demestic economy, officials said.

The purpose of this arrangement, they said, was to avoid being affected by or aggravating Israel's already-perilous inflation rate.

The United States also plans to extend Israel an additional $2.2 billion over the next three years in foreign military support credits, which Israel theoretically must repay. Congress is asked only to appropriate 10 percent of this money -- the rest of it is considered a loan -- and the administration has not decided what portion of the $2.2 billion should be provided right away.

According to informed sources, the administration is considering these possible options for providing new aid to Egypt:

Selling the Egyptians $1.5 billion in military equipment, some of which is to be financed by U.S. credits. This is less than Egypt has requested, but U.S. officials noted that this would be the beginning of an entirely new military supply relationship between the United States and Egypt.

Additional economic aid beyond the $750 million in security assistance and $200 million in Public Law 480 food aid already proposed in the administration's budget for the next fiscal year.

Guarantees to Egypt that aid of at least this magnitude will be provided beyond next year for some set term.

Egyptian defense minister Kamal Hassan Ali is scheduled to return to Washington at the end of this week to negotiate further details.

Officials said Defense Secretary Harold Brown has given a letter to his Israeli counterpart, Ezer Weitzman, outlining U.S. plans for the $800 million in grants and $2.2 billion in new loans that are now foreseen. Weitzman has been told he can use this letter in parliamentary debate in Jerusalem, the officials said.

A similar letter will probably be given to the Egyptians when final details of an aid program for them are worked out, officials said.

Administration officials expressed concern that Congress might overreact to newspaper reports about $5 billion in new aid commitments, and emphasized repeatedly that the administration would be seeking a much smaller amount in actual appropriations.

They also noted that whatever the size of the new commitments, they will be considered in the context of the foreign assistance legislation, described by one official as "the most disliked bill on Capitol Hill."

Yesterday was relatively calm on the Mideast front in Washington because the Israeli and Egyptian officials who had been here for intensive negotiations earlier have gone home.

Israel's foreign minister, Moshe Dayan, is scheduled to arrive tomorrow to complete negotiations on the one remaining substantive issue, the precise timing of Israel's staged with-drawal from the Sinai.