Directors of the new regional airport authority, preparing to assume control Sunday of National and Dulles International airports, appointed the first members yesterday of the congressional board that will monitor the authority's major actions.

The nine-member review board will have powerful veto power over the Metropolitan Washington Airports Authority, but is expected to exercise that power only rarely because it is appointed by the body it will review.

The first five appointees, selected from seven names suggested by the Speaker of the House of Representatives, all were supporters of the law transferring the airports from federal to regional control. The review board, proposed by Rep. Norman Y. Mineta (D-Calif.), was included in the legislation as a last-minute compromise to win crucial votes from members of Congress who were reluctant to give up control over National.

By letting go of day-to-day operations of the federally owned airports, the government will rid itself of the problem of paying for an estimated $700 million in improvements needed at aging National and overburdened Dulles.

While Congress struggles for ways to cut federal spending, the new authority will have the power to issue bonds to finance new terminals, runways, road, parking areas and other facilities.

With five members, the review board will have a quorum enabling it to act. It has veto power over five actions by the authority board: adopting an annual budget, appointing a chief executive, promulgating regulations, developing a master plan for construction at the airports and authorizing bond issues.

Although future review board members will serve six-year terms, assuming the representatives hold their House seats, the first appointments are for staggered terms.

Without debate, the authority board unanimously appointed Mineta and John P. Hammerschmidt (R-Ark.) to six-year terms; William Lehman (D-Fla.) to a four-year term; and Silvo O. Conte (R-Mass.) and Dan Rostenkowski (D-Ill.) to two-year terms.

Four senators will be appointed after the authority receives nominations from Sen. John C. Stennis, the Senate's president pro tempore. Rostenkowski was appointed to a seat that will be filled alternately from each chamber, and thus will be taken by a senator in two years.

Although some local officials and lawyers have raised questions about the constitutionality of the review board, no known legal challenge has been launched.