Political and civic leaders concerned over aircraft noise and congestion in the Washington area generally praised the new flight rules proposed for National Airport yesterday, although some expressed concern that long-standing opposition on Capitol Hill to restrictions at the airport might jeopardize the plan.

"On initial reading, I am pleased," said Rep. Michael Barnes (D-Md.), whose Montgomery County constituents along the Potomac River have repeatedly complained of low-flying jets. The plan's noise standards, limit on passenger loads and flight restrictions would do a lot to satisfy such concerns, he said.

John F. Herrity Jr., chairman of the Fairfax County Board of Supervisors, praised parts of the plan that would improve access to Dulles International Airport and foster development of the surrounding area. "We feel pretty good about winning this one," Herrity said.

The president of the Coalition on Airport Problems, which links civic groups concerned over the frowth of National Airport, called the plan "a first step in the right direction." Eric Bernthal said, however, that his organization had hoped for an outright ban on wide-bodied jets at National, which the plan does not include.

Although Bernthal criticized provisions that would apparently allow certain types of jet airliners to land after 10 p.m., he called the plan "a clear, definitive signal to the airlines that the direction of National is changing." The plan would mean future growth would have to be directed at Dulles, he said.

Rep. Norman Mineta (D-Calif.), chairman of the House aviation subcommittee, labeled the government's attitude toward noise levels "equitable and public-minded" and called for "those with concerns" -- an apparent reference to airlines and congressional opponents -- to work through the public comment and rule-making process "rather than attempting to delay or scuttle the entire policy."

As outlined by Transportation Secretary Drew Lewis yesterday morning, the plan would limit passenger levels at the airport to 16 million a year, hold "slots" for takeoffs and landings to 60 per hour (although shuttle lines would be able to exceed that number if passenger levels required it), and impose noise restrictions between 10 p.m. and 7 a.m. that would preclude most jet traffic.

Stricter noise regulations would come into effect in 1986. According to Lewis, most of the jets now using National would not meet those standards, forcing carriers to use the new, quieter generation of jet aircraft that should be in service by that time.

The plan also proposes accelerating construction of a highway connecting I-66 and the Dulles Access Road to complete it in 27 months. Low-cost or free transportation between Dulles and downtown ticket offices would also be explored under the plan.

Public hearings on the plan are to convene on July 28, with the time for public comment closing on Aug. 21. If approved, the Federal Aviation Administration, the airport's owner and operator, would put the rules into effect on Oct. 25.

Congress does not hold direct powers to rule on the regulations but it could undo them by amending related bills to bar specific aspects of the plan. Last year, airline lobbyists worked energetically against a plan by the Carter administration to reduce traffic at National by 20 percent.

In addition, many members of Congress use the airport, located only minutes by car from Capitol Hill, to commute to their home districts on weekends. Hill aides often trace congressional opposition partly to the inconvenience that such cuts would create for the traveling legislator.

Last year, at least 67 members of Congress signed a resolution opposing any federal move that would "result in a reduction of public air service into Washington National Airport." The Carter administration's plan failed.

Yesterday, members of Congress and aides gave conflicting assessments of opposition the new proposals would face. Rep. Barnes said that "if history is any guide, there will be a response and it will not be muted."

Influential members such as Rep. Gene Snyder (R-Ky.), the ranking minority member on the House aviation subcommittee, has repeatedly expressed opposition to measures to restrict traffic. He has also criticized establishing controls for aircraft noise different from those included in 1979 legislation.

Yesterday Rep. Frank R. Wolf (R-Va.) and other Washington-area members or Congress were considering circulating a letter among their colleagues urging support for the plan. However, Wolf said he was unsure if a concerted effort to block the plan's implementation would emerge this year.

Wolf said factors in favor of the plan include its emphasis on stopping future growth at National rather than restricting current levels, its attention to the problem of safety and development of Dulles and the fact that the Reagan administration and Rep. Mineta of the aviation subcommittee support it.