Some of National Airport's most avid customers -- members of Congress -- stepped up one by one at a House subcommittee hearing yesterday to blast Federal Aviation Administration plans to reduce noise and congestion at the popular, close-in facility.

Washington area residents who complain about noise from jets flying into and out of National are "nothing more than a bunch of spoiled brats . . . who are being pandered to by the FAA," Rep. Sam M. Gibbons (D-Fla.) told the House Aviation Subcommittee.

Gibbons said his residence in Southwest Washington "is closer to the airport than most of those who are bellyaching and crying" about excessive noise generated by the more than 600 daily commerical flights at National.

The Tampa Democrat was the most outspoken critic who testified yesterday, but he was not alone in protesting the FAA proposal, which would reduce the number of flights by 20 percent and impose a strict 9:30 p.m. curfew on takeoffs and landings at the new-downtown airport.

Because of its proximity to the Capitol -- Rep. Bill Nelson of Florida said its takes him only 10 minutes to drive from his office -- and because it offers free parking next to the terminal for commuting congressmen, National is sometimes called "the congressional airport." Rep. Samuel L. Devine of Ohio said he will make his 1,530th trip between National and Columbus this weekend.

Many members of Congress commute each week between their home districts and the Capitol, leaving Washington each Thursday or Friday, and returning on Sunday or Monday. Both National and Dulles provide special parking areas for commuting dignitaries, but National is by far the more popular because of its location.

Nevertheless, most of yesterday's congressional witnesses testified that they oppose any reduction in the number of flights at National -- a few even want more -- not for themselves, but for their constituents.

Devine, who has been commuting for 22 years, said he recalls "the moans and wails" of area residents when the airport made the transition from piston to jet aircraft years ago. "But none of their dire predictions came true," Devine told Committee Chairman Glenn M. Anderson (D-Calif.).

The FAA plan to reduce the number of flights at National is an attempt to "force air passengers to bail out (the FAA) for the bad decision" to build Dulles Airport so far from the city, Devine said.

Gibbons also dismissed the testimony of his congressional colleagues from Maryland who testified Wednesday in favor of the FAA proposal, as an "attempt to force people to go to the airport (Baltimore Washington International) that they built in the wrong place."

National is five miles from Capitol Hill, just across the Potomac River in Virginia, while both Dulles and BWI are more than 25 miles away. As a result, smaller, overcrowded National is the nation's 12th busiest commercial airport, (16th in the world), handling more than two-thirds of all airline passengers who use the three airports. In 1979, National attracted 15,197,133 passengers; BWI 3,869,692 and Dulles 3,064,728.

While Gibbons urged the subcommitte said he saw nothing wrong with "using some of our clout" for the congressmen's own purposes.

Rep. John G. Fary (D-Ill.) said he wants "the privilege of bypassing all those other people who are standing in line to be frisked" by security police when he makes his weekly around trip to Chicago. "If you want to call it clout, OK let's use it," Fary uurged.

While the House members from faraway districts who testified yesterday were unanimous in opposing at least part of the FAA plan, they were not united on what changes, if any, should occur at National.

For example, North Carolina Democrats Stephen L. Neal and Charles Whitley argued against the part of the plan which would extend from 650 miles to 1,000 miles the distance for nonstop flights from National.

"New service to more distant cities inevitably means less service to nearby cities in states like North Carolina, Virginia and West Virginia," said Neal, who is from Winston-Salem.

But Rep. Lindy Boggs (D-La.) favored the 1,000-mile limit, saying it would allow her constituents in New Orleans to fly directly to Washington. Now, she said, "we must go through Atlanta wherever we go, and some believe that includes trips to heaven and hell," Boggs said.

Rep. John H. Buchanan Jr. (R-Ala.) also said he favors the 1,000 limit, adding that Birmingham passengers must transfer in Atlanta because their hometown airport is 653 miles from National.

Adoption of the 1,000-mile perimeter would end discrimination against Birmingham, New Orleans, Fort Lauderdale and Kansas City, which failed to win "grandfathered" exclusions, as did seven equally distant cities, when the 650-mile limit was established 15 years ago, Buchanan said.

To compensate for the added distance, the FAA has proposed allowing two- and three-engine widebody jets to use National, but questions about their safe use at the congested airport were raised Wednesday by officials of the Air Line Pilots Association.

Rep. Bob Carr (D-Mich.) who commutes from Lansing in his own plane, warned that National is "overdue for a major accident."

All of yesterday's witnesses said safety should be a primary concern in what ever changes are made, but most members said they thought the FAA's proposals were offered in reaction to noise complaints, rather than safety problems.

"As many as can be handled safely," was the limit proposed by Rep. Claude Pepper (D-Fla.), who urged, "don't worry about noise. People learn to live with noise."

Pepper said he used to have a house in Coral Gables under the flight path of Miami airport, but "when we were sitting around the pool, and a plane went over, I never noticed anyone turning in his glass and going home."