Transportation Secretary Drew Lewis proposed yesterday delay from April until October the grand plan he inherited to cut jetliner flights at Washington National Airport by about 20 percent and thus reduce jet noise.

The term "proposed" is a legal technicality. In fact, sources report, Lewis has already decided the contoversial issue must be studied by the Reagan administration and the delay will be needed to provide time. "We think we can come up with something that's better than everybody's come up with," a Lewis aide said.

If Lewis does not act or if Congress does not intervene, the plan of former secretary Neil Goldschmidt will take effect April 26.

Reaction to Lewis' proposed delay was swift.Eric Bernthal, president of the umbrella antinoise citizens group called Coalition on Airport Problems, called it outrageous. "This policy represents the culmination of literally years of examining the question and this was a carefully crafted compromise among the competing interests at National who have been fighting among each other for 15 years," Bernthal said.

A spokesman for Rep. Gene Snyder (R-Ky.), one of the many influential members of Congress who want access to convenient National eased, not restricted, said, "It's only fair to let the secretary work up another scheme."

National Airport is only 10 minutes by car from Capitol Hill. Many members of Congress, including Snyder, fly their planes there. The alternative airports, Dulles and Baltimore-Washington International are at least 60 minutes away during rush hour.

Sen. John Warner (R-Va.) and Rep. Frank Wolf (R-Va.) characterized the delay as "regrettable" and "disappointing," and urged Lewis to complete his review in less than the announced six months.

The plan Lewis will be reviewing calls for a reduction in the hourly jetliner flights from 40 to 36, an absolute instead of voluntary nighttime curfew for all flights, the admission for the first time of jumbo jets, a 17 million annual ceiling on the number of passengers using the airport, and extension from 650 miles to 1,000 miles of the permitted distance for nonstop flights.

"It's important to consider whether there may be more effective and appropriate ways to control commercial flights and aircraft noise," Lewis said, in announcing his proposed delay.

In addition to providing noise relief, the plan would force future airline growth to Dulles or BWI and permit badly needed renovation of the road network and terminal facilities at National. National had 14.5 million passengers last year, a slight drop in a bad year for airlines generally, while Dulles had only 2.5 million, a precipitous 25 percent decline.

The department will accept comments on the proposal to delay until March 19.

The planned delay and possible change of policy come at a time when the airline business is increasingly competitive because of deregulation and the question of who gets access to highly desirable airports is harder and harder to answer. o

The Airline Scheduling Committee, which met quietly for years and allocated the 40 flights per hour for National without difficulty, was unable to reach agreement the last time because ambitious new airlines like New York Air insisted on more than established airlines were willing to give up. The Department of Transportation imposed a solution.

The scheduling committee now is trying to argree to a new allocation for April 26, when the Goldschmidt plan was to have taken effect. If Lewis imposes a delay, the committee will try to divide 40 flights per hour (exisiting rule); if he does not, the committee will try to divide 36 (Goldschmidt plan).

New York Air has made the game even more interesting by announcing a new schedlue that would require eight more flights per day than its present allocation.

Walt Coleman, director of the scheduling committee, said yesterday, "I think this is the most difficult situation we have looked at National Airport."

He said the airlines have filed 814 flight requests per day for a possible 640 positions under the exsisting rule and 746 requests for 522 positions uner the Goldschmidt rule.

There have been a number of other self-serving suggestions. Edwin I. Colodny, chairman and chief executive officer of USAir, recently proposed moving Eastern Airlines shuttle flights and New York Air to Andrews Air Force Base. That would open up a lot of flights at National for USAir. He also proposed eventually closing National after facilities at Dulles are expanded. p

The Aircratf Owners and Pilots Association, the lobby for private planes, suggested this week that National be turned into a small-plane and commuter flight airport. "Our concern is retention of the airport," said spokesman Charles Spence. "Unless we reduce the noise, there will be added pressures to totally close the airport."

The airline industry is unable to speak with one voice. Eastern Airlines, for example, badly wants to use jumbo jets at National and has been willing to pay the price of losing a few slots to get that permission. Other airlines like Piedmont and USAir, which have small planes, are more interested in the number of flights.

A review will also doubtlessly reopenthe question of whether it is safe for jumbo jets to land at National, which has a relatively short main runway and restricted ramp and taxi facilites.