Reportedly unhappy about President Reagan's two nominations to the National Transportation Safety Board, seven members of the Senate Commerce Committee are cosponsoring legislation that would beef up the professional requirements for membership on the board.

The legislation--whose sponsors including committee Chairman Bob Packwood (R-Ore.) and ranking minority member Howard W. Cannon (D-Nev.)--would require members of the board to have expertise in the fields of accident reconstruction, safety engineering, transportation safety or transportation regulation.

The National Transportation Safety Board is a five-member independent agency with the mission of promoting transportation safety by conducting independent accident investigations and by formulating safety improvement recommendations in aviation and surface transportation matters.

This week, for instance, the board reported the results of its independent investigation of the operation of the air traffic control system during the first two months following the controllers strike. The board pronounced the system safe, but warned about some potential future dangers, including controllers' stress and fatigue.

Senate sources say the bill is a direct outgrowth of the legislators' concern that neither of the president's two recent nominees to the NTSB have any professional experience in transportation or transportation safety.

Sources say that James E. Burnett Jr., President Reagan's nominee to head the board, nevertheless is expected to be confirmed by the Senate. Burnett, 34, is an attorney from Clinton, Ark. He was Vice President George Bush's first delegate during his presidential race, sources said.

But the White House reportedly has been informed that the president's nomination of Eugene Lipp, a California consultant, to be a member of the board is in trouble. Senate Aviation subcommittee Chairman Nancy L. Kassebaum (R-Kan.) is said to be very concerned about Lipp's "lack of qualifications" to be a member of the agency. He has had a variety of jobs, including membership on the California Alcoholic Beverage Control Appeals Board from 1971 to 1978, and has been involved in Reagan and California Republican activities.

Although some have raised objections that Lipp hadn't gone to college, his opposition appears to stem more from his lack of a background in transportation. "People can be very well-qualified without going to college," said Charles Spence, a spokesman for the Aircraft Owners and Pilots Association. The concern of the aviation group is Lipp's lack of transportation knowledge, he said, adding, "It's like putting a non-doctor in the operating room."

John L. Baker, president of the 255,000-member group, testified against Burnett at his confirmation hearings last month. Baker said the AOPA has nothing against Burnett personally but found him "completely lacking in any credential whatsoever for one of the most technical jobs in the administration . . .

"The United States cannot afford to see the National Transportation Safety Board become the parking place for political appointees," Baker said.

But NTSB Chairman James B. King, whose term expires at the end of the month, said yesterday he doesn't think all five members should possess technical expertise. Right now, that is required of two of the five members. "God save us," he said. "The NTSB has plenty of technical expertise" in the staff. He said an ideal board member would be someone intelligent, willing and capable of exercising judgment and willing to work hard. "Many times, I find technical people too narrow," he said.

A different view was expressed by a former Federal Aviation Administration official. He said the influence of board members on NTSB staff is very important, and that unqualified board members make less-than-rational decisions and recommendations.