In its first comprehensive financial proposal, the National Football League Players Association handed negotiators for the NFL owners yesterday a plan under which players would be paid from a trust fund that would disburse 70 percent of its money on the basis of seniority and 20 percent on the basis of performance on the field.

The remaining 10 percent of the money in the fund, which would draw its income from 55 percent of gross revenues from all NFL sources, would cover costs of administering the fund, salary adjustments for previously negotiated contracts and severance pay for players.

The NFLPA made its proposal in a three-hour bargaining session yesterday that its executive director, Ed Garvey, described as "the most positive session we've had."

Jack Donlan, executive director of the NFL Management Council, the league's labor negotiating arm, said he would study the proposal and have a response when negotiations are resumed in Washington today.

"They know how we feel about percentage of the gross," said Donlan, who has strongly opposed that concept. "That's going to be a big hurdle. But sometimes even when you don't like something you can find the germ of an idea in it that can take you down a different path."

Despite the gap between the two sides on the percentage of gross revenues concept, yesterday's session was free of the rancor and bitterness that has characterized some of the earlier meetings.

Detroit Lions linebacker Stan White, a member of the negotiating team, said, "for the first time there was some real give and take. We were able to get our views across to them."

In its proposal yesterday, the players association suggested that the trust fund from which players be paid be administered by a corporate trustee, probably a bank, to be chosen by the management council. This was to counter council objections that an earlier union proposal, that the fund be jointly administered by the league and the union, might be illegal, Garvey said.

As envisioned in the union proposal, 70 percent of the money in the fund would be paid out in base salary, which would be computed according to a point system with players being awarded points based on years in the league.

Almost 8 percent would be awarded on the basis of downs played with offensive, defensive and special team units sharing equally in that pool.

Playoff and Super Bowl teams would share 4.5 percent of the money in the fund under a formula that would increase the rewards with each playoff victory. Twenty percent of the total money in the playoff pool would go to the two Super Bowl teams with the winning team getting 60 percent of that pool and the losing team 40 percent.

The proposal would set aside 4.15 percent of the money in the fund to be divided among the league's top five offensive, defensive and special team units as determined by 18 separate statistical categories. Individual players would be compensated in this category on the basis of downs played.

Players in each conference would select 40 Pro Bowl participants by secret ballot, and those players selected would divide 1.4 percent of the money in the trust fund. Players on the winning Pro Bowl team would share 60 percent of the pool, players on the losing team 40 percent.

Additionally, the NFL players would select the league's 272 top individual players, apportioned by position, to share 1.7 percent of the money in the trust fund. In each case, the players would not be allowed to vote for members of their own team.

Garvey said he could not give a statistical estimate on exactly how the proposal would affect current salaries other than to say that 97 percent of the players' salaries would increase. The union estimates the current average NFL salary is $83,000; management says it is closer to $90,000.

The current contract between the management council and the NFLPA expires July 15, and both sides say they would like to have an agreement by then. Both Garvey and Donlan said any players not under contract by then would no longer be able to negotiate individually with the clubs but would have to negotiate through the NFLPA and the management council.