The long-term fix that Metro is seeking for its growing operating deficits remains as elusive as ever despite two days of speeches and back-room caucusing by area transit officials at Metro's annual policy conference at Fauquier County's Airlie House retreat center.

Metro officials had hoped last week's gathering would begin mapping out a joint "strategic plan" for the challenges of the coming five years. But it generated only tepid debate and adjourned two hours ahead of schedule, with Maryland, the District and Virginia agreeing to continue tackling their burgeoning subsidy bills in their own disparate ways.

Metro Board Chairman Joseph Alexander's efforts to build momentum toward a special areawide tax devoted to mass transit, from the start considered a longshot by many transit officials, were stopped with little ceremony when Maryland refused outright to help.

Still, the conference did mark a turning point of sorts for the 14-year-old transit authority. Prior meetings were dominated by battles over construction funding and schedules. Now, with opening days in sight for just under half the planned 101 miles of track, concern is shifting to how buses and rail cars will be kept moving through the 1980s.

"This is the first time that Metro has ever had the luxury to look beyond the current crisis," said General Manager Richard Page as the conference broke up. He expressed no surprise that no program was produced, saying that complex financial issues are not worked out quickly.

The meeting opened Thursday morning with Page briefing the group on his draft operating budget for fiscal 1983. It would push spending up 16 percent to $365 million and raise subsidy and debt service bills sent to Metro's eight jurisdictions by more than twice that rate -- a 35-percent increase to $206 million.

For the audience, well schooled in inflation's impact on transit, Page's news was sobering but not unexpected. But five years from now, with more inflation and a larger rail system, these bills may be remembered as small and manageable.

Metro staff projections show local payments reaching $344 million by fiscal 1987, almost double what Page is proposing for 1983. Everyone agrees that is too much. But the range of political philosophies and wealth of the member governments, not surprisingly, has produced an equally wide range of proposed solutions.

Republican-dominated Arlington, for instance, stresses lowering costs and raising fares to make the system more self-supporting. Other governments -- heavily Democratic D.C., for instance -- call that unrealistic, arguing that transit is a public service that benefits everyone.

The key is stopping the downward slide of the role that fares play and lining up a dependable source of revenue to pay the subsidies, they say.

That process began in earnest two years ago, when President Carter signed the Stark-Harris bill authorizing $1.7 billion to continue rail construction after the current primary source -- "trade-ins" or credits for cancelling interstate highway projects -- runs out. Metro hopes to begin drawing on the new money in fiscal 1983.

But the legislation says Metro can only do so if Maryland, Virginia and D.C. arrange "stable and reliable" sources of revenue to cover operating subsidies and debt payments. The bill does not spell out what "stable and reliable" means, and D.C. and the two states have followed separate paths. Federal officials will decide next year whether the three have complied.

At present, Maryland is the most advanced. State legislators passed a law under which the state picks up about three-quarters of Montgomery and Prince George's counties' shares of the Metro subsidies and debt service.

In the D.C. City Council, meanwhile, a law is pending to put vehicle registration fees and excise taxes, traffic fines, parking meter fees and assorted other revenue sources into one pot devoted to transit. This is designed to cover all of D.C.'s subsidy payments.

In July 1980, Virginia inaugurated a 2-percent gasoline tax for transit which will rise to 4 percent next July. Even then, however, revenues generated will cover only about 30 percent of northern Virginia's subsidy bills. Board chairman Alexander and other Virginia officials say that is simply not enough.

Predictably, then, what pressure there was for a regional tax (variously suggested for gasoline, sales or payrolls) came mostly from them, although D.C. council members have also backed the idea with less urgency. In the final session of last week's meeting at Airlie, D.C. delegates said they would go along with such a tax if the two states did. But Maryland rejected it flatly.

"Maryland has met its obligations to establish a stable and reliable source of revenue," said Lanny Davis of the Washington Suburban Transit Commission, which links Montgomery and Prince George's counties. " . . . We do not favor any regional tax."

With that question settled, the gathering adopted with only a few minutes' discussion a bland resolution calling for completion of the full 101-mile rail system, high ridership and more federal funding. It made no mention of the local subsidy question, the meeting's major talking point.