Perpetual American Federal Savings and Loan Association expects to lose about $5 million this year, the two top executives of the McLean-based S&L recently told Savings and Loan News magazine.

That's almost $2 million more than Perpetual American lost in 1981, a year the industry described as the worst in 40 years.

That Perpetual should go public and project its losses so far in advance is rare for a mutual association. Unlike S&Ls in which the public owns shares, mutual associations aren't required to report their earnings except to regulatory authorities.

And even then, only the results of federally insured S&Ls are made available to the public.

Taken in the context of the industry's continuing losses and mergers, Perpetual American's disclosure may be more than unusual. It may be a harbinger of heavier losses for local S&Ls as well as the entire industry.

Figures provided by the Federal Home Loan Bank Board show that the 45 federally insured S&Ls in metropolitan Washington lost more than $100 million last year. And some local S&L officials say it is unreasonable to expect this year to be any better.

Actually, Perpetual American had projected a much bigger loss of $16 million this year, but the firm's officials moved to offset that possibility by selling the association's old headquarters building in downtown Washington. The sale of the building at 11th and E streets NW is expected to produce a gain of $11 million, according to Perpetual American Chairman Thomas J. Owen and President William Sinclair.

Without the benefit of that sale, however, Perpetual American's projected loss for the year was roughly five times that of its 1981 loss of just over $3 million.

Several local S&Ls lost considerably more than $3 million last year, and a loss rate five times -- or even three times -- as great would put some perilously close to zero net worth.

Perpetual American's projected $5 million loss may not be as firm today as it was earlier, Sinclair says. "The jury is still out because we've had two mergers -- a voluntary one and an involuntary one," he noted.

"All I can say now is that I'm optimistic because of the [recent] turnaround in [interest] rates."

It's too early to tell whether the trend toward lower interest rates will be of much help to S&Ls this year, but clearer signals should be apparent within the next two or three weeks, Sinclair believes.

Meanwhile, other S&Ls can be expected to pile up losses equal to last year's, if not greater. Several area associations are reported to have serious earnings problems.

Unlike Perpetual American, however, other S&Ls refuse to discuss projected losses. "Let's put it this way: We won't operate at a profit this year," said Dewitt Hartwell, president of Columbia First Federal, the District's second-largest S&L. And that is "due to the cost of money and not to bad management," Hartwell emphasizes.

The high cost of money is likely to be a more troublesome problem for most of Perpetual American's competitors in metropolitan Washington. Whereas Perpetual American has a whopping 40 percent of its deposits in low-yielding passbook accounts, the industry as a whole has only 18.7 percent of its deposits in regular savings accounts.

The decline in interest rates has buoyed officials here, however, and the outlook for some may not be as grim as it appeared to be two months ago. Nonetheless, the situation is "kind of muddied," says John Stadtler, chairman of National Permanent Federal, the District's largest S&L.

"Until you come down to the end, there's just no definitive answer you can give," said Stadtler. Trying to reverse a losing trend brought on by high interest rates is "like trying to turn the Queen Elizabeth around," he added.

National Permanent lost more than $16 million last year.

"Just because the prime [interest rate] has gone down about three points doesn't mean your costs are going to go down as rapidly," he said.

Although he projects a loss this year, one S&L official criticized competitors for not being more resourceful.

"They need to go out and do some of these creative things such as selling all those low-interest [mortgage] loans," he suggested.

What's more, he said, some S&Ls would be better off if they closed some offices or cut back on headquarters space for which many are paying premium rental rates.

"When you start to pay $25 to $30 a square foot to house a computer, it doesn't make sense. They ought to do like Perpetual and get the hell out," the official suggested.

Perpetual American acquired Washington-Lee Federal of McLean in a unique merger approved in June by the bank board and changed its charter. But even before it became a Virginia S&L, Perpetual American moved its operations division to Alexandria.

While other S&Ls may not be in position to follow Perpetual American's lead, slashing operating costs is an option that is available to most.