The U.S. Navy kept buying shark repellent for its pilots for 12 years after experiments showed the substance did not work, the Senate was told yesterday.

Sen. Lee Metcalf (D-Mont.), said tests in California in 1962 showed that the soluble cakes or dye and copper acetate offered no protection to downed fliers. But the Navy continued to buy them until February, 1974.

Metcalf said an official description of the so-called "shark chaser" called it a sack of chemicals similar to a large cloth tea bag, which formed a protective zone around the user.

But a Library of Congress notation attached to an exhibit of the repellent, the senator said, stated that the shark chaser was of little value in repelling sharks.

"Under test conditions sharks have swum through its cloud of dye and consumed the package itself," the notation said.

Metcalf noted that a report by the Office of Naval Research said "a mounting body of evidence has now conclusively demonstrated that shark chaser has no significant deterrent value against most dangerous sharks."

Metcalf asked, "Why, then, have Navy air crewmen been equipped with a large cloth tea bag, having all the shark repellent effects of a large cloth tea bag?"

He said the Navy spent about $340.000 for shark repellent from November, 1969, to February, 1974, after which purchases were stopped.