Delays in B-52 Modification May Keep U.S. Within SALT II Limits

Modification work on a B-52 bomber that would put the United States above the limits of the SALT II arms accord has been delayed, probably until late December, Pentagon sources say.

The sources, who spoke on condition of anonymity, said the modification work on the plane--the 131st B-52 to be so modified--has been moving more slowly than expected because of technical problems.

Nevertheless, the delay raises the possibility that President Reagan will fail to make good on his decision to abandon the second strategic arms limitation treaty before a hoped-for summit meeting this year with Soviet leader Mikhail S. Gorbachev.

Soviet Violations Charged

Reagan announced in May that he was preparing to abandon the 1979 SALT II accord because of Soviet violations of the pact. At the time, Reagan said he had ordered that two old Poseidon submarines be dismantled to remain in compliance with the accord through the summer. But he said he would allow the Air Force to continue modifying its B-52s to carry cruise missiles.

Cruise missiles are low-flying, unmanned jets that hug the ground to avoid radar. They can carry either conventional or nuclear warheads.

Until Reagan’s decision last May, the United States and the Soviet Union had pledged to abide by the terms of the pact even though the accord was never ratified by the Senate. Among the restrictions is a limit of 1,320 on the number of multiple-warhead missiles that each side can possess.

For the United States, a bomber equipped with cruise missiles counts against that limit. The modification of the 131st B-52 to carry cruise missiles--unless offset by the retirement of other submarine- or silo-based missiles--would push the United States over the 1,320 limit.

No Schedule Revealed

The Pentagon has never publicly revealed a precise schedule for completing modification work on the 131st bomber beyond saying it would occur toward the end of the year.

The sources confirmed a report in Friday’s editions of the New York Times that there is a possibility of a delay until the end of the year.

The Reagan Administration maintains that the SALT II accord was flawed from the start because it did not require deep reductions in nuclear weapons, and that the Soviets have violated it through such actions as deploying a new, SS-25 land-based missile. Critics counter that the United States should not break out of the agreement when there are still prospects for negotiating a new arms control treaty.