WASHINGTON — The United States should halt further flight tests of the Navy's new Trident submarine-launched nuclear missile if Washington wishes to avoid complications in negotiating strategic arms reductions with Moscow, Senate Republicans were told Monday.
The analysis, prepared by the Congressional Budget Office for GOP members of the Senate Armed Services Committee, was released as the Pentagon prepared the Trident 2 missile for its second flight test as early as this month. It may accelerate efforts under way in the House and Senate to lower the limit on the number of warheads with which the missile is tested.
The report notes that if the Navy proceeds with plans to test the new missile with 12 warheads--four more than the missile has carried in the past--Washington may be credited with more firepower than it actually has in the long-range arms negotiations that will follow next month's expected U.S.-Soviet agreement to ban ground-launched intermediate-range missiles.
However, the budget office said it is unlikely that the Soviets would agree to count the Trident 2 as a missile carrying only eight warheads if the United States continues its test program with greater numbers.
"If further flight tests of the 12-warhead version go forward, either the United States or the Soviet Union could feel disadvantaged," the budget office concluded. "That . . . could make negotiation more difficult."
Under the 1979 Strategic Arms Limitation Treaty, the superpowers agreed to calculate the size of their arsenals by assuming that each missile carries the maximum number of warheads that had been carried in flight tests.
If the superpowers adopt the same so-called "counting rules" in the forthcoming Geneva negotiations, the United States could be forced to count 400 to 900 "phantom warheads" that were not deployed on the Trident.
The United States already has tested one Trident 2 missile, designed to carry 12 warheads, with a payload of 10. Outgoing Defense Secretary Caspar W. Weinberger has advocated launching the next test missile with its full complement of warheads.
But several lawmakers have urged Reagan not to test the new missile with all 12 warheads until the superpowers have agreed on new counting rules for the next round of strategic arms talks.
Last Wednesday, legislators won assurances from Frank C. Carlucci, Weinberger's designated successor, that the Pentagon will delay the next Trident test at least until after the Senate has had hearings on the matter. Those hearings are expected by early next week.
If the planned second flight test of the Trident is scuttled, the missile development program would be delayed "by at most a few months," the budget office said. The United States could use the time to modify the new missile so that it would carry only eight warheads--an "approach that could increase costs," it added.
Finally, the budget analysts said that the Pentagon could resume development of the 12-warhead Trident 2 as late as 1990 and still put the weapon to sea by 1993, its scheduled deployment date.
Although the United States would have difficulty persuading the Kremlin to credit the Trident missiles with only eight warheads if it continues its testing, analysts said, the Soviets may be willing to discount the one test concluded to date because the missiles used are developmental, rather than production versions.