Trident II:

Reductions to MK-6 Guidance System Inventory Objectives May Be Possible

NSIAD-94-192: Published: Jul 6, 1994. Publicly Released: Jul 21, 1994.

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Louis J. Rodrigues
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Pursuant to a congressional request, GAO reviewed the Navy's rationale for procuring spare MK-6 guidance systems for the Trident II submarine's D-5 missile, focusing on the: (1) Navy's total program inventory objective; and (2) effect of reducing the inventory on the missile's overall reliability.

GAO found that: (1) the Navy based its inventory objective on maintaining the D-5 missile at a high level of readiness throughout the program's life; (2) the Navy calculated its program needs using methods that provided it with the highest number of MK-6 spares that might be needed at any time; (3) the Navy believes it does not have the experience to accurately predict its spare parts needs for a missile program whose expected life exceeds 20 years; (4) reducing the number of MK-6 spares on board each patrolling submarine from six to three would reduce operational readiness by only 3 percent; (5) reducing the number of MK-6 spares on board each patrolling submarine to four would reduce readiness by only .66 percent; (6) no Trident patrol has ever had more guidance system failures than it had spares; (7) operational readiness reductions would have a minimal effect on the D-5 missile's reliability; and (8) the spare parts reductions savings could range from $106 million to $159 million and current readiness and reliability levels would be reduced for only a few years.

Recommendations for Executive Action

  1. Status: Closed - Not Implemented

    Comments: The DOD response to the recommendation stated that it would use the results of a Nuclear Posture Review to determine whether the Trident II readiness goals remain appropriate. That review did not indicate a significant reduction in readiness goals.

    Recommendation: The Secretary of Defense should consider whether some slight reductions in the operational readiness and reliability goals established in the 1986-1987 time frame during the Cold War era are acceptable, in view of the threats that exist in the world today since the breakup of the Soviet Union.

    Agency Affected: Department of Defense

  2. Status: Closed - Not Implemented

    Comments: The recommended reduction in spare guidance systems to be procured was dependent on the Navy determining that it could reduce its readiness goals. Because readiness goals are not being significantly reduced, this recommendation becomes academic. Additionally, while the Senate Appropriations Committee recommended that the number of spares be reduced and cited the GAO work as justification, that recommendation was not adopted by the conferees.

    Recommendation: If these reductions are acceptable, the Secretary of Defense should reduce the number of additional MK-6 guidance systems to be procured.

    Agency Affected: Department of Defense


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