Following the loss of the Mars Climate Orbiter, the NASA Office of Inspector General initiated a review of the Agency’s use of the ma-yesterdayetric system. By law and policy, the metric system is the preferred system of measurement within NASA. However, our review found that use of the metric system is inconsistent across the Agency.
A waiver system, which was required by law and put into effect in 1991 to track metric usage and encourage conversion, is no longer in use. In addition, NASA employees are given little guidance on the Agency’s policy and procedures regarding use of the metric system.
As the United States continues its slow transition to the metric system, NASA must decide whether it wants to be a leader or a follower in the transition process. Both roles come with a cost.
If NASA chooses to push forward with the Agency’s use of the metric system, near-term costs may increase and short-term risk (both to schedule and mission success) may rise to some degree.
However, if the Agency follows the aerospace industry’s slow transition to the metric system, the protracted period during which NASA uses mixed metric and English systems may further increase costs and risks for NASA programs.
Based on our review, we made eight recommendations intended to realign NASA’s use of the metric system in accordance with national policy and Agency guidance.
We recommended NASA reexamine the Agency’s effort to convert to the metric system and develop a new approach for converting to the metric system, closely monitor technical interfaces between metric and English units, reinvigorate the metric waiver system, and use the metric system as the preferred system for interactions with the public.
Management Response: NASA management concurred with all of the report’s recommendations, except the recommendation that NASA use the metric system for interactions with the public.
In responding to this recommendation, management agreed to use metric units in all education programs and when communicating with the public about programs that use metric or hybrid metric/English units.
However, NASA’s Public Affairs Office plans to use English units of measurement when communicating about programs that use English units exclusively.
We continue to hold that since public law requires NASA to use metric units where economically feasible, the Agency should use metric units in all communications with the public.
