Draft NASA Constellation Program Management Directive Regarding Use of English Units of Measure

"3. RATIONALE: This directive defines and communicates a consistent approach to the use of engineering units throughout CxP. The program conducted an extensive and detailed effort to implement a primary SI units based system for design, analysis, test and operations while allowing English units for most of the hardware. This effort looked at various implementation strategies and worked the implementation details to the point of having workable implementation plans in all the projects. However, the cost estimates to achieve these plans significantly exceeded the resources that could be made available in the critical years. Therefore, given budget constraints and the need for consistent practice of units throughout the CxP lifecycle to minimize risks and to achieve mission success, the program is revising its previous management directive to a primarily English units based program with limited usage of SI as defined in the MD. This MD constitutes the basis for the waiver to NASA policy directing the usage of SI." Draft NASA Constellation Program Management Directive Regarding Use of English Units of Measure

NASA OIG Assessment of NASA's Use of the Metric System, G-00-021

"Following the loss of the Mars Climate Observer, the NASA Office of Inspector General initiated a review of the Agency's use of the metric 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 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."

NPD 8010.2E Subject: Use of the SI (Metric) System of Measurement in NASA Programs

"b. All new programs and projects covered by NPR 7120.5 shall use the SI system of measurement for design, development and operations, in preference to customary U.S. measurement units, for all internal activities, related NASA procurements, grants, and business activities. Exceptions to this requirement may be granted by the NASA Chief Engineer based on program/project recommendations by the responsible Mission Directorate Associate Administrator where use of SI units is demonstrated to be impractical, adds unacceptable risk, or is likely to cause significant inefficiencies or loss of markets to U.S. firms. Special emphasis shall be placed on maximum use of SI units in cooperative programs with international partners."

Keith's note: NASA claims that it wants to have meaningful international participation in the implementation of VSE/ESAS yet it walks away from the system of weights and measures used by the majority of the people on this planet. Moreover, this decision clearly seems to fly in the face of established NASA - and Federal - policy.

NASA Gets Heat For Ditching Metric System on New Shuttle Replacement, Popular Science

"The commercial spaceflight sector, who had hoped to use the Orion and Ares systems for a variety of missions, is not too happy. "We in the private sector are doing everything possible to create a global market with as much commonality and interoperability as possible. But NASA still can't make the jump to metric." Mike Gold of Bigelow Aerospace told New Scientist."

NASA Inspector General's Assessment of NASA's Use of the Metric System, G-00-021 (2001)

"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 SI, the protracted period during which NASA uses mixed metric and English systems may further increase costs and risks for NASA programs."

NASA Finds The Metric System Too Hard To Implement for Constellation, Earlier Post

"NASA claims that it wants to have meaningful international participation in the implementation of VSE/ESAS yet it walks away from the system of weights and measures used by the majority of the people on this planet. Moreover, this decision clearly seems to fly in the face of established NASA - and Federal - policy."

NASA criticised for sticking to imperial units, New Scientist

"NASA recently calculated that converting the relevant drawings, software and documentation to the "International System" of units (SI) would cost a total of $370 million – almost half the cost of a 2009 shuttle launch, which costs a total of $759 million. "We found the cost of converting to SI would exceed what we can afford," says Hautaluoma."

Keith's note: That's a goofy answer. Why couldn't ESMD have simply directed that things be done in metric in the first place - in compliance with NASA's own regulations (note the OIG report from 2001 years before Constellation was even started). That way there'd be no "conversion" cost.

Oh yea, interesting how Grey just told us what a shuttle launch "costs".

source: http://www.nasawatch.com/archives/2009/06/more_poor_excus.html

source: http://www.nasawatch.com/archives/2009/06/nasa_finds_the.html