devices, instead deferring to the new AIAA Standard for Ordnance, AIAA-S-113-2005. Clampbands and  retention cables are also included in a new section. Although these hardware items were used prior to  1988, no considerations or requirements were provided in the former MMA specification.  Bearinu stresses for new steel materials  The development and increased use of hybrid bearing material combinations such as Si3N4 (silicon  nitride) balls and M62 (bearing steel) races required a certain level of attention. Allowable stress levels in  prior documents only corresponded to 440C, but the new standard recognizes and provides requirements  for 52100, M50, and M62 steels as well. Varying levels of allowable stresses for all of these materials are  provided for quiet-running as well as non-precision, short duration applications.  Life testinu for lonu life mechanisms  In one of the more significant changes, and one that easily generated the most discussion and debate by  the COS, life test requirements were revisited, motivated by the increasing duration of today’s missions as  compared to those typical of two and three decades ago. A distinction is now made between “low-cycle  MMAs” (such as release devices, spring driven “one-shot” deployables, etc.) and “high-cycle MMAs”  (such as solar array drives, momentum wheels, tracking gimbals, etc.), with different corresponding life  requirements now given for each.  Run-in testinu modifications  Another moderately noteworthy change in the testing requirements involves run-in testing. Run-in testing  can be expressed in terms of cycles or a percentage of expected life. A slight reduction in the potential  number of minimum run-in cycles has been incorporated. This was a result of some common sense being  applied, particularly in the area of release devices, or other “one-shot’’ MMAs. It is generally accepted that  the design life for these types of mechanisms is about 50 cycles, given the number of expected tests on  the ground, plus on-orbit use(s), plus margin. The current minimum number of required cycles in the AlAA  standard brings it closer to correspondence with the minimum percentage of life for these types of MMAs.  “Informative” annex on static toruue/force maruins at different coordinate Doints  This was the subject of a paper at the 37th Aerospace Mechanism Symposium by R. W. Postma of The  Aerospace Corporation, and it was chosen to be included as an informative appendix, not necessarily  subject to contractual compliance. This section describes the basic methodology overview for MMAs that  have drive forces (or torques) and resisting forces (or torques) applied to mechanical elements that do not  all move at the same velocity. A common example would be the ratio of the rotation of a jackscrew  relative to its translation (e.g., rad/in).  Summary  US. Air Force (and effectively NRO) policy is swinging back to previous practices of requiring the use of  specifications and standards. Subsequently, several subject matter documents have been reviewed,  edited, and updated. Incorporation of those documents has started in the proposal phase of new  acquisitions. One of the first new standards to be developed under these new guidelines is the AlAA  Standard, “Moving Mechanical Assemblies for Space and Launch Vehicles,” AIAA-S-114-2005. It is  based on the former MMA military specification, but reorganized and technically scrutinized by a  committee of industry experts to reflect the current state of the art in designing, fabricating, and testing  space mechanisms. This standard will begin to be required as a compliance document for future Air  Force space acquisitions, and can be purchased through the AlAA website.  110