Search results
Results From The WOW.Com Content Network
Length. For measuring length, the U.S. customary system uses the inch, foot, yard, and mile, which are the only four customary length measurements in everyday use. From 1893, the foot was legally defined as exactly 1200⁄3937 m (approximately 0.304 8006 m). [13] Since July 1, 1959, the units of length have been defined on the basis of 1 yd = 0 ...
The operational success of a "Test Shop" program set up at March AFB, California, on 15 September 1957, led to the establishment of the base-level Precision Measurement Equipment Laboratories providing the Air Force with a complete calibration system that could handle the increasingly stringent measurement needs of the new missile and aircraft ...
The United States and the Metric System (LC 1136) nist.gov Archive.org; The Metric System in the United States Archived June 11, 2017, at the Wayback Machine; A Metric America: A Decision Whose Time Has Come on nist.gov Archive.org; Metric Conversion Act of 1975 on nist.gov Archive.org; www.us-metric.org—U.S. Metric Association (mirror link)
The imperial and US customary measurement systems are both derived from an earlier English system of measurement which in turn can be traced back to Ancient Roman units of measurement, and Carolingian and Saxon units of measure. The US Customary system of units was developed and used in the United States after the American Revolution, based on ...
The imperial system has a hundredweight, defined as eight stone of 14 lb each, or 112 lb (50.802 345 44 kg), whereas a US hundredweight is 100 lb (45.359 237 kg). In both systems, 20 hundredweights make a ton. In the US, the terms long ton (2240 lb, 1 016.046 9088 kg) and short ton (2000 lb; 907.184 74 kg) are used.
A Precision Measurement Equipment Laboratory (PMEL) is a United States Air Force (USAF) facility in which the calibration and repair of test equipment takes place. This practice is also known as metrology: the science of measurement. Metrology is defined as the science of weights & measures, while a PMEL is the place where technicians perform ...
A 1951 USAF resolution test chart is a microscopic optical resolution test device originally defined by the U.S. Air Force MIL-STD-150A standard of 1951. The design provides numerous small target shapes exhibiting a stepped assortment of precise spatial frequency specimens. It is widely used in optical engineering laboratory work to analyze and ...
Aeronautical Systems Center. The Aeronautical Systems Center (ASC) is an inactivated Air Force product center that designed, developed and delivered weapon systems and capabilities for U.S. Air Force, other U.S. military, allied and coalition-partner warfighters. ASC formed in 1961, and over its lifetime it managed 420 Air Force, joint and ...