RPM is the acronym used for revolutions per minute. It measures the number of revolutions completed in one minute around a fixed axis, giving the speed of a mechanical component. It is commonly used to describe the performance of automobile engines.
Like most ballparks built from the 1990s onward, Safeco Field is a 'retro-modern' style ballpark that incorporates many of the features of ballparks built in the 1950s and earlier with modern amenities.
Fort Concho was one of the best preserved frontier forts in the United States in 1990. It has been declared a National Historical Landmark. In 1940 the United States War Department selected San Angelo as the location for Goodfellow Air Field. In 1958 the air force changed its function from air training command to United States Air Force Security Service, offering intelligence training courses to all branches of the military.