Mountain Time Zone is generically called Mountain Time (MT). Specifically, it is Mountain Standard Time (MST) when observing standard time, and Mountain Daylight Time (MDT) when observing daylight saving time. The term refers to how the Rocky Mountains, which range from northwestern Canada to the US state of New Mexico, are located almost entirely in the time zone. In Mexico, this time zone is known as the Zona Pacífico (Pacific Zone). In the US and Canada, the Mountain Time Zone is to the east of the Pacific Time Zone and to the west of the Central Time Zone. In some areas, starting in
Standard Air Lines rail link at El Paso, Texas, to carry passengers farther east by train. This was the first regular transcontinental rail and air passenger to and from California. Standard Air Lines began business as a three-times a week passenger and express service between Los Angeles, Phoenix and Tucson. The initial fleet consisted of two Fokker airplanes (NC7713 and NC8011) and seven OX5-powered Eaglerock airplanes. Standard carried 61 passengers during it first month of operations in December 1927. Initially, aircraft left Los Angeles on Monday, Wednesday and Friday at 10:00 AM Pacific Time (PT), arrived in Phoenix at 3:30 PM Mountain Time