Article | Jul 01, 2010
"Sometimes, all I need is the air that I breathe and to love you," sang The Hollies in 1972. Nice sentiments, but wrong. You need air - not sometimes, all of the time. Many pilots scuba dive, always descending with a carefully checked tank, but many ascend without oxygen. Federal Aviation Regulation 91.211 states that a pilot of an unpressurized aircraft shall not operate from 12,500 to 14,000 feet for longer than 30 minutes without supplemental oxygen. Above 14,000 feet, oxygen has to be used by the crew, and above 15,000 feet it must be provided for everyone aboard.