Abstract :
USE of electric power in aircraft has grown with each succeeding year. Aircraft have become larger, and with each succeeding increase in size new and greater demands have been made for electric power. To date these demands have been met magnificently by 12-volt and 24-volt d-c systems, and there seems even reason to suppose that these systems will be in use for a long time to come. However, there is a transmission-weight penalty for a 24-volt system on large airplanes, particularly when the total load is high. Therefore, with an eye to the very large planes of the future, the aircraft industry has been fostering the development of two new electric systems, namely, a 115-volt d-c system, and a 208-volt three-phase 400-cycle system. Either of these two proposed systems will reduce greatly the weight of the electric wiring, and each system has its own special merits.
