inertia switch[i′nər·shə ‚swich]
A switch that is actuated by an abrupt change in the velocity of the item on which it is mounted.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
An electrical switch that is actuated by the sudden acceleration of an aircraft. Inertia switches are used in emergency locator transmitters, which get activated when the aircraft decelerates rapidly during crash landings.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved