From: email@example.com (Greg Croydon) Organization: ViaNet Date: 03 Sep 96 01:16:57 References: 1
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Erico Oller Westerberg <firstname.lastname@example.org> wrote: >Re: Engine fire extinguishers...do they exist? >Could anyone tell me if there are any fire extinguishers mounted >inside or close to the engines in modern airliners? If there are >any - how do they work? Any special gas, different to those used >in regular fire extinguishers? You bet there are. All are part of a fire warning system, either temperature sensitive of optical. The engine area may be sensed by one or more heat-sensing loops, which are flexible, stainless steel tubes containing a single wire centred on a semi-conductor type material. The loops are connected to control units that monitor electrical resistance. As the loop is heated, its resistance decrease until, at a preset temperature, usually 500 degrees F, a nasty red light illuminates and bells/or robo-voices start telling you that you are having a bad day. The optical systems simply see bright lights in places they dont belong, but are less sophisticated and prone to reacting to sunlight seeping in, etc. Not used on modern aircraft. The extinguishant comes in many different varieties, the most notable being an interesting chemical that goes by the name, monobromotrifluoromethane (CBrF3). This agent is not corrsive, and its discharge does not necessitate cleaning of the engine or nacelle. Relase of the agent is done by the electrical firing of an expolosive discharge on the bottle containing the agent. Most aircraft systems will have two bottles per engine, with the capability of directing the agent to either engine. croy.