To contain and isolate engine fires, civil aviation regulations require that aircraft enclosures be sealed from the rest of the aircraft and be "fireproof." As outlined in FAA Advisory Circular AC 20-135 [1], a structure is considered fireproof if it can withstand a 1093°± 83°C flame for a minimum of 15 minutes, while still fulfilling its design purpose and resisting flame penetration (AC 20-135 also provides minimum requirements for flame size and heat flux density). Given that this temperature is greater than the melting point of aluminum alloys, aircraft designers have generally met this fireproof ness requirement through the use of titanium or steel enclosures or via the incorporation of significant insulating/ shielding elements. These approaches, however, result in both increased structural cost and weight. A promising approach to addressing both problems is the application of advanced composite materials.
展开▼
