FLAME PROTECTION SEALS FOR GAS TURBINE ENGINES

Gas turbine engines include an engine core having compressor, combustor, and turbine sections arranged within an engine casing. A transfer tube (404) is arranged on an exterior of the casing and configured to define a fluid conduit for fluid (410) to be transferred about the engine. A fitting (402) is connected to the transfer tube (404) and a seal assembly (406) is arranged between the fitting (402) and the transfer tube (404). The seal assembly (406) provides a fluid seal between the fluid conduit and an ambient environment (412) at a connection between the fitting (402) and the transfer tube (404). The seal assembly (406) includes a primary seal (414) arranged in a gap (413) between the fitting (402) and the transfer tube (404) and a secondary seal (416) arranged in the gap (413) between the primary seal (414) and an ambient environment (412). The secondary seal (416) is configured to expand into engagement with the fitting (402) and the transfer tube (404) when exposed to temperatures of at least 800 °F.