{
  "$type": "site.standard.document",
  "description": "A cover (40) system selectively allows a gas flow through a heat exchanger duct upstream of an exhaust duct (30) in an aircraft engine (10). A fluid is at a first pressure during an engine (10) operating condition and a second pressure lower than the first during shutdown. A plate (42) extends…",
  "path": "/patents/1388227",
  "publishedAt": "2026-04-29T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "F02C6/08",
    "PRATT & WHITNEY CANADA [CA]"
  ],
  "textContent": "A cover (40) system selectively allows a gas flow through a heat exchanger duct upstream of an exhaust duct (30) in an aircraft engine (10). A fluid is at a first pressure during an engine (10) operating condition and a second pressure lower than the first during shutdown. A plate (42) extends across the heat exchanger duct with aperture(s) extending therethrough. A closure is movable between an open position with gas flowing through the apertures (44) into the exhaust duct (30), and a closed position with the closure closing the apertures (44). A biasing member operatively connected to the closure closes the closure with a biasing force. During the engine operating condition, the first pressure creates a first force acting against and greater than the biasing force to urge the closure open. At shutdown, the second pressure creates a second force acting against and lower than the biasing force, the biasing force biasing the closure closed.",
  "title": "ENGINE EXHAUST REVERSE FLOW PREVENTION"
}