{
  "$type": "site.standard.document",
  "description": "A method of controlling an aircraft gas turbine engine cooling system (20). The cooling system comprises a heat exchanger (22) having a first fluid path (24) through which fan air can flow, and a second fluid path (26) through which relatively hot compressor air can flow. The cooling system (20)…",
  "path": "/patents/971557",
  "publishedAt": "2014-08-06T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "B64D33/02",
    "ROLLS ROYCE PLC [GB]"
  ],
  "textContent": "A method of controlling an aircraft gas turbine engine cooling system (20). The cooling system comprises a heat exchanger (22) having a first fluid path (24) through which fan air can flow, and a second fluid path (26) through which relatively hot compressor air can flow. The cooling system (20) further comprises a valve (30) configurable between an open position corresponding to a first operating mode, in which fan air flows through the first path (24) to cool the compressor air in the second path (26) to a lower temperature, and a closed position corresponding to a second operating mode, in which fan air flows through the first path (24) at a reduced rate, or not at all, such that the compressor air in the second path (26) is cooled to a lesser extent, or not at all. The valve (30) is operated in the first mode when the aircraft determined to be in a descent mode, or when turbine entry temperature (T30) of the gas turbine engine is above a predetermined amount. Otherwise, the valve (30) is operated in the second mode.",
  "title": "Method of controlling a cooling system"
}