outflow valve

outflow valve

A valve in the aircraft pressurization system that controls the pressure inside the cabin by controlling the amount of air allowed to flow out of the cabin. It is a type of pressure maintenance valve.
References in periodicals archive ?
After getting the outflow valve to close enough to maintain a cabin altitude less than 10,000 feet, the flight was completed by transiting at 15,000 feet.
To illustrate the model, let's take a simple example consisting of a fluid tank with an intake valve and an outflow valve.
If an outflow valve that should be closed is accidentally left open, media can leak to the environment without notice or until another part of the control system discovers the error.
The Air Accident and Incident Investigation Board (AAIIB) of Cyprus could not conclusively determine the causes of the incident, but indicated two possibilities: an electrical malfunction causing the opening of the outflow valve, or the inadvertent opening of the aft service door.
Other Honeywell products on the G550 include the RE220 auxiliary power unit (APU), environmental control system, cabin pressurization control system with new thrust recovery outflow valve (TROV) and lighting.
The Air Accident and Incident Investigation Board of Cyprus could not conclusively determine the causes of the incident, but indicated two possibilities: an electrical malfunction causing the opening of the outflow valve, or the inadvertent opening of the aft service door.
In the process, the flight engineer shut off the aft outflow valve to allow the fumes to remain in the jet, but the crew still could not locate the source.
Iordanis Spyroglou, a metallurgical and mechanical engineer working for the Greek Air Force, said that on examining the indicators of the two outflow valve manual switches -- salvaged from the plane wreckage -- he found that one of the switches (the right one) was on.
The flight engineer left the flight station to check the malfunctioning outflow valve in the back of the aircraft, and the off-duty FE took his place.
According to the accident investigation report released in 2006, the outflow valve on flight ZU522 was in the manual position before takeoff, which did not allow the cabin to pressurise.
This allowed it to swing down and strike the forward outflow valve and another fiberglass duct, which in turn sheared off the top of the vacuum pump.
The witness again referred to the outflow valve, which was incorrectly left in the manual position during takeoff, which led to the aircraft not pressurizing during flight.