Reversers run with Bleed Air switch OFF?
From the Aerowinx Forum, messsage by Ian Riddell: …There are a number of valves which are closed when you push the overhead BLEED air switch (some with funny names such as HPSOV, PRV, and PRSOV). These three valves are in-line and are in this order (from the engine). During Reverse Ops, however, the HP and PRV valves open automatically when the reverse levers are pulled up/back, to allow engine bleed to get to the reverser. Something *similar* happens with the NAI system, too. Please note: the bleed system is smart enough to recognise an overheat, however, and will not open these valves if such a condition exists (or has existed, I think). Availability of reversers is affected, however, if you shut down that particular engine completely. We (engineers) can run the reversers on the ground without running the engine, I’m glad to say, by using APU bleed air. We pull the start switch for the engine concerned (and do a few other maintenance-type things) which allows bleed air to reverse f
