How many P2.5 Bleed Air Valves?
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The manual states that the P2.5 bleed air valves are used to stabilize the engine at lower power by releasing some of the compressed air instead of diverting it all into the combustion chamber. One closes at about 68% Ng, the other at 92%. Be aware that can be stuck open and prevent you from developing full power. Roger, understood.
Later in the manual, while describing the Jet Flap Pre-Swirl, it is mentioned that the flap replaces one of the P2.5 valves in favor of the cyclonic air flow.
I also can't see it on the tablet, so I'm guessing the mention of the second P2.5 valve is another Duke-ism that slipped in? Which valve do we still have, the one that closes at 68% Ng, 92%, or another value entirely?
This should be the v1.1 version of the manual.
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Less of a hold-over, and more of a generic statement on PT6A engines. I've added...
"The PT6A engine featured in this particular aircraft only has one P2.5 bleed valve. For more information, see the 'Jet-Flap Intake System (Pre-Swirl)” section of this manual below.'"
...to that section of the manual. The remaining P2.5 valve is the 92% high pressure valve.
