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Old 3rd July 2025 | 05:11
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NSEU
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Joined: Feb 2004
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From: Australia
Originally Posted by Someone Somewhere


As for vacuums... remember it can't be 3000PSI of suck; suck isn't a thing. It's ambient pressure pushing in. At sea level you have ~15PSI of air pushing the fuel into the pump; at altitude it might be 7-8PSI. You don't want a near-perfect vacuum on the fuel because then it starts to boil on you.
Makes sense, that's why I was questioning the lack of ambient air (being pushed in). The NACA scoops should both allow air to get in and provide a small positive pressure above ambient. The wing photos I've seen don't seem to show NACA scoops. The wing appears to be clean from the overpressure valve to the wingtip, contrary to the vent system graphic.

It looks like there isn't a dedicated NGS motor controller; instead it is powered from either the HYD L CMSC or the cabin air compressor R2 CMSC.
Yes, not sure. I found a table online of what system was on what branch of the electrical system, but the listings were L1 ~L8 and R1~R8. The NGS was on R4. I can't relate that to anything in the diagram or other diagrams I have.

Thanks.

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