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Brenchen

Few Questions about the Aircraft vs Addon

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Hi all, I am making this post on behalf of a friend of mine, also a keen NGX owner. Unfortunately, his English abilities are very limited, but have experienced some issues that he hasn't found answers for yet. So here I go, trying to translate exactly what he wrote:

  1. NGX Hydraulics: When the hydraulics pressure is completely finished, I realised the rudder do not flip to one side, and the flaps do not sag down. In PMDG 744, it was very clear. When you release all hydraulic pressure, the rudder immediately flip to one side while the flaps sag immediately. Not sure whether this is a bug? And will this be included in the SP1?
  2. NGX Drag: From what I heard, NG's overall drag should be greater than the Airbus's, this is specially clear during descend. The A320 series aircraft have small drag, when descending, we usually use some spoilers. But NG's drag should be greater, therefore under normal conditions, spoilers shouldn't need to be deployed. But everytime when I descend, I always finding myself deploying some amount of spoilers. When CI is 30, normally in summer, temperature are rather high, air density is small, normally speaking, the aircraft should have better deceleration performance, but everytime, I must deploy spoilers.
  3. NGX Brakes: Under normal conditions, the brakes should cool rapidly in-flight and slowly while aircraft is stationary. But one time, I experienced brake temp to be 10, with the yellow warning. I stopped for over 40 min parked, the brake temp reading remained. And due to that, the brakes malfunctioned. So I took it up to FL370 and cruised for an hour, finding the brake temp still remained. Please, may I ask, how should I address this problem?

Thank you. So that's it, although I have some thoughts of my own which I could try to answer him, I don't know this aircraft well enough to provide a trustworthy answer. So may I hear it from the experts out there! Cheers

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I think I know the answer for question #1. If I were to guess, I'd say that unlike the 747, the 737 still has cables linking the flight controls to the ailerons and elevators. That's what allows for manual reversion in case of total hydraulic failure. Even without hydraulic pressure, the cables maintain the surfaces centered. Other modern airliners, like the 747, 777 and the Airbuses, have no physical linkage between the flight controls and those moving surfaces, so when hydraulic pressure drops there's nothing to keep them raised, thus they drop. I believe the rudder turns to one side because without HYD pressure the rudder acctuators lock and force the rudder in that direction. I'm guessing here, so I stand to be corrected. Regarding #2, I don't know how much more drag a 737NG produces compared to the A320, but I know Ryan have said that the NGs are very slippery airplanes, especially the -800WL, so if you don't plan you descent carefully, which includes entering wind information in the FORECAST page on the CDU, trying to maintain the descent as shallow as possible and so on, you'll surely have to deploy speedbrakes. I fly almost exclusively with the -800WL and to avoid going above the scheduled descent speeds I plan the descent as soon as possible and try to let the FMS know how the winds are across the descent, filling the FORECAST page with a wide range of wind data. Generally, I enter wind speeds for FL340, FL240 and FL120 and also the ISA temp deviation and QNH at the destination airport, as well as inputting speed contraints like 210 and 180 knots in the waypoints closer to the final approach course. That way the plane slows down appropriatelly for a smooth approach. If I do all this, I don't have to use speedbrakes at all at descent. I have no clue on #3, though.

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The rudder is the only flight control in the 737 that is fully hydraulic, all other can be moved (not too much in NGX) without hydraulic power.When pumps are turned OFF, NGX simulates also the pressure drop, so, the flight controls will be avaiable for seconds before losing them.Flaps and slats uses more power than a primary flight control (expecially if not hardly moved), and they will stop as soon as the pressure is removed (maybe just a second or 2)Without pressure, rudder will not move, winds can move it.NGX does not simulate the stby rudder system, except for the STBY RUD ON on the panel.

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Thanks for the reply all.

3. Is caused by ASX
As for this, do you know why ASX is causing such an issue? And whether there are any ways to have this fixed or overcame?

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I discovered this issue was occurring and noticed it was associated with wind shifts. Since other people had wind shifts without break failures, I tested it after disabling ASX's wind shift stabilization. This fixed the problem.Since flying with wind shifts and without windshifts stabilization is just about impossible, I switched to FSRealWX.

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