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FMC and bank angle limit?

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I notice when i'm using the AP in HDG mode it seems to obey the bank angle limit. However in LNAV with the FMCwe always turn at a very steep angle.Feel free to flame if i'm doing something silly here! Pete

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>I notice when i'm using the AP in HDG mode it seems to >obey the bank angle limit. However in LNAV with the FMC>we always turn at a very steep angle.>>Feel free to flame if i'm doing something silly here! >>Pete Hello Pete, Well not too funny ;-) but truth be told the AFDS controls the bank in A/P and one cannot change it. The BL works only in HDG mode....[h4]Randy J. Smith[/h4]

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Is that the same in the real aircraft?Hopefully not as it would be very alarming if the FMC could take the aircraft into a 30 degree bank while the hosties are serving a bite to eat :D Pete

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>Is that the same in the real aircraft?>Yes, it is the same, the autoflight can command up to a 30 degree bank angle in LNAV. The actual angle will be what's needed to maintain the calculated track through the turn. There's probably some target bank angle, I don't know what that is though. It's independent of the bank angle limiter just like in the PMDG aircraft.

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30 Degree Bank isn't that intense really. At that altitude and at that speed, 30 degrees isn't intense what so ever. I doubt you would even notice it unless you were looking at the wings.

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From a real 767 pilot:"The autopilot smoothly flies the turn and we have set our course toward 4540N. When in the navigational mode, the angle of bank used by the autopilot is a function of speed and altitude, and up here, near the performance ceiling, you don't want a large bank angle. The wing loses a bit of lift in a bank, or, rather, the lift vector changes from straight up to off-vertical. Since only the vertical component of lift tends to keep us at altitude, the horizontal component created by the bank angle is no longer of use to us, except to pull the airplane through the turn. The Flight Control Computers take all of this into account, and bank angles above around 20,000 feet are reduced. Up here, the FCC's are using less than five degrees of bank to make this 14-degree heading change. No whitecaps in the martinis in the back!"http://www.flightsim.com/cgi/kds?$=main/feature/argosy1.htm

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