High angle-of-attack in Jetliners

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High angle-of-attack in Jetliners

Postby Kartoffelsalatatatat » Sun Mar 09, 2008 8:55 am

Hey

This is something I've always been wondering. Whenever I'm flying a jetliner I always seem to have a relatively high AoA at lower speeds. For instance, when flying @ 220KTS IAS, -1000 F/min descent I find myself with a 5 to 10o nose-up attitude. Flaps don't seem to correct this problem.

Anyone know whether this in supposed to happen, or I am such a terrible pilot? :D
Err. This is your captain speaking. There is absolutely no cause for alarm.

The wings are not on fire.
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Re: High angle-of-attack in Jetliners

Postby DaveSims » Sun Mar 09, 2008 4:40 pm

May just be the aircraft model you are using.  Typically a few notches of flap would get the nose down.
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Re: High angle-of-attack in Jetliners

Postby beaky » Sun Mar 09, 2008 8:36 pm

May just be the aircraft model you are using.  Typically a few notches of flap would get the nose down.

Read the OP... there's important info re: flaps.

The bottom line: FS9 is an approximation.
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Re: High angle-of-attack in Jetliners

Postby Kartoffelsalatatatat » Mon Mar 10, 2008 4:04 am

Ok, so I did some other experimenting with flap settings, and I found out it actually does make a difference, but I wasn't using enough flap. At around 15o flap setting, the AoA is about 2.5o. However, I still can't get the nose to go below the horizon, which one would expect from a descending airliner. The way I'm doing my approach now seems like one long flare.
Err. This is your captain speaking. There is absolutely no cause for alarm.

The wings are not on fire.
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Re: High angle-of-attack in Jetliners

Postby Brett_Henderson » Mon Mar 10, 2008 9:32 am

Hey

This is something I've always been wondering. Whenever I'm flying a jetliner I always seem to have a relatively high AoA at lower speeds. For instance, when flying @ 220KTS IAS, -1000 F/min descent I find myself with a 5 to 10o nose-up attitude. Flaps don't seem to correct this problem.

Anyone know whether this in supposed to happen, or I am such a terrible pilot? :D


I don't fly the tubes very often.. so I just took the default 737 up for a test. First, we have to differentiate between pitch angle and AoA.. they aren't interchangable, even if the wing's angle of incidence is zero. Assuming that the wing has no incidence (wing's pitch = fuselage pitch), a wing
Last edited by Brett_Henderson on Mon Mar 10, 2008 9:33 am, edited 1 time in total.
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Re: High angle-of-attack in Jetliners

Postby C » Wed Mar 12, 2008 11:01 am

Just come back from a trip where I was going to have a look. Sadly, as one normally does when it actually came to the approach, other things were on my mind! What I can tell you is that during the whole stage between 250kts and down the approach, the highest the nose ever went was 4 to 5 degrees above the horizon, just before the final approach, level with gear down and t/o (20*) flap. :)
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Re: High angle-of-attack in Jetliners

Postby Slotback » Thu Mar 13, 2008 11:56 pm

Atleast you're not in an MD-11. At MTOW Slats retract at 270kots or so.  :-?
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Re: High angle-of-attack in Jetliners

Postby C » Fri Mar 14, 2008 4:26 am

Atleast you're not in an MD-11. At MTOW Slats retract at 270kots or so.  :-?


At MTOW our slats are still coming in towards 250kts... ;)
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Re: High angle-of-attack in Jetliners

Postby Slotback » Fri Mar 14, 2008 9:42 am

[quote][quote]Atleast you're not in an MD-11. At MTOW Slats retract at 270kots or so.
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Re: High angle-of-attack in Jetliners

Postby C » Fri Mar 14, 2008 10:50 am

Atleast you're not in an MD-11. At MTOW Slats retract at 270kots or so.  :-?


At MTOW our slats are still coming in towards 250kts... ;)

DO you fly the MD-11?


Nope, and probably never will. :)
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