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XyZspineZyX
07-09-2003, 08:47 PM
Is there some way to control the slats inclination degrees in the 109? And if it does, how does it affect the performance??

XyZspineZyX
07-09-2003, 08:47 PM
Is there some way to control the slats inclination degrees in the 109? And if it does, how does it affect the performance??

XyZspineZyX
07-09-2003, 09:42 PM
The slats are "automatically" deployed by aerodynamics. What that means is, the slats are free to slide in and out by themselves. They are not actuated by any kind of mechanical device. When the wing reaches a certain angle of attack, they begin to come out. At lower angles of attack, air pressure on the leading edge of the slats keep them in place.

XyZspineZyX
07-09-2003, 09:57 PM
And they don´t plop out!! /i/smilies/16x16_smiley-wink.gif there is no spring or something.. it´s the pure airstream, suck them out or push´em in! /i/smilies/16x16_smiley-wink.gif

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XyZspineZyX
07-10-2003, 12:35 AM
be nice effect to hear the slats bang open and closed

XyZspineZyX
07-10-2003, 01:32 AM
Oooohhh, I see
Now that explains that advice on the 109 performance:"Tend to spin if the slats inclination is unequal" or something like that /i/smilies/16x16_smiley-happy.gif

XyZspineZyX
07-10-2003, 01:41 AM
Abbuzze wrote:
- And they don´t plop out!! /i/smilies/16x16_smiley-wink.gif there is no spring or
- something.. it´s the pure airstream, suck them out
- or push´em in! /i/smilies/16x16_smiley-wink.gif
-
- JG53 PikAs Abbuzze
- I./Gruppe
-
- http://www.jg53-pikas.de/
<img
- src="http://mitglied.lycos.de/p123/Ani_pikasbanner
- _langsam.gif">
-
-


I'm not sure that's strictly true (being sucked out) as when sitting on the ground on during takeoff they are most certainly plopping out. It appears that pressure of the airstream against the leading edge that keeps them against the wing. When going too slow or the airsteam angle is tilted enough they come out!

XyZspineZyX
07-10-2003, 01:44 AM
so let me get this straight: If you are in a level flight, they keep almost closed, but if u are making a maneuver(say a loop) It will bust open? The slats could break off in a steep dive like the rest of the plane? I dunno if they were gonna blast off first or last though

XyZspineZyX
07-10-2003, 01:55 AM
Apparently with enough angle of attack or slow enough airspeed they deploy. They were known to deploy when performing at the top of a loop for example.

XyZspineZyX
07-10-2003, 04:04 AM
they were also known to deploy asymetrically .. one open and one closed .. this was not regarded as a good thing

XyZspineZyX
07-10-2003, 04:17 AM
Do a google for Handley Page slats, lots of info on their operation and history.

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XyZspineZyX
07-10-2003, 04:58 AM
Automated slats still exist in smaller aircrafts, and help aircrafts in gaining a higher angle of attack AOA, which helps the wing from stalling at, for example, low speed, while on final for landing. The Bf-109 had a very thin laminar profile that didn't really favour low speed/high AOA, and the slat was the cost-efficient solution.

XyZspineZyX
07-10-2003, 08:11 AM
jmmoric wrote:
- Automated slats still exist in smaller aircrafts,


Well .. the cessna citation has slats http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

you cannot get too much more current than a Citation http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif


http://www.planegallery.net/planes/images/citx2.jpg

XyZspineZyX
07-10-2003, 08:15 AM
F1NaZZ1 wrote:
- Oooohhh, I see
- Now that explains that advice on the 109
- performance:"Tend to spin if the slats inclination
- is unequal" or something like that /i/smilies/16x16_smiley-happy.gif
-
-

I think that was only a problem with E-series where the aileron extended to the tip of the wing.


-jippo

XyZspineZyX
07-10-2003, 08:43 AM
WTE_Galway wrote:
- be nice effect to hear the slats bang open and
- closed

I've read it many times that they could be heard banging open and shut. I find it hard to understamd, though. I fly reasonably often one of those dinky little planes that do have slats, that bang open/shut if flown without flaps (they open/shut less violently with flaps down.) I've never once heard any sound when they do, and this is with a puny 180HP Lycoming engine in the front. When they bang open/shut, you can feel a rather sharp shudder in the plane, though. Can that be what they mean?
_
/Bjorn.

XyZspineZyX
07-10-2003, 08:55 AM
To answer a few questions...

You see many pictures with open slats at the ground cause the planes where slow while landing, but as I know you can "press" them in the wing with one finger, there are also pictures with slats in at the ground.

The asymetical function - most pilots complaining about this where allie testpilots, cause they weren´t used to this funktion.
It´s understandable, if you are not used to this it´s real frightend, but on the other side it´s a big advantage, for example in a real tight 80-90? Combat turn, ALL planes have the tendency to loose lift 1st at the "lower" wing, if you go to far you have a stall at this wing and your plane will flip over. In this moment the asymetrical funtion of the slat start.. the lower wing slat come out brings more lift at this wing and avoid this flip over, if both would open symetrical you can perhaps turn a bit tighter, but you will have this tendency to flip over like all other planes without slats.

So this slats are making it easier to go to the edge. In BoB some Emil Pilots reportet that they where able to follow Spits in the 1st time of a thight turn cause some Spitpilots didn´t pull hard enough cause they didn´t want to stall immediatelly, in the 109 you can pull hard till the slats coming out, then you have to be carefull. They used them as a kind of indicator.

Also read from a pilot that this fact make it more easy to fly drunk! /i/smilies/16x16_smiley-wink.gif

Edit: I forgot, yes in the slipstream of a big 4 engine bomber the slats are causing troubles....

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Message Edited on 07/10/0312:01PM by Abbuzze

XyZspineZyX
07-10-2003, 12:59 PM
WTE_Galway wrote:
- they were also known to deploy asymetrically .. one
- open and one closed .. this was not regarded as a
- good thing

Wrong. It WAS a good thing. Less spin %age for sure.



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