H-Stab Anahedral
H-Stab Anahedral
The HS is simply an inverted wing because it needs to impart a downward moment in order to keep the nose up. So what you're looking at is an upside down wing nothing to do with stability as far as I know I'm sure someone will come through with a more detailed answer to your query but I hope this helps
The HS is simply an inverted wing because it needs to impart a downward moment in order to keep the nose up.
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From somewhere in the depths of fluid dynamics courses of fifty years ago, I have retained an impression that use of di/an-hedral was connected with roll stability. So what are the benefits of having the tail less stable in roll than the wing?
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Discussed in 2005 here.
I was told they accidently put them on upside down on the prototype and it worked so well, they kept them...
While on the subject of anhedral, can anyone put me out of my misery regarding why all of the Russian rear engined airliners have a pronounced anhedral on the wings.
Last edited by Hobo; 28th Oct 2013 at 16:23.
On the ground, with the surface trimmed neutral, any ice that is melting in the sun might just sit there until it has a chance to refreeze. Add anhedral and voila! Ice gone.
(No I don't design aircraft - you're all safe
(No I don't design aircraft - you're all safe
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As I said, it could be several reasons.
Zeffy's photo is, I think, a Falcon, so let's take that.
Tail anhedral will reduce the aircraft rolling moment due to sideslip, which will change the balance between dutch roll and spiral stability a little bit. But unless someone can say that the Falcon is "iffy" in either of those quantities that is unlikely to be the reason.
In his book "JAR Professional Pilot Studies" Phil Croucher writes:
Hope that helps
Zeffy's photo is, I think, a Falcon, so let's take that.
Tail anhedral will reduce the aircraft rolling moment due to sideslip, which will change the balance between dutch roll and spiral stability a little bit. But unless someone can say that the Falcon is "iffy" in either of those quantities that is unlikely to be the reason.
In his book "JAR Professional Pilot Studies" Phil Croucher writes:
Anhedral reduces the lateral stability. In the Falcon, where it is used on the tailplane, it improves flying qualities by reducing the effect of wing downwash
Per Ardua ad Astraeus
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F-4 stab anhedral was for aesthetic reasons
aesthetic - concerned with beauty or the appreciation of beauty.
I almost choked on a peanut there..............................
aesthetic - concerned with beauty or the appreciation of beauty.
I almost choked on a peanut there..............................
F-4 stab anhedral was for aesthetic reasons.
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F-4 stab anhedral was for aesthetic reasons.
From an FT course years ago, I recall a discussion which suggested that the original design called for a T-tail .. subsequently changed as that configuration wouldn't have made the cut for carrier operations.
From an FT course years ago, I recall a discussion which suggested that the original design called for a T-tail .. subsequently changed as that configuration wouldn't have made the cut for carrier operations.
I recall a discussion which suggested that the original design called for a T-tail
subsequently changed as that configuration wouldn't have made the cut for carrier operations.