negative dihedral

Tina wrote in
:

On Jun 4, 12:03 pm, Bertie the Bunyip wrote:
Tina wrote
innews:57ee2ec3-c172-4f53-96a3-cec87ee7be22
@k37g2000hsf.googlegroups.c
om:

On Jun 4, 11:23 am, Bertie the Bunyip wrote:
Tina wrote
innews:4cc0ec37-d80c-4006-9190-





m:

On Jun 4, 4:49 am, HARRY POTTER wrote:
Tina wrote:
I understand how positive dihedral helps dynamic stability in
airplanes, but some big ones, like the Russian An 124 Condor,
has a pronounced negative dihedral -- the wings have a
noticeable downward slope.

Q1: Do those airplanes need active fly by wire controls to
maintain stability, or is something else at play that keeps
them right side up?

Q2: Does anyone have a design rationalization for such a
configuration, as opposed to just zero dihedral? I can
appreciate why fighters have it -- they exploit lack of
aerodynamic stability for rapid maneuvers -- but transports
that spend their whole life being straight and level are
another issue.

Note: I have not morphed into an Mx clone!

The AN124 does not have negative dihedral. It just looks that
way when it's on the ground because the weight of the engines
bends the wings so they look drooped down. Once it's in the
air, the fuselage bends the wings the other way, so it actually
does have dihedral.

--http://onlinelogbook.net

Thanks -- didn't realize it was simply wing droop when they are
not developing lift. That's what happens when you fly in stiff
winged little airplanes, you start overlooking something as
obvious as that.

http://www.youtube.com/watch?v=WJscAaKfr7A

Bertie

OK, I see some of the downslope was washed out in flight, but it
was still obvious there. Thanks

I expect more is washed out when the airplane is at gross weight,
but your point is made, Bertie.

Um, washout is probably not the best term, being share with another
important wing feature, but yeah, it's still there even when the
airplane is very heavy. I've seen the 225 fly and it's the same.
There'a also the little BAe 146 and the C5 and the C141 and the other
little bay antonov etc. I also mentioned I had seen some striaght
wing airplanes with anhedral but couldn't remember where. Most of the
turboprop antonovs have anhedral, but not nearly as much as the jets.
He obviously liked his airplanes to be manueverable!
Even a lot of the low wing jets had anhedral. The IL 62, for
instance.and IIRC some of the Tupovlevs also had it.

There was a country music guy who had a Mitsubishi twin with what I
remember looked liked pronounced anhedral, but I did a web search and
couldn't find a photo of it. What I am remembering might have been in
the 1970s.

There's little doubt in my mind that a high wing configuration with
negative dihedral would be more stable than a low winged one -- the cg
being way under the center of lift would see to that -- but still
don't have a 'model' to explain why wing sweep is a factor: when I
have some time I'll think about that, or I suppose I could ask
Anthony.

As for new stuff in aviation? I'd say GPS, released to the general
public during the RR presidency because of the Koran jet shootdown in
Russia, is fairly new. And let us not forget the new and improved FAA.

FAA hs nothing to do with aviation! And as for GPS, it's just a tidied
up and warmed up version of a lot of older distance measured based stuff
like decca and to a lesser extent, tacan, so it's not really new, just a
more advanced and more precise system with the stations placed in space
instead of higgildy-piggildy over the landscape. It's real hard to find
something new under the sun! i can't think of anything earlier than
Decca here, but I'm sure that even that's based on something that
Polynesian sailors or somebody were doing 4,000 years ago!

Bertie

I'm doing my part to add to the recreation in rec.aviation (and trying
to not have it be wreck.aviation).

On Jun 4, 12:30 pm, Bertie the Bunyip wrote:
Tina wrote :

On Jun 4, 12:03 pm, Bertie the Bunyip wrote:
Tina wrote
innews:57ee2ec3-c172-4f53-96a3-cec87ee7be22

@k37g2000hsf.googlegroups.c



om:

On Jun 4, 11:23 am, Bertie the Bunyip wrote:
Tina wrote
innews:4cc0ec37-d80c-4006-9190-



m:

On Jun 4, 4:49 am, HARRY POTTER wrote:
Tina wrote:
I understand how positive dihedral helps dynamic stability in
airplanes, but some big ones, like the Russian An 124 Condor,
has a pronounced negative dihedral -- the wings have a
noticeable downward slope.

Q1: Do those airplanes need active fly by wire controls to
maintain stability, or is something else at play that keeps
them right side up?

Q2: Does anyone have a design rationalization for such a
configuration, as opposed to just zero dihedral? I can
appreciate why fighters have it -- they exploit lack of
aerodynamic stability for rapid maneuvers -- but transports
that spend their whole life being straight and level are
another issue.

Note: I have not morphed into an Mx clone!

The AN124 does not have negative dihedral. It just looks that
way when it's on the ground because the weight of the engines
bends the wings so they look drooped down. Once it's in the
air, the fuselage bends the wings the other way, so it actually
does have dihedral.

--http://onlinelogbook.net

Thanks -- didn't realize it was simply wing droop when they are
not developing lift. That's what happens when you fly in stiff
winged little airplanes, you start overlooking something as
obvious as that.

http://www.youtube.com/watch?v=WJscAaKfr7A

Bertie

OK, I see some of the downslope was washed out in flight, but it
was still obvious there. Thanks

I expect more is washed out when the airplane is at gross weight,
but your point is made, Bertie.

Um, washout is probably not the best term, being share with another
important wing feature, but yeah, it's still there even when the
airplane is very heavy. I've seen the 225 fly and it's the same.
There'a also the little BAe 146 and the C5 and the C141 and the other
little bay antonov etc. I also mentioned I had seen some striaght
wing airplanes with anhedral but couldn't remember where. Most of the
turboprop antonovs have anhedral, but not nearly as much as the jets.
He obviously liked his airplanes to be manueverable!
Even a lot of the low wing jets had anhedral. The IL 62, for
instance.and IIRC some of the Tupovlevs also had it.

There was a country music guy who had a Mitsubishi twin with what I
remember looked liked pronounced anhedral, but I did a web search and
couldn't find a photo of it. What I am remembering might have been in
the 1970s.

There's little doubt in my mind that a high wing configuration with
negative dihedral would be more stable than a low winged one -- the cg
being way under the center of lift would see to that -- but still
don't have a 'model' to explain why wing sweep is a factor: when I
have some time I'll think about that, or I suppose I could ask
Anthony.

As for new stuff in aviation? I'd say GPS, released to the general
public during the RR presidency because of the Koran jet shootdown in
Russia, is fairly new. And let us not forget the new and improved FAA.

FAA hs nothing to do with aviation! And as for GPS, it's just a tidied
up and warmed up version of a lot of older distance measured based stuff
like decca and to a lesser extent, tacan, so it's not really new, just a
more advanced and more precise system with the stations placed in space
instead of higgildy-piggildy over the landscape. It's real hard to find
something new under the sun! i can't think of anything earlier than
Decca here, but I'm sure that even that's based on something that
Polynesian sailors or somebody were doing 4,000 years ago!

Bertie


I have a friend who works for an unnamed branch of the Federal
Government who said he could tell you what really is new in aviation,
but then he said he'd have to kill you,

then shred you,

and put what's left into a burn bag.

So the question before us is, should Bertie be briefed in?


This is how you can tell who your real friends are, Bertie.

Tina wrote in
:

On Jun 4, 12:30 pm, Bertie the Bunyip wrote:
Tina wrote
innews:db192ddb-52dd-4693-a681-b4f949b66053
@m3g2000hsc.googlegroups.co
m:

On Jun 4, 12:03 pm, Bertie the Bunyip wrote:
Tina wrote
innews:57ee2ec3-c172-4f53-96a3-cec87ee7be22

@k37g2000hsf.googlegroups.c



om:

On Jun 4, 11:23 am, Bertie the Bunyip wrote:
Tina wrote
innews:4cc0ec37-d80c-4006-9190-



m:

On Jun 4, 4:49 am, HARRY POTTER
wrote:
Tina wrote:
I understand how positive dihedral helps dynamic stability
in airplanes, but some big ones, like the Russian An 124
Condor, has a pronounced negative dihedral -- the wings
have a noticeable downward slope.

Q1: Do those airplanes need active fly by wire controls to
maintain stability, or is something else at play that
keeps them right side up?

Q2: Does anyone have a design rationalization for such a
configuration, as opposed to just zero dihedral? I can
appreciate why fighters have it -- they exploit lack of
aerodynamic stability for rapid maneuvers -- but
transports that spend their whole life being straight and
level are another issue.

Note: I have not morphed into an Mx clone!

The AN124 does not have negative dihedral. It just looks
that way when it's on the ground because the weight of the
engines bends the wings so they look drooped down. Once it's
in the air, the fuselage bends the wings the other way, so
it actually does have dihedral.

--http://onlinelogbook.net

Thanks -- didn't realize it was simply wing droop when they
are not developing lift. That's what happens when you fly in
stiff winged little airplanes, you start overlooking
something as obvious as that.

http://www.youtube.com/watch?v=WJscAaKfr7A

Bertie

OK, I see some of the downslope was washed out in flight, but it
was still obvious there. Thanks

I expect more is washed out when the airplane is at gross
weight, but your point is made, Bertie.

Um, washout is probably not the best term, being share with
another important wing feature, but yeah, it's still there even
when the airplane is very heavy. I've seen the 225 fly and it's
the same. There'a also the little BAe 146 and the C5 and the C141
and the other little bay antonov etc. I also mentioned I had seen
some striaght wing airplanes with anhedral but couldn't remember
where. Most of the turboprop antonovs have anhedral, but not
nearly as much as the jets. He obviously liked his airplanes to be
manueverable! Even a lot of the low wing jets had anhedral. The IL
62, for instance.and IIRC some of the Tupovlevs also had it.

There was a country music guy who had a Mitsubishi twin with what I
remember looked liked pronounced anhedral, but I did a web search
and couldn't find a photo of it. What I am remembering might have
been in the 1970s.

There's little doubt in my mind that a high wing configuration with
negative dihedral would be more stable than a low winged one -- the
cg being way under the center of lift would see to that -- but
still don't have a 'model' to explain why wing sweep is a factor:
when I have some time I'll think about that, or I suppose I could
ask Anthony.

As for new stuff in aviation? I'd say GPS, released to the general
public during the RR presidency because of the Koran jet shootdown
in Russia, is fairly new. And let us not forget the new and
improved FAA.

FAA hs nothing to do with aviation! And as for GPS, it's just a
tidied up and warmed up version of a lot of older distance measured
based stuff like decca and to a lesser extent, tacan, so it's not
really new, just a more advanced and more precise system with the
stations placed in space instead of higgildy-piggildy over the
landscape. It's real hard to find something new under the sun! i
can't think of anything earlier than Decca here, but I'm sure that
even that's based on something that Polynesian sailors or somebody
were doing 4,000 years ago!

Bertie


I have a friend who works for an unnamed branch of the Federal
Government who said he could tell you what really is new in aviation,
but then he said he'd have to kill you,

then shred you,

and put what's left into a burn bag.

So the question before us is, should Bertie be briefed in?


This is how you can tell who your real friends are, Bertie.




Heh heh. I'm insatiably curious so I'm tempted! But unless he's talking
about antigravity, you could probably trace some bit of whatever bit of
airplane he's talking about back to some point way back. In fact, even
if he were talking about antigravity, it's probably got soem of it's
roots in something the Nazis were playing with in Prague or one of
Tesla's half mad notions...


Bertie

On Jun 4, 2:15 pm, Bertie the Bunyip wrote:
Tina wrote :

On Jun 4, 12:30 pm, Bertie the Bunyip wrote:
Tina wrote
innews:db192ddb-52dd-4693-a681-b4f949b66053

@m3g2000hsc.googlegroups.co



m:

On Jun 4, 12:03 pm, Bertie the Bunyip wrote:
Tina wrote
innews:57ee2ec3-c172-4f53-96a3-cec87ee7be22

@k37g2000hsf.googlegroups.c

om:

On Jun 4, 11:23 am, Bertie the Bunyip wrote:
Tina wrote
innews:4cc0ec37-d80c-4006-9190-



m:

On Jun 4, 4:49 am, HARRY POTTER
wrote:
Tina wrote:
I understand how positive dihedral helps dynamic stability
in airplanes, but some big ones, like the Russian An 124
Condor, has a pronounced negative dihedral -- the wings
have a noticeable downward slope.

Q1: Do those airplanes need active fly by wire controls to
maintain stability, or is something else at play that
keeps them right side up?

Q2: Does anyone have a design rationalization for such a
configuration, as opposed to just zero dihedral? I can
appreciate why fighters have it -- they exploit lack of
aerodynamic stability for rapid maneuvers -- but
transports that spend their whole life being straight and
level are another issue.

Note: I have not morphed into an Mx clone!

The AN124 does not have negative dihedral. It just looks
that way when it's on the ground because the weight of the
engines bends the wings so they look drooped down. Once it's
in the air, the fuselage bends the wings the other way, so
it actually does have dihedral.

--http://onlinelogbook.net

Thanks -- didn't realize it was simply wing droop when they
are not developing lift. That's what happens when you fly in
stiff winged little airplanes, you start overlooking
something as obvious as that.

http://www.youtube.com/watch?v=WJscAaKfr7A

Bertie

OK, I see some of the downslope was washed out in flight, but it
was still obvious there. Thanks

I expect more is washed out when the airplane is at gross
weight, but your point is made, Bertie.

Um, washout is probably not the best term, being share with
another important wing feature, but yeah, it's still there even
when the airplane is very heavy. I've seen the 225 fly and it's
the same. There'a also the little BAe 146 and the C5 and the C141
and the other little bay antonov etc. I also mentioned I had seen
some striaght wing airplanes with anhedral but couldn't remember
where. Most of the turboprop antonovs have anhedral, but not
nearly as much as the jets. He obviously liked his airplanes to be
manueverable! Even a lot of the low wing jets had anhedral. The IL
62, for instance.and IIRC some of the Tupovlevs also had it.

There was a country music guy who had a Mitsubishi twin with what I
remember looked liked pronounced anhedral, but I did a web search
and couldn't find a photo of it. What I am remembering might have
been in the 1970s.

There's little doubt in my mind that a high wing configuration with
negative dihedral would be more stable than a low winged one -- the
cg being way under the center of lift would see to that -- but
still don't have a 'model' to explain why wing sweep is a factor:
when I have some time I'll think about that, or I suppose I could
ask Anthony.

As for new stuff in aviation? I'd say GPS, released to the general
public during the RR presidency because of the Koran jet shootdown
in Russia, is fairly new. And let us not forget the new and
improved FAA.

FAA hs nothing to do with aviation! And as for GPS, it's just a
tidied up and warmed up version of a lot of older distance measured
based stuff like decca and to a lesser extent, tacan, so it's not
really new, just a more advanced and more precise system with the
stations placed in space instead of higgildy-piggildy over the
landscape. It's real hard to find something new under the sun! i
can't think of anything earlier than Decca here, but I'm sure that
even that's based on something that Polynesian sailors or somebody
were doing 4,000 years ago!

Bertie

I have a friend who works for an unnamed branch of the Federal
Government who said he could tell you what really is new in aviation,
but then he said he'd have to kill you,

then shred you,

and put what's left into a burn bag.

So the question before us is, should Bertie be briefed in?

This is how you can tell who your real friends are, Bertie.

Heh heh. I'm insatiably curious so I'm tempted! But unless he's talking
about antigravity, you could probably trace some bit of whatever bit of
airplane he's talking about back to some point way back. In fact, even
if he were talking about antigravity, it's probably got soem of it's
roots in something the Nazis were playing with in Prague or one of
Tesla's half mad notions...

Bertie

In cases like these the argument "I knew that anyhow"when standing on
the threshold of the shredder don't hold a lot of water.

Actually what we are seeing academically is the need for face to face
meetings is beginning to diminish. We worry in the shrink world about
standardized observations in clinical trials, and are getting good
results with teleconferencing instead of having our 'standardized'
observer go to different sites to view subjects. The new thing might
very well be a reduction in business related air travel.

That is also becoming a reality in hi tech business. We are seeing
teleconferencing as effective as meeting face to face, at a great
saving of time and money. Teleconferencing will not, however, replace
the annual two week trip across the country with customers located
about 500 miles apart -- so easy to do by sel, and so difficult most
other ways. We do need to find a potential customer to visit in
Jackson Hole, Las Vegas, and near Lake Tahoe. (You do your business
planning your way, we'll do ours our way).

"Tina" wrote in message
...
There was a country music guy who had a Mitsubishi twin with what I
remember looked liked pronounced anhedral, but I did a web search and
couldn't find a photo of it. What I am remembering might have been in
the 1970s.

Mitsubishi MU2, from the nice folks who brought us the Zero. This phote shows
the apparent anhedral: http://tinyurl.com/5rhlka

Vaughn

Bertie the Bunyip wrote:



http://www.youtube.com/watch?v=WJscAaKfr7A



Ooops, that was a MSFS one. ----------
/snip/

Am I the only one who sees the *immense* irony in this?

Happy Flying!
Scott Skylane

Scott Skylane wrote in news:Z5-
ommunications:

Bertie the Bunyip wrote:



http://www.youtube.com/watch?v=WJscAaKfr7A



Ooops, that was a MSFS one. ----------
/snip/

Am I the only one who sees the *immense* irony in this?

Nope.

Bertie

"Bertie the Bunyip" wrote in message
...

Actually, that's not the case in every sense. They're not very speed
stable, for instance and thye have other problems with two diferent
kinds of dutch roll, related to sweep, mostly.

Bertie

Keep guessing wannabe, got a link?

"Maxwell" luv2^fly99@cox.^net wrote in news:9aF1k.1876$nD3.800
@newsfe15.lga:


"Bertie the Bunyip" wrote in message
...

Actually, that's not the case in every sense. They're not very speed
stable, for instance and thye have other problems with two diferent
kinds of dutch roll, related to sweep, mostly.

Bertie

Keep guessing wannabe, got a link?




Nope. Don't need one.



Bertie

"Bertie the Bunyip" wrote in message
...

Yes, if you had a striaght wing airplane like that it would tend to do
it left to its; own devices, but a swept wing airplane well tend to
resist yaw, and by association, roll by virtue of the sweep alone.



Bertie

Sure it does Bertie Buttlipp, you know everything, you know everyone, you've
done everything. Gotta link?