Slats and Fowler Flaps On Light Plane

[Brock]

I feel there is a real advantage to the use of slats and flaps in
order to have things happen slowly during landing and yet still have a
good cruise speed. Of course the problem is in the complexity and the
extra weight. For rails I was thinking about something like standard
kitchen drawer rails or perhaps a tube within a tube design. I
wouldn't think their would be a lot of force on the slat at low
takeoff speeds so the structure wouldn't have to be bullet proof,
their would probably be a lot more force on the flaps though. I
haven't been able to find information if the necessary airplane
hardware is available commercially, perhaps it would have to be custom
made. Any ideas on how to go about building something like this?

Brock

[Barnyard BOb --]

On 25 Jul 2003 06:51:08 -0700, (Brock) wrote:

>I feel there is a real advantage to the use of slats and flaps in
>order to have things happen slowly during landing and yet still have a
>good cruise speed. Of course the problem is in the complexity and the
>extra weight. For rails I was thinking about something like standard
>kitchen drawer rails or perhaps a tube within a tube design. I
>wouldn't think their would be a lot of force on the slat at low
>takeoff speeds so the structure wouldn't have to be bullet proof,
>their would probably be a lot more force on the flaps though. I
>haven't been able to find information if the necessary airplane
>hardware is available commercially, perhaps it would have to be custom
>made. Any ideas on how to go about building something like this?
>
>Brock
+++++++++++++++++++++++++++++++++++++++

My FEELING is....
You can't safely get there from here.

Given the nature and level of your question....
perhaps you should look at aircraft designs
that you could copy or adapt to whatever
you have in mind.

Other than that, a degree in aero engineering might helpful
to bring you back to reality before someone is harmed.


Barnyard BOb -- stranger than fiction

[Kyle Boatright]

"Brock" > wrote in message
om...
> I feel there is a real advantage to the use of slats and flaps in
> order to have things happen slowly during landing and yet still have a
> good cruise speed. Of course the problem is in the complexity and the
> extra weight. For rails I was thinking about something like standard
> kitchen drawer rails or perhaps a tube within a tube design. I
> wouldn't think their would be a lot of force on the slat at low
> takeoff speeds so the structure wouldn't have to be bullet proof,
> their would probably be a lot more force on the flaps though. I
> haven't been able to find information if the necessary airplane
> hardware is available commercially, perhaps it would have to be custom
> made. Any ideas on how to go about building something like this?
>
> Brock

You could copy the flap design from the RV-10 or the Glasair series. Good
luck on the slats - those have to be built to very tight tolerances so they
operate at the same time. Differential slat extension has killed quite a few
people. Also, more than a few people have been killed by having a slat
depart the airframe in flight.

Vortex generators might be a safer alternative.

KB

[Bob Kuykendall]

Earlier, (Brock) wrote:

> For rails I was thinking about
> something like standard kitchen
> drawer rails or perhaps a tube
> within a tube design. I wouldn't
> think their would be a lot of
> force on the slat...

The two factors that might surprise you are the worst-case loads on an
extended slat at design limit loading, and the consequences of failure
of the actuators or the support rails. Taken together, they suggest
that the structure should be about as bulletproof as any other element
of primary structure.

> ...perhaps it would have to be
> custom made.

Almost certainly the case. Fortunately, the raw materials (bearings,
steel, aluminum) are all relatively cheap and plentiful. Let the
Aircraft Spruce (or Wicks) catalog be your guide and playground.

> Any ideas on how to go about
> building something like this?

Make a sectional model out of garbage (plywood, masonite, nails) and
keep modifying it until it gives good motion.

Then make a prototype of one of the actuator/support stations, and
load test it to validate that it supports loadings about 1.5x of the
maximum expected.

Then make a full-scale prototype and test it on the experimental
aircraft of your choice. Good luck.

The slats on the Me-109 (or Bf-109) might be a god model to start
from. I understand that they're just spring-loaded so they pop out
when the pressure at the stagnation point goes below a certain value.

Thanks, and best regards to all

Bob K.
http://www.hpaircraft.com/hp-24

[Philippe Vessaire]

Le Vendredi 25 Juillet 2003 18:50
Kyle Boatright a écrit:



> You could copy the flap design from the RV-10 or the Glasair series.
> Good luck on the slats - those have to be built to very tight
> tolerances so they operate at the same time. Differential slat
> extension has killed quite a few
> people. Also, more than a few people have been killed by having a
> slat depart the airframe in flight.

The slat MUST be built with mecanical link to operate together. See
what you can read about french design Morane Rallye ('60 to '80).
This plane had all the features you want.

By
--
Philippe Vessaire Ò¿Ó¬

[Ernest Christley]

Brock wrote:
> kitchen drawer rails or perhaps a tube within a tube design. I
> wouldn't think their would be a lot of force on the slat at low
> takeoff speeds so the structure wouldn't have to be bullet proof,

If there isn't a lot of force on them then they aren't doing you any good.


--
----Because I can----
http://www.ernest.isa-geek.org/
------------------------

[Peter Dohm]

Brock wrote:
>
> I feel there is a real advantage to the use of slats and flaps in
> order to have things happen slowly during landing and yet still have a
> good cruise speed. Of course the problem is in the complexity and the
> extra weight. For rails I was thinking about something like standard
> kitchen drawer rails or perhaps a tube within a tube design. I
> wouldn't think their would be a lot of force on the slat at low
> takeoff speeds so the structure wouldn't have to be bullet proof,
> their would probably be a lot more force on the flaps though. I
> haven't been able to find information if the necessary airplane
> hardware is available commercially, perhaps it would have to be custom
> made. Any ideas on how to go about building something like this?
>
> Brock

Whereas the Helio Courier and Morane Rallye (among others), and their
slats, are discussed elsewhere in the thread; I'll just mention that all
of the high wing Cessna aircraft with which I am familiar have single
slotted Fowler flaps. I have no idea how much performance you would
gain with double slotted Fowler flaps, and doubt that they would add
much weight; but believe that they would be a real pain in the neck to
build s the dimensions would need to be held closely in order for the
slots to have the correct proportions and the additional surfaces would
need to be finished.

Peter

[Big John]

Flew em both. Worked fine.

Big John

On Fri, 25 Jul 2003 18:56:13 GMT, "Capt. Doug"
> wrote:

>>Philippe Vessaire wrote in message > The slat MUST be built with mecanical
>link to >operate together. See
>> what you can read about french design Morane Rallye ('60 to '80).
>> This plane had all the features you want.
>
>For the proper way to design slats, study the Sabreliner and the
>Helio-Courier, neither of which is mechanically interconnected, or French.
>
>D. (couldn't resist)
>

[clare @ snyder.on .ca]

On Fri, 25 Jul 2003 23:27:14 GMT, Richard Lamb >
wrote:

>WHAT actuators, Bob.
>
>Most slats are deployed by aerodynamic forces,
>not mechanical ones...
>

The Pegazair has automatic, independent slats. Because they are
controlled by lift, or lack thereof, they only come out when needed,
and sometimes they are only needed on one side.
It is a Dedalius (spelling?) style wing - also supplied as an add-on
to the CH701, and, I believe, other planes. No springs either.


>Bob Kuykendall wrote:
>>
>> Earlier, (Brock) wrote:
>>
>> > For rails I was thinking about
>> > something like standard kitchen
>> > drawer rails or perhaps a tube
>> > within a tube design. I wouldn't
>> > think their would be a lot of
>> > force on the slat...
>>
>> The two factors that might surprise you are the worst-case loads on an
>> extended slat at design limit loading, and the consequences of failure
>> of the actuators or the support rails. Taken together, they suggest
>> that the structure should be about as bulletproof as any other element
>> of primary structure.
>>
>> > ...perhaps it would have to be
>> > custom made.
>>
>> Almost certainly the case. Fortunately, the raw materials (bearings,
>> steel, aluminum) are all relatively cheap and plentiful. Let the
>> Aircraft Spruce (or Wicks) catalog be your guide and playground.
>>
>> > Any ideas on how to go about
>> > building something like this?
>>
>> Make a sectional model out of garbage (plywood, masonite, nails) and
>> keep modifying it until it gives good motion.
>>
>> Then make a prototype of one of the actuator/support stations, and
>> load test it to validate that it supports loadings about 1.5x of the
>> maximum expected.
>>
>> Then make a full-scale prototype and test it on the experimental
>> aircraft of your choice. Good luck.
>>
>> The slats on the Me-109 (or Bf-109) might be a god model to start
>> from. I understand that they're just spring-loaded so they pop out
>> when the pressure at the stagnation point goes below a certain value.
>>
>> Thanks, and best regards to all
>>
>> Bob K.
>> http://www.hpaircraft.com/hp-24

[Richard Lamb]

Ernest Christley wrote:
>
> Brock wrote:
> > kitchen drawer rails or perhaps a tube within a tube design. I
> > wouldn't think their would be a lot of force on the slat at low
> > takeoff speeds so the structure wouldn't have to be bullet proof,
>
> If there isn't a lot of force on them then they aren't doing you any good.
>
> --
> ----Because I can----
> http://www.ernest.isa-geek.org/
> ------------------------

When the slats pop out on the Helio Courier based here,
it sounds like a shotgun. Loud BOOM!

There is indeed a lot of force here...

[Richard Lamb]

Steve Wittman had leading edge FLAPS (not slats) on his Buttercup.
Buttercup is a predecessor to the Wittman Tailwind.
That was back in the early '50s?

Anyway, the idea is to have a thin wing for high speed cruise and
recontour it into an undercambered thin wing to slow down for landing.

Thin airfoils tend to have low CLmax while recurred thin airfoils
can have amazingly high CLmax.

Taken to an extreme, the "sail" type single surfaced ultralight wings
show a CLmax of over 4(!)

Leading edge flaps are always(?) deployed in conjunction with trailing
edge flaps of some kind. Even if it is a simple split flap.

Otherwise, the CP would move way forward, and the chord line suddenly
goes the wrong way.

Earl Luce built the first replica Buttercup (and sells plans fo it too).

Earl said Buttercup lands in the low 40s with the flaps down.
Or over 70 (with a lot of skipping and skating) without them.

I did a little browsing at the NACA server and found a lot of info on
leading edge flaps. But it all seemed more applicable to supersonic and
high subsonic heavies.

To date, Buttercup is the only light plane I know of that has leading
edge flaps.

Richard


Peter Dohm wrote:
>
> Brock wrote:
> >
> > I feel there is a real advantage to the use of slats and flaps in
> > order to have things happen slowly during landing and yet still have a
> > good cruise speed. Of course the problem is in the complexity and the
> > extra weight. For rails I was thinking about something like standard
> > kitchen drawer rails or perhaps a tube within a tube design. I
> > wouldn't think their would be a lot of force on the slat at low
> > takeoff speeds so the structure wouldn't have to be bullet proof,
> > their would probably be a lot more force on the flaps though. I
> > haven't been able to find information if the necessary airplane
> > hardware is available commercially, perhaps it would have to be custom
> > made. Any ideas on how to go about building something like this?
> >
> > Brock
>
> Whereas the Helio Courier and Morane Rallye (among others), and their
> slats, are discussed elsewhere in the thread; I'll just mention that all
> of the high wing Cessna aircraft with which I am familiar have single
> slotted Fowler flaps. I have no idea how much performance you would
> gain with double slotted Fowler flaps, and doubt that they would add
> much weight; but believe that they would be a real pain in the neck to
> build s the dimensions would need to be held closely in order for the
> slots to have the correct proportions and the additional surfaces would
> need to be finished.
>
> Peter

[Peter Dohm]

Many excellent points.

I started to write that I don't know of anything written regarding
leading edge flaps, either. Then decided to try a search on
http://www.dogpile.com/ and I found a reference when I tried flap
(singular) as part of the search argument in leading+edge+flap and got
"Aerodynamic loads on a leading-edge flap and a leading-edge slat on
the NACA 64A101 airfoil section" John A Kelly & George B McCullough
http://naca.larc.gov/reports/1954/naca-tn-3220/naca-tn-3220.pdf

Unfortunately, I think you may need to know more about aerodynamics,
and some other things, to design anything really useful from it.
However, it appears intended to compare the characteristics of flaps
vs slats in in great detail; including graphs, sketched, and
tabulations of pressure distribution. And you and print it out.

Peter

By the way, the old Dover Edition of "Theory of Wing Sections" is
still available from various sources, and includes material on both
fixed and moveable slats alone and in combination with trailing
edge flaps. I don't recall whether leading edge flaps are also
discussed, and my copy seems to have hidden behind another book :-(

Richard Lamb wrote:
>
> Steve Wittman had leading edge FLAPS (not slats) on his Buttercup.
> Buttercup is a predecessor to the Wittman Tailwind.
> That was back in the early '50s?
>
> Anyway, the idea is to have a thin wing for high speed cruise and
> recontour it into an undercambered thin wing to slow down for landing.
>
> Thin airfoils tend to have low CLmax while recurred thin airfoils
> can have amazingly high CLmax.
>
> Taken to an extreme, the "sail" type single surfaced ultralight wings
> show a CLmax of over 4(!)
>
> Leading edge flaps are always(?) deployed in conjunction with trailing
> edge flaps of some kind. Even if it is a simple split flap.
>
> Otherwise, the CP would move way forward, and the chord line suddenly
> goes the wrong way.
>
> Earl Luce built the first replica Buttercup (and sells plans fo it too).
>
> Earl said Buttercup lands in the low 40s with the flaps down.
> Or over 70 (with a lot of skipping and skating) without them.
>
> I did a little browsing at the NACA server and found a lot of info on
> leading edge flaps. But it all seemed more applicable to supersonic and
> high subsonic heavies.
>
> To date, Buttercup is the only light plane I know of that has leading
> edge flaps.
>
> Richard
>
> Peter Dohm wrote:
> >
> > Brock wrote:
> > >
> > > I feel there is a real advantage to the use of slats and flaps in
> > > order to have things happen slowly during landing and yet still have a
> > > good cruise speed. Of course the problem is in the complexity and the
> > > extra weight. For rails I was thinking about something like standard
> > > kitchen drawer rails or perhaps a tube within a tube design. I
> > > wouldn't think their would be a lot of force on the slat at low
> > > takeoff speeds so the structure wouldn't have to be bullet proof,
> > > their would probably be a lot more force on the flaps though. I
> > > haven't been able to find information if the necessary airplane
> > > hardware is available commercially, perhaps it would have to be custom
> > > made. Any ideas on how to go about building something like this?
> > >
> > > Brock
> >
> > Whereas the Helio Courier and Morane Rallye (among others), and their
> > slats, are discussed elsewhere in the thread; I'll just mention that all
> > of the high wing Cessna aircraft with which I am familiar have single
> > slotted Fowler flaps. I have no idea how much performance you would
> > gain with double slotted Fowler flaps, and doubt that they would add
> > much weight; but believe that they would be a real pain in the neck to
> > build s the dimensions would need to be held closely in order for the
> > slots to have the correct proportions and the additional surfaces would
> > need to be finished.
> >
> > Peter

[Peter Dohm]

Oooops! I left NASA out of that URL and then forgot to test the
link in the message before I pressed send. The corrected version is:
"Aerodynamic loads on a leading-edge flap and a leading-edge slat on
the NACA 64A101 airfoil section" John A Kelly & George B McCullough
http://naca.larc.nasa.gov/reports/1954/naca-tn-3220/naca-tn-3220.pdf

Sorry about that.

Peter

[Big John]

The F-104 had both leading and trailing edge flaps and wing was
'blown'.

Big John
Mach 1+


On Sat, 26 Jul 2003 02:51:21 GMT, Richard Lamb >
wrote:

>Steve Wittman had leading edge FLAPS (not slats) on his Buttercup.
>Buttercup is a predecessor to the Wittman Tailwind.
>That was back in the early '50s?
>
>Anyway, the idea is to have a thin wing for high speed cruise and
>recontour it into an undercambered thin wing to slow down for landing.
>
>Thin airfoils tend to have low CLmax while recurred thin airfoils
>can have amazingly high CLmax.
>
>Taken to an extreme, the "sail" type single surfaced ultralight wings
>show a CLmax of over 4(!)
>
>Leading edge flaps are always(?) deployed in conjunction with trailing
>edge flaps of some kind. Even if it is a simple split flap.
>
>Otherwise, the CP would move way forward, and the chord line suddenly
>goes the wrong way.
>
>Earl Luce built the first replica Buttercup (and sells plans fo it too).
>
>Earl said Buttercup lands in the low 40s with the flaps down.
>Or over 70 (with a lot of skipping and skating) without them.
>
>I did a little browsing at the NACA server and found a lot of info on
>leading edge flaps. But it all seemed more applicable to supersonic and
>high subsonic heavies.
>
>To date, Buttercup is the only light plane I know of that has leading
>edge flaps.
>
>Richard
>
>
>Peter Dohm wrote:
>>
>> Brock wrote:
>> >
>> > I feel there is a real advantage to the use of slats and flaps in
>> > order to have things happen slowly during landing and yet still have a
>> > good cruise speed. Of course the problem is in the complexity and the
>> > extra weight. For rails I was thinking about something like standard
>> > kitchen drawer rails or perhaps a tube within a tube design. I
>> > wouldn't think their would be a lot of force on the slat at low
>> > takeoff speeds so the structure wouldn't have to be bullet proof,
>> > their would probably be a lot more force on the flaps though. I
>> > haven't been able to find information if the necessary airplane
>> > hardware is available commercially, perhaps it would have to be custom
>> > made. Any ideas on how to go about building something like this?
>> >
>> > Brock
>>
>> Whereas the Helio Courier and Morane Rallye (among others), and their
>> slats, are discussed elsewhere in the thread; I'll just mention that all
>> of the high wing Cessna aircraft with which I am familiar have single
>> slotted Fowler flaps. I have no idea how much performance you would
>> gain with double slotted Fowler flaps, and doubt that they would add
>> much weight; but believe that they would be a real pain in the neck to
>> build s the dimensions would need to be held closely in order for the
>> slots to have the correct proportions and the additional surfaces would
>> need to be finished.
>>
>> Peter

[Richard Lamb]

One of the NACA Research Memorandum covers what could be the F-104
wing design. Check out "The Effects of Leading Edge Flap Upon
the Lift, Drag, and pitching moment of and airplane employing a
thin, Unswept wing".

It doesn't mention "blowing" the wing, tho.

Richard

Big John wrote:
>
> The F-104 had both leading and trailing edge flaps and wing was
> 'blown'.
>
> Big John
> Mach 1+
>
> On Sat, 26 Jul 2003 02:51:21 GMT, Richard Lamb >
> wrote:
>
> >Steve Wittman had leading edge FLAPS (not slats) on his Buttercup.
> >Buttercup is a predecessor to the Wittman Tailwind.
> >That was back in the early '50s?
> >
> >Anyway, the idea is to have a thin wing for high speed cruise and
> >recontour it into an undercambered thin wing to slow down for landing.
> >
> >Thin airfoils tend to have low CLmax while recurred thin airfoils
> >can have amazingly high CLmax.
> >
> >Taken to an extreme, the "sail" type single surfaced ultralight wings
> >show a CLmax of over 4(!)
> >
> >Leading edge flaps are always(?) deployed in conjunction with trailing
> >edge flaps of some kind. Even if it is a simple split flap.
> >
> >Otherwise, the CP would move way forward, and the chord line suddenly
> >goes the wrong way.
> >
> >Earl Luce built the first replica Buttercup (and sells plans fo it too).
> >
> >Earl said Buttercup lands in the low 40s with the flaps down.
> >Or over 70 (with a lot of skipping and skating) without them.
> >
> >I did a little browsing at the NACA server and found a lot of info on
> >leading edge flaps. But it all seemed more applicable to supersonic and
> >high subsonic heavies.
> >
> >To date, Buttercup is the only light plane I know of that has leading
> >edge flaps.
> >
> >Richard
> >
> >
> >Peter Dohm wrote:
> >>
> >> Brock wrote:
> >> >
> >> > I feel there is a real advantage to the use of slats and flaps in
> >> > order to have things happen slowly during landing and yet still have a
> >> > good cruise speed. Of course the problem is in the complexity and the
> >> > extra weight. For rails I was thinking about something like standard
> >> > kitchen drawer rails or perhaps a tube within a tube design. I
> >> > wouldn't think their would be a lot of force on the slat at low
> >> > takeoff speeds so the structure wouldn't have to be bullet proof,
> >> > their would probably be a lot more force on the flaps though. I
> >> > haven't been able to find information if the necessary airplane
> >> > hardware is available commercially, perhaps it would have to be custom
> >> > made. Any ideas on how to go about building something like this?
> >> >
> >> > Brock
> >>
> >> Whereas the Helio Courier and Morane Rallye (among others), and their
> >> slats, are discussed elsewhere in the thread; I'll just mention that all
> >> of the high wing Cessna aircraft with which I am familiar have single
> >> slotted Fowler flaps. I have no idea how much performance you would
> >> gain with double slotted Fowler flaps, and doubt that they would add
> >> much weight; but believe that they would be a real pain in the neck to
> >> build s the dimensions would need to be held closely in order for the
> >> slots to have the correct proportions and the additional surfaces would
> >> need to be finished.
> >>
> >> Peter

[Big John]

Richard

Bird landed with some power on engine to provide bleed air to wing. We
had some check outs that flared and pulled the throttle to idle while
still in the air and the bird dropped in. Some of these caused damage
to bird.

Go to Google and search for "F-104 blown wing" and see the details.

Big John

On Sat, 26 Jul 2003 20:09:07 GMT, Richard Lamb >
wrote:

>One of the NACA Research Memorandum covers what could be the F-104
>wing design. Check out "The Effects of Leading Edge Flap Upon
>the Lift, Drag, and pitching moment of and airplane employing a
>thin, Unswept wing".
>
>It doesn't mention "blowing" the wing, tho.
>
>Richard
>
>Big John wrote:
>>
>> The F-104 had both leading and trailing edge flaps and wing was
>> 'blown'.
>>
>> Big John
>> Mach 1+
>>
>> On Sat, 26 Jul 2003 02:51:21 GMT, Richard Lamb >
>> wrote:
>>
>> >Steve Wittman had leading edge FLAPS (not slats) on his Buttercup.
>> >Buttercup is a predecessor to the Wittman Tailwind.
>> >That was back in the early '50s?
>> >
>> >Anyway, the idea is to have a thin wing for high speed cruise and
>> >recontour it into an undercambered thin wing to slow down for landing.
>> >
>> >Thin airfoils tend to have low CLmax while recurred thin airfoils
>> >can have amazingly high CLmax.
>> >
>> >Taken to an extreme, the "sail" type single surfaced ultralight wings
>> >show a CLmax of over 4(!)
>> >
>> >Leading edge flaps are always(?) deployed in conjunction with trailing
>> >edge flaps of some kind. Even if it is a simple split flap.
>> >
>> >Otherwise, the CP would move way forward, and the chord line suddenly
>> >goes the wrong way.
>> >
>> >Earl Luce built the first replica Buttercup (and sells plans fo it too).
>> >
>> >Earl said Buttercup lands in the low 40s with the flaps down.
>> >Or over 70 (with a lot of skipping and skating) without them.
>> >
>> >I did a little browsing at the NACA server and found a lot of info on
>> >leading edge flaps. But it all seemed more applicable to supersonic and
>> >high subsonic heavies.
>> >
>> >To date, Buttercup is the only light plane I know of that has leading
>> >edge flaps.
>> >
>> >Richard
>> >
>> >
>> >Peter Dohm wrote:
>> >>
>> >> Brock wrote:
>> >> >
>> >> > I feel there is a real advantage to the use of slats and flaps in
>> >> > order to have things happen slowly during landing and yet still have a
>> >> > good cruise speed. Of course the problem is in the complexity and the
>> >> > extra weight. For rails I was thinking about something like standard
>> >> > kitchen drawer rails or perhaps a tube within a tube design. I
>> >> > wouldn't think their would be a lot of force on the slat at low
>> >> > takeoff speeds so the structure wouldn't have to be bullet proof,
>> >> > their would probably be a lot more force on the flaps though. I
>> >> > haven't been able to find information if the necessary airplane
>> >> > hardware is available commercially, perhaps it would have to be custom
>> >> > made. Any ideas on how to go about building something like this?
>> >> >
>> >> > Brock
>> >>
>> >> Whereas the Helio Courier and Morane Rallye (among others), and their
>> >> slats, are discussed elsewhere in the thread; I'll just mention that all
>> >> of the high wing Cessna aircraft with which I am familiar have single
>> >> slotted Fowler flaps. I have no idea how much performance you would
>> >> gain with double slotted Fowler flaps, and doubt that they would add
>> >> much weight; but believe that they would be a real pain in the neck to
>> >> build s the dimensions would need to be held closely in order for the
>> >> slots to have the correct proportions and the additional surfaces would
>> >> need to be finished.
>> >>
>> >> Peter

[Bill Higdon]

The F4-E's originally blown leading edge flaps (drooping leading edge),
in early to mid 1970's they were refitted with leading edge slats. Which
were controlled by a black box and interconnected so you didn't have one
out and one in, like the DC-10 that crashed in Chicago did.
Bill Higdon
Big John wrote:
> Richard
>
> Bird landed with some power on engine to provide bleed air to wing. We
> had some check outs that flared and pulled the throttle to idle while
> still in the air and the bird dropped in. Some of these caused damage
> to bird.
>
> Go to Google and search for "F-104 blown wing" and see the details.
>
> Big John
>
> On Sat, 26 Jul 2003 20:09:07 GMT, Richard Lamb >
> wrote:
>
>
>>One of the NACA Research Memorandum covers what could be the F-104
>>wing design. Check out "The Effects of Leading Edge Flap Upon
>>the Lift, Drag, and pitching moment of and airplane employing a
>>thin, Unswept wing".
>>
>>It doesn't mention "blowing" the wing, tho.
>>
>>Richard
>>
>>Big John wrote:
>>
>>>The F-104 had both leading and trailing edge flaps and wing was
>>>'blown'.
>>>
>>>Big John
>>>Mach 1+
>>>
>>>On Sat, 26 Jul 2003 02:51:21 GMT, Richard Lamb >
>>>wrote:
>>>
>>>
>>>>Steve Wittman had leading edge FLAPS (not slats) on his Buttercup.
>>>>Buttercup is a predecessor to the Wittman Tailwind.
>>>>That was back in the early '50s?
>>>>
>>>>Anyway, the idea is to have a thin wing for high speed cruise and
>>>>recontour it into an undercambered thin wing to slow down for landing.
>>>>
>>>>Thin airfoils tend to have low CLmax while recurred thin airfoils
>>>>can have amazingly high CLmax.
>>>>
>>>>Taken to an extreme, the "sail" type single surfaced ultralight wings
>>>>show a CLmax of over 4(!)
>>>>
>>>>Leading edge flaps are always(?) deployed in conjunction with trailing
>>>>edge flaps of some kind. Even if it is a simple split flap.
>>>>
>>>>Otherwise, the CP would move way forward, and the chord line suddenly
>>>>goes the wrong way.
>>>>
>>>>Earl Luce built the first replica Buttercup (and sells plans fo it too).
>>>>
>>>>Earl said Buttercup lands in the low 40s with the flaps down.
>>>>Or over 70 (with a lot of skipping and skating) without them.
>>>>
>>>>I did a little browsing at the NACA server and found a lot of info on
>>>>leading edge flaps. But it all seemed more applicable to supersonic and
>>>>high subsonic heavies.
>>>>
>>>>To date, Buttercup is the only light plane I know of that has leading
>>>>edge flaps.
>>>>
>>>>Richard
>>>>
>>>>
>>>>Peter Dohm wrote:
>>>>
>>>>>Brock wrote:
>>>>>
>>>>>>I feel there is a real advantage to the use of slats and flaps in
>>>>>>order to have things happen slowly during landing and yet still have a
>>>>>>good cruise speed. Of course the problem is in the complexity and the
>>>>>>extra weight. For rails I was thinking about something like standard
>>>>>>kitchen drawer rails or perhaps a tube within a tube design. I
>>>>>>wouldn't think their would be a lot of force on the slat at low
>>>>>>takeoff speeds so the structure wouldn't have to be bullet proof,
>>>>>>their would probably be a lot more force on the flaps though. I
>>>>>>haven't been able to find information if the necessary airplane
>>>>>>hardware is available commercially, perhaps it would have to be custom
>>>>>>made. Any ideas on how to go about building something like this?
>>>>>>
>>>>>>Brock
>>>>>
>>>>>Whereas the Helio Courier and Morane Rallye (among others), and their
>>>>>slats, are discussed elsewhere in the thread; I'll just mention that all
>>>>>of the high wing Cessna aircraft with which I am familiar have single
>>>>>slotted Fowler flaps. I have no idea how much performance you would
>>>>>gain with double slotted Fowler flaps, and doubt that they would add
>>>>>much weight; but believe that they would be a real pain in the neck to
>>>>>build s the dimensions would need to be held closely in order for the
>>>>>slots to have the correct proportions and the additional surfaces would
>>>>>need to be finished.
>>>>>
>>>>>Peter
>>>>
>

[Richard Isakson]

"Bill Higdon" wrote ...
> The F4-E's originally blown leading edge flaps (drooping leading edge),
> in early to mid 1970's they were refitted with leading edge slats. Which
> were controlled by a black box and interconnected so you didn't have one
> out and one in, like the DC-10 that crashed in Chicago did.

The last F4 that I saw was at a local military airshow four or five years
ago. It had fixed leading edge slats bolted on to the outboard wing panels.
The pilot said it was a Wild Weasel airplane and one of the last F4s left in
the inventory. I'm sure it's been retired by now.

Rich

[Roger Halstead]

On 25 Jul 2003 06:51:08 -0700, (Brock) wrote:

>I feel there is a real advantage to the use of slats and flaps in

Slats can work great, but they are a double edged sword. They have to
come out together...Not even one a second earlier than the other. The
Germans had a devil of a time with them on their early attempts.

Then those suckers come out, they come out *now* with plenty of force.

As to fowler flaps, I'm going to have them on the G-III. The factory
makes a kit to replace the standard flaps and they do shave a few
knots off the landing speed.

>order to have things happen slowly during landing and yet still have a
>good cruise speed. Of course the problem is in the complexity and the
>extra weight. For rails I was thinking about something like standard
>kitchen drawer rails or perhaps a tube within a tube design. I
>wouldn't think their would be a lot of force on the slat at low

When they hit the end of their travel they are really moving. They
"snap" out. Going back in is no biggie from the force standpoint, but
like extension they have to go back in together.

>takeoff speeds so the structure wouldn't have to be bullet proof,
>their would probably be a lot more force on the flaps though. I

Typically the only ones I've seen were on a curved track and
counterbalanced. If there is an F-84 in your neighborhood, see if
they will let you take a look at how the slats work.

It's one of those simple concepts that works great and can be
difficult to implement.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)

>haven't been able to find information if the necessary airplane
>hardware is available commercially, perhaps it would have to be custom
>made. Any ideas on how to go about building something like this?
>
>Brock

[Dave Hyde]

Big John wrote:

> Only some series of the F-86 had slats. They found in Korea a problem
> with them (may have not come out together and threw aim off or
> something when pulling 'G's'). They changed in the "F" model to a
> solid wing without any slats.

As I always like to point out when aero-deployed slats come
up in the newsgroup, A-4's had 'em too. The Blue Angels
wired 'em retracted to prevent 'bobbles' when maneuvering
in close formation. Aggressors, IIRC, wired them up too.
SOP for most any flight was a slat ops check before maneuvering.
I've written here before about asymmetric slat departures, and know
at least on person who jumped out of an otherwise perfectly good
jet after having one stick in and cause a departure at the top
of a loop. I didn't know they got rid of them on the F-86,
that's interesting.

I'm not a big fan of them and have fought to keep them out of
designs where I've had input. I still can't see a reason for
not having an interconnect that outweighs safety of flight.

Dave 'thunk *crack*' Hyde

[Big John]

Dave

They had them on the T-39 which I flew a little. Seemed to work ok on
the light transport.

Only thing I can remember was running a practice GCA on arrivial at
Tyndall AFB, FL, and the air speed was right at the slots out speed.
Was summer time and some turblance and slats kept banging in and out
against stops. We just picked up 5 MPH or so and they stayed retracted
until we slowed down on glide slope and they extended. Work around
was not a problem.

Only other bird I flew with slats was the Helio Courier (U-10). Again
not a problem as we adjusted our A/S up or down to pervent 'banging'
of slats in rough air at slats out A/S.

Big John

On Mon, 28 Jul 2003 23:15:01 GMT, Dave Hyde > wrote:

>Big John wrote:
>
>> Only some series of the F-86 had slats. They found in Korea a problem
>> with them (may have not come out together and threw aim off or
>> something when pulling 'G's'). They changed in the "F" model to a
>> solid wing without any slats.
>
>As I always like to point out when aero-deployed slats come
>up in the newsgroup, A-4's had 'em too. The Blue Angels
>wired 'em retracted to prevent 'bobbles' when maneuvering
>in close formation. Aggressors, IIRC, wired them up too.
>SOP for most any flight was a slat ops check before maneuvering.
>I've written here before about asymmetric slat departures, and know
>at least on person who jumped out of an otherwise perfectly good
>jet after having one stick in and cause a departure at the top
>of a loop. I didn't know they got rid of them on the F-86,
>that's interesting.
>
>I'm not a big fan of them and have fought to keep them out of
>designs where I've had input. I still can't see a reason for
>not having an interconnect that outweighs safety of flight.
>
>Dave 'thunk *crack*' Hyde

[Dave Hyde]

Big John wrote:

> They had them on the T-39 which I flew a little. Seemed to work ok on
> the light transport.

Was it the T-39 that had them in sections, like 2 per wing, so
that there were four altogether that could deploy at seemingly random
intervals? <g>

> Was summer time and some turblance and slats kept banging in and out
> against stops.

Gouge in the A-4 was that 1/2 slat extension was on-speed AOA in the
landing configuration. I never saw an AOA failure (very little time
in 'em, all in the back seat of T's), but I understand it could be
worked into your scan with some difficulty.

Dave 'swivelneck' Hyde

[Big John]

Dave

Not sure. Was over 30 years ago. They hung out on the ground and
remember pushing them into the retracted position and they would fall
out by their own weight, on pre flight. Want to say they were one
piece but ????????????????????

I never kept a Dash One on the T-39 so can't go there in my files to
answer your question. Didn't find anything via Google on the
construction of the slats. Just that they had them :o(


Big John



On Tue, 29 Jul 2003 01:00:35 GMT, Dave Hyde > wrote:

>Big John wrote:
>
>> They had them on the T-39 which I flew a little. Seemed to work ok on
>> the light transport.
>
>Was it the T-39 that had them in sections, like 2 per wing, so
>that there were four altogether that could deploy at seemingly random
>intervals? <g>
>
>> Was summer time and some turblance and slats kept banging in and out
>> against stops.
>
>Gouge in the A-4 was that 1/2 slat extension was on-speed AOA in the
>landing configuration. I never saw an AOA failure (very little time
>in 'em, all in the back seat of T's), but I understand it could be
>worked into your scan with some difficulty.
>
>Dave 'swivelneck' Hyde

[Roger Halstead]

On Mon, 28 Jul 2003 15:29:14 -0500, Big John >
wrote:

>Roger
>
>Only some series of the F-86 had slats. They found in Korea a problem
>with them (may have not come out together and threw aim off or
>something when pulling 'G's'). They changed in the "F" model to a
>solid wing without any slats.
>
Thanks for the info John. I had never heard about the change.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
>Quote from Internet:
>
>"Replacing the earlier 'A' and 'E' models the 'F' featured a new '6 -
>3' wing without the slats found on the leading edge of the earlier
>models. The increased chord of the wing (6 inches at the root and 3
>inches at the tip) and small boundry layer fences gave better
>maneuvering at high speed"

[Big John]

Richard

I sure don't remember 5 sections on each wing but so long ago. However
after 'sleeping' on it they well could have had 5 sections??? Would be
easier to build and keep operational (short sections) than one long
section. Next time I see one that I can get up to will look to
refresh my memory. Maybe someone on r.a.h. might see one and be able
to post what the hardware was.

On deicer boots. Don't think the Air Force ever bought any equipped
that way. Never saw on any of the T-39's I was around.

As an engineer looking at the wing with slats, I don't see how they
could have put boots on and still retained the slats???? Never heard
of a hard wing T-39.

Hope all at Osh have a good time and get home safely. That includes
those drinking "muzzle loader" <G>

Big John

On Mon, 28 Jul 2003 21:18:41 -0700, "Richard Isakson"
> wrote:

>"Big John" wrote ...
>> Not sure. Was over 30 years ago. They hung out on the ground and
>> remember pushing them into the retracted position and they would fall
>> out by their own weight, on pre flight. Want to say they were one
>> piece but ????????????????????
>>
>> I never kept a Dash One on the T-39 so can't go there in my files to
>> answer your question. Didn't find anything via Google on the
>> construction of the slats. Just that they had them :o(
>
>According to the 1969-70 Janes:
>
>"North American
>
>T-39
>
>Wings:
>Aerodynamically-operated leading-edge slats in five sections on each wing.
>Optional full-span pneumatically-operated de-icer boots."
>
>Now there's an interesting trick.
>
>Rich
>
>

[CF]

"Brock" > a écrit dans le message news:
...
> I feel there is a real advantage to the use of slats and flaps in
> order to have things happen slowly during landing and yet still have a
> good cruise speed. Of course the problem is in the complexity and the
> extra weight. For rails I was thinking about something like standard
> kitchen drawer rails or perhaps a tube within a tube design. I
> wouldn't think their would be a lot of force on the slat at low
> takeoff speeds so the structure wouldn't have to be bullet proof,
> their would probably be a lot more force on the flaps though. I
> haven't been able to find information if the necessary airplane
> hardware is available commercially, perhaps it would have to be custom
> made. Any ideas on how to go about building something like this?
>
> Brock

I fear that if flaps has some aerodynamic effect, they HAVE to be bullet
proof.
Just imagine what could happen in cas of disymetrical openning. Or one side
flap locked in landing configuration, the other side retracting. I dont
think aileron whould have enought authority to overcome the roll.

And for fowler flaps, I unterstand it is the ones that go aft before
rotating.

What about ordinary rotating flaps, but with a very low rotation points. Say
rotation point one feet below the wing. at 45° extention, the leading edge
of the flap would be (sin (45°)) aft. No need for rails. A bunch of slotted
flaps on certified planes just act like this.

Other point to consider are:
->Tail should have enough authority to compensate the pitching moment.
->your plane should have enough power to have a positive climb rate, at full
load with flaps, fowlers, landing gear fully extented.

[Mike Weller]

On Mon, 28 Jul 2003 21:18:41 -0700, "Richard Isakson"
> wrote:

>"Big John" wrote ...
>> Not sure. Was over 30 years ago. They hung out on the ground and
>> remember pushing them into the retracted position and they would fall
>> out by their own weight, on pre flight. Want to say they were one
>> piece but ????????????????????
>>

It's been a long time for me also, but I'm sure the slats were one
piece, with five roller guides per wing. I've never seen a de-ice
boot on one.

An interesting story that I heard, again a long time ago, was from a
pilot that had flown the F-86D and got checked out in the T-39. The
wings look a lot the same, and the plane flew about the same. Well,
they would roll and loop and dogfight the T-39s until they found out
that they were only designed for something like 3.8 Gs.

Mike Weller

[Big John]

Mike

Your comments on slats now seem to track with what I remember.

I flew the 'D','H' & 'J' at Hamilton and the 'J' as AFA to Maine ANG
(Bangor, ME). Flying the 'J' I've launched a MB-1, in practice, past
vertical and just above the stall speed. (IFR at night in the middle
of the clouds). Interesting flying the bird back to level flight
starting with zero A/S and going straight up IFR<G>

On '39. Was told that the wing came off the F-86 line (no new
engineering) and was tough as hell. Where the lower limits were on
bird I don't know but know they were there. Always flew the '39 as a
transport not as a fighter as always had passengers on board, unless
repositioning bird. It was the General's personal bird so we couldn't
tear it up very bad (go inverted and spill the coffee <G>.

Miss the 'old' days

Big John


On Thu, 31 Jul 2003 18:31:17 GMT, Mike Weller >
wrote:

>On Mon, 28 Jul 2003 21:18:41 -0700, "Richard Isakson"
> wrote:
>
>>"Big John" wrote ...
>>> Not sure. Was over 30 years ago. They hung out on the ground and
>>> remember pushing them into the retracted position and they would fall
>>> out by their own weight, on pre flight. Want to say they were one
>>> piece but ????????????????????
>>>
>
>It's been a long time for me also, but I'm sure the slats were one
>piece, with five roller guides per wing. I've never seen a de-ice
>boot on one.
>
>An interesting story that I heard, again a long time ago, was from a
>pilot that had flown the F-86D and got checked out in the T-39. The
>wings look a lot the same, and the plane flew about the same. Well,
>they would roll and loop and dogfight the T-39s until they found out
>that they were only designed for something like 3.8 Gs.
>
>Mike Weller

[B2431]

>
>It's been a long time for me also, but I'm sure the slats were one
>piece, with five roller guides per wing. I've never seen a de-ice
>boot on one.
>

I saw them on a USMC or Navy T-39 in the mid 1990s. I bet they add a ton of
drag.

I used to work on A and B model T-39s at Langley AFB in the mid 70s. The slats
may have been made up of 5 segments each, but they were one piece as far as I
could tell. They pushed in as one anyway.

Dan, U.S. Air Force, retired