WW2 Drop Tanks
Ken S. Tucker
welcome.
I understand that during the Battle of Britain, the 109's
had 15-20 minutes dogfight combat time over London,
and also, had they used cheapo (paper mache) drop
tanks, to give them more combat time and depth, the
Battle of Britain may have been won by the Nazi's.
Furthermore (following Art), drop-tanks used by escort
fighters were decisive in the bombing campaign and thus
the eventual destruction (imputant) rendered to the LW.
What's always seemed funny to me, (funny with all due
respect), is that "paper mache" drop tanks could have
been or may have been decisive. With all the ultra-teky
super-secret weapons, lowly "paper mache" ranks up
there as a decisive common strategic material, perhaps
over-looked because it was too simple?
Ken
Robert Sveinson
"Ken S. Tucker" <dyna...@vianet.on.ca> wrote in message
news:1170633168.6...@j27g2000cwj.googlegroups.com...
> This is a bit off Arts Post. Opinions and corrections
> welcome.
> I understand that during the Battle of Britain, the 109's
> had 15-20 minutes dogfight combat time over London,
> and also, had they used cheapo (paper mache) drop
> tanks, to give them more combat time and depth, the
> Battle of Britain may have been won by the Nazi's.
I have read that the LW tried plywood drop tanks, but can't recall
papier mache. Interesting though!
Geoffrey Sinclair
news:1170633168.6...@j27g2000cwj.googlegroups.com...
> welcome.
> I understand that during the Battle of Britain, the 109's
> had 15-20 minutes dogfight combat time over London,
> and also, had they used cheapo (paper mache) drop
> tanks, to give them more combat time and depth, the
> Battle of Britain may have been won by the Nazi's.
I think you will find the drop tanks the Luftwaffe had experimented
with by 1940 were wooden, and they tended to age rather quickly
unless care was taken. The whole point of drop tanks is to make
them as cheap as possible to last the one mission.
Giving the Bf109s more combat radius in 1940 would have helped
the Luftwaffe's cause, I doubt they would have been that decisive
though.
Also I think you will find paper tanks used things like plastics
as reinforcements or linings to obtain the necessary strength
and inhibit fuel leaks.
> Furthermore (following Art), drop-tanks used by escort
> fighters were decisive in the bombing campaign and thus
> the eventual destruction (imputant) rendered to the LW.
The bombers needed air superiority to be able to mount a
sustainable campaign.
> What's always seemed funny to me, (funny with all due
> respect), is that "paper mache" drop tanks could have
> been or may have been decisive. With all the ultra-teky
> super-secret weapons, lowly "paper mache" ranks up
> there as a decisive common strategic material, perhaps
> over-looked because it was too simple?
There are many reasons why drop tanks are non obvious. From the
fighter pilot's point of view there is the extra weight and drag, plus the
weight of the extra fuel system. The tanks generally impose limits
on what aerobatics the pilot can do and have to be jettisoned correctly.
There can also be altitude limits on when the fuel can be drawn from
external tanks.
From the air force point of view unless they are used before dropping
the fuel in them is wasted. Furthermore you need to prove the extra
range is desirable, and if you do the more desirable situation is to
increase internal fuel storage. In 1940 the Germans had a long range
fighter, the Bf110 then found it was not suitable. The Battle of Britain
was too short a time to introduce major changes.
The IJN had learnt the lesson fighters needed bomber like ranges from
the fighting over China, hence the good range built into the A6M which
was further improved by experiments by the pilots. The European air
forces needed the fighting in 1939 and in particular 1940 to have the
irrefutable evidence.
Note how long it then took for fighter ranges to go up.
Information from Mighty Eighth War manual by Freeman (US gallons)
nominal capacity, real capacity, material, source,
75 / 84 / Steel / US
108 / 108 / Steel / UK
108 / 108 / Paper / UK
110 / 110 / Steel / US
150 / 165 / Steel / US (There were 2 models of these)
150 / 165 / Steel / UK
165 / 165 / Steel / US
200 / 205 / Paper / US
200 / 215 / Steel / UK
Information from Spitfire by Morgan and Shacklady, page 150
Spitfire and Seafire blister drop tanks, capacity in imperial gallons /
constructor / material / designer.
30 / Vickers / tinned steel / Vickers
30 / Essex Aero / welded elektron / Vickers
30 / Vulcanised Fibre / vulcanised fibre / Vickers
30 / Smith Meters / tinned steel / RAE
30 / Southern Aircraft / 3-ply / RAE
30 / Stanley Smith / 3-ply / RAE
30 / Saro Laminated Wood / laminated wood / RAE
45 / Vickers / tinned steel / Vickers
45 / Stanley Smith / 3-ply / RAE
90 / Vickers / tinned steel / Vickers
90 / Saro Laminated Wood / laminated wood / RAE
90 / Auto Metalcraft / laminated wood / RAE
90 / Stanley Smith / 3-ply / RAE
90 / Vulcanised Fibre / vulcanised fibre / Vickers
170 / Boulton and Paul / welded steel / Boulton and Paul
Geoffrey Sinclair
Remove the nb for email.
WaltBJ
materials nor were the expended ones worth salvaging. They also had to
be flown and used right after fueling since they deteriorated quickly
from the action of the fuel.
Walt BJ
Ken S. Tucker
On Feb 4, 7:15 pm, "Geoffrey Sinclair" <gsinclai...@froggy.com.au>
wrote:
> "Ken S. Tucker" <dynam...@vianet.on.ca> wrote in messagenews:1170633168.6...@j27g2000cwj.googlegroups.com...
>
> > This is a bit off Arts Post. Opinions and corrections
> > welcome.
> > I understand that during the Battle of Britain, the 109's
> > had 15-20 minutes dogfight combat time over London,
> > and also, had they used cheapo (paper mache) drop
> > tanks, to give them more combat time and depth, the
> > Battle of Britain may have been won by the Nazi's.
>
> I think you will find the drop tanks the Luftwaffe had experimented
> with by 1940 were wooden, and they tended to age rather quickly
> unless care was taken. The whole point of drop tanks is to make
> them as cheap as possible to last the one mission.
>
> Giving the Bf109s more combat radius in 1940 would have helped
> the Luftwaffe's cause, I doubt they would have been that decisive
> though.
Let me use "rule-of-thumb", an Me-109 uses 1/3
it's fuel to get to Britain, 1/3 in combat and 1/3
to get home. My question will follow,
The drop tanks would have provided the Me-109's
to enter combat fully fueled, making the A/C heavier,
so the loss in maneuverability due to that extra mass,
may have entered into the desicion to reduce dwell
time, in favor of a lighter combat machine.
I would have favored dwell time over manuevability,
but, if the fully fueled Me-109 was a pig to fly against
the Spits and Hurks' then I suppose "drop tanks" ain't
a good idea.
Either way makes sense to me.
Ken
Gernot Hassenpflug
I'm sorry, that does not make sense. An aircraft is designed to fight
with a full fuel load, not with a half-empty one. Are you suggesting
that the designers of fighter aircraft made the machines less useful
if they were fully fueled. And that they became measureably better
combat aircraft as their tanks emptied? One could certainly affect
longitudinal stability and need to adjust as the fuel drained, but I
very much doubt that with the engines in use at the time the fuel load
would have made a difference to performance. Certainly pilot peace of
mind is highly in favour of more fuel - would you pull fuel-draining
combat manouevres if you had only a light fuel load? :-)
--
BOFH excuse #387:
Your computer's union contract is set to expire at midnight.
Kyle Boatright
"Gernot Hassenpflug" <ger...@mb3.seikyou.ne.jp> wrote in message
news:87odo8n...@fukaolx15.rish.kuins.net...
There is no doubt that more combat persistence in the Me-109 would have
benefited the Germans in the BOB, but that alone wouldn't have turned the
battle. In the final analysis, the Germans attacked an opponent which had a
magic weapon (radar), equivalent aircraft quality, and closer basing which
gave the ability for the British fighters to intercept multiple raids in a
day.. These factors balanced out Germany's superiority in numbers. Beyond
that the Germans' superiority in numbers was diminished as the battle went
on, because the Brits were replacing pilots and planes faster than the
Germans were. Also, the Germans took the Ju-87's out of the battle for the
most part and diminished the role of the 110's, further helping eroding the
Luftwaffe's effective strength.
As to the fuel load vs aircraft performance issue, fuel made up 10 to 15 %
of the all up weight of an early Spit, Hurri, or 109. Burn off 1/2 or 2/3 of
the fuel and performance increases mesurably.. The most noticable
difference won't be in turn radius, it'll be in climb rate or acceleration.
FYI, I fly an aircraft which has roughly half the power to weight ratio as a
Spit, Hurri, or 109, and a 10% weight difference makes a huge difference in
the aircraft's performance.
Henry J Cobb
> I'm sorry, that does not make sense. An aircraft is designed to fight
> with a full fuel load, not with a half-empty one. Are you suggesting
> that the designers of fighter aircraft made the machines less useful
> if they were fully fueled. And that they became measureably better
> combat aircraft as their tanks emptied? One could certainly affect
> longitudinal stability and need to adjust as the fuel drained, but I
> very much doubt that with the engines in use at the time the fuel load
> would have made a difference to performance. Certainly pilot peace of
> mind is highly in favour of more fuel - would you pull fuel-draining
> combat manouevres if you had only a light fuel load? :-)
http://www.airtoaircombat.com/background.asp?bg=619&id=181
However, this extra fuel tank moved the center of gravity aft, which
made the directional stability of the Mustang quite poor, so that the
pilot would have to spend the first hour or so concentrating on keeping
his airplane pointed in the right direction until this new tank was
finally empty.
-HJC
Howard Austin
With the Mustang's (P-51D) aft tank full (85 US Gallons) the aircraft
was unstable along the lateral axis, not the vertical, as you suggest.
However, after burning 35 gallons, about 30 minutes,the aircraft
became completely stable. When the P-51H was designed the tank capacity
was reduced to 50 gallons, eliminating the problem. Flew them both.
Howard Austin
Stephen Harding
> With the Mustang's (P-51D) aft tank full (85 US Gallons) the aircraft
> was unstable along the lateral axis, not the vertical, as you suggest.
> However, after burning 35 gallons, about 30 minutes,the aircraft
> became completely stable. When the P-51H was designed the tank capacity
> was reduced to 50 gallons, eliminating the problem. Flew them both.
Which version did you like the best (to fly) and which one
would you prefer to be in combat with?
I know quite a few pilots seemed to like the B/C over the
D/K but I would think it a tossup: A little faster speed
(can't remember if it was straight out or in a dive) and
more stability with B versus longer range and more
firepower with the D.
Don't know much about the H except that it looks uglier
than the D to me.
SMH
Geoffrey Sinclair
> Let me use "rule-of-thumb", an Me-109 uses 1/3
> it's fuel to get to Britain, 1/3 in combat and 1/3
> to get home. My question will follow,
> The drop tanks would have provided the Me-109's
> to enter combat fully fueled, making the A/C heavier,
> so the loss in maneuverability due to that extra mass,
> may have entered into the desicion to reduce dwell
> time, in favor of a lighter combat machine.
In essence this was the RAF objection to a long range fighter, the
fact it would have a significant extra weight of fuel versus the
presumed shorter range interceptor it would meet.
The Germans thought a twin engined machine was needed in the
role of long range fighter.
The Spitfire I carried around 610 pounds of fuel, which around 10%
of the loaded weight. So it is sort of hard to see another 5% being
that critical. Especially given in the Battle of Britain the RAF fighters
would have had more fuel on board, as a percentage of the total
tankage, when fighting than the average Bf109.
It should be noted some 73 pounds of armour was added during
the mark I production run and by the mark VIII it was up to 202
pounds.
> I would have favored dwell time over manuevability,
> but, if the fully fueled Me-109 was a pig to fly against
> the Spits and Hurks' then I suppose "drop tanks" ain't
> a good idea.
As far as I am aware the Bf109 performance, like that of the Spitfire
and Hurricane did not drop off dramatically as the fuel tanks were
filled. Later in the war the rear fuselage tanks on Mustangs and
Spitfires did affect performance.
> Either way makes sense to me.
The RAF allowed 23 gallons for the Spitfire VIII to warm up, take off
and climb to 20,000 feet, if you like this would be the minimum drop
tank size. It would be slightly more than 25% of the 1940 Bf109E fuel
load.
So something around a 30 gallon external tank, or about 1/3 the internal
tankage, would have enabled the Bf109 to reach the English coast with
full internal tanks. I doubt an extra 200 pounds of fuel on board would
have made that big a difference to Bf109 combat ability and would most
probably cut casualties, given the anecdotal evidence of the number
of Bf109s said to have run out of fuel on the way home.
Howard Austin
Stephen Harding <smhar...@msn.com> wrote:
> Howard Austin wrote:
>
> > With the Mustang's (P-51D) aft tank full (85 US Gallons) the aircraft
> > was unstable along the lateral axis, not the vertical, as you suggest.
> > However, after burning 35 gallons, about 30 minutes,the aircraft
> > became completely stable. When the P-51H was designed the tank capacity
> > was reduced to 50 gallons, eliminating the problem. Flew them both.
>
> Which version did you like the best (to fly)
The H by far. Much lighter airframe with lighter stick forces, felt
almost as if it had boosted controls compared to the D. Don't mis-
understand, both were a joy to fly, demanding at times however.
and which one would you prefer to be in combat with?
I would prefer to not be in combat with either. But having survived a
tour in the D I can't believe the H could have served me better.
>
> I know quite a few pilots seemed to like the B/C over the
> D/K but I would think it a tossup: A little faster speed
> (can't remember if it was straight out or in a dive) and
> more stability with B versus longer range and more
> firepower with the D.
>
> Don't know much about the H except that it looks uglier
> than the D to me.
The F-89 was ugly, any Mustang is a thing of beauty.
Howaard Austin
>
>
> SMH
Max Richter
There a D-Model Mustang crashed in the alps with a displaypilot on route
to an airshow.
Probably reason was that the pilot, self owner of an D-Model, flew the
airplane of a friend
which was a D-model but from a different manufakturer.
In this report was a indept discription that first the instruments where
different especially the speedometer which in the
aircraft which was owned by the pilot was calibrated in nautical miles
and in the accidentplane in statutemiles.
But that the center of graviti was seriously different because of a
differned installation of the battery inside of the planes.
So it s seems that you have not only to look after the model but also
after the actual manufacturer to determine the flying charakteristiks of
a certain airplane.
Greetings Max
Howard Austin schrieb:
Jack
> I recall reading an accidentreport from switzerland two or three years
> ago.
> There a D-Model Mustang crashed in the alps with a displaypilot on route
> to an airshow.
> Probably reason was that the pilot, self owner of an D-Model, flew the
> airplane of a friend which was a D-model but from a different manufakturer.
>
> In this report was a indept discription that first the instruments where
> different especially the speedometer which in the
> aircraft which was owned by the pilot was calibrated in nautical miles
> and in the accidentplane in statutemiles.
> But that the center of graviti was seriously different because of a
> differned installation of the battery inside of the planes.
> So it s seems that you have not only to look after the model but also
> after the actual manufacturer to determine the flying charakteristiks of
> a certain airplane.
And, we are left with the highly imperfect accident reporting and
fault analysis process which may look to differences in a/c manuals,
without any possible reference to the actual experience of flying
the two aircraft comparatively, because that is all they have to
work with. How many on the accident board will have had any time in
51's?
I would not expect that such relatively minor differences would be
enough to cause the loss of an aircraft in the enroute phase of a
flight.
I hope that those who have experience with various P/F-51's will
comment further for our edification.
Jack
Orval Fairbairn
Jack <baro...@yahoo.com> wrote:
An individual P-51, over 60 years of military/civil ownership, may have
undergone significant configuration changes to cockpit layout,
instrumentation -- even engine modifications, that is a completely
different-flying airplane from one that rolled down the production line
in 1945.
In the 1960s Cavalier modified (and certificated) a number of them as
civilian high-speed transportation. They completely reconfigured the
cockpit, added a P-51H fin, upped the power, etc.
So, fuel valves, landing gear and flap selectors, instrumentation may
well have been relocated, so that a complete cockpit checkout was in
order.
Jack
> An individual P-51, over 60 years of military/civil ownership, may have
> undergone significant configuration changes to cockpit layout,
> instrumentation -- even engine modifications, that is a completely
> different-flying airplane from one that rolled down the production line
> in 1945.
>
> In the 1960s Cavalier modified (and certificated) a number of them as
> civilian high-speed transportation. They completely reconfigured the
> cockpit, added a P-51H fin, upped the power, etc.
>
> So, fuel valves, landing gear and flap selectors, instrumentation may
> well have been relocated, so that a complete cockpit checkout was in
> order.
Yes, fuel system mods could certainly do it (cause a loss enroute).
Jack
guy
Yes, similarlry all Battle of Britain Memorial Flight Spitfires are
now A/C rather than D/C I believe, not sure about the Hurricanes
though.
guy
Gernot Hassenpflug
guy> Yes, similarlry all Battle of Britain Memorial Flight
guy> Spitfires are now A/C rather than D/C I believe, not sure
guy> about the Hurricanes though.
Jeez! I spent a few secs thinking what the bureaucracy could've
renamed "aircraft" to now that they are so old :-) Air craft ->
decrepit craft? :-)
--
G Hassenpflug * IJN & JMSDF equipment/history fan
guy
good thing i didnt typo with A/D rather than B/C :-)
guy
Max Richter
the accident occured in worsened weather in a valley. The deceased Pilot
tried aperently to fly an Immelmannturn or something like it to avoid
crashing in a mountain.
The airplane was heard and seen spinning out of cloudcover and did not
recover.
So it is thought the pilot flew slower than normal because of the
different milesreading on the instrument and stalled.
No serious problem on its own, but in adverse weather deadly.
Greeting Max
Sorry about my lousy english
guy schrieb:
Howard Austin
> Max Richter wrote:
> > I recall reading an accidentreport from switzerland two or three years
> > ago.
> > There a D-Model Mustang crashed in the alps with a displaypilot on route
> > to an airshow.
> > Probably reason was that the pilot, self owner of an D-Model, flew the
> > airplane of a friend which was a D-model but from a different manufakturer.
Wouldn't have made any difference, they were al manufactured to the same
specs.
> >
> > In this report was a indept discription that first the instruments where
> > different especially the speedometer which in the
> > aircraft which was owned by the pilot was calibrated in nautical miles
> > and in the accidentplane in statutemiles.
He certainly would have been aware of this.
> > But that the center of graviti was seriously different because of a
> > differned installation of the battery inside of the planes.
For the battery to have a negative influence on the CG it would have to
be located back by the tail wheel. Not likely!
> > So it s seems that you have not only to look after the model but also
> > after the actual manufacturer to determine the flying charakteristiks of
> > a certain airplane.
No! When manufactured they all performed the same, it's all the things
that are done to the bird later in life that one must be aware of.
Howard Austin
>
>
Howard Austin
Orval Fairbairn <orfai...@earthlink.net> wrote:
> In article <lZLzh.8993$O02....@newssvr11.news.prodigy.net>,
> Jack <baro...@yahoo.com> wrote:
>
> > Max Richter wrote:
> > > I recall reading an accidentreport from switzerland two or three years
> > > ago.
> > > There a D-Model Mustang crashed in the alps with a displaypilot on route
> > >
(snip)
>
> An individual P-51, over 60 years of military/civil ownership, may have
> undergone significant configuration changes to cockpit layout,
> instrumentation -- even engine modifications, that is a completely
> different-flying airplane from one that rolled down the production line
> in 1945.
>
> In the 1960s Cavalier modified (and certificated) a number of them as
> civilian high-speed transportation. They completely reconfigured the
> cockpit, added a P-51H fin, upped the power, etc.
One small nit to pick; No P-51H fin was installed, merely an extension
added to the D fin. I flew for Cavalier, flew all their models,
including the Dart powered version. Most enjoyable work.
Howard Austin
guy
> In article <orfairbairn-2F9841.18363311022...@news.west.earthlink.net>,
> Orval Fairbairn <orfairba...@earthlink.net> wrote:
>
> > In article <lZLzh.8993$O02.6...@newssvr11.news.prodigy.net>,
> > Jack <baron...@yahoo.com> wrote:
>
> > > Max Richter wrote:
> > > > I recall reading an accidentreport from switzerland two or three years
> > > > ago.
> > > > There a D-Model Mustang crashed in the alps with a displaypilot on route
>
> (snip)
>
>
>
> > An individual P-51, over 60 years of military/civil ownership, may have
> > undergone significant configuration changes to cockpit layout,
> > instrumentation -- even engine modifications, that is a completely
> > different-flying airplane from one that rolled down the production line
> > in 1945.
>
> > In the 1960s Cavalier modified (and certificated) a number of them as
> > civilian high-speed transportation. They completely reconfigured the
> > cockpit, added a P-51H fin, upped the power, etc.
>
> One small nit to pick; No P-51H fin was installed, merely an extension
> added to the D fin. I flew for Cavalier, flew all their models,
> including the Dart powered version. Most enjoyable work.
>
> Howard Austin
Howard, as someone who actually 'did it' what was the Dart Mustang
like?
guy
Gernot Hassenpflug
:-) FWIW where I come from we don't write the / for any of these
abbrevs.
--
BOFH excuse #168:
le0: no carrier: transceiver cable problem?
Howard Austin
"guy" <guyswe...@googlemail.com> wrote:
First, the Dart was not the engine planned for the bird. The T-55 was the
engine of choice but not not available at the time.
But to answer your question; Quite a bit faster, obviously. More limited
forward visibility on the ground, the engine being lighter, was moved
farther forward to maintain CG. With the extended engine mount I limited
maneuvers to 4g. With the prop turning in the wrong direction torque
effects were reversed. And the list goes on.
Howard Austin
guy
> In article <1171310613.591051.13...@j27g2000cwj.googlegroups.com>,
>
> - Show quoted text -
thanks Howard, one last question, which did you prefer?
guy
Howard Austin
"guy" <guyswe...@googlemail.com> wrote:
> >
> > > Howard, as someone who actually 'did it' what was the Dart Mustang
> > > like?
> >
> > > guy
> >
> > First, the Dart was not the engine planned for the bird. The T-55 was the
> > engine of choice but not not available at the time.
> >
> > But to answer your question; Quite a bit faster, obviously. More limited
> > forward visibility on the ground, the engine being lighter, was moved
> > farther forward to maintain CG. With the extended engine mount I limited
> > maneuvers to 4g. With the prop turning in the wrong direction torque
> > effects were reversed. And the list goes on.
> >
> > Howard Austin- Hide quoted text -
> >
> > - Show quoted text -
>
>
> thanks Howard, one last question, which did you prefer?
>
> guy
Of all the many variants of the Mustang I flew (A-36, P-51D/K/H, all
Cavalier variants) The H was by far my favorite.
Howard Austin
preservemar...@gmail.com
A German researcher friend in the north: Thomas Hampel (now deceased) stored a rare surviving example I had found in France, for me in his family's barn...remarking, "I cannot believe the Americans won the war with such things as this." I told Thomas, "Yes, and win it we did with American ingenuity!" Though I believe the history of the paper mache' tanks is uniquely British while the USAAF engineer Cass Hough fretted over refining a workable drop-tank connection/release and fuel-feed system that would reliably sever upon "drop"...but not during fuel-feed function in flight.
To my knowledge, there are now four known examples of this rare-surviving paper mache' drop tank: one at The Smithsonian Air & Space Museum; another at the U.S. Air Force Museum; I just read about one on exhibit in Ireland...and there is one in my cellar in Holly Springs, Mississippi. It is a 364th Fighter Group specimen. "How do I know this?" I interviewed a French farmer who lived on the outskirts of Remy, France and witnessed the 364th's attack on a suspiciously camouflaged train there on 02 August 1944; saw the top cover flight drop their tanks, preparing to join the attack and...this one landed in his field and for whatever reason, he dragged the damn thing into his barn and there it stayed until I retrieved it in 1998.
Eunometic
It's surprising that the Germans didn't make more of their wooden tanks which I suspect would have been made of cheap plywood with plastic wood fillers. Perhaps their tanks were more often than not recycled.
Bob Martin
>These 'paper Mache' tanks weren't exactly popular and on many cases metal tanks had to be used. I t
>hink their importance is over stated.
>
Grantland
>
> Of all the many variants of the Mustang I flew (A-36, P-51D/K/H, all
> Cavalier variants) The H was by far my favorite.
>
> Howard Austin
kirk....@gmail.com
> I keep reading about the "laminar flow" of the Mustang wing. Are not all foils designed for laminar flow? How else would they work? Or was it just that the Mustang wing had somewhat less turbulence?
Making any metal or fabric covered wing laminar is probably a physical impossibility - you just cant make it smooth enough. I seriously doubt the Mustang wing had much laminar flow, but it probably had a little more than it's contemporaries.
All-turbulent wings work just fine (and actually can have some more pleasant handling characteristics. They just don't glide as well or go as fast.
Kirk
(lots of time in all-turbulent Pawnees and my highly laminar LS6)
Grantland
Grantland
Grantland
kirk....@gmail.com
> > Well there goes my (admittedly intuitive) understanding of the principles of flight. I thought that that bernoulli effect sucked oncoming air over and down the curve, giving it a down vector (and momentum), and by Newton's third, lifting the wing. So does turbulence just leave low pressure behind the high-point and drag the upper air down/suck the wing up? Or does the turbulence roll the air downward in eddies, thus giving Newton lift to the wing?
>
> Ah circulation, kutta condition, vortices Bernoulli - that's turbulent lift. Coanda and Newton's third - that's laminar. Right? Wrong? Dunno.
Excellent discussion at: http://www.av8n.com/how/htm/airfoils.html#sec-airfoils-summary
Kirk
Grantland
Grantland
> On Monday, 30 June 2014 18:13:10 UTC+2, kirk....@gmail.com strontinnitio:
> > On Monday, June 30, 2014 9:42:53 AM UTC-5, Grantland wrote:
>
>
> Interesting - I'll read more carefully later. So here's a thought: hypothetical 100% laminar flow - you push the air cleanly down. You impart momentum. So isn't Newtons third the cause for lift and circulation just something that happens?
Grantland
>
> Hey I just went to the beginning of the article and that's just exactly what it says.
Grantland
> >
>
> > Hey I just went to the beginning of the article and that's just exactly what it says.
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> Hullo, under Bernoulli, he states that there are no incompressible fluids.
Jim Wilkins
news:e9ec9782-5e7d-4d22...@googlegroups.com...
http://www.allstar.fiu.edu/aero/airflylvl3.htm
"Parasitic drag, which dominates at cruise, of a Boeing 747 wing is
only equivalent to that of a 1/2-inch cable of the same length."
-jsw
Grantland
startled expressions, and the thousand dripping whiskers, and the thousand brisk expostulations, and the thousand soft and o so very necessary elucidations and the thousand humble explanations all add up to one.
- less a ripple of eyelash and a gentle shaving of ivory.
Grantland
Eunometic
However these laminar flow wings also were far less effected by compressibility near the speed of sound. It is for this reason that the P-51 and Tempest V had such good speed not laminar flow. Another advantage is that these wings are relatively thick and so can be made stiff and strong as well as carry large amounts of fuel.
The Germans were aware of them, all their own work, and in fact that Me 309 had laminar flow wings, it flew in June 1942 before the Germans could have seen a P-51A but there were some minor problems and they expected to get the Me 262 into production by then anyway so they gave up on this aircraft. The Fw 190D13/R25 was expected to do 488mph with the Jump 213EB engine so they could have gotten by without it.
The Japanese had a few laminar flow aircraft in service. I think Violet Lightning, Late models of the Betty Bomber and the Mitsubishi Raiden.
Modern wings made of fibre glass reinforced plastic can be true laminar but usually need cleaning systems such as wipers or secretion of detergents.
Grantland
Grantland
Jeff Crowell
> I wonder if anyone's ever tried a rim on the leading edge,
> like those bulbs on ships.
beginning of the wing surface.
Jeff
--
The faster you finish the fight, the less shot you will get.
Murphy's Law of Gunfights
Grantland
> Grantland wrote:
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> > I wonder if anyone's ever tried a rim on the leading edge,
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> > like those bulbs on ships.
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> That would induce flow separation and drag rise at the very
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> beginning of the wing surface.
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> Jeff
Eunometic
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> Hum. So positive pressure is needed for laminar flow, and it gets turbulent on the down slope, where the pressure is low. So you have less turbulence when you make the up slope longer, and hence less drag. Plus the lower compressibity on the sharper leading edge at higher speed.
If you looked at the Mustang Wing Profile it would look like that of one of the fastest fish in the sea, the tuna, viewed from the top. Man/Science imitating nature.
It even has the little fish tail for 'pressure recovery' which helps a little as well. The book "A History of Aerodynamics" by Anderson is a great read on both history. It was mathematically designed by an NACA engineer called Eastman Jacobs.
Grantland
Walt BJ
I flew two aircraft where ground effect was quite noticeable; the T33 and the late model Case XX F102A with the cambered leading edge. The early T-bird with less thrust had a built-in hot day trap; suck up the gear and flaps and pull back on the stick too much and she'd come up out of ground effect, added drag would take over, and she'd settle back down, drag the tail, and come to a screeching stop, hopefully still on the runway. We learned from others' experiences not to be so eager to start a climb.
The Deuce felt like it was landing on a cushion as that 15 degree AOA attitude trapped air under the wings during the last couple of feet before touchdown. Of course there was a mighty downflow over the wings, too, that got straightened out by the runway's proximity to the trailing edge because of the tilt. There was a faintly noticeable change in stick position - forward - to maintain the proper landing AOA (pitot boom tip on horizon). Never noticed any ground effect on takeoff but then we always used the afterburner.
Walt BJ