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View Full Version : Nice 'Spitfire, the legend, the facts and its Opponents' Film, not seen before..



Xiolablu3
03-11-2008, 03:56 AM
http://www.youtube.com/watch?v=3ZljRxXsBpc&feature=related

Nothing we really dont know, but it compares the ME109 and Spitfire cockpits, engines and manufacturing quality and is very interesting to watch...

In particular interest is the manufacturing problems which came with the SPitfire. The Me109 could be made in 1/3 the time as the later marks. The Bf109 was made with manufacturing in mind, and was simple to produce, it made concessions in aerodynamics to make it easier to build.

Yet, the Spitfire was designed by Mitchell with absolutely nothing else in mind but aerodynamics, with no concessions to manufacturing, and presented real problems to build in the early days.

Good Info about the Bf109 vs the Spitfire and FW190 vs Spitfire, in part 4 a RAF veteran talks about the troubles the FW190 posed in 1942 for the RAF pilots up until the MkIX Spitfire...

http://www.youtube.com/watch?v=vihSJOBN1zE&feature=related

Schwarz.13
03-11-2008, 04:14 AM
Nice one Xialoblu3 - i'll watch that later http://forums.ubi.com/images/smilies/25.gif

JG14_Josf
03-11-2008, 07:05 AM
X3,

Is that legend or myth concerning the aerodynamic elliptical design feature of the Spitfire wing? I ask because I've read and can link where I've read how the Spitfire wing was designed with wing twist for handling and in doing that the net effect is to cancel out the aerodynamic feature of an elliptical shape.

Here is the link (http://en.wikipedia.org/wiki/Elliptical_wing)


An elliptical wing is a wing planform shape, first seen on aircraft in the 1930s, which minimizes induced drag. Elliptical taper shortens the chord near the wingtips in such a way that all parts of the wing experience equivalent downwash, and lift at the wing tips is essentially zero, improving aerodynamic efficiency due to a greater Oswald efficiency number in the induced drag equation.

The elliptical wing has seen only limited use, mainly because :

- the compound curves involved are difficult and costly to manufacture,
- the pure elliptical shape as an ideal planform may be a myth. A truncated ellipse, same span, same area, has the same induced drag. Trapeze planforms with 0.4 or 0.5 taper ratio are induced drag equivalent, too.
- furthermore, the wing's uniform lift distribution causes the entire span of the wing to stall simultaneously, potentially causing loss of control with little warning. To compensate, aircraft such as the Supermarine Spitfire used a modified elliptical wing with washout, though such compromises increase induced drag and reduce a wing's efficiency. Note, though, that the typical tapered wing planform has to employ more washout than the elliptical planform wing to see similar stall performance, which puts the tapered wing at a disadvantage.

The YouTube link on the Spitfire versus its opponents has one guy saying:

"They were elliptical to get the best aerodynamic results."

Designing, if I have this right, elliptical shape is a feature that lowers induced drag at the cost of handling where a low induced drag wing (by elliptical shape design) will handle poorly "potentially causing loss of control with little warning" and so the Spitfire was designed with washout or wing twist "which increases induced drag and reduces a wing's efficiency".

I thought it would be a good idea to point that out if someone watching the YouTube link were to be inspired by it to perpetuate a myth like this:

"They were elliptical to get the best aerodynamic results."

Myths are usually half truths; it seems. The other half being the washout and this is a familiar thing to note. Another example of a half truth type myth is the P-51 laminar flow aerodynamic efficiency. The half true part is the design feature. The other half of the story concerns the actual manufactured results of that aerodynamic design where laminar flow was spoiled by irregularities in production examples.

The YouTube link is a very good find. Thanks.

Xiolablu3
03-11-2008, 09:16 AM
I dont know to be honest Josf, you probably know more about the eliptical wing and its benefits/drawbacks than I do, I am no expert on aerodynamics.

Maybe some of the other guys, who know more about this subject, can tell us more.

I have heard that it was thought AT THAT TIME (may be different now) that the eliptical wing at that time was the most efficient type of wing with regards to lift/speed/handling, but it was difficult to produce, it states in the program that the wing was the hardest part to produce.

I do know that the SPitfire, according to most of todays Warbird pilots, is supposed to have the nicest handling of all the 'thoroughbred' WW2 fighters, but whether thats to do with the massive wing area or the elliptical wing, I am not sure. I know they had to put in 'washout' to give warning of the stall which added to its easy handling.

Aaron_GT
03-11-2008, 09:23 AM
The Spitfire (as the Spiteful) reverted to a trapezoidal planform, with laminar flow, for the Spiteful. Much improved level speed on the Spitfire XIV chassis by about 50 mph.

I say reverted as the previous Mitchell design with fixed undercarriage was trapezoidal, as were the very first designs immediately before the classic Spitfire planform.

Xiolablu3
03-11-2008, 12:55 PM
The Spiteful was only really an experiment however, I think. 'Hey lets try a Spitfire with a Laminar flow wing' sort of idea.

It wasnt made in great numbers, and wasnt very well liked if I recall correctly. It had very poor handling compared to a Spitfire

I gather it was more as a complement to 'proper' Spitfires' than a full fighter in itself.

Mercanario
03-11-2008, 06:55 PM
Cool, i remember watching this years ago on Channel 4 UK..thanks for the link!

VW-IceFire
03-11-2008, 07:09 PM
I think the famous quote from Mitchell about the wings was that he didn't care (I'm paraphrasing here) what shape the wings were so long as the guns all fit inside the wing. I guess the elliptical setup was the best for what he wanted in terms of aerodynamics but also in terms of armament. Of course that didn't last long as they really needed cannons and those weren't exactly short.

The Tempest also seems to have done well with semi-elliptical wings...the joke being that the Air Ministry wouldn't accept a fighter that didn't look like a Spitfire http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

mynameisroland
03-11-2008, 08:14 PM
Ice I have plans for the Tempest and in its Mk I form it had the option of full unclipped eliptical wings. Hawker probably showed these to the air ministry before lopping the tips off.

M_Gunz
03-11-2008, 09:48 PM
Originally posted by JG14_Josf:
Myths are usually half truths; it seems.

Especially when you give full voice to any opinion that says otherwise.
I'm sure there will be a complete manifesto proving it all to be true without any actual data
taken from any actual Spitfire.

JG14_Josf
03-11-2008, 10:53 PM
Anyone,

It things go according to custom the personal attack by M_Gunz will be ignored while I am blamed for causing trouble. The moderators will warn everyone while singling me out as the cause of the problem.

In fact the information on the trade-off between easy handling and aerodynamic efficiency is published by people other than me. I read it. I link it.

Ignoring things may temporarily remove things from sight. Perhaps that is like ignoring the need to make an airplane as small as possible to minimize displacement. I can't say.

I am not the expert, not the no it all, nor am I trolling. Some people have an interest in finding and knowing things that are accurate. I share that desire.

Please consider noticing how things work on this forum. Trolls control it. This is the price of admission.

ImpStarDuece
03-11-2008, 11:02 PM
Originally posted by Aaron_GT:
The Spitfire (as the Spiteful) reverted to a trapezoidal planform, with laminar flow, for the Spiteful. Much improved level speed on the Spitfire XIV chassis by about 50 mph.

I say reverted as the previous Mitchell design with fixed undercarriage was trapezoidal, as were the very first designs immediately before the classic Spitfire planform.

Couple of points.

The major production (really only production) model of the Spiteful was Mk 14, which topped out at about 476 mph. This is compared to the 448 mph of the MK XIV. So, not 50mph faster, but about 28 mph faster, or a bit less than the performance difference between a Mk IX and a Mk V.

The 494 mph Spiteful was the Mk 16, only two of which were made, both of which were conversions from Spiteful Mk 14s, with three stage, two speed Griffons.

When a laminar flow wing was fitted to a Spitfire Mk XIV as a test bed, the absolute speed improvement was only modest, about 5-8 mph, or roughly the same improvement as the Spitfire made from going the Mk XIV to the Mk 21.

From a drag standpoint, what was more important in the Spiteful's improved performance was the reprofiling of the wing radiators and air intakes and carburettor intake.

The other key to the Spiteful's improved performance was the more powerful Griffon engine. The Mk 14 had a 2,375 hp Griffon engine, compared to the 2,035 hp Griffon in the MK XIV/21.

The Mk Spiteful Mk 16 had a 2,420 hp three stage, two speed engine, so it had even more power to play with. Stick one of these on a Spitfire Mk XIV, and see how much faster it would travel.

The switch to the laminar flow wing was driven by concerns about the high transonic drag limitations of conventional wings. However, later research on the Supermarine Attacker concluded that the original Spitfire wing performed better at high transonic speeds than the laminar flow wing fitted to the Attacker.

BTW, post war research indicates that one of the worst points of the Spitfire from a drag standpoint was the angle of the windscreen, and its interface with the fuselage, which was too steep and created a suction effect, resulting in turbulent airflow over the fuselage. Some drag calculations estimate that it robbed the aircraft of approximately 5 mph in top speed.

Gumtree
03-12-2008, 04:53 PM
Nice find,
I find it interesting to hear Laddie Lucas talk about the caning that the 190's gave the MkV's when that plane was introduced, yet rather fascinated to hear what he says about the shift in superiority when the MkIX appears.

Not trying to have a lend or anything but it is just like a Moto Gp or car racer speaking on the challenges of a race and comparing equipment. It really brings to light the constant shift in the balance of performance as machinery and its ability swung back and forth.

The comparisons of the cockpit is nothing I have not read before, yet is is fascinating to hear and see a comparison from a pilot whilst sitting in both.

Schwarz.13
03-12-2008, 05:21 PM
Did anyone notice the narrator 'clearing his throat' at 3:15 in part 2 - was he perhaps resisting the urge to laugh or make a double entendre? http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

Schwarz.13
03-13-2008, 09:06 PM
Actually, in all seriousness - when the RAF pilot gets into the 109 cockpit to evaluate it (after the Spit cockpit) i was quite shocked at just how cramped and claustrophobic it seemed!

Yes i had read many times that the 109 cockpit was very cramped, but seeing that guy in it (and he was very slim, albeit tall) really slammed home the fact that it must've been extremely unpleasant to go to war in one of these (at least until the Erla canopy), and rearward visibility, despite weaving/kicking rudder etc. must've been very bad!

BTW - part 5 of 5 seems to be from a different programme altogether...

luftluuver
03-13-2008, 11:02 PM
Originally posted by Schwarz.13:
Actually, in all seriousness - when the RAF pilot gets into the 109 cockpit to evaluate it (after the Spit cockpit) i was quite shocked at just how cramped and claustrophobic it seemed!
Didn't watch the vid but saw on another that when Hans-Ekkehard Bob**, a LW ace, climbed into a Spit cockpit he commented on how roomy it felt compared to the 109.

**
Hans Ekkehard Bob (24 January 1917) was a German Fighter pilot, serving with the Luftwaffe. During World War II, Bob flew approximately seven hundred combat Missions, and claimed sixty victories; thirty-seven of which were on the eastern front.

Rank: Major
Units:
JG 54
JG 51
JG 3
EJG 2
JV 44
Commands: IV./JG 51, II./JG 3, II./EJG 2
http://en.wikipedia.org/wiki/Hans_Ekkehard_Bob

Kurfurst__
03-14-2008, 03:40 AM
Scale dimensions of the two cocpits

http://i38.photobucket.com/albums/e133/Kurfurst/109e_Spit_cpit_xsection.png

And canopy

http://i38.photobucket.com/albums/e133/Kurfurst/109e_Spit_cpit_malcolm.png

The blue outlines are the Spit, the Red lines are the 109. The Spit is with the bulged/blown Malcolm hood, which had a bubble for the pilot, this was introduced at around mid-war to the Spits. Earlier Spit canopies were narrower; the outlines of the early canopy can be seen in the cross section (thick blue lines).

One thing to consider that when he sat in the Spitfire cocpit he closed neither the canopy, nor the side entry 'door', as in the 109G.

The main difference between the Spit and 109 cocpit seating was the sitting position of the pilot. In the Spit, he sat upright like in an armchair, while in the 109 (and 190) the seat was inclined and the pilot sat with legs high and well in front of him, like in F-1 race car. While the latter position would certainly feel less natural and more cramped with your knees so high, it meant that pilot would resist high G forces much better during combat manouvers, and would black out later.

luftluuver
03-14-2008, 05:40 AM
<span class="ev_code_YELLOW">A canopy is not a cockpit.</span> http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif

JG14_Josf
03-14-2008, 07:12 AM
Thanks to X3, again, for finding and linking the video. It was well worth watching. Commenting on it for discussion purposes is interesting to me too. Even the condom part was entertaining.

I've read something concerning fighter piloting that may lend itself to this cramped cockpit perspective and the ability to maneuver inside the plane as well as maneuver the plane through the air. Fighter pilots, like F1 drivers, were athletes. Perhaps a day in the not too distant future will offer the serious fighter sim player a work out while playing.

Imagine having a scale made cockpit where the player is able to simulate the confines of the cockpit including all the physical limitations of stick force, stick movement, and perspective movement.

Just how hard was it to look back while rolling into a high g spiral zoom climb?

The player may not have entertained the possibilities. Certainly a well trained athlete who flew up to 5 hour long missions a day in combat for a full year would be able to find the edges of the envelope better than an overweight old man sitting behind a desk in the suburbs of California.

The game player merely moves a hat switch or now moves a sensor on a hat. The fighter pilot has to actually do the work. Some day the game industry may level the gaming field. Serious gamers, in the future, may go full switch for real. Imagine a physical limitation requiring, at least, an arm and a knee pushing the forced feedback stick one way while the head-set requires the player to twist and stretch all the way back and around the edges of the armor plate. Which eye is dominant? Looking back left while rotating the head left may allow the right eye to get that much more vision back before the head bonks the canopy.

I don't know about some players but this player really appreciated the leap from the old games to IL2 as the perspective looking back was greeted with a moving rudder seen, and moving elevator surface.

How many players look back under g load near blackout? If your head weighs 100 pounds can it still be done?

Did anyone else notice the comments, in the video, concerning the craftsmanship of the manufactured aircraft?

Schwarz.13
03-14-2008, 07:47 AM
Originally posted by JG14_Josf:
Certainly a well trained athlete who flew up to 5 hour long missions a day in combat for a full year would be able to find the edges of the envelope better than an overweight old man sitting behind a desk in the suburbs of California.


Yes, but that is assuming he survived his first combats!

Consider the green pilot getting stuck in a furball in his tiny cramped cockpit, and who has not yet learned how to watch his 6 effectively with his very limited view.

I'd imagine getting trapped whilst trying to bail-out was an all-too-common occurence too...


Originally posted by luftluuver:
<span class="ev_code_YELLOW">A canopy is not a cockpit.</span> http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif

I agree. But to be fair to Kurfurst - the pilot in the video did NOT close either the Spit canopy or side door (as Kurfurst pointed out) to give us a feel of what it was like to be shut inside that cockpit...

JG14_Josf
03-14-2008, 10:38 AM
Consider the green pilot getting stuck in a furball in his tiny cramped cockpit, and who has not yet learned how to watch his 6 effectively with his very limited view.

OK it is considered,

How about considering a green pilot getting stuck in a furball in his large and roomy cockpit?

I had the pleasure of hearing Gabby Gabreski speak during a Warbirds (game) convention. He spoke of being a green pilot while flying his P-47. He was very entertaining about it. He said something about a plan to run the varsity' guy, in a 109, behind him out of ammo'.

Certainly the cramped cockpits required a lot more work to gain situational awareness. I don't think that is the same thing as saying a cramped cockpit eliminates situational awareness. Put another way; I don't think a roomy cockpit automatically creates situational awareness.

One very likely reason for confining the dimensions of a cockpit is the aerodynamic consideration. Having a huge engine of great capacity to produce power may relieve some of the requirements of reducing aerodynamic size. The box covering the engine must be shaped with air resistance in mind. The box must also cover the pilot.

How much air resistance was caused by the blown canopy with the shallow angled windscreen compared to, say, the steeper glass front and low hood rapped around the pilot's head version?

The bigger planes with the larger engines could afford more room perhaps.

The green pilots may have gained something with an increase in cockpit room in time.

A blind spot remains a blind spot even if it is small. If the fighter pilot had a choice, it seems, the choice would be for a smaller blind spot. If the fighter pilot had a choice, it may be a preference for the room needed to move the stick as needed when needed.

When the pilot has spent enough time in a cramped cockpit, or a roomy one, my guess is that the limits become familiar and less claustrophobic maybe.

Bremspropeller
03-14-2008, 01:35 PM
The Spit offers more shoulder-space.
As well, the head-room is wider - an important aspect for looking at your six.

deepo_HP
03-14-2008, 04:18 PM
well, i was myself a bit wondering, if there was such a difference between both cockpits...

the views from front didn't show a spitfire, which looked much more comfortable.
109:
http://www.dadatainment.info/wb/109_3.jpg

spit:
http://www.dadatainment.info/wb/spit_2.jpg

and although the camera-angles were different, i hardly saw a 25% tighter cockpit for the
109:
http://www.dadatainment.info/wb/109_1.jpg

compared to the
spit:
http://www.dadatainment.info/wb/spit_1.jpg