It's official...

[Kurfürst]

Originally posted by Guppy35
Safe to say the advantages outweighed the disadvantages?  Seems like it when you consider the XIIs all went clipped, and the XVIs did as well and that was in 44-45.]

Outweighted? What you say shows the complete opposite, if we realize that only two, relatively low production variants had them clipped as standard : the MKXII, of which only a mere 100 were built,equipping 2 Sqns and the XVI, that equipped, err, a whole FIVE squadrons in the 2nd TAF.

We are talking about a 100 or so Spitfires with clipped wings out of a THOUSEND or two  that retained the normal wings, because it just wasn't competitive, what they found that clipping the wings helps the poor aircraft but not much the good ones, while the strenghts of the Spitfire, turning and climbing was compromised.

[Wilbus]

In AH the cXVI rolls pretty much the same as the 190 A's at most speeds. Another interesting thing is that either there is way less stick forces for the XVI then the 190 or the pilot in the spit is modelled stronger.

The stick in the plane reacts fast and moves quicker then that in the 190 (or any other plane).

[Kev367th]

In reality there were 1054 Mk XVI's built, ALL with clipped wings, so with the XII that only slighlty exceeds your '100' or so.
Note were talking BUILT/PRODUCED here. Guess they just left them clipped for chits and giggles?

Many many more from the V onwards had clipped wingtips fitted.
Problem is no definate numbers will ever be know because Spits were fitted with all three wingtip types as and when the need arose.

A loss of 160-200fpm climb, but still retaining a turning circle still inside a 190, is not a big deal for an aircraft designed to fight at low alts.
Before you point to the report posted above -
a) Both the 2 Mk V's and the Mk IX are F series Spits NOT LF.
b) The climb rate of the LF IX and LF XVI (even clipped) at low alts is far superior to the F IX.
c) They still out turned a 190
d) Had better roll

Quite frankly looking at the report I still say the guy summing it up TOTALLY lost the plot.

It's like using an F IX or F V with extended wingtips at medium alts to show why an HF VII shouldn't have them.

So as usual Kurfy you are comparing apples to oranges, much the same as the report.
Look at point (ii) Increase in take off run (Only serious for CV operations).
Turned out to be BS, fully laden clipped wing Seafires were trialled off CV's without a take off run problem.

[Crumpp]

That implies that any modification done to fill a need was desperate.

I kind of took it as just that, Guppy.  Not being a "fan" either.  

Think of it like this.  The RAF had nothing in service which would stay with an FW-190 when it rolled out of the attack to extend.  The pilots in the report state that it was "practically impossible" for a clipped wing Spitfire to follow.

This and some other factors tied to design, gave the Focke Wulf pilots the initative in dogfighting.  They could attack and break off when they wanted too at any altitude they were faster.

Just like the Spitfire could stay relatively safe from the FW-190 by reefing his plane into the tightest possible turn, the FW-190 could stay relatively safe while in close with the Spitfire by changing the direction of it's vector of lift.

If one plane could nullify the others "safe" move, well the advantages are obvious.

The normal wing Spitfire had no chance at all of doing this.  The clipped wing Spitfire it was "practically impossible".  That implies a chance.  Not a big one but a chance.  Which is better than nothing.

As to the report, it most certainly covers all clipped wing Spitfires.  I don't think it can be discounted just because it list's some less than outstanding characteristics fans do not like to read.  Nothing in it says clipped wing spitfires were incapable aircraft.  They still outturned an FW-190 though not like a full wing Spitfire and they had at least a chance of following in the roll.


All in all, a pretty good upgrade in Spitfire performance vs FW-190.  It is not a magical upgrade though allowing the aircraft to bend the rules of science.

Where we see an imbalance is in a computer model based off faulty information from a report done 60 years without full intelligence or knowledge of the enemy design.

I think we've agreed in the past that the wartime development of the 190 and Spit parallelled each other with each taking steps up the ladder towards the far end of piston engined fighter development, and I think you'd agree when all was said and done they kept pace with each taking the lead on occasion with the other catching up or passing it again.

I do agree Guppy.  Nobody is saying either plane dominated the other.  They had design strengths and weaknesses.

All the best,

Crumpp

[Kurfürst]

These are two different reports, one is summarizing the pilot's frontline experience, the other is a the conclusions of flight tests done by RAE. In other words, objective and subjective ones, but stating the same. These reports are also very clear and in agreement that the real 'improvement' from clipping the wings is only noticable on planes that have poor sets of ailerons, and perform poorly, which becomes significantly better when the wings are clipped, but there's little difference with 'good' planes in roll when clipped/unclipped.

It was probably a nice, but not very significant improvement of roll rate for the loss of other qualities, which makes me believe that's why it was only smaller number of Spits were built this way as standard (up to the end of 1944 given how late the XVI entered service, I guess that means a few hundred planes produced and less seeing service at most), and most of them retaining their normal wings.

If it would be a huge improment in roll rate vs. relatively small loss of Roc, then I guess it would have been serialized on ALL planes.

[Widewing]

Originally posted by Squire
Had some time to kill, so took Spit XVI up with 100 gas clean, got 404 at +18 lbs at 19,900 ft, which I beleive is FTH (above that the boost drops off). Achieved without aid of a dive.

Just for info...

When the last update came online, I tested the Spit VIII and the Spit XVI for general performance.

Your speed number is spot on.

MK. VIII
Speed @ sea level: 337 mph
Speed @ 22,000 ft: 402 mph
Acceleration, time from 200 to 300 mph at SL: 33.66 seconds
Climb from SL to 10K, starting at 300 mph: 1:44.72

Mk. XVI
Speed @ sea level: 343 mph
Speed @ 20,000 ft: 405 mph
Acceleration, time from 200 to 300 mph at SL: 30.88 seconds
Climb from SL to 10K, starting at 300 mph: 1:38.38

Mk. XIV
Speed @ sea level: 359 mph
Speed @ 27,000 ft: 445 mph
Acceleration, time from 200 to 300 mph at SL: 28.56 seconds
Climb from SL to 10K, starting at 300 mph: 1:44.69

Limited testing of the new 109s produced the following.

109G-14
Speed @ sea level: 347 mph
Climb from SL to 10K, starting at 300 mph: 1:45.72

109K-4
Speed @ sea level: 367 mph
Climb from SL to 10K, starting at 300 mph: 1:43.19

109G-6
Speed @ sea level: 337 mph
Climb from SL to 10K, starting at 300 mph: 1:53.79

Other revised Spitfires, limited testing.

Mk. IX
Speed @ sea level: 319 mph
Climb from SL to 10K, starting at 300 mph: 2:05.94

Mk. Vb
Speed @ sea level: 305 mph
Climb from SL to 10K, starting at 300 mph: 2:26.04

Seafire Mk. IIc
Speed @ sea level: 304 mph
Climb from SL to 10K, starting at 300 mph: 2:33.21

Other recently added or revised aircraft.

P-38G
Speed @ sea level: 327 mph
Speed @ 25,000 ft: 401 mph
Acceleration, time from 200 to 300 mph at SL: 45.03 seconds
Climb from SL to 10K, starting at 300 mph: 2:27.59

P-38J
Speed @ sea level: 344 mph
Speed @ 25,000 ft: 419 mph
Acceleration, time from 200 to 300 mph at SL: 36.53 seconds
Climb from SL to 10K, starting at 300 mph: 2:03.55

P-51D
Speed @ sea level: 367 mph
Speed @ 25,000 ft: 441 mph
Acceleration, time from 200 to 300 mph at SL: 35.32 seconds
Climb from SL to 10K, starting at 300 mph: 2:12.03

Fw 190D-9
Speed @ sea level: 375 mph (367 mph w/bomb rack)
Speed @ 20,000 ft: 426 mph (419 mph w/bomb rack)
Acceleration, time from 200 to 300 mph at SL: 30.83 seconds
Climb from SL to 10K, starting at 300 mph: 2:04.35

I've always had an issue with P-38 acceleration in Aces High. Pilots who flew both the P-38 and the P-51 universally agree that the P-38 was a "drag racer" in comparison, and the power loading of the P-38 seems to support that opinion. At normal weights in the RW, the P-38J uses little less than 65% of the runway distance to get airborne when compared to a P-51D.

My regards,

Widewing

[Kev367th]

The only reason I am saying I don't put much stock in the report is the aircraft they tested with clipped wings.

Vb and IX - Both F versions, where ceiling is important.

Going through the disadvantages listed in the report -

(i) Inability to turn as fast - True, but still turned inside a 190

(ii) Take off run - A disadvantage? Were the RAF operating out of backyards? As for CV ops, see previous post, wasn't a problem.

(iii) Loss in rate of climb - Consider that a clipped wing Merlin 66 Spit climbs better at it best alts than the F IX or F V's in the report.

(iv) Lowering of service ceiling - Yup a problem for an F series Spit, not a problem for an LF series designed for lower alts anyway.

(v) Decrease in speed over 20k - As above, yup a problem for F series, but resulted in an increase in speed at lower alts, again where the LF series was designed for.

In it's context comparing it to F series Spits it's valid, however it's not valid against the Merlin 66 LF series Spits.

Like I said its the equivalent of taking F IX, F V fitting them with extended wingtips and using that as a basis for why they shouldn't be fitted to the HF series Spits.
 
Much the same as certain people using a VIII with extended wings to prove a standard wing VIII rolls/turns badly.

I'll leave the XII to Dan, they were Griffon birds.

Widewing - Data appreciated.
How much fuel in the VIII, 100%?
If so you would need to burn off some fuel to get it the same as the XVI. Then you would find the VIII is a lot closer if not better in some categories than the XVI.

[Kurfürst]

Interesting, some data seems off :

Originally posted by Widewing

MK. VIII
Speed @ sea level: 337 mph ...aboutOK
Speed @ 22,000 ft: 402 mph .... - 2mph
Acceleration, time from 200 to 300 mph at SL: 33.66 seconds
Climb from SL to 10K, starting at 300 mph: 1:44.72

Mk. XVI
Speed @ sea level: 343 mph... too fast, +7mph (+18lbs)
Speed @ 20,000 ft: 405 mph... +1 mph


Limited testing of the new 109s produced the following.

109G-14
Speed @ sea level: 347 mph... to slow, -6mph
Note : The G-14 was also reported 10mph too slow at rated altitude.

109K-4
Speed @ sea level: 367 mph... about OK, should be 369mph (for 1.8ata)
Climb from SL to 10K, starting at 300 mph: 1:43.19

109G-6
Speed @ sea level: 337 mph.. too fast, should be 329mph, by +8mph
Climb from SL to 10K, starting at 300 mph: 1:53.79

Other revised Spitfires, limited testing.

Mk. IX
Speed @ sea level: 319 mph.... way too fast, by +9mph (for +15 lbs)
Climb from SL to 10K, starting at 300 mph: 2:05.94
[/B]

From the above, if there's issues with the XVI performance, it's quite understandable why it's so highly rated in low altitude combat. It's slightly faster at low alt than it should be, and it's opponent G-14 is slightly slower than i should be.

Historically, the XVI was good for about 337 mph at SL, the G-14 for 353mph. There was 13mph difference between them.But in AH, the XVI does 343, the G-14 only 347, so the diffo is only 4 mphg actually.

Another pair that is mutually overmodelled is the Merlin 61 FIX and the G-6, both faster by 8-9mph at SL than they should be in absolute terms, even though they are relative to each other OK in speed.


....

I've always had an issue with P-38 acceleration in Aces High. Pilots who flew both the P-38 and the P-51 universally agree that the P-38 was a "drag racer" in comparison, and the power loading of the P-38 seems to support that opinion. At normal weights in the RW, the P-38J uses little less than 65% of the runway distance to get airborne when compared to a P-51D.

My regards,

Widewing [/B]

From what I have seen the P-51D Cd0 was around 0.0170, the P-38J's - 0.0270 Add the fact that the P-38 had much higher wing area with what you have to multiply the Cd0, and there's absolutely NO WAY the P-38 could be claimed a 'drag racer', esp. compared to the Mustang. Powerloading, dunno, the P-38 has about twice the weight, and twice as many similiarly powerful engines, so it could cancel it out.

[Crumpp]

The only reason I am saying I don't put much stock in the report is the aircraft they tested with clipped wings.

That's true and you are entitled to your opinion.  I would certainly agree with you if this was the Luftwaffe testing an RAF design.  This however, is the end user testing their own equipment.  Different animal entirely whose conclusions are much harder to discount on a whim.  Keep in mind the report was requested by the Royal Air Force to help win the air war.

 They came to a different conclusion with a lot more pertinent facts at their disposal than anyone on these boards.

That is backed up by the fact only certain Spitfires were produced with clipped wings.  Certainly not the majority of Spitfires produced had clipped wings.

Looks to me like the optimism of the proponents of the clipped wing Spitfire found their inspiration from the data contained in RAE 1231.  On paper the Clipped Spitfire should have been equal and even superior to the FW-190's roll depending on the speed.

That simply did not carry over into combat, as RAE 1231 was not the correct roll capability of the FW-190.

All the best,

Crumpp

[Kev367th]

Spit XVI sea level - As its performance is comparable to a LF IX and a normal span LF IX could hit 336mph at SL.

Then a clipped wing Spit would be faster, clipping wings gave a speed increase at low alts, maybe even the 7mph your stating.
Yet again your mixing your wing types where performance is conscerned.

RE: The report - Looking at the top of the pilot comments, all were flying the F Vb, so yes in that context it may be considered undesirable.
However I would suggest in the case of low alt Merlin 66 equipped Spit, the same is not true.

[Crumpp]

Mk. XVI
Speed @ sea level: 343 mph... too fast, +7mph (+18lbs)
Speed @ 20,000 ft: 405 mph... +1 mph

Looks to me like it is within Supermarines published limits.  It is just on the upper end of the percentages and optimistic.

Didn't all Mk XVI's come with clipped wings?  I would think Supermarine would factor that in.

All the best,

Crumpp

[Kev367th]

No Crump that data is for a NORMAL SPAN LF IX, not a clipped wing LF IX/XVI.

XVI
Should be 336mph at sea level + increase for clipped wings.
Rate of climb sea level would be 4620 - loss 160-200fpm for clipped wings. (not the 3700fpm or so that was suggested earlier in this thread)

VIII
I would suggest that the VIII is actually underperforming quite badly, it's performance figures are closer to extended wing VIII than a normal span VIII.

[Nashwan]

Mk. XVI
Speed @ sea level: 343 mph... too fast, +7mph (+18lbs)
Speed @ 20,000 ft: 405 mph... +1 mph

Spitfires were tested with mirrors, the AH Spitfires don't have them. Removing the mirror accounted for about 6 mph.

[Crumpp]

No Crump that data is for a NORMAL SPAN LF IX (same performance as a LF XVI), not a clipped wing LF IX/XVI.

No I meant what I wrote Kev, the data is optimistic.  However you want to slip the curve due to wings, facts remain it is based on optimistic data.

BS539

The two remaining gun stubs were fitted with hemispherical blanks. All gun ports were sealed, but the ejection chutes beneath the wings relevant to the guns fitted were open.

http://www.spitfireperformance.com/bs543.html

JL165

Except for these modifications, the engine was a standard production Merlin 66, the aircraft being a normal Spitfire IX, with 10'9" diameter Hydulignum propeller and standard tropical type of air intake, operating as temperate. The aircraft was flown at a weight of 7,234 lbs. (84 galls. total fuel capacity).

There is a 9mph difference in the speeds.  Both aircraft are within normal specs.  It is just that BS539 represents the far end of the scale while JL 165 is a normal finish standard production without special attention to improve performance.

Before you even bring up the tropical filter, they were standard on all spitfires and this one was opened to temperate conditions.  Just like Europe not Africa.

Now let me pause and spell out my position.  I support either data set.  Both are realistic and obtainable by the design.  Arguing over a few mph is frankly just stupid.

What I do not support is data that is so far to one side of the other that the historical balance of the game shifts.  The Spitfire MkXVI was not the wondercraft it is showing itself to be in AH in the real world.  

If it was, I doubt any other variant would have been developed.

All the best,

Crumpp

[Crumpp]

Spitfires were tested with mirrors, the AH Spitfires don't have them. Removing the mirror accounted for about 6 mph.

When are they going to model FW-190's with the Kommandgerät boost overridden to 1.8ata cause the crewchief drills out the jets?

How about when FW-190 crews put the supercharger out of limits contrary to regulations?

I can give them the reports on those Geschwader level mods that have the Focke Wulf  190A screaming along at 595kph on the deck in 1943.  Is it representative of a frontline FW-190 fighter.  Sure, in some of the Stafflen.  Is it average, not a chance.  

Can we get summer/winter fuel so our aircraft are faster all year long?  Summer fuel with attenuating ring gave some pretty good gains.

How about just getting the right corrections for the data used?

Most importantly:

Did Spitfires come from the factory with mirrors?

This is exactly why things are out of whack in AH world.  Whose modification can make it into the game as substitute for standard.

All the best,

Crumpp