Bf-109 vs Spitfire vs Fw-190 vs P-51

[Kurfürst]

Price went on to observe that relatively small deteriorations in the airframe could reduce the performance of a Spitfire in the same way that the RAE experiment increased its performance...

Actually the RAE report you are referring to investigates the drop in performance of Mark Vs due to poor production quality; the RAE report investigates how much of this was attritubable to a, Poor production/finish quality b,Due to introduction of new (and draggy) new equipment to the basic design. In other words it more appropriate to speak of restoring the performance.

Looking at the captured Spitfire VB with DB605 - I wonder how well the airframe was looked after at Rechlin?

If the curves for the Merlin 45 Spitfire are coming from Rechlin's trials with the captured Spitfire V (which are pretty much in line with the nominal British specification for the type), I'd say they did quite well, or at least got themselves a better than average Mark V, as the RAE report you refer to above notes:

 

[NZTyphoon]

There is always some variation but each engine (at least in the west) was placed on a test stand and run for several hours before shipment from the factory. During this time the engine was connected to a load and power measurements were taken. Any engine not meeting specifications (plus or minus so many percent or a minimum HP ) would be rejected for refitting/repair.
That being said there were variations in service. Rings and valves could wear, linkage adjustments could move a bit, Condition of sparkplugs, etc.
Some times an engine that seemed to work fine at sea level was well down on power at altitude. Air is an insulator and in the thinner air at high altitudes some magnetos and wiring harnesses shorted out or cross fired.

From memory the USAAF had a deal of trouble with the magnetoes of its P-47s at altitude over Europe until pressurised units were introduced.

Waaay O.T but it is interesting to note that Nissan builds each engine, gearbox and differential of each GT-R as a unit in a special dust-free environment; because the engine, gearbox and differential are matched as a unit any variations from specs are extremely small.

 

[NZTyphoon]

Actually the RAE report you are referring to investigates the drop in performance of Mark Vs due to poor production quality; the RAE report investigates how much of this was attritubable to a, Poor production/finish quality b,Due to introduction of new (and draggy) new equipment to the basic design. In other words it more appropriate to speak of restoring the performance.

Interesting to note that this was recognised and 1) New satin-finish paints were introduced and 2) flush riveting throughout. 3) Production standards were improved. According to Shacklady and Morgan the first two refinements were introduced in late 1942-early 1943, before the Farnborough tests, which helped confirm what was already known.

 

[Kurfürst]

Interesting to note tah this was recognised

Yes. Two years after the problem existed - I do have to wonder what supernatural powers of perception were required to note that Jerry piston engined fighters were something like 100 kph faster at altitude than the Mark V suffering from poor production quality, but it kinda explains the deep curiousity of Air Intelligence reports about puffs of smoke emerging from German fighter exhausts in combat - maybe some secret Nazi black magic involving some exotic chemical addition.. or simply, as was the case, caused by the other guy giving full throttle..! )

1) New satin-finish paints were introduced and
2) flush riveting throughout.

Oh, flush riveting, glad the guys at Supermarine caught up by the 1943 with the newest fashion.
How much was this an 'improvement' for the Spitfire's finish is strongly questionable though. The use of mixed riveting (flush riveting everywhere except for the fuselage) was decided early in the development in Spitfire after empirical tests (I think split peas were used on a scale model to measure the difference).

It was found that using convential dome rivets everywhere would cost 22 mph on the prototype compared to flush rivets; so flush rivets were used everywhere except for the fuselage, which was measured to only decrease speed by 1 (one) mph. It was so insifignicant that using domed rivets on the fuselage was accepted as a (fairly good) compromise.

On the Mark VII/VIII and related airframes the rivets on the fuselage were replaced by flush rivets as well, increasing the top speed by a mighty 1 mph. Grand improvement, indeed.

Do you have information about how much these new paints were supposed to improve finish and performance..?

3) Production standards were improved. According to Shacklady and Morgan the first two refinements were introduced in late 1942-early 1943, before the Farnborough tests, which helped confirm what was already known.

Indeed and that's what the report says, that the new porduction Mark IXs from the summer 1943 (the report and preceeding reports are dated between June 1943 and September 1943) had 'some' improvement in equipment and build quality. Which is grand, expect for the fact that the most commonplace Spitfire for two years actually had the performance below that of the Spitfire I and Bf 109E of 1940, and the Mark Nines were still around in penny pocket numbers...

 

[Glider]

Does anyone know the file number for this report on the performance difficulties of the Spitfire due to poor finish? It looks like an interesting file to look up in full.

 

[RCAFson]

Does anyone know the file number for this report on the performance difficulties of the Spitfire due to poor finish? It looks like an interesting file to look up in full.

The Spit V trop certainly took a hit in performance, and I wonder if this was part of the report?

 

[renrich]

NZT, I believe you are correct about the P47 and the magneto wiring problems and the Corsair had the same problems in the PTO early on. The P47 also had landing gear problems when first deployed, if memory serves.

 

[NZTyphoon]

Does anyone know the file number for this report on the performance difficulties of the Spitfire due to poor finish? It looks like an interesting file to look up in full.

I'm not sure but I have seen the full report somewhere; it is mentioned in Morgan and Shacklady. Possibly Mike Williams will know.

 

[Kurfürst]

Well you can ask nicely for the report instead spouting the conspiracy nonsense...

 

[Glider]

Kurfurst, If you have the full report I would appreciate a copy, or if its easier the full name of the file as held presumably in the National Archives.

 

[The Basket]

I would also like to read the report.

Each Spitfire V would have been test flighted and any weakness flagged up.

Just can't see how a bad machine would have been accepted into service.

The shadow factory at Castle Bromwich was a nightmare in the early days and I can imagine poorly finished machines going out the door.

 

[parsifal]

I am at a loss as to where this debate is headed. I think it is fairly well known that the Spitfire V was somewhat outclassed by its axis contemporaries, but despite this, the exhange rates over england and france throughout 1941 steadily improved, and were only slightly worse than 1:1 towards the end of the year, according to Foreman. It appears the SpitV struggled more aginst the FW 190 than the Me 109f. So if the SpitV was so bad, but still managed a half decent exchange rate, then what was wrong with the axis aircraft types.

Facts are that there was little difference in the qualitative edge by either side at the time of the initial deployment of the Spit V. Later, as the qualitative scales tipped in favour of the allies, the exchange rates began to tip in favour of the allies, but this came much later and in different machines.

 

[NZTyphoon]

I am at a loss as to where this debate is headed. I think it is fairly well known that the Spitfire V was somewhat outclassed by its axis contemporaries, but despite this, the exhange rates over england and france throughout 1941 steadily improved, and were only slightly worse than 1:1 towards the end of the year, according to Foreman. It appears the SpitV struggled more aginst the FW 190 than the Me 109f. So if the SpitV was so bad, but still managed a half decent exchange rate, then what was wrong with the axis aircraft types.

Facts are that there was little difference in the qualitative edge by either side at the time of the initial deployment of the Spit V. Later, as the qualitative scales tipped in favour of the allies, the exchange rates began to tip in favour of the allies, but this came much later and in different machines.

Not forgetting that Spitfire Vs, mostly Tropical with Vokes filters, tipped the balance over Malta against Bf 109Fs and Macchi 202s, amongst other types of fighter, partly because of superior tactics introduced by Park. The horrible old barge could still put up a good fight, in spite of what some people here seem to think. 8)

 

[Kurfürst]

I am at a loss as to where this debate is headed. I think it is fairly well known that the Spitfire V was somewhat outclassed by its axis contemporaries, but despite this, the exhange rates over england and france throughout 1941 steadily improved, and were only slightly worse than 1:1 towards the end of the year, according to Foreman.

... and all it took was to send the entire Fighter Command to France where there were but two Jagdgeschwadern. 8) Though I am not aware how Foreman calculates the exchange rates - fighters vs fighter losses only, or BC's losses are included as well..?

It appears the SpitV struggled more aginst the FW 190 than the Me 109f.

IIRC there was a very enlightening discussion on this at TOCH, and the conclusion was that despite all the post-war literature lamenting on the Fw 190 scourge, the situation in 1941 and 1942 was just as bad if not worse than after the Fw 190 appeared. The Fw 190 certainly brought a shock to FC, but it very much appears it was more of a psychological one, rather than physical: while the 109 was fairly similiar to the Spitfire in its qualities, the 190 was an entirely different, and completely alien beast. So I wonder, how did you manage to arrive at your different conclusion?

So if the SpitV was so bad, but still managed a half decent exchange rate, then what was wrong with the axis aircraft types.

That's a big IF - when and where on Earth did the Mark V manage even half a decent exchange rate? Of course it cannot be blamed on the aircraft alone - after the losses over France and Britain in 1940, FC was short on experienced pilots, the tactics were still in infancy, and these alone were probably more decisive than some extent technical inferiority.

Facts are that there was little difference in the qualitative edge by either side at the time of the initial deployment of the Spit V.

If these are the 'facts', then why the horrible exchange rates, why the severe losses, despite massively outnumbering the fighter defences in France, why the Mark IX, and why RAF reports of the time keep stating that they can't keep up with the opposition, especially at altitude...?

 

[Kurfürst]

I'm not sure but I have seen the full report somewhere; it is mentioned in Morgan and Shacklady. Possibly Mike Williams will know.

Oh, good ole' Mikey has the report, but understandably its not something he wants to advertise too much on Spitfire performance history. Well of course that, the roll rate report on the Spitfires, fully rated Bf 109s in his comparison articles and so on.

Anyway here it is... you see, all you have to do is ask nicely. 8)

 

[Juha]

Hello Kurfürst
a more realistic view on Malta, old message but it seems to be necessary to repeat it:


- Aviation (Aviation - Aircraft of World War II - Warbird Forums)
- - Bf-109F-4 and a bleak time for RAF (http://www.ww2aircraft.net/forum/aviation/bf-109f-4-bleak-time-raf-5979.html)

"Juha 01-08-2007 10:44 PM
On Malta losses

Hello Kurfürst!
Some facts on the last LW effort to neutralize Malta.

If we compared the failed LW and RA bombing campaign against Malta during the first part of Oct. 42 and the Tunisia campaign, it seems to me that the Axis problem was the weak defensive power of their bombers which their fighter pilots could not effectively compensate if they operated against well integrated fighter defence. I don't have time to read the Shores' et al Malta the Spitfire Year (1991) but have to rely on Playfair's et al The Mediterranean and Middle East IV (1966) but Shores' article The Long Struggle for Malta in his Duel for the Sky (1985) is in agreement with the first book. Axis flew 2400 sorties against Malta in 9 days and the defending fighters flew 1115 sorties.Playfair p. 195 "...At first Axis used formations as big as 80 Ju 88s escorted by nearly double that number of fighters, but by 15th Oct. as few as 14 bombers were being escorted by nearly 100 fighters. By 18th Oct, after heavy losses in bombers, the enemy had given up using his Ju 88s altogether in favour of Me 109 fighter bombers...The British lost 30 Spitfires in the air ... and only 2 a/c - one Beaufighter and one Spitfire - on the ground. German records disclose the loss of 9 fighters and 35 bombers, some of which fell to the guns" and Italian losses were unknown. Later in same page"...so effective were the air defences of Malta that strikes against Axis shipping were carried out every night exept one, on which no enemy ship came within range of the island."

Shores, on the article p. 92 "...Again and again the formations of Ju 88s, protected by swarms of Messerschmitts and Macchis, attempted to fight their way through to their targets. And again and again they were thwarted."

On losses, on same page "...at least 30 Ju 88s were lost and 13 more damaged seriously, some of them to written-off levels...at least a dozen Bf 109s and MC 202s being shot down and another 10 or so badly damaged...27 Spitfires being shot down during seven days and more than 20 more crash-landing or suffering heavy damage..." "

 

[NZTyphoon]

Oh, good ole' Mikey has the report, but understandably its not something he wants to advertise too much on Spitfire performance history. Well of course that, the roll rate report on the Spitfires, fully rated Bf 109s in his comparison articles and so on.

Anyway here it is... you see, all you have to do is ask nicely. 8)

How about dropping the attitude and snide remarks about people and just concentrate on some useful discussion?

 

[Kurfürst]

How about dropping the attitude and snide remarks about people and just concentrate on some useful discussion?

How about taking your own advice..?

 

[Juha]

Hello Kurfürst
thanks for sharing the doc. It seems interesting.

Juha

 

[Kurfürst]

U R welcome Juha.