Bf-109 vs. Spitfire....

[Glider]

Well sorry but you have presented no reliable source which contradicts it so far I'm afraid Claidemore. And seeing that the Bf-109 can turn as well as the Spitfire but can climb faster, I don't see why it wouldn't be an effective maneuver.

I still think you must be in politics or PR.

By the way what source do you have for the comment that the standard Luftwaffe evaision against a spit was a climbing tight turn. Nice statement but nothing to support it.

I have a copy of Duel of Eagles signed by Galland and Bader. In a book on his paintings Robert Taylor explains that he had to put a lot of effort into the composition of the painting. In the end he shows the Spitfire going into a turning climb. Bader and Galland agreed to the compositon, both agreeing that it looked good, showed the 109 to be on the offensive and that the Spit was safe.

 

[parsifal]

I dont profess to be any sort of expert in this, but something is nagging in the back of my head that during the Battle Of Britain standard Luftwaffe 109 tactics were to dive away, which was strange, becauise in a dive (according to this author, whom I canno remember) the 109s controls tended to freeze up and become incredibly stiff. This problem, apparently was made worse by the small and cramped cockpit of the 109. This account also said that with its direct fuel injection engine, the 109 could outclimb both the early marks of Spitfire and the Hurricane

I will try and find the details of this author.....perhaps it is an innaccurate account

 

[Colin1]

...during the Battle Of Britain standard Luftwaffe 109tactics were to dive away, which was strange, because in a dive (according to this author, whom I cannot remember) the 109s controls tended to freeze up and become incredibly stiff

This problem, apparently was made worse by the small and cramped cockpit of the 109

the controls of all the aircraft (Bf109, Hurricane and Spitfire) would freeze up in a prolongued dive. The effectiveness of the bunt (pushing the nose down in negative g and diving away) was useful in the short term.
If the Spitfire attempted the same manoevre, it would starve its carburated engine for a few seconds; if it attempted to circumvent this fuel starvation by rolling and then following, it would still lose precious seconds on the fleeing Bf109.

Cockpits of all combatants too, were cramped, I don't see how this would have affected the control surfaces at high speeds.

 

[Glider]

It is of course correct to say that all aircraft had the controls stiffen with speed the 109 E-G was more heavily impacted than most. I don't know about the K that was very different.

 

[Kurfürst]

Recommended reading:

Kurfürst - R.A.E. - Messerschmitt Me.109 Handling and Manoeuvrability Tests
Kurfrst - A.F.D.U. Tactical Trials - Me.109F aircraft

Dive recoveries do not seem too problematic as long as the operating instructions are followed: keep in mind that Me 109 manuals instructed the pilot not to trim into the dive, but keep a forward pressure on the stick.

I can't say it positively, but I believe the elevator gearing on the 109K was the same as before, altough for the late G and K it seems an alternate control gearing was also present (projected?), which would mean more limited maximum deflection angles for the elevator, and consequently, more mechanical advantage for the pilot on the stick.

On the Spitfire the elevator forces were a magnitude lighter (4 lbs/G vs 20 lbs/G on the 109s), but this appears to have been a bit too much, and created other problems, with so small stick movements the aircraft was difficult to be controlled precisely on the stall boundary, especially in combat, and there was a realistic danger of just snapping the aircraft in two by overloading it in recovery or in high-G turns. Early Spitfire manuals specifically mention this characteristic.

 

[claidemore]

I've never heard any reports of a Spitfire breaking in two during a high G pullout, but there are reports of 109s losing wings doing the same. Spitfires tended to bend rather than break, I offer the PRMk XI that achieved a +.9?mach number in a dive as an example.

Soren: 109's climbed faster?

I believe a 109E could outclimb a Mk 1 Spitfire with 2 speed prop and 87 octane fuel. With constant speed prop and 100 octane, afaik the Spitfire had the better climb rate.
109F vs Spitfire MkV the 109 had the advantage early on or against tropicalized MkVs with Vokes filters, but once boost was increased in the Merlin 45, the Spitfire again had the advantage.
Spitfire Mk IX vs any 109 model, the Mk IX outclimbed them all with climb rates as high as 5700 ft/min. The highest documented climb rate for the 109K with DB605 and 1.98 ata was 4900 ft/min. 'Operational 109Ks would have had a max climb rate of 4429 ft/min @ s.l. against 18lb boosted Mk IX which had a climb rate of 4620 ft/min @ s.l.

Point is, it would be innacurate to make a broad sweeping claim that 109s climbed faster than Spitfires. Against other fighters, perhaps.

Contradictory to your statement that the standard evasive manuever of the 109 vs the Spitfire was a steep climbing turn, it was the Spitfire pilot that could use the climbing turn to force the 109 into a flick stall and turn the tables on it.

 

[Juha]

Hello Claidemore
there were some cases with early Mk Vs (IIRC), re Quill's memoirs, but the problem was temporarily corrected by adding bob weight to elevator control run while permanent solution was developed.

Juha

 

[Juha]

On climb
at least Spit VIII, even with under fuselage bomb rack climbed better than 109G-8, especially after 2nd stage kicked on.

Juha

 

[Kurfürst]

I've never heard any reports of a Spitfire breaking in two during a high G pullout, but there are reports of 109s losing wings doing the same. Spitfires tended to bend rather than break, I offer the PRMk XI that achieved a +.9?mach number in a dive as an example.

Oh, there are plenty, but not on certain sites. Didn't the Spitfire had these little fences on the wing top, exactly because skin wrinkling, failurues?

But for example the Mk II manual also instructs the pilot to caution:

With constant speed prop and 100 octane, afaik the Spitfire had the better climb rate.

Do you have figures for the Mk I and E model at maximum output? I have not seen one yet.

109F vs Spitfire MkV the 109 had the advantage early on or against tropicalized MkVs with Vokes filters, but once boost was increased in the Merlin 45, the Spitfire again had the advantage.

I would have the check the figures, but I kinda doubt that - the boost was also increased on the 109F, in early 1942. Sadly there are no good figures for these, or for the +16 Spit Vs (the one we have is a rare and heavy 4 cannon version).

Spitfire Mk IX vs any 109 model, the Mk IX outclimbed them all with climb rates as high as 5700 ft/min.

Again, only on certain sites. The early 109G certainly had a climb advantage over the contemporary Spitfire IXF, especially with GM-1, under which condition the Mk IX (any model) simply cannot compete. As for the 5700 ft/min climb rate, its not realistic, or comparing apples to apples: it was done with, IIRC, a half loaded Spitfire IX, which had its radiator flaps in minimum drag position. The Germans trials assumed the radiator flaps in a moderately open position, and fully loaded aircraft.

The comparable figures would be of course at full take off weight, and radiator flaps in the climbing position. There is one trials with a 109G-2 with the radiator flaps in minimum drag position, and it does some 4800 fpm, that is, using the 30-min rating..

 

[claidemore]

Kurfurst:
Skin wrinkling and a note of caution in a Mk II pilots manual is a long way from breaking in two.

I am well aware of your feelings about certain web sites, however, I started researching Spitfires nearly 30 years ago, long before the internet became the 'information highway'.

 

[FLYBOYJ]

Oh, there are plenty, but not on certain sites. Didn't the Spitfire had these little fences on the wing top, exactly because skin wrinkling, failurues?

Gotta jump in here........

Those fences were to support the skin structure above the wheel well which not only wrinkled due to aerodynamic loads, but mostly by ground crews walking over them.

Below is a Mk I wing drawing - there is no reinforcing structure in that area.

 

[drgondog]

IIRC - the Spit had two flight control issues. One the wing, while long in chord, was not stiff enough per se to be immune to control reversal in high g tuening manuevers. Occasionally the wing/aileron forces would 'torse' the tip area, twisting the tip region to a High AoA and create an opposite direction roll.

The second is that some of the earlier (pre IX) Spits did los some wings in High g pullouts - but ill defined causes. The Mustang of course had similar failures until the uplock kits solved the 'gear drop/gear door open' issue for the high g pullout and the stiffer ammo door eliminating the 'local increase in wing camber' in the transonic region.

Claidmore - what do you have on the above?

 

[claidemore]

I've heard of wings bending, wrinkling, and rivets popping out and I've heard of Spits that augered in.
A Canadian pilot (Buck McNair I think) once got a Spit IX out of a (nearly)terminal dive by trimming, which the manual doesn't reccomend. I know that when they started dive bombing with MkIXs after D-Day, there were problems with wings wrinkling and bending, and they imposed limitations on the angles they should dive at.

This is the first I've heard of possible wing structure failure in Mk Vs. I'm curious to know what form these structure failures took. My guess is wrinkling, bending and popped rivets.

Interpret the precautions in the Spit II manual as you will. It says the wings will certainly fail if the 10g limit is "much" exceeded. How much is "much"?

The spar on the Spitfire wing was exceptionally strong and springy. I recently watched a Youtube video of a 30mm Mk108 cannon test on a MkII Spitfire wing. A single shot blew a huge hole in the wing, but the spar was still holding the wing in place.

 

[parsifal]

Ive read that the Spit was unsuitable for conversion to a 40mm conversion in the same way as the Hurricane. I believe the reason was because of the relative weakness in the wings. Any truth to that. If not, why want the Spit as successful as the Hurricane, or the Typhoon for that matter in the FB role? Is this relevant to this debate????

 

[Glider]

This is the first I've heard of possible wing structure failure in Mk Vs. I'm curious to know what form these structure failures took. My guess is wrinkling, bending and popped rivets.

.

It wasn't, it was a problem with the CG moving as the planes became more heavily loaded as time went on with extra equipment. Once recognised it was soon fixed.

I am confident Kurfurst knows this, as its one of those things that keeps getting raised every so often.

 

[parsifal]

i found this on the Net, from a guy called Bob Best. Its a good read, if nothing else...

"It is often stated that the Spitfire and Hurricane could both out-turn the Bf109. In his memoirs, Spitfire pilot Alan Deere claimed that it was impossible for a Bf109 to follow him in a turn, and that a hard defensive turn would quickly turn the tables on an attacking German. However, some sources claim the exact opposite, and some - but not all - German pilots also state that theirs was the better turning mount. Who, then, is right? How much difference did the aircraft flown make to the outcome of the Battle of Britain?

In making a comparison, there are several variables to consider. Altitude is one variable, as the German machine is held to be superior at higher altitudes by virtually all sources. Pilot quality is another factor, and it is this which may have made the Messerschmitt seem less maneuverable in combat for a couple of reasons.

First, many of its pilots believed it was not structurally sound. Its wings were both small and thin - so thin that prominent bulges were needed to house the breeches of its wing-mounted guns. The undercarriage was mounted on the fuselage rather than on the wing spar, the latter not being strong enough to withstand the impact of landing, which also gave it a dangerously narrow undercarriage track. The tailplane had bracing struts to cure structural problems resulting from engine vibration. The German machine looked light and dainty and its pilots simply did not trust its strength, although it was more than adequate given the light weight of the aircraft as a whole. In fact the whole design philosophy of the machine had been to make the wings as small and thin as possible to give maximum speed and maneuverability, which also dictated the overall small size of the plane to keep its weight to a minimum.

Second, when it was approaching its limits of low-speed handling, its leading edge slats automatically deployed, with a loud bang clearly audible over the engine roar! Although still having a considerable margin before stalling once the slats deployed, most pilots would back off their turn at that point, believing they were right on the verge of stalling. Many others did not even reach this point, and used the point of the slats deploying as the limit of safe performance, flying their aircraft in order to prevent their deployment at all. In this way these slats hindered their machines maneuverability, rather than being used to enhance it as was intended. This was a deficiency of the pilots, rather than of the designers, but when flown without the assistance of the slats the Bf109 would certainly be less maneuverable than its opponents.

An opposite fallacy exists with regard to the Bf109's ability to escape from the Spitfire by diving away. Early in the Battle, Spitfire pilots gave up the chase as considerable distance would be lost initially by the Spitfire having to roll before diving to prevent engine cut-out. However, as some pilots, through ignorance or frustration, followed they found that the 109 would have to pull up sooner or later, and when they did pull up it was done gently to avoid overstressing the thin wings, which was a genuine weakness of the design. The Spitfire pilots had no such fear, as their larger, thicker wings had a hefty "leaf-spring" spar which conferred enormous strength, and could simply "cut the corner" when pulling up their nose to make up their lost ground. Furthermore, diving to a lower altitude played to a strength of the Spitifre, as its performance was better at low altitude than high altitude, where the 109 had the advantages.

This is itself a factor to be considered in this comparison was the captured Bf109 that the British tested. They did not have an oxygen bottle for their captured Bf109, so tested it at only low to medium altitudes, where they thought combat would take place anyway. At these altitudes the result was indeed that both the Spitfire and Hurricane could out-turn the Bf109, and this was reported to the squadrons, whose pilots would have reacted in combat according to this perceived strength. Later, well after the Battle was over, testing at higher, "combat" altitudes showed the opposite to be true at these heights. Yet pilots in the Battle had consistently confirmed what the initial testing had told them, and claimed they were able to out-turn the German machine at all altitudes!

Finally, in assessing the merits of the machines, there is one final variable - the improvements made to the Spitfire and Hurricane between May and October, or more precisely, to their powerplant. Both started their service careers with two-blade fixed-pitch propellors being turned by an engine running on 87-octane fuel. In 1938 production of both types switched to a three-blade two-pitch propellor. To be more precise, this meant the engine was changed to a new version of the Merlin which could accomodate the new propellor, and this changeover caused some production delays. Since supplies of the newer engine were scarce, rather than convert earlier examples many of them were withdrawn from front-line service and placed in Operational Training Units, where their performance was not critical but they still served a more than useful function. With the Hurricane, however, sheer weight of numbers produced meant many two-bladers stayed in front-line squadrons, and numerous examples served in the battle for France. In fact, the majority in France were two-bladers, and having less-than-sparkling performance, these may have had something to do with the German assessment of the Hurricane as being markedly inferior. It was, but the margin was not as great as they thought.

The next change was to upgrade the propellor from a two-pitch to a variable-pitch. This change started only in early 1940 on the production lines, but there was no program put in place to upgrade existing examples. It was only when Geoffrey de Havilland sent teams out to the squadrons on his own initiative - and in hope he would later be paid for the work - that the older aircraft were all updated. These mobile conversion teams would arrive at a squadron, fit one propellor in front of the local fitters, assist with the conversion of a second, then just supervise the third. This done, enough kits were left for the whole squadron and they were on their way. This program started in July and was finished by mid-August.

The final upgrade was to the petrol. In 1940, producing 100 octane fuel was a complex process and the plant to produce it on a commercial scale did not exist in Britain. However, supplies had been imported from overseas and stockpiled from well before the war. In May 1940, these supplies were released to squadrons and the effect was startling to the pilots, as their Merlins went from 1,030 to 1,310 horsepower. This gave marked improvements to acceleration and climb rate, although the extra weight of the armour and radios then being fitted offset this slightly.

The net effect of these incremental changes was that performance of the British machines varied wildly. Within six months, the Luftwaffe went from facing the Hurricane Ia with a two-bladed wooden propellor and a Merlin II engine producing 990 hp, to facing the new Spitfire IIa with a constant-speed propellor and a 1,175 hp Merlin XII engine, while their own Bf109E's performance remained constant. Add to this that even similar aircraft vary in performance from example to example, and it is no wonder that performance comparisons are so difficult and opinions are so varied!

Finally, how an aircraft is flown in combat will differ from the way it is flown in clinical trials. This could also have resulted in a self-fulfilling prophecy. Perhaps, having been told their mounts turned tighter as a results of their own testing, RAF pilots always tried to turn inside their opponents. If they were the better pilots or if conditions were favourable they may have done so, scored a kill and lived to tell the tale of how they did it, perpetuating the myth. If not....


What can be said with certainty is this: the performances of Bf109 and Spitfire were very close, with any edge either held in any area being only minor. Even the Hurricane only lagged behind its contemporaries in speed, but compensated with far greater resilience. Man, not machine, would have made the major difference in clashes between these aircraft."

 

[Juha]

Hello
IIRC in his memoirs Quill tells that after some accidents he tested high g pullout in early Mk V and the plane disintegrated IIRC during Quill's black out.
But as I wrote the problem was temporarily corrected by adding bob weight onto elevator control cables while permanent solution was developed.

External wing reinforcing stakes can be found only in some/many Mk Vs IIRC, late and earlier marks didn't have them.

Juha

 

[Juha]

On turning
IMO with equal pilots Spit usually outturned 109 but good 109 pilot could outturn average Spit pilots. Having seeing Rall grinningly telling that he did it, otherwise he would not has been sitting where he sat. Bär, during the BoB highest claiming LW NCOpilot, also had habit to fight horizontally during the BoB, not always successfully. He was once shot down into drink and IIRC once just made it to France.

Juha

 

[Soundbreaker Welch?]

As I see it the Spit was a lovely plane to fly, the 109 not so much.

It still had an impressive kill ratio though.

 

[Glider]

This might be of interest

thought I remembered reading an interview on this subject many years ago- and finally found it in a yellowed copy of Alfred Price's 'Spifire At War' (published 1974). It's germane to this discussion (as my teacher used to say) because the person being interviewed is none other than Mr Eric Newton who spent the war with the Air Accident Investigation Branch. He was still employed by them as an investigator in 1974- the time of the interview- so presumably still had the facts at his fingertips. This body was, and is, independent of the RAF.

Mr Newton was called in to investigate Spitfire crashes which could not be immediately attributed to pilot error (the same crashes which are detailed in Morgan and Shacklady). He says:

"Out of a total of 121 serious or major accidents to Spifires reported to us between the begining of 1941 and the end of the war, 68 involved structural failure in the air. Initially the most common reason for such failures, with 22 instances in 1941 and 1942, was aileron instability. The symptoms were not at all clear cut: the aircraft were usually diving at high speed when they simply fell to pieces. Only after one of the pilots had survived this traumatic experience and parachuted successfully were we able to find the cause. During his dive he saw both of his ailerons suddenly flip up, producing an extremely violent pitch- up which caused the wing to fail and the aircraft to break up. In collaboration with RAE we did a lot of tests and found that aileron up- float was made possible by stretch in the control cables; in those days tensioning was a hit or miss affair with no compensation for temperature. On our recommendation the RAF introduced a tensometer which ensured accurate tensioning of the controls; this, and the simultaneous introduction of metal surfaced ailerons ('42/'43), cured almost all the cases of aileron instability in the Spitfire.

The next most serious cause of structural failure in the Spitfire was pilots overstressing the airframe. She was extremely responsive on the controls and one must remember that in those days there was no accelerometer to tell the pilot how close he was to the limit. So it was not difficult to exceed the aircraft's 10G ultimate stress factor (what was the 109's?- Berkshire) during combat or when pulling out from a high speed dive; during the war we were able to put down 46 major accidents to this cause, though undoubtedly there were many other occasions when it happened and we did not see the wreckage. Incidentally, if there was a structural failure in the Spitfire it was almost inevitably the wing that went; the fuselage was far less likely to fail first (the same for most low wing monoplane fighters?-except the Typhoon?- Berkshire).

I once asked a very senior RAF officer why the accelerometer- technically a simple instrument- was not introduced during the war. He replied that he was sure it would have an adverse effect on the fighting spirit of the pilots (same was said re the parachute in WW1!- Berkshire).

Whether that would have been so I cannot say. But I do know that when they finally introduced the accelerometer into service in the Hunter in 1954, and began educating the pilots on structural limitations and the dangers of overstressing, accidents to this cause virtually ceased.

After structural failure the next largest category of accidents proved on investigation to have followed loss of control by the pilot (36 cases). Of these 20 occured in cloud and could be put down to pilot error; one must remember that in the rush to get pilots operational instrument training was not up to peacetime standards. A further 13 accidents were shown to have been caused by oxygen starvation; the oxygen system had been used incorrectly with the result that the pilot had passed out and the aircraft had crashed. As a result of our investigations the system was modified to make it easier to operate.

The remaining 3 accidents in the loss of control category were initiated by the pilot pulling excessive G and blacking himself out.

Engine failures and fires contributed a further 17 accidents, and the remainder could be put down under the 'miscellaneous' heading (long story here about fuel leaks and explosions on the ground- Berkshire)

As I have mentioned we investigated a total of 121 Spitfire accidents during the war. The causes did not always fit simply into neat categories mentioned above. For example, a pilot might lose control in cloud and his aircraft then broke up in the ensuing dive due to aileron instability- in that case the accident would have been listed under two categories. There were one or two accidents caused by the light- weight plastic bucket seats fitted to some batches of Spitfires. The trouble was they were not strong enough and if there was a heavy pilot who pulled a bit of G they tended to collapse- on to the elevator control runs which ran underneath. We soon had that type of seat replaced.

In the nature of my work I tend to concentrate on an aircraft's failings and ignore its good points; but how safe was the Spitfire? I think the figures speak for themselves; a total of more than 22,000 were built, and we were called in on only 130 occasions- and in not all of those was the Spitfire at fault. If one considers that she was not a simple trainer built for ease of handling, there can be no doubt that the Spifire was a remarkably safe little aircraft."

To summarise:
There were 121 Spitfire crash investigations between 1941 and May 1945 involving serious structural failure:
22 aileron instability
46 pilot overstressed airframe
20 pilot error in cloud
13 misuse of oxygen system- pilot error
3 pilot blacked out
17 engine failure/fire