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REVIEW
La-5/7 vs Fw 190
JPTRR
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Posted: Saturday, September 17, 2011 - 09:04 AM UTC
Osprey has released yet another of their engaging DUEL series with La-5/7 vs Fw 190, Eastern Front 1942-45, and Randy Harvey [ HARV ] has brought it to us in another of his excellent reviews.




Link to Item

If you have comments or questions please post them here.

Thanks!
GastonMarty
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Posted: Saturday, September 17, 2011 - 10:14 AM UTC
I have several questions concerning this book, pertaining to the tactical use of the FW-190A/Fs, which is generally rife with gross misconceptions...

Since the book is ostensibly at least in part about the comparative tactical use of these aircrafts, I wonder if the following points, available from Soviet sources, have been emphasised. I am curious because these offer an unexpected insight into the relative use of the FW-190A and the Me-109G as well: From the 1943 Soviet book "Soviet Figther Tactics" and the Soviet magazine "Red Fleet", also 1943:

http://www.ww2f.com/eastern-europe/21828-russian-combat-experiences-fw-190-a.html
http://luthier.stormloader.com/SFTacticsIII.htm

-"The speed of the FW-190 is slightly higher than that of the Messerschmitt; it also has more powerful armament and is more maneuverable in horizontal flight."

-Since the FW-190 is so heavy and does not have a high-altitude engine, pilots do not like to fight in vertical maneuvers."

-"Throughout the whole engagement with a FW-190, it is necessary to maintain the highest speed possible."

-"In fighting the FW-190 our La-5 should force the Germans to fight by using the vertical maneuver."

-"When fighting the La-5, the FW risks a vertical maneuver only at high speed. Vertical-maneuver fighting with the FW-190 is usually of short duration"

My favourite:

-"Being very stable and having a large range of speeds, the FW-190 will inevitably offer turning battle at a minimum speed."

Johnny Johnson also thought the FW-190A out-turned the Me-109, and even his Spitfire Mk V in prolonged slow turns (it is the same as a Mk IX in turns), as did RCAF pilot John Weir: ""The Hurricane was more manoeuvrable than the Spit and, and the Spit was probably, we (Hurricane pilots) could turn one way tighter than the Germans could on a, on a, on a Messerschmitt, but the Focke Wulf could turn the same as we could and, they kept on catching up, you know."

More relevant, and especially interesting, is this other Soviet 1943 book text I like to keep handy:

"Germans will position their fighters at different altitudes, especially when expecting to encounter our fighters. FW-190 will fly at 1,500-2,500 meters and Me-109G at 3,500-4,000 meters. They interact in the following manner:

FW-190 will attempt to close with our fighters hoping to get behind them and attack suddenly. Me-109G will usually perform boom-n-zoom attacks using superior airspeed after their dive.

FW-190 will commit to the fight even if our battle formation is not broken, preferring left turning fights. There has been cases of such turning fights lasting quite a long time, with multiple planes from both sides involved in each engagement."

I think these consensus Soviet combat pilot observations are factually correct, and I would be curious to know if their unexpected conclusions are reflected in this book...

Gaston
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Posted: Sunday, September 18, 2011 - 11:22 AM UTC
I thoroughly enjoyed this book, too.

Consider the developmental irony--the Fw 190 entered the war as a radial engine king of the sky, while the LaGG entered as a badly-handling, poorly performing Russian equivalent of the Brewster Buffalo. The Fw became progressively heavier and had to saved by re-engining with an in-line, while the LaGG was improved with a radial, and became the La-5/7. Both the Fw 190D and the La-7 ended the war as top performers.
GastonMarty
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Posted: Sunday, September 18, 2011 - 12:20 PM UTC

The short-nose FW-190s were not "saved" by re-engining to an in-line engine... They remained, including the F, in full production until the end of the war...

Contrary to general opinion, the D-9 was considered superior to the As and Fs ONLY in high altitude speed performance, and especially climb rate performance, which did matter considerably in using vertical tactics (for which the FW-190s were probably not that well-suited in high-speed handling, this maybe extending to the D-9 itself)...

Vertical fighting itself was not necessarily highly useful in the lower altitude fighting of the late war period, and the high altitude bomber interceptions were not helped by the D-9's lower firepower...

The D-9 had, uniquely, 5 mm armored steel skin on the nose, which did make it useful in ground attack, as it added protection to the engine from frontal fire...

The D-9 was drastically inferior to the earliers As and Fs in every respect of handling, and could not out-turn Western Allied fighters in prolonged low-speed turns which the earlier short-nosed FW-190s could...

This is a 1946 evaluation (second link from top of thread):
http://forums.ubi.com/eve/forums/a/tpc/f/23110283/m/7891055058/p/1

Quote: "1-The FW-190D-9, although well armored and equipped to carry heavy armament, appears to be much less desirable from a handling standpoint than other models of the FW-190 using the BMW 14 cylinder radial engine."

Any advantage this airplane may have in performance over other models of the FW-190 is more than offset by its poor handling characteristics."

Gaston
JPTRR
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Posted: Monday, September 19, 2011 - 01:45 PM UTC

Quoted Text

The short-nose FW-190s were not "saved" by re-engining to an in-line engine... They remained, including the F, in full production until the end of the war...



The radial 190 remained a threat until VE day, yet were "saved" in that they lacked competitive high altitude performance in a war that was climbing increasingly higher; that combined with the increasing weight made the 190 more vulnerable and less formidable against fighters. Even on Freijagd sorties the hunters were becoming the hunted. It took the in-line Jumos to restore the power-to-weight ratio to make the Fw 190D, which in the estimate of many esteemed Allied pilots, was the best German piston engined fighter of the war. Even the great Eric "Winkle" Brown rated it as such, stating it was as good as the Spitfire XIV and P-51D.

Bear in mind that as the Fw 190 became heavier, it was relegated to attacking bombers while obsolescent Bf 109s, due to their superior engine at higher altitude, were assigned as top cover to take on the escort fighters.

The radial Focke-Wulfs remained dangerous, but only below 20,000 feet. That's why almost all Fw units were withdrawn from Defense of the Reich duties after D-Day, to fight Jabos at low and medium altitudes.


Quoted Text

Vertical fighting itself was not necessarily highly useful in the lower altitude fighting of the late war period



Superior performance in the vertical plane was, and has remained, the holy grail of fighter performance. In the 1950s, even when yank-and-bank performance was being marginalized by designers, vertical energy maneuvering was still a primary performance criteria.


Quoted Text

...high altitude bomber interceptions were not helped by the D-9's lower firepower...



Two cannon less than most 190As but one cannon more than the Bf 109G... And had the tactical situation been different, the Dora was able to be armed with the Mk 108 3cm cannon.


Quoted Text

...and could not out-turn Western Allied fighters in prolonged low-speed turns which the earlier short-nosed FW-190s could..



No discounting that every fighter should retain the ability to out-turn the enemy, but to quote a Spitfire Group Captain when told that the Spit V could still outturn the Fw 190A-4, "Turning doesn't win battles!"

So true, the Jumos powered 190s were not considered as good as the radial 190 in handling, yet in an arena where 85% of kills were made on the first pass, yanking and banking was not considered as important as the ability to race in, shoot, and keep going. Still, every pilot wanted the ability to outmaneuver any foe, whether to get into position to convert the shot, or to shake the bad guy off one's tail.

That in mind, the air war was still going higher, and speed and altitude were becoming more important than flinging the fighter about the sky. An within that criteria, the BMW Focke-Wulf had lost its value and needed saving. The Luftwaffe really did not have any choice -- they really did not have another follow-on fighter ready by summer of '44 (ME 262 not withstanding).

And with THAT in mind, that is why Bf 109s, Fw 190As and Fw190Fs (as well as Panzer IVs for the Panzerwaffe) stayed in production -- Germany could not afford to disrupt production -- better to have a continuing supply of second-best weapons today than better weapons (maybe) tomorrow.
GastonMarty
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Posted: Monday, September 19, 2011 - 04:30 PM UTC
The Spifire could easily pull 6 Gs or more, while the FW-190A likely could hardly exceed 5 Gs or so in turns without going into a tail-down mushing or wing drop that, in the mushing case, might yield 7 "Gs" on the pilot, but on a 5 G, or at best close to 6 G, turn only.

This mediocre high-G turn performance should not confuse us into thinking the FW-190A was out-turned by the Spitfire, at least not in the way "out-turning" is usually understood in common WWII speak, which is: Constant speed turning at around 3.5 Gs over several 360°s... In those circumstances, it was no contest, as Johnny Johnson himself describes:

http://img30.imageshack.us/img30/4716/jjohnsononfw190.jpg

If you do not believe the FW-190A out-turned, at low sustained speeds and lower Gs, the Spitfire, consider this quote from the very man you quoted who said, when told by test pilots that the Spitfire out-turned the FW-190A, "Turning does not win battles!" : His name was Alan Deere.

Admittedly he did not challenge, in his answer, what the test pilots told him... But that was likely only because he (wrongly) trusted test pilot evaluations above what his own combat experience showed him :

-Squadron Leader Alan Deere, (Osprey Spit MkV aces 1941-45, Ch. 3, p. 2: "Never had I seen the Hun stay and fight it out as these Focke-Wulf pilots were doing... In Me-109s the Hun tactic had always followed the same pattern- a quick pass and away, sound tactics against Spitfires and their SUPERIOR TURNING CIRCLE. Not so these 190 pilots: They were full of confidence... We lost 8 to their one that day..."

Another pilot's well-considered opinion show just how far behind the Spitfire was compared to the FW-190A, in sustained turns:

It is a quote from Hurricane pilot John Weir (click on John Weir link):

http://www.vac-acc.gc.ca/remembers/s..._101/SF_101_03

"A Hurricane was built like a truck, it took a hell of a lot to knock it down. It was very manoeuvrable, much more manoeuvrable than a Spit, so you could, we could usually outturn a Messerschmitt. They'd, if they tried to turn with us they'd usually flip, go in, at least dive and they couldn't. A Spit was a higher wing loading..."

"The Hurricane was more manoeuvrable than the Spit and, and the Spit was probably, we (Hurricane pilots) could turn one way tighter than the Germans could on a, on a, on a Messerschmitt, but the Focke Wulf could turn the same as we could and, they kept on catching up, you know."

For whatever reason, the huge difference in "static" wingloading is in reality irrelevant here (something almost all WWII test establishments failed to establish correctly in their testing of various WWII types, except for the Germans who did evaluate correctly the early needle-tip prop P-47D vs the Me-109G because the difference was so obvious: KG 200: "The P-47D out-turns our Bf-109G": Source: On Special Missions: KG 200)

As to the notion that turn fighting was "passe" and vertical boom and zoom fighting was the "Holy Grail", this depended very significantly on the types involved: Less than 10% of the combat seen in these 1300 combat reports excludes completely at least one full 360° circle turn:

http://www.wwiiaircraftperformance.org/p-47/p-47-encounter-reports.html
http://www.wwiiaircraftperformance.org/mustang/combat-reports.html

(The P-47 usually beats out the Me-109G in 2 to four 360° turns, while the P-51D goes on in two instances for 15 minutes: 45 consecutive 360° turns to the same side! The P-51 often "loses" the FW-190A, while the P-47D is often out-turned by the FW-190A by some margin. The Me-109G never succeeds once in doing that, unless briefly at high speeds and high Gs, often shedding a wing in doing so...).

Number of diving attacks on a lower target not itself diving, followed by a zoom: 0, or very near to that, in 1300 combat reports...

On that same site there is also a list of Spit Mk IX combat reports. Surprisingly, NONE of these involve combat of more than one 360° turn. Unlike the P-51 and P-47 endless turning battles, most Spitfire combat involves diving from above on a lower non-diving target and pulling up afterwards(!)... Or sneaking up on an unaware target... The Spitfire seemingly is hardly ever used in turning combat at low speeds...

This parallels Russian opinion of the Spitfire: It is unsuitable for prolonged horizontal combat (but can make one very hard turn), and it is excellent at combat on the vertical plane... In "Le Fana de l'Aviation" #496 p. 40: " Les premiers jours furent marqués par des échecs dus à une tactique de combat périmée dans le plan horizontal, alors que le Spitfire était particulièrement adapté au combat dans le plan vertical."

Translation: "The Spitfire failed in horizontal fighting, but was particularly adapted to vertical fighting"

In that same article, the Soviets even tried to remove the outer guns to improve the Spitfire's turn performance, to no avail...

[Two things worth noting in all these combat reports: The unreliability of the P-51 guns in all versions including the D, but truly epidemic on the earlier Bs, and the power of the Spitfire 20 mm guns, which often blew up the FW-190A instantly...]

This does seem to indicate that turn fighting was not at all obsolete, even in late 1944, but using it was heavily determined by the perceived abilities of the aircraft... In the case of the P-47, turn fighting seemed a veritable obsession of its pilots, and rightly so against the Me-109G, all the way down to on the deck climbing spirals at 140 MPH(!)... But not very effective against the FW-190A in horizontal turns... The P-51's mediocre turn rate, on the other hand, benefits a lot from reducing the throttle and coarsening the prop pitch at low speeds:

http://www.spitfireperformance.com/mustang/combat-reports/339-hanseman-24may44.jpg

The predominant boom and zoom tactics of the Spitfire did surprise me as to how stereotyped tactical choices were depending on aircraft type...

Gaston







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Posted: Saturday, September 24, 2011 - 07:17 AM UTC

Quoted Text

Bear in mind that as the Fw 190 became heavier, it was relegated to attacking bombers while obsolescent Bf 109s, due to their superior engine at higher altitude, were assigned as top cover to take on the escort fighters.



..'relegated' to attacking bombers ?... surely that was the prime task of the German fighter units defending the Reich. The Fw 190 A in its later variants 'became heavier' largely because it was specifically equipped for combating bombers at high altitude ! The 109s used for escorting the 'bomber destroyer' variants of the Fw 190 weren't obsolescent either, they were either the G-14 or G-10 or G-6 AS engined variants quite capable of out-climbing and out-turning P-51s...


Quoted Text

That's why almost all Fw units were withdrawn from Defense of the Reich duties after D-Day, to fight Jabos at low and medium altitudes.



..quite the opposite in fact. The Fw equipped units fighting Jabos were primarily those Western Front Geschwader that had always been on the Western Front ie JG 2 and JG 26. Virtually the only units on Defence of the Reich duties after D-Day were Fw 190 equipped Gruppen, specifically the Sturmgruppen, which as you rightly point out weren't designed to be flung about the skies but to slowly close en masse from astern on the bomber Pulks before blasting them with their 30mm cannon...the Sturmgruppen were moved to the Eastern Front in late January 1945 to take up ground-attack duties against Soviet troop and tank concentrations and flew their last missions against USAAF bombers over Berlin in March 1945...

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Posted: Saturday, September 24, 2011 - 06:52 PM UTC
Hi Neil,


Quoted Text

The 109s used for escorting the 'bomber destroyer' variants of the Fw 190 weren't obsolescent either, they were either the G-14 or G-10 or G-6 AS engined variants quite capable of out-climbing and out-turning P-51s...



The Bf 109G was obsolescent by 1943 in that it had peaked in development. It never had the development potential of the Spitfire or P-51, both of which got better without significantly sacrificing handling. Sure, more powerful engines were installed and the Kurfürst had a sizzling top speed but the 109's handling peaked with the Bf 109F. Messerschmitt was never able to correct the Bf 109G's awful rate of roll, terribly harmonized controls, and anemic range and firepower (yes, the MK 108 was a dangerous gun, but its low muzzle velocity made it ineffective against maneuvering fighters, and its small ammo load made landing those devastating rounds on a target iffy) and there really aren't any accounts of 109G's being able to out-turn a P-51 in 'standard' turning engagements; sure, Bud Anderson was initially out-turned by that 109 pilot but that was because he was much faster. Turn rate and turn radius are a factor of speed and G-load. Sure, a skilled 109 pilot could slow way down (about 140 mph IIRC, let those slats pop out, and hold a 4-G turn (until he ran out of gas or blood to the brain) and out-turn almost anything, but then he was drilling around a static patch of sky and vulnerable to successive passes from hit-and-run attacks.

Just as Colonel Baseler of the 325th would use his war-weary P-40 to humble new hotshot P-51 pilots, we can all find accounts of specific actions where a 109 out-turned a P-51 or a Spitfire under particular conditions; yet by and large, from just above sea level to 25,000, any Bf 109 in a 1-on-1 against any Merlin P-51 really did not have any chance to survive, aside from climbing. From what I recall of Osprey's P-47 vs Bf 109K DUEL book, the 109K was a 'one-trick-pony' -- go fast, try to get a shot with it's Mk 108 and twin 15mm guns, and try to land before running out of gas.

The point I made that initially started these treads is that the European air war was moving higher to counter heavy bomber raids over the Reich. Everything revolved around that. And BMW powered Fw 190s just were not competitive, and that is why the tired 109 had to be continually up-rated and lightened. Really, RLM saw the need to put a high altitude engine in the FW in mid-'42 or early '43.

And as far as FW and ME performance down low, in the book JG26 War Diaries I noted an irreversible trend after D-Day that even those "Top Guns of the Luftwaffe" were rarely exchanging 1 for 1, let along returning from sorties with more kills than losses.


Quoted Text


Quoted Text

That's why almost all Fw units were withdrawn from Defense of the Reich duties after D-Day, to fight Jabos at low and medium altitudes.





Quoted Text

..quite the opposite in fact. The Fw equipped units fighting Jabos were primarily those Western Front Geschwader that had always been on the Western Front ie JG 2 and JG 26. Virtually the only units on Defence of the Reich duties after D-Day were Fw 190 equipped Gruppen



That is counter to Osprey's Fw 190 Defence of the Reich Aces, Aircraft of the Aces 92. However, Sturmgruppen were not a consideration in that book.
GastonMarty
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Posted: Monday, September 26, 2011 - 02:13 PM UTC
I think Neil is more correct here: By late 1944 the proportion of Western Front single engine fighters was 70% FW-190A vs 30% Me-109G, and increasing...

There is no question the FW-190A was undertaking all roles in the West by late 1944, gradually edging out the Me-109G, and heavily used in the air superiority role as demonstrated by the common removal of the outer wing guns on As, and the heavy use of F-8s which similarly tipped the scale lighter because of that...

As for the Me-109G having no chance against the P-51 in single combat... The fact that they turned with each other for 15 minutes on end show they were well-matched in their mediocre turning ability... The P-51 could probably cut a much harder turn at high speed but was barely equal to the Me-109G at sustained turn speeds.

With the P-51 using "purple passion" 150 Octane fuel and 72" of manifold pressure, it could actually slightly out-climb the standard Me-109G-6, this being especially true for the "B" and "C" models.

You would think in June the introduction MW-50 injection on the G-14, with 1800 hp maximum for a full ten minutes over 1500 hp for three minutes previously on the G-6, would give the Me-109G a new edge, but the MW-50 injection could not be used in prolonged dive without risking blowing up the engine, and was subject to oil starvation on steep climbs, so it could only be used safely horizontally where its utility was limited... It also added 300 pounds to the weight...

The Me-109G was less expensive to produce than the FW-190A, and its characteristics were actually better suited to combat Soviet fighters on the vertical, so I would say it was slightly obsolete on the Western Front, but fully up to date on the Eastern front, where it outnumbered the Fw-190A.

Fighting a P-51D in a Me-109G was far from hopeless, except maybe at altitudes above 7-8 kms, but fighting the P-47D was probably noticeably harder at all altitudes except for climbing away...

Gaston



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Posted: Tuesday, September 27, 2011 - 01:31 PM UTC

Quoted Text

I think Neil is more correct here: By late 1944 the proportion of Western Front single engine fighters was 70% FW-190A vs 30% Me-109G, and increasing...

There is no question the FW-190A was undertaking all roles in the West by late 1944, gradually edging out the Me-109G, and heavily used in the air superiority role as demonstrated by the common removal of the outer wing guns on As, and the heavy use of F-8s which similarly tipped the scale lighter because of that...



That sounds right but my point is that, according to Osprey's Fw 190 Defence of the Reich Aces, Aircraft of the Aces 92, after D-Day the non-Sturmgruppen Fw's were withdrawn from Defense of the Reich duties to fight over the invasion fronts.


Quoted Text

As for the Me-109G having no chance against the P-51 in single combat... The fact that they turned with each other for 15 minutes on end show they were well-matched in their mediocre turning ability... The P-51 could probably cut a much harder turn at high speed but was barely equal to the Me-109G at sustained turn speeds.



The several comparisons I have read (German and Allied) state that the P-51 could out-anything a 109G at or above 25,000, although around 15,000 and below they were fairly matched. In few cases did a P-51 have trouble out-turning the ME.


Quoted Text

The fact that they turned with each other for 15 minutes on end show they were well-matched in their mediocre turning ability...



As for turning with each other for 15 minutes on end:
- what was the altitude?
- What was the respective fuel load?
-How proficient were the pilots?

Capt;. Eric Brown wrote, IIRC, that at sea level up to 2,000 m the 109 and P-51 were the same, that it became a battle of the engine.

I have browsed through some of the combat reports and other reports you have linked (No way I have time to cull through 1,300 reports) and really have not found any support that standard Fw190s/Bf109s turned as well as standard P-51s/Spitfires in standard encounters as stated in above posts. In fact, the link that goes to WW2 Aircraft Performance has many side comments highlighting how easily Mustangs out-turned everything they met.


Quoted Text

You would think in June the introduction MW-50 injection on the G-14, with 1800 hp maximum for a full ten minutes over 1500 hp for three minutes previously on the G-6, would give the Me-109G a new edge, but the MW-50 injection could not be used in prolonged dive without risking blowing up the engine, and was subject to oil starvation on steep climbs, so it could only be used safely horizontally where its utility was limited... It also added 300 pounds to the weight...

Very interesting. Thanks for this.


Quoted Text

The Me-109G was less expensive to produce than the FW-190A, and its characteristics were actually better suited to combat Soviet fighters on the vertical, so I would say it was slightly obsolete on the Western Front, but fully up to date on the Eastern front, where it outnumbered the Fw-190A.



Fully up to date on the Eastern front? The Yak 3 and La-5/7 could out-run, out-climb, and out-turn the 109 below 20,000. Recall that after the 14 July 1944 slaughter of Messerschmitts by Yak-3s, Kesselring ordered Jagdfliegers to avoid dogfights. In Messerschmitt Aces by Walter A. Musciano, he wrote, "Despite the enormous size to which the Red air force had grown by 1943, the Jagdwaffe held its own...with a fighter that had outlived its normal service life."

My whole original point is that the main German effort by 1944 was trying to stop the bombers, for which the Fw 190 was unsuited because it 's engine lost performance above 20,000. They needed to re-engine it and tried with the Jumos. That made a faster 190, but as we find in all of the documentation, its handling suffered.

(By the way, do you have any information on the 'standard' Fw 190A 5 with "exterior air intakes" as reviewed in WW2 aircraft performance? It showed the max. speed as 431 mph (!) although it stated only 250 kits were produced. Any idea what these were [I figure a two-speed two-stage supercharger] and why more were not fitted?)

I am sticking to the stories of the operational fighter pilots, the majority who found the P-51 superior to the Bf 109 and Fw 190. While there were easy kills and hard fights, history bears that out.
GastonMarty
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Posted: Tuesday, September 27, 2011 - 06:03 PM UTC

I agree with most of what you say about the Me-109G vs the P-51. The altitudes for the two 15 minutes continuous turning combats was on the deck, which prevented diving and thus offered a fair comparison.

The show "dogfight" has one P-51 pilot narrate his own continuous turning combat with a Me-109G, always the same turn, for 30 minutes (about 90 turns!).

I agree the P-51 often seems to out-turn the Me-109G easily in combat, but that is usually at a fairly high speed or at very high Gs, leading to a quick gain, or forcing the Me-109G to turn into a downward spiral, as diving helped the turn performance.

In level sustained speed turns, they were likely close, but the P-51 still sometimes had the edge.

Since the nose could not be pointed up steeply while turning, accepting a downward spiral meant the leading plane was below, in the spiral, and that was usually only delaying its inevitable defeat when the ground was reached: Exactly what happened in most cases... If given a choice, the turning will be kept as close to level as possible, by the lead aircraft, to at least keep a chance of pointing the nose at the enemy...

If the tailing pilot goes above the sustained 3.5 G to try to gain lead, that will force the other pilot to spiral down to beat the turn without slowing down too much... Level turning may or may not resume after that, but the ground will force it eventually...

When speed became sustained and on the deck, the P-51 often had trouble "closing the deal" on the Me-109G... Unless reducing its throttle and coarsening the prop pitch, a very peculiar low-speed "trick" I have pointed to in the Hanseman combat report (but several other similar reports point to this "trick" being taught unofficially at unit level).

http://www.spitfireperformance.com/mustang/combat-reports/339-hanseman-24may44.jpg

Note coarse prop pitch at low speed is the exact opposite use to the intended design use of the feature... (Practice beats theory in this case)

I have a (complex) theory for why the nose length leverage of the prop makes it beneficial to reduce the throttle from low speed: FW-190A, P-51, Me-109G pilots all report using reduced throttle continuously to make slower but tighter turns that are slower, but so much tighter that the rate of turn is actually faster (contrary to engineering assumption: See Hanseman report ).

The reason why the P-51 and the Spitfire sometime seem to turn tighter than the FW-190A is that they use high G turns (above 4 Gs) or turn at high speeds, where FW-190A's handling is very poor.

It is probably true they can beat the Me-109G in turns in almost all circumstances, but not the FW-190A.... IF the pilot is not afraid of its stall... (Of interest here is that P-51 pilots often describe FW-190A pilot as being "afraid to reef it in", suggesting the aircraft could do better in turns than the pilot was willing to pull: Given the higher weight and small wings, it is easy to see why inexperienced pilots thought: If it can't do it at high speed, why should it be any better at low speeds?)

One FW-190A Western ace described the FW-190A as far better turning than the Me-109G, and described his tactics as follows when engaging P-51s or any other Allied fighter, including the Spitfire:

Reduce throttle, open flaps partially and use horizontal turning tactics exclusively, and at slow speeds, accepting repeated head-to-heads if the enemy did not slow down or turn. He described that the choice was offered on the FW-190A for three different types of aileron chords: He always chose the widest chord, and widened it further by using field-mounted "spacer" hinges which increased aileron bite at low speed: This was crucial for low-speed turn performance, as it allowed more "bite" for the aileron to catch the stall in low speed turning (at the cost of lesser high speed roll performance).

Catching the stall was done by relaxing the pull-back on the stick slightly, and simultaneously using the ailerons to prevent the wing drop. He also mentionned the broader wood prop was a major advantage in low-speed turns, as it seemed to have more "bite" while near the stall.

He described being on the deck in a FW-190A-8, at low speed, and reversing a tailing P-51D and shooting it down in a mere two 360°s, the P-51 almost stalling as it tried to out-turn him. This is such a large disparity of turn rate it illustrates well the advantage of low throttle at low speeds: The disparity could never be so large if the P-51D had ALSO reduced throttle at low speed as he did himself, as the P-51 benefitted a lot from doing that: Read the Hanseman report above...

Karhila himself mentions the Me-109G's optimum sustained turn speed as a very low 160 MPH.... And he heavily stresses the use of continuous reduced throttle in sustained turns, while other pilots wrongly used full power he implies ...

I am convinced there is something fundamental about this use of reduced throttle that shows the physics of powerful nose-pulled single engine fighters is not properly understood at all. All in-line engined fighters changed to radials benefitted enormously from the shorter nose (despite being heavier in both the Ki-100 and La-5 cases), while the FW-190D-9 was inferior in turns and handling to its predecessor...

The Ki-100 was such a huge improvement over the Ki-61 that the Ki-100, in Japanese tests, could take on, alone, 3 Ki-84s and win, exchange pilots and then repeat the feat again...

One on one, the Ki-84 was considered to have no chance at all against the slower Ki-100 if combat was starting from equal altitude... Even from below the Ki-100 could win...

On "paper", the Ki-100 is barely any better than a regular Ki-61, and no better than a Ki-61-II. Clearly there is something not understood about these flight dynamics...

There seems to be something about sorter noses and a more rearward weight distribution that makes a big difference. The Ki-100 was even 200 lbs heavier than the regular Ki-61...

Gaston