Some thoughts on "combat effectiveness/performance" factors that are often hidden. (1 Viewer)

[ThomasP]

FWIW

In my notes I have:

The maneuver flap modification was included on the G-5 production line.

Correction, my notes actually say:

"Maneuver flaps entered production with the P-38F-15. The maneuver flap Mod. was subsequently included on the G-series production line."

 

[ThomasP]

Addition to my posts above re airframes equipped with maneuver flaps.

From the P-38D through G series PFOI manual revised 30 September 1944:

"Airplanes with serial numbers higher than 42-12667 and 43-2064 are equipped with maneuvering flaps."

Unfortunately, I have no idea which specific production series the s/n relate to.

 

[Greg Boeser]

121 P-38F-15 accepted August to October 1942, British order absorbed in USAAF

The problem is P-38G began acceptances in June 1942, did the G have the flaps from the start?

42-12667/12686 F-5A-1, accepted June 1942
42-12687/12766 P-38G-1, accepted June to August 1942
42-12767/12786 F-5A-3, accepted August 1942
42-12787/12798 P-38G-3, accepted August 1942
42-12799/12866 P-38G-5, accepted August/September 1942
42-12867/12869 P-38J-1, accepted September 1942
42-12870/12966 P-38G-10, accepted September to November 1942
42-12967/12986 F-5A-10, accepted November 1942
42-12987/13066 P-38G-10 accepted November/December 1942
42-13067/13126 F-5A-10 accepted December 1942/January 1943

wrathofatlantis = Gaston = Gen. Tlavok and probably other names.

Posting for many years now their idea of WWII air combat, it is about low speed turning, cutting throttles etc. It is about the idea the fighters that history says fought in the horizontal fought in the vertical and vice versa. There are a long line of quotes used to prove this and impressive sounding aerodynamic reasons given, except the people that actually know aerodynamics keep pulling the claims apart. Such trifling problems are ignored and more quotes are posted, factual errors are also ignored and so on. Expect lots of this before starting again.

What I like best is he'll reference a source, then when you read the source it actually does not support his argument.
Yes, cutting throttles does allow you to pull a tighter circle as you slow down, but only briefly. Then you have to increase power or you will either stall or have to flatten your turn circle. Same goes for using combat flaps. They improve lift but at a significant drag penalty.

 

[Steamed_Banana]

Increase power and / or dive, which is one reason why combats tended to move down...

 

[tomo pauk]

Wrt. the 'combat flaps' for the P-38 - my understanding is that there was no introduction of bespoke flaps, but rather that the existing (Fowler) flaps gotten an extra in-between setting, besides the fully retracted and fully opened.

 

[Steamed_Banana]

Wrt. the 'combat flaps' for the P-38 - my understanding is that there was no introduction of bespoke flaps, but rather that the existing (Fowler) flaps gotten an extra in-between setting, besides the fully retracted and fully opened.

Yes it's an important distinction. Combat flap settings were usually about 5-10 degrees from what I understand, though more on a few aircraft. Sometimes a bit more. So you get a bit more lift but with as little drag penalty as possible. A little bit of flaps also means you can engage them at higher speed. There is also usually of course a takeoff (around 15-20 degrees) and landing (30-40 degrees) flap setting.
It also depended on the type of flaps, fowler, 'butterfly', split, trailing edge etc.

P-38 had 8 degree flaps settings from what I'm reading.

Some aircraft (probably most, by the mid war) had a specific combat flap setting option, others just engaged the equivalent amount.

IIRC (somebody correct me if I'm wrong) Spitfires didn't have an in between flaps setting, they were either 'down' (landing) or 'up' - this is because lift was so good (by WW2 fighter standards) they didn't need flaps for takeoff and they could out-turn just about anything, at least in Europe.

On a P-40 they never made a combat flaps setting, but there was a switch on the control stick which could be engaged to the flaps which acted almost like a dimmer, so they could drop however much they wanted, 2 degrees, 20 degrees, whatever you wanted and could get away with.

Bf 109 also had a wheel which went 10 or 20 degrees.

Ki-44 (which didn't turn that well) had two settings, for 15 and 35 degrees.

 

[Dimlee]

The article highlights the Fw's limitations based on it's weight. Unable to sustain climbs, once its initial speed degrades, it can only engage in horizontal turning, except it can dive away to regain some speed. The comment the Atlanean highlights as proof of the Fw's superiority merely points out that the Fw is not prone to spin.
This is a comparison to the La-5.

Yes, of course.
My understanding was (unless I missed something, being lost in the lengthy posts) that the core Atlantean thesis has been: slow-speed turnfight as a superior manoeuvre, undervalued and not understood by... everyone else.
But I could misunderstand.

 

[Greyman]

Bf 109 also had a wheel which went 10 or 20 degrees.

The 109's flaps were controlled mechanically with the wheel and could be set to any intermediate angle between fully up/down (0-42.5 deg). Four complete turns of the wheel are required to fully lower the flaps.

I think confusion arises from the fact that the flap position is indicated in 10 degree increments.

A very simple and effective flap-position indicator is worthy of note. Lines painted on the slotted flaps at 10° intervals lie under the trailing edge of the wing and successively emerge into the pilot's view as the flaps are lowered. Take-off and landing positions are indicated by different coloured lines. - RAE

 

[Steamed_Banana]

The 109's flaps were controlled mechanically with the wheel and could be set to any intermediate angle between fully up/down (0-42.5 deg). Four complete turns of the wheel are required to fully lower the flaps.

I think confusion arises from the fact that the flap position is indicated in 10 degree increments.

A very simple and effective flap-position indicator is worthy of note. Lines painted on the slotted flaps at 10° intervals lie under the trailing edge of the wing and successively emerge into the pilot's view as the flaps are lowered. Take-off and landing positions are indicated by different coloured lines. - RAE

Wasn't there also a specific combat setting indicated on F and later?

 

[Geoffrey Sinclair]

42-12667 was an F-5A-1, first in the block 42-12667 to 42-13566.

Completing the early P-38G serial block and noting G-10 began acceptances in September 1942.
42-13127/13266 P-38G-10 accepted January to March 1943
42-13267/13326 F-5A-10 accepted March 1943
42-13327/13557 P-38G-10 accepted March/April 1943
42-13558 P-38K-1 accepted June 1943
42-13559 P-38H-1 accepted March 1943
42-13560/13566 P-38J-1 Accepted June 1943

43-2064/2184 is the 121 ex British order P-38F-15 accepted August to October 1942, 43-2185/2558 is the 374 ex British order P-38G-15 accepted October 1942 to March 1943, so largely accepted in parallel with the G-10. All the F-15 and G-15 are ex British order.

Apart from the H-1 and J within the 42-12667 to 42-13566 serial block, P-38H acceptances from May 1943, change over to the J in August 1943.

The USAAF Model Designation Army Aircraft 11th Edition of January 1945 says the G-15 was the same as the F-15 except for the G series engine change (V-1710-49/53 to -51/55), then says the H-1 is the same as the G-10 except for the change to V-1710-89/91, no further mention of F or G models.

G series acceptances September 1942 to May 1943 / G-10 / G-15 / Total
September / 3 / 0 / 3
October / 80 / 19 / 99
November / 52 / 72 / 124
December / 42 / 81 / 123
January / 51 / 100 / 151
March / 74 / 94 / 168
April / 124 / 8 / 132
May / 122 / 0 / 122

Total is 548 G-10 and 374 G-15

 

[Greg Boeser]

Yes, of course.
My understanding was (unless I missed something, being lost in the lengthy posts) that the core Atlantean thesis has been: slow-speed turnfight as a superior manoeuvre, undervalued and not understood by... everyone else.
But I could misunderstand.

Slowing down in a tight turn is a very good defensive maneuver if your attacker is diving on you. You evade their fire and get them to overshoot, and if you are in a Fw, you can reverse bank and nail them after they spill out in front of you.
This is what Jimmy Thach observed when dodging Zeroes. They tended to pull up too soon.

 

[BiffF15]

What I like best is he'll reference a source, then when you read the source it actually does not support his argument.
Yes, cutting throttles does allow you to pull a tighter circle as you slow down, but only briefly. Then you have to increase power or you will either stall or have to flatten your turn circle. Same goes for using combat flaps. They improve lift but at a significant drag penalty.

Greg you are correct. I even explained that I spoke with a USN Test Pilot friend (who flew a Mustang at TPS) to insure what I wrote was correct. To no avail. Shades of P39Expert…

 

[MikeMeech]

So that everyone can appreciate the magnitude of calling Clostermann an "outlier", in saying the FW-190A turned better at low speeds, and only at low speeds (where it mattered), here are a few of his fellow "outliers", starting with 3 quotes about turning as a whole, just to establish am overall context about the importance of low-speed turning, particularly late in the War (note that the Merlin P-51 is basically a 1944 and later type):

Item minus 2: (Just to establish priorities as seen by an ace P-51 pilot): P-51 ace pilot Joe H. Joiner (5 kills):

"Who can out-turn the other will win the air battle."

That's right Joe. Tell 'em…

Item minus 1: (A brief Me-109 vs Spitfire interlude): This is from a chapter in Ishoven's Messerschmitt Bf 109 at War. The chapter titled "Fighting the Spitfire" is authored by Erwin Leykauf: "For us the more experienced pilots, real maneuvering only started when the slots were out. For this reason it is possible to find pilots from that period (1940) who will tell you a Spitfire turned better than the Bf 109. That is not true. I myself had many dogfights with Spitfires and could always outturn them."

696 feet, really? This by the way, is very close to what the A6M2 Zero was said to do.

Item 0: Clayton Gross, P-51 ace: "I had a ten-minutes turning battle with a Me-109. Hard to say if I was a little better than him, or the machine was a little better, but I slowly gained over about 70 to a hundred circles." (If ten-twelve minutes probably more like 25-30 circles)

Just se we are clear about what WWII combat actually typically looked like in 1944 (compared to video games): Circles...

Maybe typical was not thirty circles, but you can imagine how common was 2-5.

----------------------------------------------------------------

Item 1 (FW-190-related, finally): James Goodson 15 kill P-51 ace;
"If you tried to turn at low level with the FW-190A, you were dead."

Item 2: Osprey "Long Reach" P. 125 (Lt. Col. E. W. Stewart, 355th FG): "The P-51 will out-turn the Me-109-- Greater difficulty is encountered in out-turning the Fw-190."

Item 3 -James E. Reed 33 rd FG (P-40F, Casablanca): "Regarding performance against the Me-109 and FW-190. The 190 was tough to out-turn. I could out-turn the 109, but it was hard to do. I, at times, had to drop a few degrees of flaps and slow down to out-turn it. On one mission dropping the flaps was not enough so I had to drop my landing gear to slow down enough to out-turn the Me-109 and get away from his fire. I think dropping the flaps and landing gear probably saved my life. I never had a one-on-one with the FW-190 so am not sure what I could do with it. I understand that it was harder to get away from than the Me-109."

While not a personal account, this is even better: According to him, general knowledge was that the FW-190A turned better than the Me-109G…

Clostermann an outlier? An outlier to what exactly?

Item 4: -Audio from the past [E16], Pierre Clostermann (18 kills, 10 FW-190 kills, RAF mission record holder at 432): "So there are legends on the Spitfire... Aaaah the legends… Legends are hard to kill. One of those legends is that the Spitfire turned better than the Messerschmitt 109, or the FW-190. Well that is a good joke... In fact all those who found themselves with a 109 or a FW turning inside them, at low speeds, well those in general did not come back to complain about the legend... Why? Above 280 to 300 knots, the Spitfire turned better than the Me-109. But, first and foremost, in a turning battle, the speed goes down and down and down and down, and at one point there comes a time, when the speed has gone down below 200 knots, that the Me-109 turns inside the Spitfire."


Don't you find that for a tactic that is supposedly useless and outdated, these 1943-44 pilots talk a lot about turning?


Item 5: A translated Russian article from "Red Fleet" describing Russian aerial tactics against the German FW-190, from Tactical and Technical Trends, No. 37, November 4, 1943 (One year of front line observations):

"-They [Me-109 and FW-190] interact in the following manner:

Me-109G will usually perform dive and climb attacks using superior airspeed after their dive. FW-190 will commit to the fight.

-A fairly good horizontal maneuver permits the FW-190 to turn at low speed without falling into a tail spin.

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

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

--------------------------------------------------------------

That's ONE YEAR of observations, and is like five items in one, from thousands of sources over one year. Outlier? Out-lier?

Item 6: "Le Fana de l'Aviation" #496, p. 40 (Spitfires in VVS use): "In the initial days the Spitfire failed in horizontal fighting, but was particularly adapted to vertical fighting."

Item 7: Osprey "Duels" #39 (La-7 vs FW-190), p. 69: "FW-190 pilots never fight on the vertical plane."

Item 8: P. 63, Vladimir Orekhov: "An experienced FW-190 pilot practically never fights on the vertical plane."

So much for Eric Brown... Hey, now there's an outlier....

Item 9: A translated Russian article from "Red Fleet", (an extra item): "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."

Item 10: -RCAF John Weir interview for Veterans Affairs: "The Hurricane was more maneuverable than the Spit. But the Focke-Wulf could turn the same as we could, and they kept on catching up, you know."

Item 11: -Johnny Johnson (top Spitfire ace, 36 kills) "My duel with the Focke-Wulf"; (low altitude, nearly on the deck)"With wide-open throttles I held the Spitfire [V] in the tightest of vertical turns [period slang for vertical bank]. I could not see him, for he was gaining on me: In another couple of turns(!) he would have me in his sights. I asked the Spitfire for all she had in the turn, but he hung behind me like a leech. It could only be a question of time."

Item 12: --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. Not so these 190 pilots: We lost 8 (Spitfire Vs) to their one that day."

Yep, Clostermann is an outlier… "Legends are hard to kill."

Hi
The 'Johnnie' Johnson quote from his book 'Wing Leader':

It is of interest to note that he appears not mention this happening again after the Dieppe incident in 1942 at all in the rest of the book, whether he is flying Spitfire V, VI or IXs. This could be why it is mentioned in that it was unusual?

Mike

 

[bada]

Now look at #11, November 5, 1942,
comparing a captured Fw 190 to the Spitfire IX and the P-38F.
The tests concluded that the Fw and Spitfire were roughly comparable up to 20,000 ft, with the Fw superior in maneuverability except in turn radius.
Against the P-38, the Fw was considered superior below 20,000 ft, inferior above.
The P-38 was considered better at low speed turns.

Wel, to be exact, this is the transcription of the chapter related to the P38F from the AFDU test of the FW190, july42 :

FW.190 v. Lockheed P.38F

77. The FW.190 was compared with an operationally equipped Lockheed P.38F flown by an experienced U.S. Army Air Coprs pilot. The two aircraft were compared for speed and all-round manoeuvrability at heights up to 23,000 feet. The FW.190 was superior in speed at all heights up to 22,000 feetwhere the two aircraft were approximately the same. The difference in speed decreases as the P.38F gains altitude, until at 23,000 feet it is slightly faster. The approximate differences ins peeds are as follows:-

At 2,000 ft.	the FW.190 is	15 mph. faster than the P.38F.
At 8,000 ft.	the FW.190 is	15 mph. faster than the P.38F.
At 15,000 ft.	the FW.190 is	5-8 mph. faster than the P.38F.
At 23,000 ft.	the P.38F is	6-8 mph. faster than the FW.190

78. Climb - The climb of the P.38F is not as good as that of the FW.190 up to about 15,000 feet. Above this height the climb of the P.38F improves rapidly until at 20,000 feet it becomes superior. The climbing speed for the P.38F becomes increasingly better.


79. Dive - Comparitve dives between the two aircraft proved the FW.190 to be better, particularly in the initial stage. During prolonged dives the P.38F on occasion was catching up slightly with the FW.190, but during actual combat it is unlikly that P.38F would have time to catch up before having to break off the attack.


80. Manoeuvrability - The manoeuvrability of the FW.190 is superior to that of the P.38F, particularly in the rolling plane. Altough at high speed the FW.190 is superior in turning circles, it can be out-tunred if the P.38G reduces its speed to about 140mph at which speed it can carry out a very tight turn which the FX.190 cannot follow.


81. The acceleration of the two aircraft was compared and the FW.190 was found to be better in all respects.


82. When the FW.190 'bounced' the P.38F and was seen when over 1,000 yards, the pilot's best manoeuvre was to go into a diving turn and if it found the FW.190 was catching it up, to pull up into a spiral climb, flying at its slowest possible speed. Altough time did not permit trials to be carried out with the FW.190 being 'bounced' by the P.38F, it is thought that the P.38F would stand a reasonable chance of shooting down the FW.190 provided it had a slight height advantage and the element of suprrise. If the pilot of the FW.190 sees the P.38F when it is just out of range, a quick turn in one direction followed by a diving turn in the opposite direction will give the P.38F a most difficult target, and as the acceleration and speed of the FW.190 in a dive builds up very rapidly, it is likely to be able to dive away out of range.

Just as comment, the 140mph is equivalent to the landing speed of the FW190, so no, i doubt any 190 would try to follow a P38 in a turn at that speed, even if they had the kamikaze bandana on the head.

 

[Greg Boeser]

Wel, to be exact, this is the transcription of the chapter related to the P38F from the AFDU test of the FW190, july42 :

FW.190 v. Lockheed P.38F

77. The FW.190 was compared with an operationally equipped Lockheed P.38F flown by an experienced U.S. Army Air Coprs pilot. The two aircraft were compared for speed and all-round manoeuvrability at heights up to 23,000 feet. The FW.190 was superior in speed at all heights up to 22,000 feetwhere the two aircraft were approximately the same. The difference in speed decreases as the P.38F gains altitude, until at 23,000 feet it is slightly faster. The approximate differences ins peeds are as follows:-

At 2,000 ft.	the FW.190 is	15 mph. faster than the P.38F.
At 8,000 ft.	the FW.190 is	15 mph. faster than the P.38F.
At 15,000 ft.	the FW.190 is	5-8 mph. faster than the P.38F.
At 23,000 ft.	the P.38F is	6-8 mph. faster than the FW.190

78. Climb - The climb of the P.38F is not as good as that of the FW.190 up to about 15,000 feet. Above this height the climb of the P.38F improves rapidly until at 20,000 feet it becomes superior. The climbing speed for the P.38F becomes increasingly better.


79. Dive - Comparitve dives between the two aircraft proved the FW.190 to be better, particularly in the initial stage. During prolonged dives the P.38F on occasion was catching up slightly with the FW.190, but during actual combat it is unlikly that P.38F would have time to catch up before having to break off the attack.


80. Manoeuvrability - The manoeuvrability of the FW.190 is superior to that of the P.38F, particularly in the rolling plane. Altough at high speed the FW.190 is superior in turning circles, it can be out-tunred if the P.38G reduces its speed to about 140mph at which speed it can carry out a very tight turn which the FX.190 cannot follow.


81. The acceleration of the two aircraft was compared and the FW.190 was found to be better in all respects.


82. When the FW.190 'bounced' the P.38F and was seen when over 1,000 yards, the pilot's best manoeuvre was to go into a diving turn and if it found the FW.190 was catching it up, to pull up into a spiral climb, flying at its slowest possible speed. Altough time did not permit trials to be carried out with the FW.190 being 'bounced' by the P.38F, it is thought that the P.38F would stand a reasonable chance of shooting down the FW.190 provided it had a slight height advantage and the element of suprrise. If the pilot of the FW.190 sees the P.38F when it is just out of range, a quick turn in one direction followed by a diving turn in the opposite direction will give the P.38F a most difficult target, and as the acceleration and speed of the FW.190 in a dive builds up very rapidly, it is likely to be able to dive away out of range.

Just as comment, the 140mph is equivalent to the landing speed of the FW190, so no, i doubt any 190 would try to follow a P38 in a turn at that speed, even if they had the kamikaze bandana on the head.

And that is the rub of it. The Focke Wulf had a comparatively high stall speed. This increases as G increases.

 

[SaparotRob]

Slowing down in a tight turn is a very good defensive maneuver if your attacker is diving on you. You evade their fire and get them to overshoot, and if you are in a Fw, you can reverse bank and nail them after they spill out in front of you.
This is what Jimmy Thach observed when dodging Zeroes. They tended to pull up too soon.

I think it was in the movie "G-d is my Co-pilot", this very scenario was dramatized.
Anyone remember the line: "Out of ammunition, eh Yank?"

 

[SaparotRob]

Hi
The 'Johnnie' Johnson quote from his book 'Wing Leader':
View attachment 875186
It is of interest to note that he appears not mention this happening again after the Dieppe incident in 1942 at all in the rest of the book, whether he is flying Spitfire V, VI or IXs. This could be why it is mentioned in that it was unusual?

Mike

Boy, talk about cliffhangers!
How did he lose the Wurger? Was it hit by the AA from the ships? Did JJ shoot him down or did they just part ways? I'm pretty sure someone here might know who the LW pilot was.

 

[MikeMeech]

Boy, talk about cliffhangers!
How did he lose the Wurger? Was it hit by the AA from the ships? Did JJ shoot him down or did they just part ways? I'm pretty sure someone here might know who the LW pilot was.

Hi
Johnson did not know what happened to the FW190, he was rather busy:

Mike

 

[ThomasP]

Hey WrathofAtlantis, and anyone else who might be interested,

re

Real minimum radius is 1025 ft Spit I, Hurricane I 800 ft, Me-109E 880 ft.

The 1025 ft radius of turn is from a test of a Spitfire Mk V conducted at 20,000 ft – as opposed the 696 ft radius of turn for a Mk I at 12,000 ft.

 

[wrathofatlantis]

Hey WrathofAtlantis, and anyone else who might be interested,

re


The 1025 ft radius of turn is from a test of a Spitfire Mk V conducted at 20,000 ft – as opposed the 696 ft radius of turn for a Mk I at 12,000 ft.

I know, and the 20 000 ft 1025 ft value is for a clipped wing Mk V, while the Mk V full wing is quoted as 975 feet at 20 000 ft.. A loss of 50 feet with the clipped wing.

I think these are real flown values with a real aircraft. They are quoted as real flight test values by a front-line Spitfire pilot in his memoir.

However the BA 1640 "696 feet" value has no date, no pilot name, no airframe number, and is explicitly stated by report BA 1640 (where it is found) as calculated, and the only numbered airframe with actual flight dates associated with that (aerodynamicist-written) paper is the captured Me-109E at 885 feet, a likely real number from which the Spitfire Mk I numbers were probably derived by calculations. (800 feet by the Hurricane in that document is likely real as well, since it is in line with numerous first-hand accounts that peg the Hurricane as vastly better turning than the Spitfire, and slightly better turning than the Me-109E.)

I do not believe the Spitfire radius improved by a gigantic 280 feet (!!!) in just 8000 feet... 12000 to 20000... In fact, I believe peculiarities of the Spitfire's thin wing may have allowed barely any improvements all the way down to ground level. The Spitfire wing seems to have worked at its best above 20 000 feet, and Clostermann, who described the notion that the Spitfire out-turned both German types at 200 knots as "a die hard legend" and "a beautiful joke" [literal translation meaning more like a "a good joke"], also says that above 25 000 feet the Spitfire's handling was massively superior to both German types...

Yes, there is a large drop in air pressure between 0 and 15 000 feet, but I also think the wing's turn behaviour under changing pressure was not necessarily linear to that drop.

In some extreme cases the roll rate actually improved with altitude, and I would be curious to see data showing Spitfire turn radius decay with altitude (by which I mean not the calculated BA 1640 Spit I chart...), as I suspect it was exceptionally low compared to most other types. Which means the 975 feet value for the full wing Mk V at 20 000 feet will not improve much, if at all, near the ground. This would match combat accounts and what Clostermann says. They were peculiar beasts, these things, and the data we have is incredibly fragmented, not to mention mixing-in calculated values and barely mentioning what they are...