Gunther Rall on deployment of slots on the 109 and stall

[19//Moach]

https://youtu.be/cIFCQuiZM6Y?t=1028

 

basically, he mentions the slats could pop out under the G forces alone, leading to an accelerated stall on a tight turn - and that this was a notable disadvantage

 

ingame, it seems this effect is not modeled, giving the 109 superior handling on near-stall situations, and an curiously stable onset of stall - which feels like it should much more easily escalate to a dangerous spin if not promptly countered by the pilot

 

it has also been accounted that the slats could also deploy asymmetrically - as there was no connection between each side [citation needed]

 

this bears out with my own recollection of how the 109 performed in IL2 1946 (and in the original IL2 - and CloD too) - in which there was a constant sense of "flying on a thin edge" anywhere below 300km/h

 

 

the BOS model of the 109, is unusually stable on stalls - in my account from the previous titles, it felt very much like the current BOS model of the P40 in that sense, where a low-altitude stall is almost certainly fatal

 

thus it felt like the 109 would almost never "simply stall", and instead would always spin (often violently) - except maybe in ideal controlled conditions, such as when done intentionally

 

 

therefore, it is recommended that the G-induced slat deployment effect (including possible asymmetrical opening) and the resulting sharpness of stall onset are more closely reviewed under such conditions, so that the infamous 109 spins are correctly depicted

Edited October 29, 2016 by Moach

[CisTer-dB-]

I think he mean the Slats  

 

A leading edge slot is a fixed (non-closing) gap behind the wing’s leading edge. 

Aerodynamically, slats work in the same way as fixed slots but slats can be retracted at higher speeds when they are not needed.

Edited October 29, 2016 by ATAG_dB

[19//Moach]

yes - I'd say they're slats too - but on the video he seems to have called it "slots" not sure why... maybe the german accent?

 

 

I've edited the post for (pedantic) correctness... 

 

 

this does not affect the value of what he's pointing out though - that the slAts on the 109 would be forced open by high G forces, causing an accelerated stall

Edited October 29, 2016 by Moach

[unreasonable]

You might want to take a look at this thread if you have not seen it before - 

 

http://forum.il2sturmovik.com/topic/15853-bf109-leading-edge-slats/

 

They could cause a lot of things - asymetrical behaviour, buffeting etc which might have been horrible for the pilots - but not an accelerated stall, since the open slats increase the wing's critical AoA.

Edited October 29, 2016 by unreasonable

[Crump]

Look out the window when you climb an La-5 in bos....

 

The slats deploy as needed and do not provide more than the lift required.  The "snatching" is the movement of the critical Reynolds Number resulting in the aileron adjustment to the new conditions.  It is harmless but the uncommanded movement of the stick can be disconcerting to those not used to it.  Think of it like a trim tab adjusting to the new point of trim only it is a hinged aileron that just moves and since the stick is attached to it, the stick moves too.

 

It will spoil your aim if you are trying to keep the airplane traveling at a fixed position and attitude by keeping your gunsight aligned with a target.  It is no different than configuring the aircraft with gear and flaps after catching the glideslope.  If you do that then you will have to manually adjust (hand-fly) the aircraft's position on the glideslope or listen to "George's" (autopilot) trim clicker firing in rapid succession as he tries to keep the aircraft on the same path.

[Wulf]

Eric Brown comments unfavourably on the slats in his review of the Bf 109 G 6.  He notes that they would often deploy asymetrically, during maneuvering or when  close to stalling speed and that this would often give rise to aileron snatching.  He also states that they had a habit of deploying when passing through the slipstream of another aircraft and that this resulted in profound aiming issues.

 

As has already noted by others,  behaviour of this nature doesn't appear to trouble the in-game 109s. 

Edited October 30, 2016 by Wulf

[E69_geramos109]

You really have aiming isues in game if you pull hard the stick and also spins. A yak is a lot more smoother in the hard turns. I also read some pilots reports when they fought against the yak 3 and they told how the yaks went in spins when they try to follow the 109s at hight speeds and thats thanks to the slats. Of your plane starts to shake but you keep flying

Asimetrical deploying is not a problem is the oposite, in a turn the lift in the wings is not the same and a wing enters in the stall at first than the other. So it should be normal that one slat goes after the other.

Of corse you have aiming isues if the slat opens in a turn but this is better than to enter in a spin when you exced the angle of attack so...

 

I have a gun cam video in witch in the second kill i pull hard the stick to follow a yak. You can see there the trouble i have to control the plane and to evade the spin so.

I think in the game the 109 is really unestable at slow speeds but if you know how to conpensate some effects with torque and rudder you can push the 109 to the limit and make really tight vertical manoubers at slow speeds as i hear in pilot reports so for me is not bad modelled in that aspect. When i fly red i have also a lot of wins on the deck only because the enemy 109 can not controll his plane on my magical yak flap speed so...

For me is more strange how the yak keeps in the air at no speed without spining without slats

Edited October 30, 2016 by E69_geramos109

[Crump]

 

 

as Yak-3 had even better turning capabilities than the earlier versions.

 

The Yak-3 are not a lightly wing loaded aircraft.  They have very small wing area compared to other designs.  You have to run the math on each of them.  

 

The Yak-3 does not turn well making small circles at low airspeed.  It does have a very high sustainable load factor and realizes its best turn performance at a higher speed than most World War II fighters.  In fact, it is probably at the top of the pile for World War II fighters.

 

I would not be surprised if the late war Bf-109 and FW-190's could turn smaller circles at lower speeds than the Yak-3.

[Crump]

I'm afraid that you are mistaken crump; Yak-3 turned extremely well at low speeds with a 360 turn taking a mere 17~seconds. The only other Yak variant that could turn tighter was the Yak-1M from which the Yak-3 was developed.

 

Late war 109s and 190s don't stand a chance in a turning contest. Not even close. Check your sources man. For perspective: None of the E, F, G models currently in the game could turn inside a Yak-3.

 

 

You did not understand what I said.

The P-40 for example can turn smaller circles at lower airspeeds than the Bf-109F4.  The Bf-109F4 can certainly turn fight a P-40 and win if he sticks to his best turn performance speeds.

[MiloMorai]

Fw190A-8

Wing Loading: 241 kg/m² (49.4 lb/ft²)

 

Yak 3

Wing Loading: 181 kg/m² (36.7 lb/ft²)

 

 

[Crump]

Well after interviewing Oskar Bösch about the details of his last victory credit of a Yak 3 I ran an aerodynamic analysis of the FW-190A8 and the Yak 3.  Oskar told me he won that dogfight in a low speed turning contest in which he outturned the Yak.  They ultimately collided as the Yak tried to evade Oskar's guns.

 

 

 

18 24.4.1945 - Yak-3 14./JG 3

 

http://www.luftwaffe.cz/bosch.html

 

 

 

In the last days of the Reich over Berlin Oskar Bösch also survived a mid-air collision with a Russian Yak fighter on 24 April 1945, was captured by the Russians, escaped three days later, and walked over 1,000 km home to Austria with severe injury to his knee.

 

http://argunners.com/story-of-oskar-bosch-former-luftwaffe-ace-with-18-victories/

 

Ultimately, I spoke with Oskar on three seperate occasions about this particular fight just to make sure I got the details right.

 

When the I ran the numbers, to my surprise, the story Oskar relates exactly fits the physics.

 

Aerodynamic data used in the analysis:

 

Yak-3:

 

weight 5935 Power 1210 Level speed 306 Propeller efficiency 0.85 Wing area 159.8 wing efficiency 0.85 Aspect Ratio 5.7

 

FW-190A8:

 

weight 9414 Power 2100 Level speed 326 Propeller efficiency 0.85 Wing area 197 wing efficiency 0.85 Aspect Ratio 6.08

 

 

 

[E69_geramos109]

Of course Yak is more stable in tight turns, it has bigger wings, taller tailfin and thus better overall stability, as it should. I have to say that I'm skeptical about that anecdote, as Yak-3 had even better turning capabilities than the earlier versions. And what makes that anecdote even more suspicious is the fact that 109s had really poor elevator authority at high speeds but Yaks on the other hand retained elevator control much better. It is true, however, that 109 has faster initial turn rate at low to medium speeds, but not at high speeds, thanks to slats, but only for a couple seconds. If the 109 jock continues his turn, he is going to get out-turned by a Yak. So I can imagine some unexperienced Yak pilots getting too excited and executing a stick-to-the-dick maneuver and spinning out of control, when they only would have needed to lag pursuit the 109 for the initial turn.

 

First off, Yak's flaps issue was fixed 3 nerf patches ago, so they are not a problem anymore. You get a lot of victories, not because the FM is wrong but because those 109 pilots should not be down on the deck trying to mix it with a Yak. It is a fact that Yak-1 is more maneuverable than 109s. On the other hand if the 109 pilot is disciplined and uses his superior climb and speed, there's nothing the Yak-1 pilot can do, 109 can always get above the Yak and just yo-yo him to death.

 

Yak-1 has lower stall speed than 109, as it should. So it shouldn't be too hard to connect the dots. I'll still do it for you= Yak-1 can fly at speeds where 109 simply falls out of the sky. And finally, just because 109 has slats doesn't mean that no other aircraft can have lower stall speed. Nothing magical about that. It's high school physics.

What i mean is that i know yak can make a tight turn but is is not true that the 109 is easyer. When im in the 109 not a lot of people spin in close combat, but when im in the yak a lot more people can not control the 109. Here is what people is complainig, that the slats are bad modelled but i dont think so. In the game they dont allow you to turn inside a yak. They only advise you and keep you a little more in the air but to fly there requires some skill to aim and to change direction rolling thats all. and allso the drag when they deploy makes you to lose a lot of energy

 

Slats also help in this exited pilots who pull hard the stik. In any plane without slats is easy to spin if yu pull the stick too much, but in a plane with slats they deploy and keep the plane there. Maybe that is why 109 pilot report this from yaks3. A 109 should turn really good betwen 400 and 500 and maybe if they pull hard the stick at those speeds is hard for a plane to follow them. Remember that to have a lower wing load is good at slow speeds not at high. Thats why 109, 190, P51, P47 were more manoubrable at some speeds and if they keep his optimal speed to turn they can turnfight with more slow manoubrable planes 

Edited October 31, 2016 by E69_geramos109

[Dakpilot]

Well after interviewing Oskar Bösch about the details of his last victory credit of a Yak 3 I ran an aerodynamic analysis of the FW-190A8 and the Yak 3.  Oskar told me he won that dogfight in a low speed turning contest in which he outturned the Yak.  They ultimately collided as the Yak tried to evade Oskar's guns.

 

 

http://www.luftwaffe.cz/bosch.html

 

 

http://argunners.com/story-of-oskar-bosch-former-luftwaffe-ace-with-18-victories/

 

Ultimately, I spoke with Oskar on three seperate occasions about this particular fight just to make sure I got the details right.

 

When the I ran the numbers, to my surprise, the story Oskar relates exactly fits the physics.

 

Aerodynamic data used in the analysis:

 

Yak-3:

 

weight 5935 Power 1210 Level speed 306 Propeller efficiency 0.85 Wing area 159.8 wing efficiency 0.85 Aspect Ratio 5.7

 

FW-190A8:

 

weight 9414 Power 2100 Level speed 326 Propeller efficiency 0.85 Wing area 197 wing efficiency 0.85 Aspect Ratio 6.08

 

 

What are the power figures

 

1210 HP for Yak -3 and

 

2100 HP for Fw190 A8?

 

Cheers Dakpilot

[III/JG52_Otto_-I-]

Everybody must remember, that Lavochkin La-5 is a Lagg-3 with radial engine installed, La-5 born without automatic slats, but the handling and stability was very poor.
The slats that were fitted on the LaGG-3 from series 35 onwards and from very early on in the La-5 development, in an attempt to matching performances with German Bf-109. but still, they did not full succeed.

If anybody is thinking in nerfing the Bf-109 Slats, don´t forget nerfing the Lagg-3 and La-5 slats too.   

 

 

Edited November 5, 2017 by III/JG52_Otto_-I-

[XQ_Lothar29]

Everybody must remember, that Lavochkin La-5 is a Lagg-3 with radial engine installed, La-5 born without automatic slats, but the handling and stability was very poor.

The slats that were fitted on the LaGG-3 from series 35 onwards and from very early on in the La-5 development, in an attempt to matching performances with German Bf-109. but still, they did not full succeed.

 

If anybody is thinking in nerfing the Bf-109 Slats, don´t forget nerfing the La-5 slats too.   

 

 

+1

[Crump]

 

 

What are the power figures   1210 HP for Yak -3 and   2100 HP for Fw190 A8?

 

 

I will check those figures.

[Crump]

What are the power figures 1210 HP for Yak -3 and 2100 HP for Fw190 A8? Cheers Dakpilot

 

The Yak 3 power was wrong as I was told the wrong engine.  It should be 1500hp.  it does not alter the conclusion of the analysis.  Oskar would have been able to turn with and shoot down the Yak 3 under the conditions of the fight.  The Yak 3 performance is lift limited and not thrust limited if he matched speeds with Oskar's aircraft.

 

The FW-190A8 is correct and represents a BMW801S series equipped aircraft out of 14/JG-3.

Edited November 1, 2016 by Crump

[Brano]

1500hp? That must be VK-107A of Yak-9U. VK-105PF-2 of Yak-3 had 1240hp at 2100m.

So which Yak is in your story? Make up your mind.

[Crump]

How about pounding sand if you are going to be an impatient jerk. Data and constructive conversation is appreciated. I made the analysis for myself years ago and not for you today.

Edited November 2, 2016 by Crump

[Brano]

Thanks for not answering my question. Will not bother with this anymore.Just don't confuse other people with incorrect datas.

[Crump]

The make up ypur mind comment overshadowed any question.

[novicebutdeadly]

https://youtu.be/cIFCQuiZM6Y?t=1028

 

basically, he mentions the slats could pop out under the G forces alone, leading to an accelerated stall on a tight turn - and that this was a notable disadvantage

 

ingame, it seems this effect is not modeled, giving the 109 superior handling on near-stall situations, and an curiously stable onset of stall - which feels like it should much more easily escalate to a dangerous spin if not promptly countered by the pilot

 

it has also been accounted that the slats could also deploy asymmetrically - as there was no connection between each side [citation needed]

 

this bears out with my own recollection of how the 109 performed in IL2 1946 (and in the original IL2 - and CloD too) - in which there was a constant sense of "flying on a thin edge" anywhere below 300km/h

 

 

the BOS model of the 109, is unusually stable on stalls - in my account from the previous titles, it felt very much like the current BOS model of the P40 in that sense, where a low-altitude stall is almost certainly fatal

 

thus it felt like the 109 would almost never "simply stall", and instead would always spin (often violently) - except maybe in ideal controlled conditions, such as when done intentionally

 

 

therefore, it is recommended that the G-induced slat deployment effect (including possible asymmetrical opening) and the resulting sharpness of stall onset are more closely reviewed under such conditions, so that the infamous 109 spins are correctly depicted

 

Back on topic.....

 

 

In regards to the 109 performance in BOS/BOM v's other titles, from what I have read in regards to the stall/spin characteristics of the 109, this title is the closest.

 

One of the reasons that the 109 was selected rather than the he112 was the superior stall/spin recovery of the aircraft, and from memory one of the reasons was the airfoil that was chosen in that it was forgiving (Crump please don't shoot me if what I read was incorrect...)

 

Whilst the wing was changed after the "E series, I think it's reasonable to assume that good stall/spin recovery was still part of the design

 

 

In regards to the slats,

 

The asymmetrical deployment was a problem with the 109E series, and later ones that were not adjusted properly because the design was changed to solve asymmetrical deployment.

 

 

[Crump]

 

 

In regards to the 109 performance in BOS/BOM v's other titles, from what I have read in regards to the stall/spin characteristics of the 109, this title is the closest. One of the reasons that the 109 was selected rather than the he112 was the superior stall/spin recovery of the aircraft, and from memory one of the reasons was the airfoil that was chosen in that it was forgiving (Crump please don't shoot me if what I read was incorrect...) Whilst the wing was changed after the "E series, I think it's reasonable to assume that good stall/spin recovery was still part of the design In regards to the slats,   The asymmetrical deployment was a problem with the 109E series, and later ones that were not adjusted properly because the design was changed to solve asymmetrical deployment.

 

You got it!  

 

The Bf-109 has a normal stall with the added benefit of being spin resistant as is any slat equipped aircraft.  

[NZTyphoon]

1500hp? That must be VK-107A of Yak-9U. VK-105PF-2 of Yak-3 had 1240hp at 2100m.

So which Yak is in your story? Make up your mind.

Brano is dead right, the Yak 3 was powered by the Klimov VK-105PF-2 that was rated at 1,250hp @ take-off/ 1,240hp @ 2,100m (source: Gordon, Komissarov and Kommisarov).

 

 

The Yak 3 with the 1,500hp VK-107A  was essentially a post-European war aircraft:

 

[Crump]

Brano is dead right, the Yak 3 was powered by the Klimov VK-105PF-2 that was rated at 1,250hp @ take-off/ 1,240hp @ 2,100m (source: Gordon, Komissarov and Kommisarov).

 

 

And?  If Brano bothered to read the thread, he would see that Dakpilot questioned the power settings.  I looked into it and there are other variants of the Yak-3 or aircraft that could very well pass for a Yak 3 when you are a Luftwaffe pilot in 1945 engaged in a close quarter turning fight.

 

It did not change the analysis and the one done with the 1200 hp still holds for the basic relative performance in answering the question, "Was it possible or a fluke for Oskar to have out-turned a Yak 3 for his last victory in World War II?"

 

In other words, please read the thread and stop concentrating so much on following me around trying to cause controversy.

 

Thanks You!!

[Crump]

 

 

When the I ran the numbers, to my surprise, the story Oskar relates exactly fits the physics.   Aerodynamic data used in the analysis:   Yak-3:   weight 5935 Power 1210 Level speed 306 Propeller efficiency 0.85 Wing area 159.8 wing efficiency 0.85 Aspect Ratio 5.7   FW-190A8:   weight 9414 Power 2100 Level speed 326 Propeller efficiency 0.85 Wing area 197 wing efficiency 0.85 Aspect Ratio 6.08  

 

I just realized the read and yellow are reversed on the analysis.  The labels are correct and the analysis holds correct but the FW190 is the red lines on one chart and yellow on the other.

 

Makes it hard to read. 

[19//Moach]

stay on topic PLEASE - this thread is not about the yak!

 

 

back on the main point - while the slats were indeed designed to improve high AoA performance, thus lowering the stall speed - what Gunther Rall points out is that they were prone to deploy not as per design, but forcibly under high G forces

 

in such a case, the slats would come out in conditions where they're normally meant to stay retracted (wasn't there a lock switch too?) 

 

obviously enough, this would cause a noticeable change on aircraft behavior towards "strange" - if not leading to loss of control from the unexpected reaction (most WW2 pilots were "noobs" by this community's standards - life doesn't give you the chance to learn from mistakes that end it)

[Askania]

 

VK-105PF2

 

SL - 1290 hp

 

200 m - 1310 hp (1st speed)

 

2100 m - 1240 hp (2nd speed)

 

[novicebutdeadly]

stay on topic PLEASE - this thread is not about the yak!

 

 

back on the main point - while the slats were indeed designed to improve high AoA performance, thus lowering the stall speed - what Gunther Rall points out is that they were prone to deploy not as per design, but forcibly under high G forces

 

in such a case, the slats would come out in conditions where they're normally meant to stay retracted (wasn't there a lock switch too?) 

 

obviously enough, this would cause a noticeable change on aircraft behavior towards "strange" - if not leading to loss of control from the unexpected reaction (most WW2 pilots were "noobs" by this community's standards - life doesn't give you the chance to learn from mistakes that end it)

 

 

Back on topic.....

 

 

In regards to the 109 performance in BOS/BOM v's other titles, from what I have read in regards to the stall/spin characteristics of the 109, this title is the closest.

 

One of the reasons that the 109 was selected rather than the he112 was the superior stall/spin recovery of the aircraft, and from memory one of the reasons was the airfoil that was chosen in that it was forgiving (Crump please don't shoot me if what I read was incorrect...)

 

Whilst the wing was changed after the "E series, I think it's reasonable to assume that good stall/spin recovery was still part of the design

 

 

In regards to the slats,

 

The asymmetrical deployment was a problem with the 109E series, and later ones that were not adjusted properly because the design was changed to solve asymmetrical deployment.

 

 

One of the problems addressed with the new wing design of the F series was the problem of asymmetrical slat deployment in the "E" series.

 

The slat was of a different design, which when adjusted correctly would not deploy asymmetrically,  from the top of my head, it was "fiddly" in that the adjustment needed to be precise (again from memory there were quality issues in regards to these from factory, which required a futher adjustment at the airfield even on a brand new aircraft).

 

The slats were entirely automatic (in that it was the air pushing against them that caused them to either stay in or to come out), so no switch to keep them retracted.

 

 

For those who wonder about the extent of the wing re-design from the E to the F series (quoted from wiki to save me re-writing what I have and it gives a bit more info figures wise, though I did add to it in bold):

 

 

"The entire wing was redesigned, the most obvious change being the new quasi-elliptical wingtips, and the slight reduction of the aerodynamic area to 16.05 m² (172.76 ft²). Other features of the redesigned wings included new leading edge slats, which were slightly shorter but had a slightly increased chord (and different sliding mechanism to address the asymmetrical deployment problme that was in the E series); and new rounded, removable wingtips which changed the planview of the wings and increased the span slightly over that of the E-series. Frise-type ailerons replaced the plain ailerons of the previous models (which apparently eliminated adverse yaw with roll, reducing rudder input in turns which helped to improve turn rate). The 2R₁ profile was used with a thickness-to-chord ratio of 14.2% at the root reducing to 11.35% at the last rib. As before, dihedral was 6.53°.

 

The wing radiators were shallower and set farther back on the wing. A new cooling system was introduced; this system was automatically regulated by a thermostat with interconnected variable position inlet and outlet flaps that would balance the lowest drag possible with the most efficient cooling. A new radiator, shallower but wider than that fitted to the E was developed. A boundary layer duct allowed continual airflow to pass through the airfoil above the radiator ducting and exit from the trailing edge of the upper split flap. The lower split flap was mechanically linked to the central "main" flap, while the upper split flap and forward bath lip position were regulated via a thermostatic valve which automatically positioned the flaps for maximum cooling effectiveness.

From further reading, for the G series onwards (as this feature was from factory, not a limited numbers kit in the F series) if only one radiator is damaged the aircraft shouldn't loose all the coolant as they had shut off/ isolation valves for each radiator.

Edited November 4, 2016 by novicebutdeadly

[Arsenal53]

From http://www.virtualpilots.fi/feature/articles/109myths/ Stalling the 109

"Me 109 E:

"The airplane was equipped with a 60 foot trailing static head and a swiveling pitot head. Although, as may be imagined, operation of a trailing static from a single-seater with a rather cramped cockpit is a difficult job, the pilot brought back the following results:

Lowering the ailerons and flaps thus increases CL max of 0.5. This is roughly the value which would be expected from the installation. Behaviour at the stall. The airplane was put through the full official tests. The results may be summarized by saying that the stalling behaviour, flaps up and down, is excellent. Both rudder and ailerons are effective right down to the stall, which is very gentle, the wing only falling about 10 degrees and the nose falling with it. There is no tendency to spin. With flaps up the ailerons snatch while the slats are opening, and there is a buffeting on the ailerons as the stall is approached.. Withs flaps down there is no aileron snatch as the slats open, and no pre-stall aileron buffeting. There is no warning of the stall, flaps down. From the safety viewpoint this is the sold adverse stalling feature; it is largely off-set by the innocuous behaviour at the stall and by the very high degree of fore and aft stability on the approach glide.

It is important to bear in mind that minimum radii of turn are obtained by going as near to the stall as possible. In this respect the Bf.109E scores by its excellent control near the stall and innocuous behaviour at the stall, giving the pilot confidence to get the last ounce out of his airplanes turning performance."

- RAF Royal Aircraft Establishment (RAE) Farnborough handling trials,Bf.109E Wn: 1304. M.B. Morgan and R. Smelt of the RAE, 1944.

Me 109 E-4:

"I was amazed at how docile the aircraft was and how difficult it was to depart, particularly from manoeuvre - in a level turn there was lots of warning from a wide buffet margin and the aircraft would not depart unless it was out of balance. Once departted the aircraft was recovered easily by centralizing the controls."

- Charlie Brown, RAF Flying Instructor, test flight of restored Me 109 E-4 WN 3579. Source: Warbirds Journal issue 50.

Me 109 G:

"- How the Messerschmitt reacted to hard pull? Did she stall?

There is the general opinion that you could not make her stall by pulling but she could 'slip'."

- Kyösti Karhila, Finnish fighter ace. 32 victories. Source: Interview by Finnish Virtual Pilots Association."

 

another quote:

 

"Me 109 E:

"The Bf 109s also had leading edge slats. When the 109 was flown, advertently or inadvertently, too slow, the slats shot forward out of the wing, sometimes with a loud bang which could be heard above the noise of the engine. Many times the slats coming out frightenened young pilots when they flew the Bf 109 for the first time in combat. One often flew near the stalling speed in combat, not only when flying straight and level but especially when turning and climbing. Sometimes the slats would suddenly fly out with a bang as if one had been hit, especially when one had throttled back to bank steeply. Indeed many fresh young pilots thought they were pulling very tight turns even when the slats were still closed against the wing. For us, the more experienced pilots, real manoeuvring only started when the slats were out. For this reason it is possible to find pilots from that period (1940) who will tell you that the Spitfire turned better than the Bf 109. That is not true. I myself had many dogfights with Spitfires and I could always out-turn them.

One had to enter the turn correctly, then open up the engine. It was a matter of feel. When one noticed the speed becoming critical - the aircraft vibrated - one had to ease up a bit, then pull back again, so that in plan the best turn would have looked like an egg or a horizontal ellipse rather than a circle. In this way one could out-turn the Spitfire - and I shot down six of them doing it. This advantage to the Bf 109 soon changed when improved Spitfires were delivered."

- Erwin Leykauf, German fighter pilot, 33 victories. Source: Messerschmitt Bf109 ja Saksan Sotatalous by Hannu Valtonen; Hurricane & Messerschmitt, Chaz Bowyer and Armand Van Ishoven."

(in an interview findable on youtube Closterman says the same thing)

[RAY-EU]

Interesting WW2 histoty reports mention pilot of Bf 109 G2 Mr Väinõ Pokela asked of the top speed of the Me told earlier (it's 720Km/h).

[...] The absolute speed limit is found in dive . I had to do some over 900 Km/h dives . The speeddometer scale ends at 900 , and at that you feel the flutter in the wings . Guess it was very near the top speed , when the plane felt like falling apart ."...[...]