Interceptor vs Escort.

[wmaxt]

I agree and disagree with you. At the same time I would want to test the aircaft as found but also I would want to compare it to an aircraft in a similar configuration. So I agree and disagree with you.

No, your right it should be tested both ways. My point was the test was still valid even with the gondolas.

wmaxt

 

[Soren]

The fact that a plane has good stalling characteristics doesn't help you avoid the stall in the first place.

No but if your behind an enemy a/c with a ealier stall, you will be able to follow this a/c without stalling yourself- An Advantage.

And actually I don't really disagree with FJ, as I said its possible the Spitfire gave better warning of the stall, but it also stalled ealier on.

What started this discussion was FJ saying the Spitfire had better stall characteristics than the 109, which it clearly doesnt. But then we got to talk about stall "warning", in which the Spitfire might very well be superior. I just disagree with the first point....

 

[FLYBOYJ]

First off I wasnt specificly talking a high speed stall FJ, so I don't know why wmaxt mentioned this.

Now about the 109 and its stall characteristics...

Messerschmitt put automatic wing-slats on the 'outer' part of the wings. At sufficient AoA, these open, effectively extending the lift vs AoA curve. Basically this means that on the Bf-109, the outer wing sections stall at a considerably higher AoA than the inboard parts of the wing. What does this do? It virtually eliminates the wing-drop of the wing when the wing starts to stall. Plus, it allows full aileron usage up to the point at which the outer part of the wing starts to stall. This leads to a very gentle stall until the wing slats themselves stall.

So the 109 will stall later and much more gently than the Spitfire, but(Assuming the Spitfire atcually had an elliptic wing "Which it didnt") I agree that its final stall warning 'might' not be as pronounced as in the Spitfire, however it is reached much later in the 109. So nontheless the Spitfire doesnt have better stall characteristics than the 109. This is what my point was all about...

Now about the Spitfire's wing, well as I've already said it has a 2 degree twist to it, so the lift distrobution IS NOT elliptical.

Soren, I know that the LE slats do, I've flown aircraft with them, and the slats don't stall, the whole wing does. The Slats change the shape of the wing, increasing the wing area, they're a great device. Just because you stall later (or slower), it doesn't mean anything if you don't know its coming. As shown, the Spit talks to you - its telling you its going to stall - the 109 doesn't do this at the most critical time the aircraft is in the air, at landing! A 2nd Lt. Eliminator! Besides even with the slats both aircraft carry very similar stall speeds!

The tests posted show the data, sure the LE slats help, but they also hurt as well. I'll rephrase my comment from yesterday - good aircraft stall characteristics? 1. - 25% stall warning, 2 - 25% knowing what the aircraft is going to do when it stalls and 3 - 50% winding up in a desired attitude after the stall.

Well then we agree.... the Spitfire didnt have better overall stall characteristics than the 109.

Upon landing the Spit's stall characteristics were better, but in a dogfight the 109's were better. (Not that the Spit's werent good)

Now as far as aerodynamics on the Spit's wing - we could discuss this all day if its really elliptical aerodynamically, but the bottom line, it carries the shape, the tips stall earlier than a rectangular wing and that's my point.

FJ there's nothing to discuss about the Spit's wing being Elliptical or not, cause it simply wasnt. The "Wash-out" was there to help the wing the same way the 109's slats did(although not as effectively), but at the same time it ruined the microscopic advantage of the elliptical shape.

As seen by the posted pilot reports, both aircraft stall well, but with the -109 giving no stall indication when its dirty, well that's an accident waiting to happen and apparently it did on many occasions!

Yes because of the landing gear. Other than that pilots quote the 109 as very predictable, and stalls were very gentle.

Nope - we're going to agree to disagree. From the information gathered as a pilot, I would have reservations about an aircraft that gave no stall warning when dirty. True, the slats help, but I could tell you in a power on or departure stall, the wing will drop without opposite rudder, slats or not, this due to "P" factor.

My personnel opinion on this is the Spitfire will stall "better" (early stall warning, stall perdictability, and a recoverable attitude after stall). I don't believe the -109 meets all of these and again this is apparent in the -109 vs Spitfire turning discussion. The only way to really prove this is to go out and fly em. You know anyone with a spare Spitfire and -109?

 

[Soren]

So overall you think the Spit has a 25% advantage in stall characteristics because of its stall warning ?

In almost every other area the 109 is superior, it stalls later, more gently, and recovers equally well...

Charlie Brown on the 109E-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."

 

[FLYBOYJ]

So overall you think the Spit has a 25% advantage in stall characteristics because of its stall warning ?

ABSOLUTELY! - There is nothing worse than being in an aircraft doing departure or power on stalls and not knowing when the break is going to happen! Could imagine this in combat! It's no wonder why the Spit was argumentatively believed to be superior in a turn! I also believe this, compiled with a narrow track landing gear is what attributed to the -109s high accident rate.

it stalls later, more gently, and recovers equally well...

Later? yes, not by much - don't make it better except on landing, Gently? I think they're the same, Recovery? the same. The Spit gives stall warning about 10-15 knots before the stall- perfect!

 

[DerAdlerIstGelandet]

Well here is my question. In the stuff you posted up there FJ about the stall warnings, 2 said that there were no stall warnings at all and one said you got a nice buzz in the stick. So could this mean that unless you knew what to look for you would know the aircraft is about to stall however if you knew what to look for the stall warning was there and quite good? Just a theory since that would explain how German pilots enjoyed flying the aircraft and got the best out of it and the British did not. They simply did not know the aircraft.

 

[FLYBOYJ]

Well here is my question. In the stuff you posted up there FJ about the stall warnings, 2 said that there were no stall warnings at all and one said you got a nice buzz in the stick. So could this mean that unless you knew what to look for you would know the aircraft is about to stall however if you knew what to look for the stall warning was there and quite good? Just a theory since that would explain how German pilots enjoyed flying the aircraft and got the best out of it and the British did not. They simply did not know the aircraft.

You want an aircraft to give you stall warning about 10 knots before the stall, probably 15 knots for a high performance aircraft. Both -109 and Spitfire did this well however it seems the Spitfire gave earlier stall warning. The 109 gave no warning when it was dirty, gear down, flaps down. This is very bad as when you're landing where you normally carry an airspeed just a few knots above stall speed. Combine the narrow landing gear on the 109 and throw in a green pilot and you have an accident waiting to happen......

There has always been the argument of the 109 being able to turn with the Spit. I believe that the un-nerving opening of the 109s slats perhaps combined with late stall warning during tight turns probably gave rise to this scenario. I believe the more experienced 109 pilots eventually learned when the break would exactly happen based on bank angle, AOA and airspeed.

My final comments in this discussion is even with the LE slats, both aircraft gave very similar stall performace. In most cases the 109 had a slightly lower stall speed but it seems this was not an advantage when compared to the earlier stall warning characteristics of the Spit.

 

[Glider]

In this debate I have found the following that may be of interest.
Yugoslavia had both 109E's and Hurricanes in its airforce when Germany attacked. Before the war started the 109 had a much heavier accident rate, so much so that new pilots converting from the Fury started on the Hurricane before moving on to the 109 via a training session in the 108.
The accident rate was according to them due to the narrow track undercarriage (no surprise there) and the variable pitch prop. In the article they didn't mention the stall.

 

[FLYBOYJ]

The accident rate was according to them due to the narrow track undercarriage (no surprise there) and the variable pitch prop. In the article they didn't mention the stall.

What I would surmise is the narrow track landing gear gave problems during landing, especially in a crosswind. Combine this with carrying a few extra knots on landing and it makes sense.

It interesting that they mentioned the variable pitch propeller. It's an extra task but usually a variable pitch prop is pretty simple to operate.

 

[Soren]

FJ,

Did you read my quote on the E-4 ?

Note this part: "in a level turn there was lots of warning from a wide buffet margin"

So the 109 does infact warn the pilot of the stall, but 'maybe' not as early on as in the Spitfire.

All in all I think the two fighters were very much equal in combat, with the Bf-109 having the advantage of stalling later and being able to achieve higher angles of attack, while the Spitfire would warn its pilot a little sooner of the stall.

One thing is for sure though, they were both excellent fighters, the best of their breed....

 

[FLYBOYJ]

Agree

 

[Soren]

Glad to hear it

 

[DerAdlerIstGelandet]

I agree also.

FJ I was not attacking you with my post up there I was just wondering your thoughts on it.

 

[FLYBOYJ]

I agree also.

FJ I was not attacking you with my post up there I was just wondering your thoughts on it.

Hey no sweat Adler

 

[KraziKanuK]

What I would surmise is the narrow track landing gear gave problems during landing, especially in a crosswind. Combine this with carrying a few extra knots on landing and it makes sense.

The Spitfire had a narrower track than the 109. The Russians did not use the Spit as a front line fighter partly because of its weak gear and nose heaviness.

What gave problems to the 109 was the toe in the wheels had. If the landing was not 'square' (wings level) then the a/c would begin a ground loop (to the opposite direction of the wheel touching) and if not caught in time would put too much stress on the leg and it would collapse.

An old Spit pilot once told me that a flick stall in a Spit could be very deadly > almost impossible to get out of the resulting spin.

 

[FLYBOYJ]

What I would surmise is the narrow track landing gear gave problems during landing, especially in a crosswind. Combine this with carrying a few extra knots on landing and it makes sense.

The Spitfire had a narrower track than the 109. The Russians did not use the Spit as a front line fighter partly because of its weak gear and nose heaviness.

What gave problems to the 109 was the toe in the wheels had. If the landing was not 'square' (wings level) then the a/c would begin a ground loop (to the opposite direction of the wheel touching) and if not caught in time would put too much stress on the leg and it would collapse.

I believe the -109 had a seamless tube oleo, light but not too strong. I also believe the -109s landing gear were "toe out, camber in" potentially causing a "wheell barrel" effect if one tire contacts the runway first further adding to the problem.

An old Spit pilot once told me that a flick stall in a Spit could be very deadly > almost impossible to get out of the resulting spin.

A "flick stall" is similar to a snap roll except you're flying at a lower power setting and is very susceptible to spin entry in any high-torque, high power aircraft, especially at a low propeller pitch setting. I don't see doing this in combat unless you're caught by surprise at a low-cruise power setting and you want to confuse your opponent who by now is filling your aircraft full of cannon shells (providing you're flying a Spit). If you attempt this maneuver too tightly, not only will you spin but you could easily over-stress the airframe. If you spin you need to immediately come back to idle power and apply opposite rudder and forward stick before you allow the aircraft to get too "wound up."

I would suspect a Mustang would be real susceptible to this especially with its fuselage fuel tank full of fuel.

 

[DerAdlerIstGelandet]

I believe the -109 had a seamless tube oleo, light but not too strong. I also believe the -109s landing gear were "toe out, camber in" potentially causing a "wheell barrel" effect if one tire contacts the runway first further adding to the problem.

I think you are correct.

 

[vanir]

WRT the OP and K4 vs Mustang, I've just been watching some war footage of the allied bombing campaign prior to the introduction of P51 escorts (a fatality rate of 8+% for US bomber crews, or less than 13 mission survivability), in which 109's massed to intercept bomber flights and were followed by 110's which really carved them up with rockets.
At this time the Luftwaffe were enjoying an 8:1 kill ratio against RAF fighters that tried to cross the channel, btw.
Even so, during some missions every single Luftwaffe fighter would have as many as 540 machineguns trained on them each pass by the bombers overlapping cover zones. It is considered their effort and that of their industry to rebuild was phenominal.
But it was becoming a war of attrition and the Luftwaffe were quickly running out of experienced pilots.

When Mustangs came with the bombers, they attacked the German fighters while they were still massing, and made mince meat of pursuing 110's. This changed the bombing campaign through 1943 into one in which the allies gained total air superiority.

So by the time magnificent aircraft like the K4 made it to squadron service, you had pilots who were still pimpled and anxious about dating girls.
There were so many allied aircraft flying over Germany at this time,
"fighter bombers often had to wait in line to attack targets."
-Wings of War documentary.

I think while the Mustang's appearance can not be understated, I'd agree that its performance as a contemporary dogfighter may be somewhat a little overrated.

 

[FLYBOYJ]

some missions every single Luftwaffe fighter would have as many as 540 machineguns trained on them each pass by the bombers overlapping cover zones.

This is a point sometimes missed in some of the fourms here. There was an element of teamwork between the gunners within the cover zones and as we know thee zones were effictive but not absolute in defence of the bomber formations.

 

[wmaxt]

Another thing often missed is that before escorts the loss rate was ~9/10% per mission of which the AAA acounted for the first 3/4%. In late '43 P-38s were used and the loss rate immediately dropped to 4/5%. Many times the attacking fighters would by pass the groups with P-38 escort to go after the unescorted bombers - in other words the escort was still effective even when they didn't get into a fight. Escort was the key not so much which airplane was doing the escorting.

wmaxt