P-51's vs. Me-109's and Fw-190's

[wmaxt]

[quote="Soren"]

Originally Posted by wmaxt

Infact the the 109G was designed for elevator stick forces of up to 85kg !! (Much more than the Spit's stick design)

But remember the British practically didn't test their captured 109's at all, as they would stop any maneuver as soon as the slats popped out, which they did almost immediately in any hard maneuvering.

85kg? 172lbs? Thats more than the P-51 and above average too. That would tire a pilot out in just 3/4 manouvers.

As I said above the British testing may be even more approprate when applied to average or new low time German pilots in '44/'45, even if it didn't show the ultimate performance capabilities.

wmaxt

[FLYBOYJ]

Originally Posted by wmaxt

85kg? 172lbs? Thats more than the P-51 and above average too. That would tire a pilot out in just 3/4 manouvers.

That's really high!

[Soren]

85kg? 172lbs? Thats more than the P-51 and above average too. That would tire a pilot out in just 3/4 manouvers.

You missunderstood me wmaxt..

The 109's stick was designed to 'handle' that much force, meaning it was easier for the pilot. The Spit would have to have a stick which reached the roof to be that effective !

[Soren]

Look at this(Picture below).

For a 1/5 aileron deflection at 400mph the 109E needed 37lb stick force, the Spit-1 needed 57lb. This is a 54% higher stickforce for the Spit pilot. So to build up the same moment like in a 109, the spitfire stick must have been 54% longer, if so it probably would have reached out of the roof window.

[wmaxt]

Originally Posted by Soren

Look at this(Picture below).

For a 1/5 aileron deflection at 400mph the 109E needed 37lb stick force, the Spit-1 needed 57lb. This is a 54% higher stickforce for the Spit pilot. So to build up the same moment like in a 109, the spitfire stick must have been 54% longer, if so it probably would have reached out of the roof window.

The 85kg stick force for elevator is related to what then? 85kg is barely handleable by a weight lifter.

57lbs is still acceptable but very close to the practile limit.

We were talking elevator not aileron, the requirements are different.

The control stick is a lever, moving the pivot would make a large change in a very small move.

The 85kg you gave is for a later aircraft that had changed those perameters, what are the pertinent numbers?

We started with a comparison with the P-51, what's the corralation?

wmaxt

[plan_D]

The Bf-109 didn't give birth to the great aces of World War 2, the great aces of World War 2 made the Bf-109 what it was. The Bf-109 required an expert to fly it at it's full potential, unlike a Mustang or Spitfire.

You keep going on about those slats and how amazing they were but they did scare pilots and they did create sudden yaw. If a pilot is scared of it, he's not going to put it to it's limits. Then the aircraft hasn't got it's potential!

Modern day pilots have the advantage of hindsight. They get people from today, historians, old Luftwaffe pilots etc. etc. telling them not to worry and explaining exactly how it was all done. That's all well and good now but in the 1940s the Luftwaffe were training their pilots to be up there and ready as quick as possible.

Do you honestly believe that if those aces had flown the Fw-190A instead, they wouldn't have achieved their impressive results?

And on a final note, the FAF had some remarkable pilots which did wonders with anything they got their hands on. Of course they're going to like the -109 more...what else did they have? Gladiators, old Mohawks and Buffaloes.

[DerAdlerIstGelandet]

Originally Posted by KraziKanuK

You do know that the Spit had a narrower track than the 109?

What caused the 109 accidents was the toe-in. If it was not set down square and the pilot had a moment of in-attension, the 109 would vere in the direction opposite to the wheel touching. A ground loop would follow with the forces being too great for the strut to bear, so breaking, if the ground loop was severe enough.

I was actually always thinking about that when I looked at design diagrams and dimensions. The Spitfire was the narrower of the two.

[FLYBOYJ]

Originally Posted by Soren

Look at this(Picture below).

For a 1/5 aileron deflection at 400mph the 109E needed 37lb stick force, the Spit-1 needed 57lb. This is a 54% higher stickforce for the Spit pilot. So to build up the same moment like in a 109, the spitfire stick must have been 54% longer, if so it probably would have reached out of the roof window.

This chart deals with aileron force (roll), lighter control forces around one axis. What about elevator and elevator trim position? In a turn the aileron banks the aircraft, the radius of the turn is controlled with elevator back pressure providing the power setting remains the same. Both the -109 and Spit had elevator trim which could greatly relieve back pressure. Are these values assumed with trim in the most favorable position?

[wmaxt]

Originally Posted by FLYBOYJ

This chart deals with aileron force (roll), lighter control forces around one axis. What about elevator and elevator trim position? In a turn the aileron banks the aircraft, the radius of the turn is controlled with elevator back pressure providing the power setting remains the same. Both the -109 and Spit had elevator trim which could greatly relieve back pressure. Are these values assumed with trim in the most favorable position?

Exactly, as I pointed out above we need info relative to why the stick was designed for 85kg force for elevator movement.

wmaxt

[Soren]

The 85kg stick force for elevator is related to what then? 85kg is barely handleable by a weight lifter.

57lbs is still acceptable but very close to the practile limit.

We were talking elevator not aileron, the requirements are different.

The control stick is a lever, moving the pivot would make a large change in a very small move.

The 85kg you gave is for a later aircraft that had changed those perameters, what are the pertinent numbers?

We started with a comparison with the P-51, what's the corralation?

wmaxt

With an average pilot the 109G's stick was designed so it could effectively provide 85kg of force for the elevators, and 70kg for the ailerons.

For a 1/5 deflection at 400mph the "109E" would need only 37lbs stick force, so this would be even lower in the 109G and onwards.

As for the elevator deflection in the 109G an onwards, the stick would need 'much' less force than in the 109E.

[Soren]

Actually the 109F had an improved elevator control over the 109E as-well, and British tests confirm this:

[wmaxt]

Soren,

85kg and 70kg are a lot and would tire a pilot very quickly. Or are you saying a force of an undetermined value will provide 85/70kg of force to the affected eppanage? If so what's that value?

What does this have to do with the tightening of controls at high speed of the P-51/Bf-109G/K relative to one another?

What does an E have to do with this?

I think all we really have is the subjective observations of various pilots. Taken as a whole neither plane becomes totaly uncontrolable even near the airspeed limits of the airframes.

The bottom line is that so far the two planes are very close. Does anyone have some data to change that statement?

wmaxt

[Soren]

Originally Posted by wmaxt

85kg and 70kg are a lot and would tire a pilot very quickly. Or are you saying a force of an undetermined value will provide 85/70kg of force to the affected eppanage?

Yes.

If so what's that value?

Sorry but I don't know that value. What I know is that the new stick design effectively lightened the controls for the pilot at high speeds.

I think all we really have is the subjective observations of various pilots. Taken as a whole neither plane becomes totaly uncontrolable even near the airspeed limits of the airframes.

I agree.

The bottom line is that so far the two planes are very close. Does anyone have some data to change that statement?

Yes I already provided it;

The Bf 109K-4 has a 5lbs (32 kg) lighter lift-loading than the P-51D, plus a better power-loading, wing aspect ratio, Wing CL-max, and a much higher max wing AoA.

All this is enough to prove that the 109 was the better "dogfighter", BUT, not the best overall fighter.

[wmaxt]

No, those stats say it could/should. We still need the actuall numbers produced in the manouvers in question ie how fast does it accelerate, roll, turn, enter an accelerated stall and retain energy. There is often a dissparity between theory and reality.

I've read pilot accounts on both sides that say their plane was better and at least for those pilots that was true or they would not have lived to say it. Or is it only because the Bf-109 is harder to fly at it's max and the average German pilot was to inexperianced to make full use of it?

Right now I see two aircraft that are very close, one has some stats that infer it could/should be better. We have nothing difinitive yet that can tell us it was better or by how much.

wmaxt

[lesofprimus]

All this is enough to prove that the 109 was the better "dogfighter", BUT, not the best overall fighter.

I agree 100%...