Spit/109 sea level speed comparisons in 1.08 beta patch

[Kurfürst]

Originally Posted by MiG-3U

Hm... using the same standars there is no real test data supporting 109E doing 500kmh at sea level.

Of course there it is.

Only a calculation based on a prototype aircraft with a non-standard two speed supercharger and a power value which is higher than normal 601 power.

I call BS on this. Got any sources for these claims?

However, there is several test data sets supporting speeds around 470kmh for 1.3ata and supposedly faster 109F is doing just 495kmh at same power according to kenblat.

I would like to see them. Hopefully, they are just as detailed as the flight tests and official specs you are dismissing. That includes calibration curves for the pitot, boost and speed measured at various altitudes and known conditions, and proof check of the engine at a bench.

[Glider]

Originally Posted by Robo.

I agree in general except for the fact (major flow I would say) that the Emil will slow down rather fast in this sustained horizontal turn. Spitfire will win in RL situation described by you, because the pilot would obviously not try to sustain these 400kph, he will try to bear his guns on the 109 and will do so rather soon. No matter what you do in a 109, if you chose to remain horizontal, the only way of evading the Spitfire would be flying straight. And flying straight is not sustained turn. See?

I do find this theory that the 109 will be able to turn better than a SPit at higher speeds a little foolish.

a) There are no, repeat no tests, from any side that support this theory.
b) The 109 locked up faster than a spitfire at higher speeds so the spit will have all the advantages getting into the turn by which time the 109 will be in the smelly stuff
c) You quickly lose speed in a turn which will nulify any theoretical advantages
d) The above description of what will happen shows the folly of this theory
e) The 12 boost throws the theory out anyway as it passes the power to weight ratio advantage to the SPitfire
f) Its worth remembering what the German test establishment said about the turning ability of these aircraft:-

Before turning fights with the Bf 109 E type, it must be noted in every case, that
all three foreign planes have significantly smaller turning circles and turning times.
An attack on the opponent as well as disengagement can only be accomplished on the basis of
existing superiority in performance.

Notice it doesn't say:-
a) The SPitfire is better at slow speeds
b) That the 109 can turn inside the Spitfire at high speeds
c) Ensure you keep your speed up against the Spitfire in a turning fight

It says basically DON'T GET INTO A TURNING FIGHT.

Can someone explain how the German test establishment got it so wrong.
After all they only had the real aircraft, real pilots to fly mock combats who obviously were very up to date on the Me109, amongst the finest engineers and designers in the world, people both well versed in the theory and experienced in this field, plus the resources of a test establishment.
I repeat the question, how did they get it so wrong?

[MiG-3U]

Originally Posted by Kurfürst

Of course there it is.

Please post.

Originally Posted by Kurfürst

I call BS on this. Got any sources for these claims?

V15 chart on your site shows clearly two speed supercharger and text sites höhen and bodenlader, power value in the calculation is 1018ps vs 990ps for Db601A.

All at your site including 109F kenblat.

[Robo.]

Originally Posted by Glider

I do find this theory that the 109 will be able to turn better than a SPit at higher speeds a little foolish.

Oh yes, 109 could indeed turn tighter than a Spitfire at speeds around and above 400 kph.

In reality this was not very relevant in pure horizontal turnfight for the reasons you named. It was great advantage at BnZ maneuvring, even turning with a Spitfire that is breaking away from your attack - you can turn long enough to score nice deflection shot on him. But that is not anywhere close to sustained turn, you do a a 1/8 of a turn and away you break. If you stayed at that turn, you would burn your E and you would end up with a very angry Spitfire on your tail very soon.

[Kurfürst]

[QUOTE=MiG-3U;463981]Please post.

Here.

Flight test.



Guranteed specs.



I would like to see similiar detailed specs for the Spitfire. At +12 lbs boost. Calibration curves, engine bench test, detailed description of airframe conditions and temperature conditions.

None such exists...

V15 chart on your site shows clearly two speed supercharger

Nope.

and text sites höhen and bodenlader,

Yes. And?

power value in the calculation is 1018ps vs 990ps for Db601A.

And have the DB 601Aa (not the DB 601A) in the sim, which had 1045 PS (1175 PS WEP) anyway. So the tested example had to reached 498 kph at 1018 PS. We have an 1045 PS variant. Are you saying that it should be even faster..?

Now, care to tell me, that regardless of the supercharger design, that what is wrong with the test, since the plane has about the same power our plane in the sim has.

All at your site.

Nope.

I also have similiar curves for G-14, G-6, G-1 etc. on my site. It only shows that the DB 60x supercharger could be run at will at fixed speeds as well. It's no witchcraft, all that is needed to override the barometric control of the hydraulic coupling. Which they did often during these tests, see some of the G-6 and G-14 tests:

http://kurfurst.org/Performance_test...44_trials.html

Besides the actual supercharger operation is completely irrelevant. We KNOW for a fact that the plane had 951 PS in high speed flight (about 50-60 PS down on power) and reached 493 kph with it (which they calculated to be good for 498 kph at the nominal rating of 996 PS). Any other 109 in similar configuration with the same power should reach the same of course.

[Kurfürst]

Originally Posted by Glider

I do find this theory that the 109 will be able to turn better than a SPit at higher speeds a little foolish.

a) There are no, repeat no tests, from any side that support this theory.
b) The 109 locked up faster than a spitfire at higher speeds so the spit will have all the advantages getting into the turn by which time the 109 will be in the smelly stuff
c) You quickly lose speed in a turn which will nulify any theoretical advantages
d) The above description of what will happen shows the folly of this theory
e) The 12 boost throws the theory out anyway as it passes the power to weight ratio advantage to the SPitfire
f) Its worth remembering what the German test establishment said about the turning ability of these aircraft:-

Before turning fights with the Bf 109 E type, it must be noted in every case, that
all three foreign planes have significantly smaller turning circles and turning times.
An attack on the opponent as well as disengagement can only be accomplished on the basis of
existing superiority in performance.

Notice it doesn't say:-
a) The SPitfire is better at slow speeds
b) That the 109 can turn inside the Spitfire at high speeds
c) Ensure you keep your speed up against the Spitfire in a turning fight

It says basically DON'T GET INTO A TURNING FIGHT.

Can someone explain how the German test establishment got it so wrong.
After all they only had the real aircraft, real pilots to fly mock combats who obviously were very up to date on the Me109, amongst the finest engineers and designers in the world, people both well versed in the theory and experienced in this field, plus the resources of a test establishment.
I repeat the question, how did they get it so wrong?

Just explain how a plane with less or no excess thrust can pull a sustained turn better than a plane with more excess thrust, thank you.

How much excess thrust does a Spitfire at SL, running at +6 1/4 boost has at about 280 mph 1g at David?
How much more excess thrust does a Spitfire at SL, running at +6 1/4 boost require in 2g turn at about 280 mph David?
How much excess thrust does a Bf 109E at SL running at 1.35ata bppst has at about 280 mph 1g at David?

Which has a better sustained turn at 400 mph David, a Spitfire IX or a Me 262 (P-80 if you like)?

[JtD]

Originally Posted by Kurfürst

That's an unsustained turn. What you forget that in an unsustained turn, the 109 will still loose less speed than the Spit at high speeds, because the basics (=more excess thrust) did not change.

No, this isn't necessarily an unsustained turn. The same way the 109 has to give up level speed to turn, the Spitfire has, and for each change in turn rate, the speed loss of the 109 is higher, or for each loss of speed, the Spitfires turn rate change is larger. If the 109 settles at a load factor or turn rate, the Spitfire can do the same, at a lower speed.

It really sums up to that the 109's biggest advantage is in flying straight and level, it will remain competitive throughout the high & medium speed range, with the advantage always decreasing. All this, mind you, at sea level against a 6.25lb boosted Spitfire I, which is as good as it gets for the 109.

[MiG-3U]

Originally Posted by Kurfürst

Here.

Flight test.

That is a flight test ofa prototype doing 485kmh, non standard engine and 500kmh is a calculation based on non standard power.

Originally Posted by Kurfürst

Guranteed specs.

Not a test, more like a selling brochure.

But we have multiple tests results around 470kmh.

Originally Posted by Kurfürst

Yes. And?

That means two speed supercharger, no need for large oil cooler needed for the hydraulic clutch, less drag.

Originally Posted by Kurfürst

And have the DB 601Aa (not the DB 601A) in the sim, which had 1045 PS (1175 PS WEP) anyway. So the tested example had to reached 498 kph at 1018 PS. We have an 1045 PS variant. Are you saying that it should be even faster...

I can't find a 1C source stating that, please show me.

Besides 601A and Aa power settings are obviously different, 5min power fth is lower for Aa which means higher than 1.3ata.

Originally Posted by Kurfürst

I also have similiar curves for G-14, G-6, G-1 etc..

Nonsense curves and not relevant for this discussion, the rest is just your speculations.

[Kurfürst]

Originally Posted by MiG-3U

That is a flight test ofa prototype doing 485kmh, non standard engine and 500kmh is a calculation based on non standard power.

Wrong on all accounts.

Not a test, more like a selling brochure.

And with the specs laid down within being guaranteed within +/- 5% by the manufacturer of the product.

But we have multiple tests results around 470kmh.

Really. And what power, what supercharger settings, what airframe conditions?

That means two speed supercharger, no need for large oil cooler needed for the hydraulic clutch, less drag.

Speculation.

I can't find a 1C source stating that, please show me.

Look at the source files - or the fact that we a 5-min boost pressure of 1.35 ata...

Nonsense curves and not relevant for this discussion, the rest is just your speculations.

And one more scratch on the tail...

[Kurfürst]

Originally Posted by JtD

The same way the 109 has to give up level speed to turn, the Spitfire has, and for each change in turn rate, the speed loss of the 109 is higher

Because?

or for each loss of speed, the Spitfires turn rate change is larger.

Because?

If the 109 settles at a load factor or turn rate, the Spitfire can do the same, at a lower speed.

Yes.

It really sums up to that the 109's biggest advantage is in flying straight and level,

The 109s biggest advantage is its overall smaller drag, more powerful engine, and higher power to weight ratio, good harmony of controls (at least IRL) and superior near-stall handling IMHO.

it will remain competitive throughout the high & medium speed range, with the advantage always decreasing.

Agreed.

All this, mind you, at sea level against a 6.25lb boosted Spitfire I, which is as good as it gets for the 109.

Certainly. But then again, we haven't touched into the realm of 1.45ata WEP or a DB 601N under the hood. Or deploying flaps.