Author Topic: Draining E in turns (Read 10597 times)

Crumpp · « **Reply #330 on:** November 19, 2004, 04:44:55 PM »

Just got off the phone with Dr Timken to find out exactly what the deal on the time for the rack.

The rack and the doors are a little more involved than our previous conversations had led me to believe. A "couple of minutes" is more than 2 minutes.

Conservatively, working at normal not rushed pace:

For one man to remove the rack and mount the doors is an hour.

For a Luftwaffe ground crew it is about 15 minutes work.

The cockpit disassembly times I quoted are correct.

Crumpp

Angus · « **Reply #331 on:** November 19, 2004, 05:12:34 PM »

Very very nice.
I was thinking, when you said a couple of minutes, well, those could be a few

Nice to seeso much research being done.

Regards

Angus

gripen · « **Reply #332 on:** November 19, 2004, 06:15:33 PM »

The Fw-190A-5 is claimed to be "Gespachtelt u. poliert" so it certainly had a special finish (if that really is test data).

The ETC501 caused 12-15km/h speed loss (from the same pages).

gripen

Crumpp · « **Reply #333 on:** November 19, 2004, 07:21:20 PM »

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The Fw-190A-5 is claimed to be "Gespachtelt u. poliert" so it certainly had a special finish (if that really is test data).

Yes it is. It is marginally faster and marginally slower depending on the altitude then some of the other normal finished FW-190A5 graphs.

You can definately see now there is not a special finish on the FW-190A8.

The ETC 501 rack speed loss is also listed on the FW-190A8 graph I posted, Gripen.

Crumpp

gripen · « **Reply #334 on:** November 19, 2004, 11:16:18 PM »

Quote

Originally posted by Crumpp

You can definately see now there is not a special finish on the FW-190A8.

I can see that the speed difference between the US Navy Fw 190 (no wheel doors) and the Fw 190A-8 is neglible. The speed difference between Fw 190A-8 and the Fw 190A-5 can be mostly explained with the polishing because it gives about 15 km/h speed increase (according to Hoerner and Raunio).

gripen

Crumpp · « **Reply #335 on:** November 19, 2004, 11:23:07 PM »

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The speed difference between Fw 190A-8 and the Fw 190A-5 can be mostly explained with the polishing because it gives about 15 km/h speed increase (according to Hoerner and Raunio).

That would hold if it was not for the fact the other graphs show about the same difference between the FW-190A5 and the FW-190A8.

The FW-190A5 had the 12 bladed Lufterrad which made the FW-190 about 12 Kph faster. Polishing generally does not give such a dramatic increase as 15kph. 3-5 Kph is about right for the finish. Pyro has the other graphs.

Crumpp

gripen · « **Reply #336 on:** November 20, 2004, 03:10:28 AM »

Quote

Originally posted by Crumpp
That would hold if it was not for the fact the other graphs show about the same difference between the FW-190A5 and the FW-190A8.

The problem is that I don't see here any evidence of such graphs. If there really is such graphs, these might be with special finish as well. And are those supposed graphs flight tested? Only in the cases of the US Navy and RAE data I have seen evidence that these are flight tested.

The another problem here is that you have used a plane with special finish in a comparison. That is IMHO not fair.

gripen

Crumpp · « **Reply #337 on:** November 20, 2004, 06:26:16 AM »

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The problem is that I don't see here any evidence of such graphs. If there really is such graphs, these might be with special finish as well. And are those supposed graphs flight tested?

Your not going to either Gripen. Pyro has them though.

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That is IMHO not fair.

And comparing a Wooden Model to an actual aircraft of a different design is not??

Or data gathered from experimental Spitfire with various fuel pumps, props, intakes, etc...

Don't see you calling the unfair flag on that one.

Crumpp

KurfÃ¼rst · « **Reply #338 on:** November 20, 2004, 06:31:59 AM »

Quote

Originally posted by gripen

The another problem here is that you have used a plane with special finish in a comparison. That is IMHO not fair.

gripen

Hmm, I think Crummp already showed nicely that the plane has the standard finish, ie. primer etc. So why revert again to the "unfair special finish" thing? Besides, you were using Spit tests that were done with experimental planes with higher performance than the normal ones.. do you consider this 'fair'? Besides I don`t see what`s your problem with the A-5 data. The A-5 Handbuch states the same values, so obviously the data Crumpp uses isn`t anything extraodinary.

Why don`t you first agree which data is representative first, and then moving one step ahead?

Crumpp · « **Reply #339 on:** November 20, 2004, 06:54:02 AM »

As I stated before there is only a minor difference of 2-3kph comparing that graph to other FW-190A5 graphs.

It just did not have a great effect on the FW-190.

Crumpp

MiloMorai · « **Reply #340 on:** November 20, 2004, 07:51:02 AM »

gripen, the only way you can compare is 'like with like'.

A scale models data will get you in the 'ballpark' but can't be compared to full size data.

gripen · « **Reply #341 on:** November 20, 2004, 09:28:56 AM »

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Originally posted by Crumpp
Your not going to either Gripen.

No proof, no argument.

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Originally posted by Crumpp
And comparing a Wooden... blaah blaah

Not subject of this thread and no proof, no argument in that other thread too.

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Originally posted by Kurfürst
Hmm, I think Crummp already showed nicely that the plane has the standard finish, ie. primer etc.

I have been only referring sources which are available. Besides if you look back in this thread you will find me saying that the performance of the A-8 seems to be realistic and you will also find Crumpp stating (09-07-2004 11:03 AM): "They waxed it.". Generally it's very difficult to believe a person who continously changes his arguments and can't proof them.

Quote

Originally posted by Milo Morai
gripen, the only way you can compare is 'like with like'.

A scale models data will get you in the 'ballpark' but can't be compared to full size data.

Not subject of this thread but three short points:

1. We are not talking there about the total drag but change of the drag due to change of the Cl.
2. I'm not making drag comparisons nor other comparisons between planes there except comparisons to generalized formulas and lift distribution.
3. The Fw data is very probably determined with the models as well.

If you want to discuss more about this, please post to that thread.

gripen

Crumpp · « **Reply #342 on:** November 20, 2004, 10:08:48 AM »

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Besides if you look back in this thread you will find me saying that the performance of the A-8 seems to be realistic and you will also find Crumpp stating (09-07-2004 11:03 AM): "They waxed it.". Generally it's very difficult to believe a person who continously changes his arguments and can't proof them.

LOL,

Squirms of the dying argument....

Gripen that is new one on me. Only thing I recall is your claim that the USN data was correct and the graphs I put up were unrealistic because of the "filled and polished".

Now your claiming your felt the FW-190A8 data was correct the whole time!!

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No proof, no argument.

There is proof. You just don't have it and are not going to get it from me.

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gripen, the only way you can compare is 'like with like'.
A scale models data will get you in the 'ballpark' but can't be compared to full size data.

Absolutely Correct. You should listen Gripen.

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The Fw data is very probably determined with the models as well.

Not hardly. It's off of real aircraft. In December of 1944 the Germans were possesion of several windtunnels large enough to conduct these experiments. Any aeronautical engineer will tell you that trying to get exact drag data off a wooden model will not compare exactly with the full scale flying version of the aircraft. You can only draw general conclusions NOT specific numbers.

Crumpp