109's kill ratio (all variants from B to K)

[HoHun]

Hi Gripen,

>Well, there was boundary layer splitter in the early Bf 109F but on later models radiator design was simplified and splitter was removed.

Thanks, I wasn't aware of that! :-)

Regards,

Henning (HoHun)

[HoHun]

Hi Widewing,

>In point of fact, the P-51D was placarded at 300 mph IAS (539 mph) at 35,000 feet. That's Mach .81 and that ain't slow.

Well, my copy of AAF Manual 51-127-5 gives the redline speed at 35000 ft as 290 mph IAS and 500 mph TAS, which equals Mach 0.75, the value given in the manual as being just below the compressibility threshold. (Contradicting Curtis a second time.)

Of course, the P-51D could go beyond redline speed, but the Me 109 could go to Mach 0.79, too.

(290 mph IAS at 35000 ft convert into 520 mph TAS, but if you account for the compressibility error of the airspeed indicator you'll end up at a lower corrected value actually. Apparently, this wasn't usually taught to WW2 pilots, which gave rise to many exaggerated dive speed stories on both sides.)


Regards,

Henning (HoHun)

[HoHun]

Hi Widewing,

>Cutting to the chase, no Luftwaffe fighter used the Merideth Effect radiators even remotely as efficient as that designed by the North American team, period. End of discussion.

Do you actually have comparative efficiency figures? Then I'd like to ask you to share them with us so we might become enlightened, too :-)

If you don't ... well, "end of discussion" ;-)

Regards,

Henning (HoHun)

[Batz]

Ask him if he knows what mw50 is/does? That ought to be entertaining.

[F4UDOA]

Who cares??

Did you ever notice how many of these Luftwabble threads go in the same direction? If your super plane isn't the best then I must be a lunatic.

I'm out of this thread so you can wear your leather thong without fear of someone disagreeing with you.

Don't break your arms stroking to pictures of ole willie guy's.

[Neil Stirling1]

Mustang charts here,

Speed

http://hometown.aol.co.uk/JStirlingBomber/P51+-7+Merlin+speed.jpg

Climb

http://hometown.aol.co.uk/JStirlingBomber/P-51+-7+Merlin+climb.jpg

8th Airforce Mustangs 72"hg RAF Mustangs 81"hg with 100/150 grade fuel.

Thanks to Greg Shaw for the Graph paper.

Neil.

[JB42]

Ok this is erratating the watermelon out of me. It's a Bf109

[GScholz]

Originally posted by JB42
Ok this is erratating the watermelon out of me. It's a Bf109

As opposed to what?

[JB42]

They keep calling it a Me 109.

[GScholz]

Oh? Quoting wrongly from the Holy scripts of the Bayerische Flugzeugwerke? ... Those blasphemers!!!

[Charon]

Found this on the medideth effect from Air&Space magazine. It seems the Mustang fully utilized all the elemets required to maxamize the effect while planes like the Spitfire etc. only made it half way.

"It seems that most other contemporary airplanes attempting to take advantage of the Meredith Effect failed for one reason or another to combine an efficient duct system with a properly designed and regulated exit-closing mechanism and did not develop the energy recovery inherent in the Meredith method. They generally used 10 percent or more of their power available at high speed to overcome cooling drag. A notable exception was the DeHavilland Mosquito multi-purpose plane with the same Rolls-Royce engines and which used a wing leading edge radiator mounting with a short and direct inlet duct. The controllable exit opening had a minimum area little more than half that of the Spitfire, and while it was a larger two-engine airplane, it had a speed of 425 mph.

Here again, while Meredith's analysis was coherent and mathematically instructive, he failed to convey the practical aspects through an example or two, although he did offer a chart showing drag reduction for various discharge area ratios and conditions. The point I am making was that his work was generally in unfamiliar mathematical terms and was poorly understood. In fact, in two cases I know about, it was described in terms of mild ridicule. In any case, some if not most of the designs of wartime aircraft, including the Spitfire, failed to get the full advantage of this available air pump.

It should be pointed out here that the controversy and misunderstanding of the Meredith Effect on the performance of the Mustang developed largely because it was essentially impossible to get a reasonable measure of the effect from wind tunnel models at the time. The mass flow and momentum could not be accurately measured on a scale model, and no large tunnels were fast enough--200 to 400 miles per hour--to get meaningful results.

It has been reported that Messerschmitt made extensive efforts to determine the reason for the low drag of the Mustang, but his wind tunnel measurements did not disclose the restoration of momentum to the radiator cooling air, and most probably could not have done so with the wind tunnel equipment available at the time.

http://www.airspacemag.com/asm/mag/supp/jj99/Mustang.html

Charon

[niklas]

hmm i´m surprised that so many sources say the Merideth effect was devoverd in 35. This is not true, acutally Hugo Junkers had a patent already in 1915 for a ramjet cooler design.
The trick is always the same, slow down the air by increasing the flow area to minimize cooler drag. Nothing special.
Zero cooling drag would have made the P-51 way faster, just look at the 109R

niklas

[Charon]

If you Deutschland guys keep this "my national male unit is bigger than your national male unit" stuff going, the gloves are bound to come off: German noodlees 'too small for EU condoms'  

If it makes you feel any better, the designer of the P-51 was a German guy, so you can have your cake and eat it too.

Charon

[edit: LOL, just take this quote, and substitute Bf-109 for "german man"]

He denied the German man was any smaller than the rest of Europe, adding: "We think the EU has got its sums wrong, and if other countries were to check out their men's assets they would find the EU has made a mistake in its calculations.

[Batz]

Why bother even entering this thread if you are just going to be an arse?

It's f4udoa with noodle envy, just read his replies. It's folks like him and yourself that post inaccurate info and when corrected you decide to insult.

Niklas posted facts. They have nothing to do how you "feel".

The real question is why do you think it is necessary to throw insults when wrong? Trying to portray the p51 as some miracle plane is wrong.

[Widewing]

Originally posted by HoHun
Hi Widewing,

>Cutting to the chase, no Luftwaffe fighter used the Merideth Effect radiators even remotely as efficient as that designed by the North American team, period. End of discussion.

Do you actually have comparative efficiency figures? Then I'd like to ask you to share them with us so we might become enlightened, too :-)

If you don't ... well, "end of discussion" ;-)

Regards,

Henning (HoHun)

Hiya Henning,

In March of 1976 Lee Attwood spoke at a symposium where he produced data accumulated from both Britain and Langley comparing the total thrust loss to cooling drag after pressure recovery. The aircraft referred to were the Spitfire Mk.VIII, Bf 109G-6/R2 and a P-51D-10-NA. Losses were defined as a percentage of available thrust.

Spitfire Mk.VIII: 10.7%
Bf 109G-6/R2: 11.6%
P-51D-10-NA: 2.9%

The full text of Attwood's speech was published in the Spring 1977 issue of the American Aviation Historical Society Journal.

My regards,

Widewing