Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained) (2 Viewers)

[buffnut453]

I believe the Soviets made almost exactly these changes and defeated the Luftwaffe with it.

Of course they did...and the Yaks, LaGGs, MiGs, Lavochkins etc had nothing to do with it, right? You're also ignoring (yet again!) that the air war on the Eastern Front was fought at a much lower altitude than was the case on the Western Front.

You really need to start acknowledging what you don't know and what you don't believe if we're ever to make ANY progress in this discussion.

 

[GregP]

Hi P-39 Expert. You have shown pretty good patience with the forum considering some of the posts that have been thrown at you. I have seen none of the typical internet personal attacks coming from you to us.

But, you also do not appear to be paying attention to any of the knowledge being shown to you. The moderators are being pretty patient, but I doubt things will continue to be as patient if you do not at least acknowledge some of the plain old in-your-face shortcomings of the P-39 family. It was not one of our better fighters, but it could and did thrive in a very short-range, low-altitude combat environment in Russia. Other than that narrow niche, it was not of much use to anyone and, while some South Pacific commanders welcomed it, they did so because nothing else much was available to them until Germany was beaten since Europe was the number one priority. They had to settle for what they could get. In some cases, that meant the P-39. Nobody much was happy about it, but some fighters were better than no fighters, even if they couldn't go very far or do very much due to the overwater ranges involved.

You need to let the P-39 go and just be a regular posting member of the forum. Everyone is very tired of P-39s, not just me.

Sorry if this steps on anyone else's toes.

Cheers, and I hope to be seeing you in threads OTHER than P-39 threads.

 

[P-39 Expert]

It depends on how you want to compute the range.

The USAAF, rightly or wrongly, in their comparisons charts did not credit any horizontal movement in the climb to 25,000 ft cruising altitude. This was to allow for forming up and rendezvousing with the bombers. If you want to come up a figure for range/radius to compare to the planes listed in the chart then you have to use the conditions the chart says. We are talking about the chart in the pilots manual, right? Or a different chart?

You have yet to explain how a plane that reaches 5000ft gets to 20,000-25,000 without using addition fuel over and above the fuel needed to cruise at 5,000. The Flight Operation Instruction Chart (range chart) computes range by deducting the warm up, takeoff and climb allowance from total fuel, then dividing that net fuel by GPH (giving hours of operation) and multiplying that by TAS. That computed range number is always less than the range on the chart indicating an allowance has been made for climbing from 5000ft to the desired altitude and the miles gained during that climb toward the target.

Please show in the manual or on the charts where it says " ranges in the range chart have already been adjusted down to reflect both the fuel used in climbing from 5000ft and the miles of range gained during the climb" It sure doesn't say that on the P-39Q charts. Show me where the manual says "go to the Takeoff, Climb and Landing chart and use fuel from S.L. as the takeoff allowance."


If you wish to use your method of range commutation then please compute the ranges for the planes you are comparing to the same way. The range chart is computed the same way for every AAF fighter that has a pilot's manual.

BTW, everybody should read the fine print at the bottom of the Climb charts for all aircraft.

For some reason the US did not use standard temperature and pressure for these charts. They used 0 degrees C (32 degrees F) instead of 15 degrees C/59 degrees F.
Some charts, like the P-39Q chart leave the correction blank, other charts say 10% increase in climb time for EVERY 10 degrees C above 0. True, but wouldn't your opponent be flying in the same air and weather? Wouldn't they also have the same limitations?

Expand above.

 

[P-39 Expert]

"Wings had the SPACE to mount fuel tanks where the wing guns were mounted. "

You would have space in two dimensions. Now the question is it was smart.

Fuel tanks fitted between the forward spar and the Main spar, the distance narrows between the spars the further out you go.
The wing gets thinner there further out you go. The wing at the W-2 position indicated on the drawing is less than 8 inches thick at max, it is a bit thicker where the machine guns are.

Self sealing fuel tank material is pretty much constant thickness and weight per sq ft. A long, skinny, thin tank is going to use a lot more self sealing material than a short fat tank of the same capacity. a tank with an assumed thickness of 6.5 inches (allowing for Self sealing material as a guess, corrections welcome) you need almost 2 sq feet of tank to hold ONE gallon.
Granted that is worst case, but it shows that fuel tanks in the last few feet of a wing are poor proposition. Lots of tank weight for not that big an increase in fuel. A tank at mid point in the wing may hold 50 % more fuel per sq ft of wing area than tank in the outer wing for the same weight of self sealing material due to being thicker.
when outer wing tanks are full role response is poor. The post-war P-39 racing planes held 100gal in the outer wings (50gal per side). I'm saying that 30 additional gallons would be plenty (150gal total) which would be only 15gal per side. The entire area where the tanks would go in the outer wing is clear area, not broken up by wing ribs as in the normal P-39 wing tanks. Roll would be no worse than with wing guns and full ammo boxes, weight would be about the same.


"N was not a low altitude plane."

Engine peaked at 15,000ft or so. Yes there were lower altitude planes but many fighters had engines that peaked in the 20,000ft foot range.
Spitfire II engine peaked 17,500ft in the summer of 1940. I suggest you should not worry so much about the specific performance of each engine, but more about the performance of the plane that the engine was installed in. P-39 had less drag than Spitfire.

Expand above.

 

[pbehn]

And you misspelled specializing.

In which language? Bearing in mind the language is English.

 

[DerAdlerIstGelandet]

Cheers, and I hope to be seeing you in threads OTHER than P-39 threads.

And then those will become P-39 circle jerk threads...

 

[GrauGeist]

In which language? Bearing in mind the language is English.

I suppose you'll have to translate everything to American English, in order for the conversation to flow without stopping for assumed grammar correction.

 

[pbehn]

I suppose you'll have to translate everything to American English, in order for the conversation to flow without stopping for assumed grammar correction.

I had the same problem in Saudi Arabia, a computer nerd from Texas told me he couldnt understand my English, as if that is my problem not his, there were people from all over the world there and he didnt understand any of them, and that was their fault too. Many of the guys he was complaining about had English as a second or third language and some I knew could speak six.

 

[P-39 Expert]

Hi P-39 Expert. You have shown pretty good patience with the forum considering some of the posts that have been thrown at you. I have seen none of the typical internet personal attacks coming from you to us. Thank you very much, I have always tried my best to be non-snarky.

But, you also do not appear to be paying attention to any of the knowledge being shown to you. The moderators are being pretty patient, but I doubt things will continue to be as patient if you do not at least acknowledge some of the plain old in-your-face shortcomings of the P-39 family. It was not one of our better fighters, But it and the P-40 were all that was available in 1942. but it could and did thrive in a very short-range, low-altitude combat environment in Russia. Only difference between combat on the eastern front and the western front was high altitude bombing by B-17/B-24 and that didn't really get going seriously until mid-'43. The 1943 P-39s were not low altitude planes and were capable of matching performance of the FW190A and Me109G up to 8000 meters and the Luftwaffe didn't care to go any higher than that. Other than that narrow niche, it was not of much use to anyone and, while some South Pacific commanders welcomed it, they did so because nothing else much was available to them until Germany was beaten since Europe was the number one priority. They had to settle for what they could get. In some cases, that meant the P-39. Nobody much was happy about it, but some fighters were better than no fighters, even if they couldn't go very far or do very much due to the overwater ranges involved. Again it was all that was available in 1942, along with the P-40 and F4F. 1942 was primarily a defensive war in 1942 for the AAF in the Pacific. Range was not as important then as the ability to fight at Zero/Betty altitudes. Lighter P-39s would do that.

You need to let the P-39 go and just be a regular posting member of the forum. Everyone is very tired of P-39s, not just me. Part of the reason these threads go on so long is for every one of my posts there are usually 5-10 posts back from you guys poking fun at me. No problem, I like fun (as should be evidenced by my handle) but if we could stick with the subject matter the threads wouldn't be nearly so long. All I'm trying to do is show you that most of the old crap about the P-39 is wrong, or at least confined the the heavy 1942 P-39s. Lots of information has been made available in the last 10 years (wwiiaircraftperformance.org, Soviet records, books etc.) that maybe (obviously) you had not seen. Never said the P-39 was a world beater, just that it was a good bit better than we all had been led to believe.

Sorry if this steps on anyone else's toes.

Cheers, and I hope to be seeing you in threads OTHER than P-39 threads.

 

[DerAdlerIstGelandet]

I had the same problem in Saudi Arabia, a computer nerd from Texas told me he couldnt understand my English, as if that is my problem not his, there were people from all over the world there and he didnt understand any of them, and that was their fault too. Many of the guys he was complaining about had English as a second or third language and some I knew could speak six.

Dagumit, haven't you lurnt American?!

Speke Merican or die!

 

[GrauGeist]

I never have trouble with folks who speak "British" English or Europeans who have been schooled in proper English.
I am fluent in American English, Californian english and was tutored by a retired Oxford English professor when I was a child, because of my severe dyslexia.

So that may be why it's a non-issue for me. I would also never interrupt a conversation to point out (real or imagined grammar mistakes) - it's rude as hell.

 

[Shortround6]

There are range charts in the Back of AHT, Pages 599 and 600.
They are the ones with bar graphs.

 

[pbehn]

Dagumit, haven't you lurnt American?!

Of course, there are very few Americans I dont understand. Same in UK if I speak in my local "argot" its hard for others to understand so I dont, My parents came from darkest Yorkshire, 45 miles away and my wife didnt understand a word when they all got together with friends. The problem with this guy Dave from Texas is he was 24 and had never been outside Texas. He really didnt believe that there were people who didnt speak English, funny to watch, like a comedy sketch and it happened every time we went into a shop.

 

[pbehn]

I never have trouble with folks who speak "British" English or Europeans who have been schooled in proper English.
I am fluent in American English, Californian english and was tutored by a retired Oxford English professor when I was a child, because of my severe dyslexia.

So that may be why it's a non-issue for me. I would also never interrupt a conversation to point out (real or imagined grammar mistakes) - it's rude as hell.

As an Englishman abroad you become everyones English teacher. Most of the time I wouldnt correct anyone on anything, its rude and interrups the flow of a conversation, unless they were making an error that meant they were not saying what they thought they were or were saying something offensive without knowing (it happens). Four translators I met abroad were self taught, so it want just their job but their interest and hobby. It is interesting and at times hard work figuring out how and why we say what we do, especially to Chinese and Japanese whose languages work in a completely different way.

 

[FLYBOYJ]

OK - enough!

It's bad enough this thread keeps going around in circles but P-39 EXPERT, you WILL start using the proper reply format to respond from here on end. Several members openly complained and it is getting cumbersome.

I'm willing to let the horse beating continue but please follow the forum requirement when replying!

 

[FLYBOYJ]

On Page 83, it's clearly spelled out how to do this - please follow this direction.

Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained)

 

[Marcel]

I thought some of you had been here long enough to know that in order to stop talking to a brick wall, you just have to stop talking. But maybe I overestimated that?

 

[glennasher]

I thought some of you had been here long enough to know that in order to stop talking to a brick wall, you just have to stop talking. But maybe I overestimated that?

I believe I brought that up, maybe in those exact words, almost a year ago, now. I'm as guilty as anyone conversing with masonry, though, and I freely admit it. d:^)

 

[pbehn]

Dagumit, haven't you lurnt American?!

Speke Merican or die!

I think you may like this a German professor explaining Geordie which is from 50 miles north of myself and Rochie



and this from Yorkshire 50 miles south

.

My grandmother used to read books in Yorkshire dialect which is English words with different meanings and German grammar. She would often say "I doubt" at the end of a sentence, which actually meant "I think" or "Ich denke".

 

[Thumpalumpacus]

I would also never interrupt a conversation to point out (real or imagined grammar mistakes) - it's rude as hell.

I'm a writer by hobby and a lover of the language by nature. So long as I can understand what is being said or written, I don't complain about grammar or spelling, because I reckon that communication is more important than perfection.

I see such trivial corrections as a matter of someone trying to avoid a point by focusing on language instead of message.

It's not only rude, as you say -- especially on a forum where the native language of many posters is not English -- it's also dissimulative, in the sense that if one makes a typo, misspelling, or grammatical error, that is alleged to impugn the point being laid.

It's lazy, cheap, and the refuge of someone who cannot answer the point.

If you know what someone means, then focusing on the correctness of how they write is dishonest.