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BillSwagger
08-04-2009, 02:17 AM
which was a tougher more durable plane??

The P-47D-22 or the FW190-A5:


The P-47D-30 or the Fw190-D9:



Id contribute my opinion, but it would be difficult for me to be impartial.

DKoor
08-04-2009, 02:58 AM
Hard to say anything smart without writing an essay...

Depends on this, that etc.

I'll try to make it short.

If they are all being exposed to .50cal fire I'd say P-47.

But since they are not, I suppose they are even, or perhaps FW is even more durable.

Gammelpreusse
08-04-2009, 03:32 AM
The P-47 is a legend when it comes to toughness. The size and displacement of that plane, combined with it's rugged construction and the big bad radial engine makes that obvious at first glance already.

The FW190 is smaller, much tighter packed and thus, when hit, more prone to catastropic damage. That aside, however, it was by all accounts a very tough plane as well and had a reputation as such.

There once was a report of a 47 pilot over Paris, emptying all his ammunition into a 190, the only result beeing a small trail of smoke.

Will have to check the web, maybe I'll find that story again.

That said, the P47 strikes me as the undoubtly tougher plane.

K_Freddie
08-04-2009, 04:54 AM
There's also reports from frustrated FW pilots, 'emptying' all their magazines on P47s, only to see them fly away.
I vaguely remember a report about such an encounter and when the p47 was back at base they counted about 100 holes of varying sizes in the plane.

When I come across a p47... I always try get the pilot.
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

SILVERFISH1992
08-04-2009, 07:59 AM
If your going to be hit by a 50 meter ball of fire and shrap melt at 200 mph wHILE sitting in a hanger, then I would recomend the FW-190. http://forums.ubi.com/images/smilies/59.gif

J_Weaver
08-04-2009, 08:13 AM
P-47, IMO.

Both were tough birds, but the Jug was a beast. I remember seeing pics of a P-47 that his a telephone pole on a strafing run. It broke the danged pole off and kept on truckin'. http://forums.ubi.com/groupee_common/emoticons/icon_eek.gif

JtD
08-04-2009, 08:46 AM
The P-47 was no doubt structurally tougher, but it also was considerably larger and thus easier to hit. The turbo added another area of vulnerability the Fw did not have. Same goes for fuel wing tanks.

Overall, I think the Fw was the better compromise for the fact that it managed to pack a lot of strength into a very small airframe. Better to be missed with no effect than hit with little effect.

BRASSTURTLE
08-04-2009, 11:29 AM
JUG.
JUG again.
Granted I am very biased, but the evidence is out there.

One brought a piece of guy wire for the ride back to England, wrapped around the prop.
Another hit a brick chimney & brought back souvenirs.
One landed with a 500 pounder stuck on the center line that came loose on landing & detonated. The pilot lived.
Name ONE other fighter that could do that.
K_FREDDIE,the story I think you are referencing was Robert S Johnson vs. Egon Mayer.
21 cannon strikes & about 200 bullet holes.
See Mystic Puma's "Not my time to die" for an excellent depiction of this story.
here: http://forums.ubi.com/eve/foru...1068925&r=5241068925 (http://forums.ubi.com/eve/forums?a=tpc&s=400102&f=23110283&m=5241068925&r=5241068925)

Not that the 190 is a weak bird. Far from it.
But the Jug was a flying tank (and flew like one)
The A5 I would think would be tougher than the Dora, just based on Air vs Water cooled.
One bullet or large bug & the Dora becomes an armed glider. The R2800 was shown again & again to come home with whole cylinders missing.


JUG FTW!!!

MD_Titus
08-04-2009, 11:51 AM
bigger guns so it has to be the 190. preferably an a8 or a9 with the mk108's, but even the mg-ff's can be useful. get a p-47 in a mixed hail of 30mm and 20mm and it's good night. with a p47 you need to track the bandit a fair bit more to cause that catastrophic damage. however the 190 is more vulnerable to wing damage from the .50'swhich knock a fair bit off in terms of stability and speed, also pk's and controls from the bank of 8 .50's can make it dicey. co alt and head on it comes down to gunnery. in an uneven fight then whoever has the alt or speed to get that alt.

i'd rather be in the 190 than the p47 though.

Xiolablu3
08-04-2009, 12:11 PM
If you mean tougher as in which could absolrb most punishmet, then I would say P47.

But the Fw190 was still a very tough bird with regards to its size compared to the high performance in-lines like the Spitfire, Bf109 and P51.

BillSwagger
08-04-2009, 12:55 PM
Being hit in any plane would suck, but which could withstand more abuse??


Originally posted by JtD:
The turbo added another area of vulnerability.

This was also the component that help cushion a rough landing, as well as provided more hardware to block shrapnel from flack or gunfire.



Same goes for fuel wing tanks.


Unless you're referring to drop tanks, the P-47D didn't have wing tanks, and i'm not sure if the 190 did either.


My opinion is simple.
Larger planes absorb more punishment. This was especially true of the P-47. They were very consistent at getting to their targets and getting their pilots back home. Some were also shot down, however most made it home and were almost always riddled with flack holes, to the point where any other plane would fail to fly, including the 190. (there are some variants of the 190 that are better suited for ground/bomber fire, but I'm not referring to those here)

The 190 is a smaller plane and somewhat more durable than planes of similar size because of its radial engine. Perhaps that's where this reputation for ruggedness comes from, however when put side by side with the P-47, the 47 was a much tougher plane.
I could probably set aside two or three stories of amazing triumph for every fighter plane that served in WW2, but I think the toughness of the 190 only went so far, and could not out last the flack the P-47 often flew through and survived.


I recently read that a majority of Gabby's kills were made in a P-47D-11, a rather primitive variant, to my surprise.

JtD
08-04-2009, 01:29 PM
Yes, you're right. I was into N already.

If the turbo blocks shrapnel or AAA, it might set the whole plane on fire, same goes for rough landings.

BillSwagger
08-04-2009, 02:12 PM
There is an oil cooler back there too, which I'm sure could be fuel source for fire, but its a relatively small target in proportion to the turbo system. I'm not sure how the turbo could set a fire considering its pretty much a high tech fan and some ducting. The inter cooler has some fluids in it similar to antifreeze but they wouldn't be any more flammable than coolant in certain engines.
Fires back there were rare, by comparison, from what i've read, but you are right when saying the turbo is another component to take damaged.
Still better the component than an immediate pilot kill or shattering of armor that protects the pilot.
The turbo charger is still largely just ducting and extra space other than the turbine and fans, however.

http://www.aviation-history.com/republic/p47-turbo-sys-3.jpg

horseback
08-04-2009, 03:09 PM
I suspect that the record will show that the Thunderbolt was considerably more durable than the FW 190 in any of its varieties. There are far too many documented examples of Jugs coming home with tree limbs in the wings, engine cylinders knocked or shot off, 100+ bullet holes, shredded rudders and elevators, and telephone poles, power cables or chunks of enemy aircraft lodged in the wings or cowling. Add in the pilot memoirs and it has to be the most memorable quality about an aircraft that excelled both as a high altitude fighter and as a close support mudmover.

American combat aircraft of that era had a well deserved reputation for being over engineered, that is, built to withstand greater stresses than their European and Japanese counterparts, and the P-47 was the most extreme example of that reputation. It was the safest American combat aircraft of the war in the sense that if you took it into combat, you were far more likely to get back to base afterwards.

A more reasonable question might be ‘how much more durable was the Mustang than the Focke-Wulf?’

cheers

horseback

VW-IceFire
08-04-2009, 03:20 PM
In my mind the P-47 Thunderbolt is tougher. Its an extremely rugged design in virtually every place. There isn't much on the Thunderbolt that could be considered a weak link...yes its ultimately vulnerable from enemy fire but its a toughie.

The Fw190 is also a very well built plane with solid construction but its the size of the Thunderbolt and its turobsupercharger gear that gives it the edge. By no means should the Fw190 be considered a vulnerable plane...its not. The P-47 has one or two natural advantages.

BRASSTURTLE
08-04-2009, 03:22 PM
I recently read that a majority of Gabby's kills were made in a P-47D-11, a rather primitive variant, to my surprise.

It was my understanding that Gabby preferred the razorback due to the greater lateral stability.
Warbird Resource Group has one listing wrong for the planes he flew. HV A ser# 42-25864 is listed as a P47D-22- <span class="ev_code_RED">RE</span>
This would be incorrect. The dash 22 was an RA.
Small point, but one that bugs me. Farmingdale taking all the credit. Like Spits & Hurri's.

To put the final nail in the coffin of the FW190, how many ORIGINAL BUILD Wurgers are still flying?
How many Jugs? (listens to the crickets)

VMF-214_HaVoK
08-04-2009, 03:27 PM
The P-47 was IMO. The Antons were notably tuff aircraft and featured a radial engine. I would not put my money on the Dora. All great aircraft nonetheless. There is no real answer though...only opinions.

VW-IceFire
08-04-2009, 03:58 PM
Originally posted by BRASSTURTLE:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">
I recently read that a majority of Gabby's kills were made in a P-47D-11, a rather primitive variant, to my surprise.
To put the final nail in the coffin of the FW190, how many ORIGINAL BUILD Wurgers are still flying?
How many Jugs? (listens to the crickets) </div></BLOCKQUOTE>
Thats not really a relevant consideration. Politics and historical circumstance weighs much more heavily here. For the Thunderbolt they were kept on in air national guard units until the early 1950s or late 40s (I can't remember which). After that they were sold privately, used in air races, and so forth. For the FW190 they were scrapped, plowed under, and otherwise destroyed so as to prevent their use. A precious few still exist were transfered to Britain and the US and those are still around. One of them even has an engine that starts.

But really what we're talking about is a tale of two nations. One nation that came out of the war stronger and more influential than before with a fully scaled up industry, professional military, and worldwide capabilities. The other nation was broken up into two parts, suffered years of uncertainty and was more focused on rebuilding than maintaining a history that wasn't well liked.

Viper2005_
08-04-2009, 04:46 PM
Originally posted by BillSwagger:
I'm not sure how the turbo could set a fire considering its pretty much a high tech fan and some ducting.
http://www.aviation-history.com/republic/p47-turbo-sys-3.jpg

1) It's hot; the turbine is very hot.
2) It has an oil system.
3) It has an awful lot of kinetic energy.

So if the turbo itself fails then a large amount of damage is likely to result.

If the ducting taking engine exhaust to the turbo fails then fire is likely:

http://www.wwiiaircraftperform...-47/p-47d-74616.html (http://www.wwiiaircraftperformance.org/p-47/p-47d-74616.html)

Freiwillige
08-04-2009, 05:23 PM
Without any scientific tests this can only be opinion (Mostly uneducated myself included) and speculation.

There is no doubt that the P-47 was built like a brick Out House and many stories make the P-47 legendary.

But alas the FW has many German stories of durability as well.

One thing is for absolute certain though, Both aircraft could and would be shot down on a regular basis throughout the war.

Even the Sturmovik, Concrete bomber was lost in tremendous numbers.

1 bullet can take any aircraft down as long as that 1 bullet hits the weakest link (Usually between the pilots eyes)

BillSwagger
08-04-2009, 10:51 PM
Originally posted by Viper2005_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BillSwagger:
I'm not sure how the turbo could set a fire considering its pretty much a high tech fan and some ducting.

1) It's hot; the turbine is very hot.
2) It has an oil system.
3) It has an awful lot of kinetic energy.

So if the turbo itself fails then a large amount of damage is likely to result.

If the ducting taking engine exhaust to the turbo fails then fire is likely:

http://www.wwiiaircraftperform...-47/p-47d-74616.html (http://www.wwiiaircraftperformance.org/p-47/p-47d-74616.html) </div></BLOCKQUOTE>

Holes in the ducting do not cause fire.
There are a few other factors.
"Any simultaneous occurrance of smoke with high thermocouple temperatures and zero tachometer readings with subsequent drop in manifold pressure should immediately warn the pilot to close the turbo and to leave it in the "off" position. "

Fire (loose term here) is likely if the pilot doesn't take measures to lower the turbo and reduce temperatures.
The problem in that test was a broken coupling. The damage was done when the pilot wasn't able to make proper adjustments because of an improper turbo temperature reading.

I'm still trying to figure out how exhaust ignites from hot metal alone. Even if the metal were red hot hypothetically, how does it ignite exhaust fumes?

Hot metal doesn't ignite gasoline. i guess the hot exhaust could heat up another part to the point of where it would begin to melt or burn, but there would be no open flame, just more smoke, but the damage to such parts from over heating would be very critical.

ImpStarDuece
08-04-2009, 11:24 PM
Originally posted by BRASSTURTLE:
To put the final nail in the coffin of the FW190, how many ORIGINAL BUILD Wurgers are still flying?
How many Jugs? (listens to the crickets)

How disingenuous.

Using this argument, you could then conclude that the P-51 or Spitfire (perhaps the P-40 as well), were more rugged than the P-47.

Afterall, more of them survived the war and are still flying...


A more interesting approach might be a detailed correlated statistical analysis, peppered with pilot accounts and combat reports. Take a look at USAAF records and work out the % of P-47s that survived damage and then compare it to other USAAF S/E fighters.

The records are fairly comprehensive. There were just under 570,000 USAAF fighter sorties against Germany/Italy between 1943 and 1945 and another 39,000 in theatres against Japan, resulting in 11,000 fighter losses. So, it shouldn’t take more than a few months http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

Then take the RAF’s records and look at their S/E fighter survival rates. Might be more problematic, as the RAF records are not quite as complete as the USAAF’s.

Then go and do it for the Luftwaffe. More problematic again.

The General Quartermasters returns might be the best place to start. The difficulty that emerges is the very scanty nature of Luftwaffe records, particularly for the later war period. Apparently only about 12% of their records survived the war intact, although the Russian archives reportedly have tens of thousands of documents still waiting to be classified, seized after the taking of Berlin.

Then continue to write and research for a couple years, sign a book deal and publish the lot. Then watch people on flight sim forums pick apart your method and research with all the elegance of apes flinging feces http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

Simple.

BillSwagger
08-04-2009, 11:32 PM
Originally posted by Freiwillige:
Without any scientific tests this can only be opinion (Mostly uneducated myself included) and speculation.


well pick one...dang it.. http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

I don't consider myself an expert, but you'd be surprised what you can learn with a dollar, twenty five and a library card.
I wouldn't be so quick to discredit others opinions, including your own.

WOLFMondo
08-04-2009, 11:45 PM
Originally posted by BillSwagger:


The 190 is a smaller plane and somewhat more durable than planes of similar size because of its radial engine. Perhaps that's where this reputation for ruggedness comes from, however when put side by side with the P-47, the 47 was a much tougher plane.

The 190's toughness came from its amount of armour compared to other fighters of its day (how many other single engine fighters came with armour around the engine as standard other than a single firewall?) and British tests confirmed that a .50 from a dead 6 into the 190 wouldn't do very much. I belive it also had control rods rather than cables.

It probably gave the appearance of toughness over the 109 as well given the 190 was easier to fly with its electric systems and better cockpit.


Originally posted by BillSwagger:
I'm not sure how the turbo could set a fire considering its pretty much a high tech fan and some ducting.

Turbo failures can be massivly catestrophic, if one of those blades comes off it will leave the plane at a very fast speed.

JtD
08-05-2009, 12:13 AM
Exhaust fumes often contain unburned components of the fuel. If the mixture is rich, like it usually is in combat, there's a lot left.

It has also been pointed out that fire isn't the only danger a turbo has.

It's not that a hit to a turbo means instantaneous critical damage to the plane, but it certainly is a bad spot to hit.

-----

I'd usually use "over engineered" to describe items that contain a lot of unessential technical gadgets and functions, not items that are very tough. For that reason I'd label the Fw 190 over engineered, not the P-47.

deepo_HP
08-05-2009, 12:34 AM
Originally posted by BillSwagger:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Freiwillige:
Without any scientific tests this can only be opinion (Mostly uneducated myself included) and speculation.


well pick one...dang it.. http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

I don't consider myself an expert, but you'd be surprised what you can learn with a dollar, twenty five and a library card.
I wouldn't be so quick to discredit others opinions, including your own. </div></BLOCKQUOTE>
so why did you open the thread with the question:
'which was a tougher more durable plane??'

it doesn't look like an evaluation of opinions, but a request for facts or specific arguments. but it also seems, that you have made your mind up already, so what exactly is this meant to be?

i'd say, that i tend to agree with freiwillige... stories of devastated homecoming p-47s don't compare to scientifical tests.
and viper's thoughts on vulnerable points are pretty close to what i expected to read under this topic.

na85
08-05-2009, 12:57 AM
Originally posted by BillSwagger:

Hot metal doesn't ignite gasoline. i guess the hot exhaust could heat up another part to the point of where it would begin to melt or burn, but there would be no open flame, just more smoke, but the damage to such parts from over heating would be very critical.

Hot anything can ignite gasoline fumes. Gasoline, like any other fuel, has a spontaneous combustion temperature, and if that temperature is exceeded, then fire starts.

Additionally, if the Turbo flies apart and pieces of it are crashing through the inner guts of the aircraft, there are fuel and oil lines back there and if one is cut and exposed to a spark from a piece of turbocharger flying through it, then again: fire.

ImpStarDuece
08-05-2009, 01:12 AM
Originally posted by JtD:

I'd usually use "over engineered" to describe items that contain a lot of unessential technical gadgets and functions, not items that are very tough. For that reason I'd label the Fw 190 over engineered, not the P-47.

Quite curious. What "unessential technical gadgets and functions" did the FW-190 have?

Bremspropeller
08-05-2009, 02:22 AM
None.

BillSwagger
08-05-2009, 02:39 AM
Originally posted by na85:
Hot anything can ignite gasoline fumes. Gasoline, like any other fuel, has a spontaneous combustion temperature, and if that temperature is exceeded, then fire starts.



yes, but heated metal isn't hot enough.
You can try it. (you didnt here it from me), but take a cup of high octane gas 107 rated, and heat up a chunk of metal, like a large wrench until its red hot. Then dunk it in the gasoline.
No fire...lots of potent vapor, but no fire.
http://i145.photobucket.com/albums/r201/spre77/books_002.jpg

Exhaust vapor is already really hot, and even with a rich mixture, it being a high octane gas will burn a majority of the gas by the time it gets to the inter cooler. Part of the problem with a damaged duct, is the hot fumes are now pouring into other parts of the plane exposing them to higher temperatures than what they are designed for. (this is whats described in the test) Some parts even smolder and smoke as they burn, but there is no actual open flame. The oil cooler is the only part i see as a true fire hazard, and even that would need an ignition source.

BillSwagger
08-05-2009, 02:48 AM
Originally posted by deepo_HP:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BillSwagger:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Freiwillige:
Without any scientific tests this can only be opinion (Mostly uneducated myself included) and speculation.


well pick one...dang it.. http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

I don't consider myself an expert, but you'd be surprised what you can learn with a dollar, twenty five and a library card.
I wouldn't be so quick to discredit others opinions, including your own. </div></BLOCKQUOTE>
so why did you open the thread with the question:
'which was a tougher more durable plane??'

it doesn't look like an evaluation of opinions, but a request for facts or specific arguments. but it also seems, that you have made your mind up already, so what exactly is this meant to be?

</div></BLOCKQUOTE>

Deepo, i was just making the point that you dont need to be an expert to have an educated opinion.

My mind is made up, only because the bulk of knowledge that I have on both planes and the war tells me so. You can disagree, if you want, in fact i started the thread to here what other peoples opinions were.
Try not to over think it.

deepo_HP
08-05-2009, 03:35 AM
the reason why i replied is, that i don't understand why you make up a thread on a rhetorical question.

if you made up your mind already, then ask: 'i think, the p-47 is more durable than a fw-190, anyone thinks different?'
you didn't make any point here, and your reply to freiwillige was out of context.

i don't agree or disagree with any well made statement, but i disagree with subtle questions, which seemingly intend just to prove a made up opininion, which is yours.

if you disagree with that, you should consider asking better questions in threads which you start. i may be not too eloquent with this language, but i pretty much understand well the topic as stated in the thread's title.

so, again... why did you start this?

BRASSTURTLE
08-05-2009, 07:57 AM
Originally posted by ImpStarDuece:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BRASSTURTLE:
To put the final nail in the coffin of the FW190, how many ORIGINAL BUILD Wurgers are still flying?
How many Jugs? (listens to the crickets)

How disingenuous.

Using this argument, you could then conclude that the P-51 or Spitfire (perhaps the P-40 as well), were more rugged than the P-47.

Afterall, more of them survived the war and are still flying...


A more interesting approach might be a detailed correlated statistical analysis, peppered with pilot accounts and combat reports. Take a look at USAAF records and work out the % of P-47s that survived damage and then compare it to other USAAF S/E fighters.

The records are fairly comprehensive. There were just under 570,000 USAAF fighter sorties against Germany/Italy between 1943 and 1945 and another 39,000 in theatres against Japan, resulting in 11,000 fighter losses. So, it shouldn’t take more than a few months http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

Then take the RAF’s records and look at their S/E fighter survival rates. Might be more problematic, as the RAF records are not quite as complete as the USAAF’s.

Then go and do it for the Luftwaffe. More problematic again.

The General Quartermasters returns might be the best place to start. The difficulty that emerges is the very scanty nature of Luftwaffe records, particularly for the later war period. Apparently only about 12% of their records survived the war intact, although the Russian archives reportedly have tens of thousands of documents still waiting to be classified, seized after the taking of Berlin.

Then continue to write and research for a couple years, sign a book deal and publish the lot. Then watch people on flight sim forums pick apart your method and research with all the elegance of apes flinging feces http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

Simple. </div></BLOCKQUOTE>
My first successful troll!!
I thought i had hooked 2, but after re-reading your post, I realize I only hooked IceFire.
Only took me 5 years.
Ice, I had considered the P-51 argument.
My question was totally bunk.

Freiwillige & Deepo:the "stories of devastated homecoming p-47s" are at the core of the debate.
Yes, Frei, truckloads of Il2's met an untimely end. But most of that was due to their method of use. Mass raids with no fighter cover to speak of into the teeth of highly motivated veteran LW pilots. (like the Fairy Battle in France)

The FACT remains that no other fighter had a return per sortie rate coming even close the Jug. I am at work so I don't have my pile of Jug books in front of me to provide a chart.
BUT, a quick search produces the following from the Millville Army Airfield website:
<span class="ev_code_YELLOW">546,000 combat sorties with a combat loss rate of only 0.7 percent.</span>

Based on a production run of 15683, that makes for a COMBAT loss of 110 planes. (this seems low to me)

horseback
08-05-2009, 08:20 AM
Loss rate of 0.07% results in 7 losses per 1000 sorties.

That means 3822 combat losses overall. That translates into at least fifteen hundred fatalities, if a ratio of 3 successful bailouts for every five aircraft lost holds. In combat, 'safety' is a relative term.

About those 'turbine blades': the turbine was mounted in the bottom rear of the aircraft, and I believe that the fan was semiflush with the rear 'keel'. If the (rather small) fan blades broke loose and flew out along the (geometric) plane that they spun, they'd be very unlikely to hit any part of the aircraft.

Those turbine blades are in no way comparable to the turbine blades we normally think of in modern jet aircraft. They were not as big, they didn't spin perpendicular to the fuselage and I doubt that they spun as fast.

cheers

horseback

BRASSTURTLE
08-05-2009, 08:52 AM
Thanks Horseback. I thought my math was off.
3822 seems much more reasonable.

Still, I can think of no other fighter (or bomber) used in WWII that had so low a loss rate.

JtD
08-05-2009, 09:11 AM
Originally posted by ImpStarDuece:


Quite curious. What "unessential technical gadgets and functions" did the FW-190 have?

A ton. That's about the weight difference to the La-5. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

On a more serious note, there are things like the Kommandogerät, ammo counters or smooth covers for unfinished surfaces. All useful to some degree, but not essential.

JtD
08-05-2009, 09:12 AM
Originally posted by BillSwagger:

Exhaust vapor is already really hot, and even with a rich mixture, it being a high octane gas will burn a majority of the gas by the time it gets to the inter cooler.

There's no oxygen to keep the combustion going. For the same reason you can sometimes see flames shooting out of the exhausts.

na85
08-05-2009, 10:04 AM
Well Bill you're fitting in quite well here.

It seems you really just started this thread to have people confirm your preconceived notions and ideas.

Enjoy it. I wash my hands of this thread.

BillSwagger
08-05-2009, 10:27 AM
Originally posted by na85:
Well Bill you're fitting in quite well here.

It seems you really just started this thread to have people confirm your preconceived notions and ideas.

Enjoy it. I wash my hands of this thread.

Fine by me.
Not sure what your issue is, i thought we were having a good discussion.

Viper2005_
08-05-2009, 01:57 PM
Originally posted by BillSwagger:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by na85:
Hot anything can ignite gasoline fumes. Gasoline, like any other fuel, has a spontaneous combustion temperature, and if that temperature is exceeded, then fire starts.



yes, but heated metal isn't hot enough.
You can try it. (you didnt here it from me), but take a cup of high octane gas 107 rated, and heat up a chunk of metal, like a large wrench until its red hot. Then dunk it in the gasoline.
No fire...lots of potent vapor, but no fire.
http://i145.photobucket.com/albums/r201/spre77/books_002.jpg </div></BLOCKQUOTE>
The auto ignition temperature of gasoline is about 450ºC:
http://www.conocophillips.co.u...AviationGasoline.pdf (http://www.conocophillips.co.uk/EN/fuels/productinfo/documents/AviationGasoline.pdf)
http://glennoil.com/msds/avgas100LL.pdf

This is in the red hot range.

You may get away with this sort of stunt a few times, but it's not safe. If you dump the hot metal into the liquid gasoline then it will rapidly cool, which means that provided nothing else ignites the vapour produced you'll probably be ok. However, if you were to hold the hot metal over the gasoline where it can just heat the vapour, then you'd have a pretty good chance of starting a fire in a few minutes.

Originally posted by BillSwagger:
Exhaust vapor is already really hot, and even with a rich mixture, it being a high octane gas will burn a majority of the gas by the time it gets to the inter cooler.
I don't understand this at all. The definition of a rich mixture is that there is insufficient oxygen for complete combustion.


Originally posted by BillSwagger:
Part of the problem with a damaged duct, is the hot fumes are now pouring into other parts of the plane exposing them to higher temperatures than what they are designed for. (this is whats described in the test) Some parts even smolder and smoke as they burn, but there is no actual open flame. The oil cooler is the only part i see as a true fire hazard, and even that would need an ignition source.

Given time, smoke generally leads to fire. In any case, aluminium aeroplanes really don't like getting hot; hence the considerable structural damage done to the P-47 in the test I linked to.

M_Gunz
08-05-2009, 03:03 PM
It only takes one tiny spark to set off gas fumes. You can put a cigarette out in it but drop the same cig on the
floor near the same puddle and let there be one little spark and you have a fire, been here and seen it demonstrated.

Rich exhaust mixing with fresh air does burn, at night the blue flames at the ends of exhaust pipes show that.
Hole in the ducting, exhaust at high temperature meets fresh air inside the fuselage, what you think you get?

BillSwagger
08-05-2009, 03:14 PM
Originally posted by Viper2005_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BillSwagger:


yes, but heated metal isn't hot enough.
You can try it. (you didnt here it from me), but take a cup of high octane gas 107 rated, and heat up a chunk of metal, like a large wrench until its red hot. Then dunk it in the gasoline.
No fire...lots of potent vapor, but no fire.

The auto ignition temperature of gasoline is about 450ºC:
http://www.conocophillips.co.u...AviationGasoline.pdf (http://www.conocophillips.co.uk/EN/fuels/productinfo/documents/AviationGasoline.pdf)
http://glennoil.com/msds/avgas100LL.pdf

This is in the red hot range.

You may get away with this sort of stunt a few times, but it's not safe. If you dump the hot metal into the liquid gasoline then it will rapidly cool, which means that provided nothing else ignites the vapour produced you'll probably be ok. However, if you were to hold the hot metal over the gasoline where it can just heat the vapour, then you'd have a pretty good chance of starting a fire in a few minutes.
</div></BLOCKQUOTE>
indeed the vapor would be dangerous, one spark and its poof, but hot metal isn't going to ignite gas nor will it ignite exhaust fumes.

Here's the interesting part, the hot metal can ignite paper, which will ignite the gasoline.
There is a word for it in science, like a catalyst.




<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BillSwagger:
Exhaust vapor is already really hot, and even with a rich mixture, it being a high octane gas will burn a majority of the gas by the time it gets to the inter cooler.
I don't understand this at all. The definition of a rich mixture is that there is insufficient oxygen for complete combustion.
</div></BLOCKQUOTE>
It would require an overly rich mixture to have combustible fumes leading out the exhaust pipe.
You would suffer engine performance. Auto rich, will ensure enough fuel is getting into the engine to maximize performance, but won't over do it.
Even if the mixture is on the rich side, the exhaust fumes are also depleted of oxygen, and also very rich in other carbons that would choke any combustion.
I know that sometimes you can see fire shooting out of a short tail pipe, but if exaust fumes were combustible then fire would be shooting out of the pipes like a flame thrower.
The other thing to keep in mind is that the fuel mixture undergoes compression in the engine which greatly reduces its ignition temperature.
By the time it leaves the engine as exhaust, it is basically inert, as a whole. There are actually some turbo systems that reuse exhaust by cooling and filtering out the carbons.

The main problem is that exhaust is hot. Having it pour out of a hole in a duct will expose other parts to heat that they probably weren't intended for.

The structure of the airplane would not be compromised but other moving parts, like pulleys, gaskets or anything requiring oil or grease for lubrication that subsequently gets burned away, would be in danger of failing.

What's interesting about that test, is that it has nothing to do with the failure of the turbo system. The exhaust manifold was broken and caused it to pour heat into an already hot area of the plane. The firewall insulated it, but was not enough to keep from frying a gasket and damaging the rudder pulley.

BillSwagger
08-05-2009, 03:22 PM
Originally posted by M_Gunz:
Hole in the ducting, exhaust at high temperature meets fresh air inside the fuselage, what you think you get?

If the mixture were rich enough. I just don't see it happening that way. If the hole in the ducting also destroyed the firewall and matting that keeps the exhaust at bay, then i'd say you'd have bigger problems, and fire dangers would be a normal part of any emergency procedure.


During high performance demand like WEP, the pilot opens the waste gates, so the exhaust goes out the front of the plane.
I'm not sure it would even be an issue under auto rich settings.
while cruising, there's a tendency to lean out the mixture, so having an overly abundant rich exhaust inside the turbo system is probably not very likely under normal combat procedure.

deepo_HP
08-05-2009, 05:31 PM
Originally posted by BillSwagger:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Viper2005_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BillSwagger:


yes, but heated metal isn't hot enough.
...
The auto ignition temperature of gasoline is about 450ºC:
...

This is in the red hot range.
</div></BLOCKQUOTE>
indeed the vapor would be dangerous, one spark and its poof, but hot metal isn't going to ignite gas nor will it ignite exhaust fumes.

Here's the interesting part, the hot metal can ignite paper, which will ignite the gasoline.
There is a word for it in science, like a catalyst.
</div></BLOCKQUOTE>

the 'autoignition'-temp (as posted by viper) is 450C. this means, at that temperature the matter will self-ignite. the flash-point is around -12C, the fire-point a bit higher.

red hot metal is between 500-800C, any matter with a lower ignition-point will burn if enough oxygen is there, and the temperature stays long enough to deliver heat above the flash-/fire-point.
in case of already hot gas-fumes, there is no doubt, that red hot metal will ignite it.

as viper said, the only case, where it won't perhaps lead to ignition is rapid cool-down of the igniting source.
for gases with enough oxygen this won't save the situation.

no other 'word for it in science' needed.


ps:
paper has an auot-ignition point of 170-320C, so it will just ignite earlier than petrol. there is not at all any catalyst reaction here!

Bremspropeller
08-05-2009, 05:51 PM
You'd better not argue with Viper - he's chemically/ fluiddynamicly gonna jump in ya face with his bare, naked ar$e. http://forums.ubi.com/images/smilies/59.gif

deepo_HP
08-05-2009, 05:59 PM
i didn't argue him - in opposite.

i wouldn't want to get ignited by his... his bottom http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

M_Gunz
08-05-2009, 07:55 PM
Igniting paper... how many have read or watched Fahrenheit 451?

Viper2005_
08-05-2009, 08:00 PM
Originally posted by BillSwagger:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Viper2005_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BillSwagger:
yes, but heated metal isn't hot enough.
You can try it. (you didnt here it from me), but take a cup of high octane gas 107 rated, and heat up a chunk of metal, like a large wrench until its red hot. Then dunk it in the gasoline.
No fire...lots of potent vapor, but no fire.

The auto ignition temperature of gasoline is about 450ºC:
http://www.conocophillips.co.u...AviationGasoline.pdf (http://www.conocophillips.co.uk/EN/fuels/productinfo/documents/AviationGasoline.pdf)
http://glennoil.com/msds/avgas100LL.pdf

This is in the red hot range.

You may get away with this sort of stunt a few times, but it's not safe. If you dump the hot metal into the liquid gasoline then it will rapidly cool, which means that provided nothing else ignites the vapour produced you'll probably be ok. However, if you were to hold the hot metal over the gasoline where it can just heat the vapour, then you'd have a pretty good chance of starting a fire in a few minutes.
</div></BLOCKQUOTE>
indeed the vapor would be dangerous, one spark and its poof, but hot metal isn't going to ignite gas nor will it ignite exhaust fumes. </div></BLOCKQUOTE>
I've just given you the auto-ignition temperature from 2 sources which agree to within 10ºC. Above said temperature, hot metal will set the fuel on fire.

http://en.wikipedia.org/wiki/Autoignition_temperature


Originally posted by BillSwagger:
Here's the interesting part, the hot metal can ignite paper, which will ignite the gasoline.
There is a word for it in science, like a catalyst.
Nope. A catalyst is not consumed.

http://en.wikipedia.org/wiki/Catalyst



<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BillSwagger:
Exhaust vapor is already really hot, and even with a rich mixture, it being a high octane gas will burn a majority of the gas by the time it gets to the inter cooler.
I don't understand this at all. The definition of a rich mixture is that there is insufficient oxygen for complete combustion.
</div></BLOCKQUOTE>
It would require an overly rich mixture to have combustible fumes leading out the exhaust pipe.
You would suffer engine performance. Auto rich, will ensure enough fuel is getting into the engine to maximize performance, but won't over do it.[/quote]

Mixtures of fuel and air are either Lean (excess air), Stoichiometric (just right) or Rich (excess fuel).

Most piston engines will actually develop maximum power with a rich mixture for several reasons.

1) Poor mixture distribution means that to be certain of getting enough fuel to the leanest cylinder you need to run rich overall.
2) Although the adiabatic flame temperature of a rich mixture will be less than that of a stoichiometric mixture, the total quantity of heat released (delta Q) is actually greater because incomplete combustion completes the most energetically favourable reactions preferentially. For this reason, the exhaust consists CO, H2O and some soot ( C ), rather than CO2, H2O and unburnt fuel.
3) The lower flame temperature associated with a rich mixture is easier on the engine, and tends to mitigate against detonation. This allows the engine to run at higher boost and rpm than would be possible with a stoichiometric mixture.

Auto Rich is intended to run slightly on the rich side of the max power mixture, since this is inherently safe; running the engine slightly richer than the ideal (still rich) mixture for maximum power means that a small metering error will not lead to detonation. It's a compromise in the sense that if the pilot were to manually adjust the mixture to perfection then he could probably get a few % improvement in both power and sfc - but that would be a full-time job. Of course, the big piston engined airliners actually employed a flight engineer essentially for this purpose...


Originally posted by BillSwagger:
Even if the mixture is on the rich side, the exhaust fumes are also depleted of oxygen, and also very rich in other carbons that would choke any combustion.
I know that sometimes you can see fire shooting out of a short tail pipe, but if exaust fumes were combustible then fire would be shooting out of the pipes like a flame thrower.

Most people underestimate the amount of fire which actually comes out of warbird piston engine exhaust stacks, because they rarely see them running at night. Some indication is given by the large flat plates sticking out of the side of the Hurricane's cowling whose purpose is to shield the pilot's eyes from the glare of the flames when flying at night.




Originally posted by BillSwagger:The other thing to keep in mind is that the fuel mixture undergoes compression in the engine which greatly reduces its ignition temperature. Close this book and never open it again.

Compression heats the charge. It's pretty trivial to calculate how much:

http://www.grc.nasa.gov/WWW/K-...irplane/compexp.html (http://www.grc.nasa.gov/WWW/K-12/airplane/compexp.html)

The R-2800 has a compression ratio of 6.75:1

Therefore, taking gamma to be 1.4, and assuming isentropic compression, the temperature ratio between BDC and TDC is given by

((6.75/1)^1.4)^(1-(1/1.4)) ~ 2.15

Remember that this temperature ratio applies to the absolute temperature.

Assuming that the turbocharger and supercharger deliver air to the piston engine at about 120ºC, or 393.15 K, the temperature at TDC will be about 844 K, or 571ºC if you prefer. This is over the autoignition temperature of the fuel, which is why you can't run high boost at low rpm; heat the mixture to this sort of temperature and after the ignition delay has elapsed it will burn.

In fact you can ballpark the temperature at entry to the piston engine by calculating the pressure ratio between the ram pressure in the intake and the manifold pressure, and applying a sensible isentropic efficiency factor (75-80% or so for this technology level). If you want to perform the calculation yourself then I'm quite happy to check it. Otherwise I can take you through it in another post later if you want.


Originally posted by BillSwagger:By the time it leaves the engine as exhaust, it is basically inert, as a whole. There are actually some turbo systems that reuse exhaust by cooling and filtering out the carbons. Ah yes, the joys of EGR. This applies to modern engines which operate in a rather different manner from WWII vintage aero engines. Modern spark ignition engines operate at a stoichiometric mixture ratio all the time to permit the use of a 3 way catalytic converter. Meanwhile modern compression ignition engines (which tend to have more need of a particle trap than spark ignition engines) always run lean anyway. As such, they will usually have an inert exhaust (though they will burn rich periodically to clean out the particle trap).


Originally posted by BillSwagger:The main problem is that exhaust is hot. Having it pour out of a hole in a duct will expose other parts to heat that they probably weren't intended for.

The structure of the airplane would not be compromised

Homework assignment for you - look up the maximum safe operating temperature for a structure made of a 2000 series Aluminium alloy. Compare and contrast this with the exhaust temperature from a piston engine like the R-2800...


Originally posted by BillSwagger:but other moving parts, like pulleys, gaskets or anything requiring oil or grease for lubrication that subsequently gets burned away, would be in danger of failing.

What's interesting about that test, is that it has nothing to do with the failure of the turbo system. The exhaust manifold was broken and caused it to pour heat into an already hot area of the plane. The firewall insulated it, but was not enough to keep from frying a gasket and damaging the rudder pulley.

It's nothing to do with the turbo system from a GE perspective since the turbocharger itself was not at fault, but of course in the absence of a turbocharger the exhaust ducting wouldn't have been there to fail.

BillSwagger
08-05-2009, 10:43 PM
my understanding is that you see fire coming out of tail pipes because the fuel is still burning as its being pushed out of the engine.

Could you reignite exhaust with a match?

M_Gunz
08-05-2009, 11:11 PM
It's unburned gases getting enough oxygen to finish burning. Carbon monoxide at high temperature will burn to form
carbon dioxide in the presence of air, that's a feature of wood and coal burning stoves since wayyyyy back, the
re-burn chamber. It works even better when you have a platinum screen acting as a catalyst in the flow but at high
temperature it's not necessary. And yeah, I've run two different coal furnaces before and adjusted air flows below
and above, it was an educating experience. One we tore down to replace with the other bigger one and there was no
catalytic element in it.

BillSwagger
08-05-2009, 11:46 PM
so when exhaust hits fresh air again it should continue to burn?

M_Gunz
08-06-2009, 12:55 AM
It does when it's hot enough, you just don't always see the flame. At night with too rich a mix they are yellow
and adjusted back they are blue. Night fighter pilots look for the blue flames, not easy to see in blackness.

deepo_HP
08-06-2009, 01:25 AM
as m_gunz said:
'No night flying was attempted as the exhaust flames from the turbo supercharger preclude any possibility of the aircraft being used as a night fighter.'

http://www.wwiiaircraftperform...p-47/p-47c-afdu.html (http://www.wwiiaircraftperformance.org/p-47/p-47c-afdu.html)

Viper2005_
08-06-2009, 02:21 AM
Originally posted by BillSwagger:
my understanding is that you see fire coming out of tail pipes because the fuel is still burning as its being pushed out of the engine.
This is much of a muchness.

Combustion is a complicated business.

You don't just go from 2C8H18 + 25O2 straight to 16CO2 + 18H2O (complete combustion of octane). There is a whole series of complicated intermediate steps.

Generally speaking these chemical reactions never quite finish because of their sheer scale.

Avogadro's number is 6.022*10^23.

The molar mass of octane is 26. Every 26 g of octane therefore contains Avogadro's number of molecules, which I think we can agree is a lot.

As such, the chances of the last Oxygen molecule finding the last Carbon atom are remote. You get 99.999...% of the way to complete combustion, but you'll never achieve perfection in that sense.

However, because you'll generally run a WWII piston engine rich when looking for high power this is (even more) academic as combustion cannot be completed within the cylinder for want of sufficient oxygen to do the job. Since the exhaust is generally rather hot, as soon as it comes into contact with the air the products of incomplete combustion will merrily set about completing the process.

This paper gives quite a nice indication of how rich you'd tend to want to run for maximum power:

http://naca.central.cranfield....46/naca-rm-e6j08.pdf (http://naca.central.cranfield.ac.uk/reports/1946/naca-rm-e6j08.pdf)
You will note incidentally that this paper deals with pre-ignition limited performance, giving you further proof should you require it that hot metal is quite able to start fires...

It's not uncommon to see WWII fighters trailing a fair amount of soot in their exhaust as a result of running so rich, even at modern airshow power settings.

Indeed, you can sometimes read about this exhaust smoke in encounter reports as the German pilot who has just been "encountered" firewalls his throttle and dives away. Throw in the fact that rookies tend to shoot from excessive range, alerting their would-be prey with tracer, and it's easy to see how over-claiming could result (on both sides, human nature and thermodynamics been constant), especially because exhaust smoke always looks much thicker from in front or behind...


Originally posted by BillSwagger:Could you reignite exhaust with a match?

If you were to collect them, cool them, mix them with sufficient air to complete combustion and then apply the match, I suppose you could.

Bremspropeller
08-06-2009, 04:20 AM
That wasn't directed at you, deepo http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

M_Gunz
08-06-2009, 04:32 AM
Originally posted by deepo_HP:
as m_gunz said:
'No night flying was attempted as the exhaust flames from the turbo supercharger preclude any possibility of the aircraft being used as a night fighter.'

http://www.wwiiaircraftperform...p-47/p-47c-afdu.html (http://www.wwiiaircraftperformance.org/p-47/p-47c-afdu.html)

Where did I write that? AFDU did, not me, I didn't even know about that with P-47's!
There's other planes that made the blue flames, like RAF and Luftwaffe bombers on night missions.

BillSwagger
08-06-2009, 06:17 AM
Everything Viper has described makes sense and is a lot more thorough than my descriptions.

I'm trying to gain a better understanding of how the exhaust going through the duct is flammable.
I know that once combustion is completed then it goes through the ducting, but unless its thoroughly mixed and cooled with fresh air, then exhaust is not flammable?

Viper2005_
08-06-2009, 06:57 AM
The exhaust is flammable, and if it is mixed with sufficient air and a source of ignition then a fire will result.

You wouldn't be able to light it with a match unless you cooled it and then mixed it with air because:

Hot exhaust (fuel) + air (oxidiser) = fire without a match.

Combustion isn't completed when the exhaust leaves the piston engine; it has just stopped for want of oxygen. The exhaust probably contains plenty of carbon monoxide and unburnt hydrocarbons, both of which will burn if given the chance.

If you supply supply oxygen whilst the exhaust is still hot enough to burn then the combustion will start up again and proceed to completion.

"Carbon monoxide does support combustion and burns with a pale blue flame. The blue flame used to be seen over the fires made from coke (essentially a very pure form of carbon) by night watchmen on industrial sites."
http://www.chm.bris.ac.uk/motm/co/coh.htm

Carbon monoxide was probably the source of the pale blue exhaust flame seen by nightfighter pilots.