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Hristos
04-21-2005, 12:39 AM
so ? http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

FA_Whisky
04-21-2005, 01:29 AM
it will never be there......

Hristos
04-21-2005, 02:04 AM
hmm, somehow I feel I'd win the bet http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

LeadSpitter_
04-21-2005, 02:06 AM
forget the mk III will the p38 p47 p51b c d be getting the much needed boost

Dolemite-
04-21-2005, 02:17 AM
How many more patches do you think we'll get after patch 4.0?
and I mean FB-AEP.

Someday the patches will have to stop right? No new planes no new anying... It must end sometime...

robban75
04-21-2005, 02:23 AM
Forgive me for asking, but why does the P-38 and P-47 need a boost? They both show excellent performance when I have done my testing with them. The P-51B/C needs a little more speed, but that's it IMO.

Hristos
04-21-2005, 02:37 AM
The thing does almos 400 mph on the deck. About 640+ kph.

So, there must be a drawback. Is there any ?

robban75
04-21-2005, 03:21 AM
I'm ok with the Mustang MkIII, I was just curious as to what's wrong with the current performance of the P-38 and P-47. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

WOLFMondo
04-21-2005, 03:22 AM
Hristos, stop spreading rumourshttp://forums.ubi.com/groupee_common/emoticons/icon_wink.gif.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by LeadSpitter_:
forget the mk III will the p38 p47 p51b c d be getting the much needed boost <HR></BLOCKQUOTE>

Why? The only plane there that needs a boost that hasn't got one is the P38. The rest of them have there boosts already at the right levels. The only other allied plane I can think of that needs a higher boost level is the Spitfire IX from 44 onwards.

The Mustang MkIII got its 25lbs boost for specific reasons and was in operation with the RAF. Most were PR planes anyways AFAIK.

LeadSpitter_
04-21-2005, 04:15 AM
robban75 show some 3.04 tracks of all the allied ac's top speeds.

I seen your screens of the mustang doing 610kmph i believe 590kmph same with all your p38 p47 screens on crimea but they are obviously from many patchs ago.

All your german screens im able to achieve those speed no problem 570 for the a4-a6 580-590 a8 a9 f8 using 103 trottle rad8 for the 190as with never overheat.

With the 109g6 540kmph using 105 trottle and auto/manual rad with no overheat ever, then with porpoising the ac you can get an extra 10-20kmph.

Care to show tracks in 3.04 that match the screenshot speeds you shown if you have the time I would love to see them.

Thx if you have the time to show them

robban75
04-21-2005, 05:40 AM
I managed to get 595km/h with the Mustang with this patch, IIRC lrrp did it too, or maybe it was 593km/h.

For the P-47D-27 I got 578km/h, and with the P-38J I got 582, the L only reached 572. Strange cause it's a later war fighter than the J.

IMO anyone should be able to reach these speeds. But it takes time no doubt. I think people just give up too soon.

Just did some freshly made speed runs!

I just need your email adress, Lead. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

Write to my email adress, robbanwesterberg@hotmail.com

Vipez-
04-21-2005, 08:39 AM
I think P38J was slightly faster , than P38L early at sealevel.. btw. Rumor is we will be getting P38 Late in 4.0... http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Diablo310th
04-21-2005, 08:53 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by LeadSpitter_:
forget the mk III will the p38 p47 p51b c d be getting the much needed boost <HR></BLOCKQUOTE>

I'm with you LS....since I can't have a P-47N give me a D-27 with 72" boost...yeehaww look out Dora's. I'll wave as I go past ya after putting a couple .50 cal holes in ya. http://forums.ubi.com/images/smilies/mockface.gif http://forums.ubi.com/images/smilies/784.gif

lrrp22
04-21-2005, 08:57 AM
Yep, I can get 593-594 kph out of the P-51D at 100% fuel. Interestingly, I can only get around 592 kph at 25% fuel!

If Robban says airplane 'X' does speed 'Y' at altitude 'Z', you can bet that it does.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by robban75:
I managed to get 595km/h with the Mustang with this patch, IIRC lrrp did it too, or maybe it was 593km/h.

<HR></BLOCKQUOTE>

lrrp22
04-21-2005, 09:00 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hristos:
The thing does almos 400 mph on the deck. About 640+ kph.

So, there must be a drawback. Is there any ? <HR></BLOCKQUOTE>

Nope... http://forums.ubi.com/images/smilies/784.gif http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Hristos
04-21-2005, 09:10 AM
I guess I'll have to ask uncle Willi for help http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

horseback
04-21-2005, 09:39 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> I guess I'll have to ask uncle Willi for help <HR></BLOCKQUOTE>

Uncle Kurt not answering your calls any more?

cheers

horseback

p1ngu666
04-21-2005, 09:43 AM
only has 4 .50cals
but yes, lots and lots of speed http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

VW-IceFire
04-21-2005, 09:43 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by robban75:
I managed to get 595km/h with the Mustang with this patch, IIRC lrrp did it too, or maybe it was 593km/h.

For the P-47D-27 I got 578km/h, and with the P-38J I got 582, the L only reached 572. Strange cause it's a later war fighter than the J.

IMO anyone should be able to reach these speeds. But it takes time no doubt. I think people just give up too soon.

Just did some freshly made speed runs!

I just need your email adress, Lead. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

Write to my email adress, robbanwesterberg@hotmail.com <HR></BLOCKQUOTE>
The P-38L was a bit heavier than the P-38J and the J was indeed faster than the L. There was also apparently some minor issues caused by the dive flaps extending on their own or hanging slightly loose causing drag.

There was a later variant of the P-38L with a higher rated Allison engines. There are rumors about that one being made available.

faustnik
04-21-2005, 09:46 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by LeadSpitter_:

All your german screens im able to achieve those speed no problem 570 for the a4-a6 580-590 a8 a9 f8 using 103 trottle rad8 for the 190as with never overheat.
<HR></BLOCKQUOTE>

Leadspitter,

Could you please post or send me the track of the Fw190A4 doing 570 kph at 103% throttle. That's impressive speed to get out of the A4!

robban75
04-21-2005, 09:49 AM
Thanks for the info IceFire! http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

And thanks for the kind words lrrp! http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

Hristos
04-21-2005, 10:16 AM
4 .50 cals might be its Achilles' heel. But still, a very nasty opponent.

It will surely be interesting to see which planes will become darling aircraft of 4.0 http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

P.S.
Uncle Kurt is busy with Ta 183, so uncle Willi has to jump in with 262.

lrrp22
04-21-2005, 10:52 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hristos:
...so uncle Willi has to jump in with 262. <HR></BLOCKQUOTE>

Jeez...the Mk. III doesn't seem so nasty when you put it that way! http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

p1ngu666
04-21-2005, 11:32 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by faustnik:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by LeadSpitter_:

All your german screens im able to achieve those speed no problem 570 for the a4-a6 580-590 a8 a9 f8 using 103 trottle rad8 for the 190as with never overheat.
<HR></BLOCKQUOTE>

Leadspitter,

Could you please post or send me the track of the Fw190A4 doing 570 kph at 103% throttle. That's impressive speed to get out of the A4! <HR></BLOCKQUOTE>

190 is also looses very little speed from having drop tanks on, i was quite surprised http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

ColoradoBBQ
04-21-2005, 11:37 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hristos:
The thing does almos 400 mph on the deck. About 640+ kph.

So, there must be a drawback. Is there any ? <HR></BLOCKQUOTE>

If you sneeze, you'll lose your wings.

faustnik
04-21-2005, 11:46 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by p1ngu666:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by faustnik:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by LeadSpitter_:

All your german screens im able to achieve those speed no problem 570 for the a4-a6 580-590 a8 a9 f8 using 103 trottle rad8 for the 190as with never overheat.
<HR></BLOCKQUOTE>

Leadspitter,

Could you please post or send me the track of the Fw190A4 doing 570 kph at 103% throttle. That's impressive speed to get out of the A4! <HR></BLOCKQUOTE>

190 is also looses very little speed from having drop tanks on, i was quite surprised http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif <HR></BLOCKQUOTE>

And you can do some fast rolling with an SC500 strapped on. Hard to believe you could do much rolling with an extra 1100 lbs. strapped on the bottom of the plane.

The Spitfire has some similar issues. The Mk IX gets its full maximum test speed on the deck. Those tests were done with the radiator locked in closed position. In the sim however, the radiator must be open because the Spit IX never overheats at low level at full WEP, but the Spit still gets full tested speed. So, there seem to be some issues with added drag on aircraft.

I'd still like to see that 570kph speed for the Fw190A4 at 103%.

*****************

Of course every other prop plane will be slow compared to the MkIII. http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

Aaron_GT
04-21-2005, 12:18 PM
"Hard to believe you could do much rolling with an extra 1100 lbs. strapped on the bottom of the plane."

It's near the centre of rotation so shouldn't be that much of a problem, as long as the shackles are sufficient to hold it in place.

p1ngu666
04-21-2005, 12:25 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by faustnik:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by p1ngu666:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by faustnik:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by LeadSpitter_:

All your german screens im able to achieve those speed no problem 570 for the a4-a6 580-590 a8 a9 f8 using 103 trottle rad8 for the 190as with never overheat.
<HR></BLOCKQUOTE>

Leadspitter,

Could you please post or send me the track of the Fw190A4 doing 570 kph at 103% throttle. That's impressive speed to get out of the A4! <HR></BLOCKQUOTE>

190 is also looses very little speed from having drop tanks on, i was quite surprised http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif <HR></BLOCKQUOTE>

And you can do some fast rolling with an SC500 strapped on. Hard to believe you could do much rolling with an extra 1100 lbs. strapped on the bottom of the plane.

The Spitfire has some similar issues. The Mk IX gets its full maximum test speed on the deck. Those tests were done with the radiator locked in closed position. In the sim however, the radiator must be open because the Spit IX never overheats at low level at full WEP, but the Spit still gets full tested speed. So, there seem to be some issues with added drag on aircraft.

I'd still like to see that 570kph speed for the Fw190A4 at 103%.

*****************

Of course every other prop plane will be slow compared to the MkIII. http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif <HR></BLOCKQUOTE>

i just ment speed, its pretty lively still with tanks on the wings too.

mkIII will be fastest down low, think only tempest will rival it, think even mossie will not be as fast http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

Slickun
04-21-2005, 12:41 PM
The Mark III, Spit 14 (modified for 150 octane) and the Tempest were all clocked within a few mph of each other on the deck. Mustang fastest dead on the deck, but as the altitude rose all three types surged past the other, just to fall back again a few thousand feet higher.

Anybody got that graph? Its pretty well known. All three types could really go.

lrrp22
04-21-2005, 12:51 PM
Slickun,

The Spit XIV's speed in AVIA 6/10618 represents +25 lbs boost which the Spit XIV was never cleared for. Even at +21 lbs on 100/150 grade fuel, the Mk. XIV is going to be around 20 mph slower at lower altitudes than the +25 lbs boost Mustang and +11 lbs Tempest.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Slickun:
The Mark III, Spit 14 (modified for 150 octane) and the Tempest were all clocked within a few mph of each other on the deck. Mustang fastest dead on the deck, but as the altitude rose all three types surged past the other, just to fall back again a few thousand feet higher.

Anybody got that graph? Its pretty well known. All three types could really go. <HR></BLOCKQUOTE>

faustnik
04-21-2005, 12:54 PM
I'm really looking forward to B&Zing the cr4p out of those Bf109s. http://forums.ubi.com/images/smilies/icon_twisted.gif

lrrp22
04-21-2005, 01:20 PM
A +25 lbs boost Mustang III's sustained climb shouldn't be too shabby, either. P-51B-15-NA 43-24777, at 9,650 lbs and full internal fuel w/wing racks, reached just under 4400 fpm at 2200 ft on +22 lbs boost.

At +25 lbs boost and 25-50% fuel a Mustang III's climb should be rather impressive... http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by faustnik:
I'm really looking forward to B&Zing the cr4p out of those Bf109s. http://forums.ubi.com/images/smilies/icon_twisted.gif <HR></BLOCKQUOTE>

RedNeckerson
04-21-2005, 01:31 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hristos:
The thing does almos 400 mph on the deck. About 640+ kph.

So, there must be a drawback. Is there any ? <HR></BLOCKQUOTE>


In the sim, probably not.

In real life, most definitely.

faustnik
04-21-2005, 01:36 PM
Why would there be any "drawbacks"? The MkIII used the same engine as previous versions, just added boost. Same weight + more power = more better. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif


(I take that back, drawbacks would be decreased engine life and possibly more heat at full boost.)

lrrp22
04-21-2005, 01:47 PM
The only problems encountered in real life were increased spark plug fouling, higher fuel consumption at the higher WEP setting, and decreased engine life.

As for flight performance- there were no trade off's. It retained all its altitude performance while greatly increasing performance below 20,000 ft.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by RedNeckerson:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hristos:
The thing does almos 400 mph on the deck. About 640+ kph.

So, there must be a drawback. Is there any ? <HR></BLOCKQUOTE>


In the sim, probably not.

In real life, most definitely. <HR></BLOCKQUOTE>

bolillo_loco
04-21-2005, 02:07 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by VW-IceFire:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by robban75:
I managed to get 595km/h with the Mustang with this patch, IIRC lrrp did it too, or maybe it was 593km/h.

For the P-47D-27 I got 578km/h, and with the P-38J I got 582, the L only reached 572. Strange cause it's a later war fighter than the J.

IMO anyone should be able to reach these speeds. But it takes time no doubt. I think people just give up too soon.

Just did some freshly made speed runs!

I just need your email adress, Lead. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

Write to my email adress, robbanwesterberg@hotmail.com <HR></BLOCKQUOTE>
The P-38L was a bit heavier than the P-38J and the J was indeed faster than the L. There was also apparently some minor issues caused by the dive flaps extending on their own or hanging slightly loose causing drag.

There was a later variant of the P-38L with a higher rated Allison engines. There are rumors about that one being made available. <HR></BLOCKQUOTE>

I really do get tired of watching this rumor get passed on from forum to forum. Can somebodly please explain why the J and L would have different speeds? Since the USAAF neutered the F-30s in the L and restricted it to the same power levels of the F-17s in the J why would the J be faster?

weights........the J and L are so close in weight that the USAAF decided to lump them into the same category in the pilots manual.

empty weight P-38J 12,780
empty weight P-38L 12,800

yes I can see that running the same hp how the J would be faster considering that it is 20 lbs lighter. I mean 20 lbs on a 17,699lb fighter yes that is a rather large difference. I have noticed that amongst the people who perpetuate this rumor they seem to not read a lot on the 38 or they have forgotten what they have read. They frequently state "power boosted ailerons, dive recovery flaps tail warning radar etc" well since you do not understand how you can add things to an aircraft and not have it gain any weight I will tell you. according to the books I have read (over 40 in total on the 38 only or units that flew them) items were deleted and simplified which saved weight. just the omission of paint drops 60 lbs from the weight of the 38.

now if we are going to talk about a speed difference..... even with the hp restriction the usaaf put on the L........the fact that many J models were painted........would make them slightly slower and the L model could make sea level hp up to 28,700ft against the J models 26,500 ft.

take away the hp restriction of the L's f-30s and let them run 3,200 rpm 64" mp 1,725hp and then I will agree that there was a difference in speed with the J and L model......the L was faster.

stop the rumors, buy some books and read up on the 38.

all varients of the L model carried the F-30 and all varients of the J carried the F-17. this was allisons way of designating their engines. allison cleared the F-30 for the above mentioned power settings, but the usaaf never followed through with it to my knowledge. If somebody has some proof that I am wrong on any of what I have said, please direct me to the books and documents you have because I would like them for myself. no ulrs from web sites please. I do not care what some pimply faced kid has posted on his web site about his favorite plane. authors of books and publishing companies have their reputation and livelyhood on the line so they tend to be way more credible than some personal web site.

p1ngu666
04-21-2005, 02:16 PM
if the J and the L have same power, L has more drag, hence slower.

rumoured nice thing in patch for p38 lovers tho http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

bolillo_loco
04-21-2005, 02:20 PM
Originally posted by VW-IceFire:

The P-38L was a bit heavier than the P-38J and the J was indeed faster than the L. There was also apparently some minor issues caused by the dive flaps extending on their own or hanging slightly loose causing drag

I have addressed the speed differences already now to move on to dive recovery flaps hanging causing drag????? I have never ever read this in any book or watched any pilot talk about it in an interview. can you please direct me to this sorce of information.

Slickun
04-21-2005, 02:31 PM
Irrp, do you know th graph I'm talking about. it shows the three types all at 400 mph or so, with the Mustang screaming along at 405 mph, the Mark 14 and T5 just behind it.

I may have it somewhere.

bolillo_loco
04-21-2005, 03:04 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by p1ngu666:
if the J and the L have same power, L has more drag, hence slower.

rumoured nice thing in patch for p38 lovers tho http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif <HR></BLOCKQUOTE>

how would it have more drag? show me a graph which states this. the graphs and charts I have seen treat the J and L as the exact same aircraft. do you know why they do this? because by all external appearences they are identicle. same airframe same power ratings except at high altitude same weight. show me a source which puts the J as faster than the L with the exception of caiden's book. caidens book is the only one I am aware of. any other reference is just perpetuating caidens error.

p1ngu666 I do not see how anybody after looking at the J and L with your naked eyeball could state what you have just said. how would the J have more drage than the L? the only and I mean only external differences would be dive recovery flaps which cannot be a significant source of drag. I doubt highly that it had any impact on the top speed of the a/c. the L model would be the better stream lined of the two simply because it was finished in natural metal. most J models were painted in flat drab paint.

you must not have read a lot on the 38. I am sure you have no problem seeing the difference between 38E - 38H models and the 38J and 38L models. it is easy to spot the bearded chin inner coolers, improved radiators, and flat wind screen. this is a significant difference that the human eye can see yet the difference in drag is not real significant. at 250 mph the 38J and L have to over come 1676 lbs of drag to maintain that speed. the 38H and earlier versions have to over come 1649lbs of drag to maintain that same speed of 250 mph. 1649 vs 1676 that means that even early 38s had 98.4% as much drag at 250 mph as did later J and L models which look like they should have much more drag.

nobody can prove that the J was faster than the L. nobody can prove that the L model had more drag than the J......enough to make the J model faster than the L and do you know why this is? simple because it isnt true.

dragging out old tests proves absolutely nothing. if you compair 15 a/c that are the exact same model you will see that some will out perform others, some will be dogs......I would venture a guess that it would look similar to a bell curve.....a few dogs a few outstanding performers and the pack of average performance in the middle.

Aaron_GT
04-21-2005, 03:25 PM
"the L model would be the better stream lined of the two simply because it was finished in natural metal. most J models were painted in flat drab paint. "

Under what conditions were the factory or USAAF speed tests done? It might be that they were both done with the same paint conditions.

With regard to the dive flaps drag increases as the square of the speed, but I can only see the undeployed flaps making a very small difference.

RedNeckerson
04-21-2005, 03:35 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by lrrp22:
The only problems encountered in real life were increased spark plug fouling, higher fuel consumption at the higher WEP setting, and decreased engine life.

<HR></BLOCKQUOTE>


The "only problems encountered"??

Sorry, but this is incorrect.

Merlins running on 100/150 grade fuel and +25lbs boost suffered complete engine failure on numerous occasions.

In some cases it was valves burning out and failing, worst case is complete engine failure and best case under these circumstances is simply loss of power.

Mustangs did not run at +25lbs without 100/150 grade fuel AFAIK.

Roger Freeman's Mighty Eighth War Manual:

"Enthusiasm for the new fuel waned quickly and in the same month some units requested a return to 100/130. As the old grade had been largely replaced by 100/150, supply was difficult."


The British were apparently willing to accept their chances with 100/150 (anti- V1 missions I guess?) and experimented with different chemical solutions like less ethylene dibromide.


As far as the sim goes however, Oleg doesn't model the engine failures so there is nothing to worry about from that standpoint when the British Mustang III gets here.

p1ngu666
04-21-2005, 04:05 PM
i mean that the two p38s, assuming both are the "same" apart from the L has dive brakes and radar thingy will be abit heavier, but the main difference is the extra drag.

il2c says its 10kph at sealevel which is 6mphish?

thats a beliveable amount of speed reduction for those two things extra

lrrp22
04-21-2005, 04:31 PM
Red,

True, but Mustangs running at +18 lbs boost and 100/130 grade also suffered numerous complete engine failures- as did every other wartime fighter. Was it more prevelant at +25 lbs boost? No doubt, but not enough to be considered prohibitve.

The switch to 100/150 grade required some adjustments to be made, but made they were. Plug fouling was the primary cause of power loss at take-off, not burned-out valve seats. The replacement of valve seats and frequent adjustments to valve timing were blamed for an increased maintenance load, but not necessarily engine failures. It was the 'Pep' fuel additive that was responsible for the valve seat problems, not the 100/150 grade fuel itself. 'Pep' was added to address the plug fouling issue, but most groups preferred frequent spark plug changes to the valve maintenance issues. IIRC, Pep entered testing with the 355 FG during December of '44, six months after VIIIth FC began to implement 100/150 grade. As for plug fouling, it was found that periods of high boost/low RPM during the cruise portion of flight greatly reduced the fouling.

BTW, Freeman is referring to USAAF VIIIth Fighter Command Mustangs which never ran +25 lbs boost- they were limited to +21 lbs boost on 100/150 grade.

lrrp22
04-21-2005, 04:35 PM
Hello slickun,

Yes, I've got the entire report. The curve for the Spit XIV is mostly estimated data since the R.A.E. couldn't get the engine to run properly at +25 lbs boost. Subsequently, the Spit's Griffon 65 was never cleared for +25 lbs boost.

Here's my scan of the graph:

http://img.photobucket.com/albums/v11/brentce/AVIA6-10618fig8.jpg

Here are Rolls-Royce's speeds for the Spit 14 at +21 lbs and the Mustang III at +25:
http://www.spitfireperformance.com/spit14at21.jpg

Note the Mustang with the -7 engine: 424 MPH at 5,500 ft!


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Slickun:
Irrp, do you know th graph I'm talking about. it shows the three types all at 400 mph or so, with the Mustang screaming along at 405 mph, the Mark 14 and T5 just behind it.

I may have it somewhere. <HR></BLOCKQUOTE>

Slickun
04-21-2005, 04:45 PM
That's the one.

So, you say the Spit 14 is theoretical? That they never ran properly at the boost this graph depicts?

Interesting.

p1ngu666
04-21-2005, 04:48 PM
hm, tempests boost went to 13lbs and higher revs didnt it?

lrrp22
04-21-2005, 05:05 PM
I'll have to look at the rest of the report tonight, but IIRC the Spit XIV only generated data points at around 2,000 ft- the rest of the curve is estimates. The RAE damaged either two or three Griffon 65's during the test trying to get them to +25 lbs boost.

But yes, the Spit XIV was never allowed to run at +25 lbs boost operationally.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Slickun:
That's the one.

So, you say the Spit 14 is theoretical? That they never ran properly at the boost this graph depicts?

Interesting. <HR></BLOCKQUOTE>

faustnik
04-21-2005, 05:13 PM
Irrp,

I hate to do this to you, I know you've posted this before but...

When were the RAF Mustangs converted to +25 boost? Where did the squadrons equipped with them operate?

sry.

Slickun
04-21-2005, 05:48 PM
Thank you, Sir, for the quick answer.

Mustang operations in the RAF have always been a source of frustration to me. Alongside the questions asked by faustnik, specific to the +25 boost birds, I have never been able to find the total number of kills for RAF Mustangs. I know there were several aces. I know the RAF Pony's escorted Lancasters etc on daylight raids late in the war. Their own version of the daylight bombing campaign.

I know P-51's chased V-1's.

I'd just like to know more.

I'd like to know more about Pacific P-51 operations, and where and when high boost P-51's were operated, and when.

I'd like to know, once and for all, if the P-51H got into combat.

VW-IceFire
04-21-2005, 06:07 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by bolillo_loco:
Originally posted by VW-IceFire:

The P-38L was a bit heavier than the P-38J and the J was indeed faster than the L. There was also apparently some minor issues caused by the dive flaps extending on their own or hanging slightly loose causing drag

I have addressed the speed differences already now to move on to dive recovery flaps hanging causing drag????? I have never ever read this in any book or watched any pilot talk about it in an interview. can you please direct me to this sorce of information. <HR></BLOCKQUOTE>
I'll have to see if I can remember where I got this from. I've been reading alot about P-38s recently for my 12 mission Normandy campaign regarding them (almost finished!) and I really like the plane but you obviously sound like you know more than I do about them. Now if you asked me about the Tempest.... http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Anyways, I'll see if I can dig it up. I could have sworn I read about some issues with the dive recovery flaps.

horseback
04-21-2005, 06:22 PM
Paint, particularly matte finish paint, adds quite a bit of weight, as well as drag, to an aircraft. Obviously, the larger the aircraft, the more the paint weight penalty. While I don't know how much the paint on a P-38 weighed, I seem to recall a figure well in excess of 300 lbs (around 140 kg) for a P-47.

The P-38 was an exceptionally large (and bumpy) fighter, and extra weight and drag were things their pilots would want to avoid. That was how the manufacturers sold the natural metal finish to the government, along with the cost savings of eliminating camo paint.

It would seem to me that with the additional horsepower coupled with a NM finish, the average P-38L should probably be faster than the painted J.

cheers

horseback

RedNeckerson
04-21-2005, 08:57 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by lrrp22:
Red,

Was it more prevelant at +25 lbs boost? No doubt, but not enough to be considered prohibitve.

<HR></BLOCKQUOTE>


Yes, the way I read it was that the British were willing to accept the risks and apparently were working with different types of chemical solutions.

My understanding was this was deemed acceptable for home defence/ V1 intercept missions?

Do you know if that's correct?

I know the British were using Mustangs for escorts(but under what configuration?) when they started doing daylight raids with much more frequency, and there is a combat with FW190D-9s of JG/26 that I remember.

Other than that, I don't really know much about the actual operational history of the Mustang III.

lrrp22
04-21-2005, 09:28 PM
Red,

It seems the RAF was just more institutionally liberal with the boost it allowed (see its use of 72" Hg for up to 20 minutes in its Allison Mustangs). +25 lbs boost was cleared for all Merlin 66's and Packard Merlin V-1650-7's (ADGB ordered all V-1650-7's to be modified for +25 lbs boost on 24Aug44) whenever 100/150 grade fuel was available, and there was a lot of 150 grade produced during the last year of the war.

Apparently the USAAF's conservative approach to boost didn't extend to operations in the Pacific, though. It appears that 115/145 grade fuel and +25 lbs boost became standard for the four VIIth Figther Command groups based on Iwo Jima during early April, '45.



<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by RedNeckerson:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by lrrp22:
Red,

Was it more prevelant at +25 lbs boost? No doubt, but not enough to be considered prohibitve.

<HR></BLOCKQUOTE>


Yes, the way I read it was that the British were willing to accept the risks and apparently were working with different types of chemical solutions.

My understanding was this was deemed acceptable for home defence/ V1 intercept missions?

Do you know if that's correct?

I know the British were using Mustangs for escorts(but under what configuration?) when they started doing daylight raids with much more frequency, and there is a combat with FW190D-9s of JG/26 that I remember.

Other than that, I don't really know much about the actual operational history of the Mustang III. <HR></BLOCKQUOTE>

LeadSpitter_
04-21-2005, 10:59 PM
resdawgz@aol.com is my email address robban75, thx for taking the time to make some tracks.

lrrp22
04-21-2005, 11:38 PM
faustnik and Slickun- check your PM's...

LRRP22

WOLFMondo
04-22-2005, 01:31 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by p1ngu666:
hm, tempests boost went to 13lbs and higher revs didnt it? <HR></BLOCKQUOTE>

Tempest in the graph is using the IIA engine only seen in the first 100 in 1944. The Sabre IIB was in the majority of them and the IIC in a minority. AKAIK both ran at 13lbs on 150 grade fuel.

VW-IceFire
04-22-2005, 10:54 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by faustnik:
Irrp,

I hate to do this to you, I know you've posted this before but...

When were the RAF Mustangs converted to +25 boost? Where did the squadrons equipped with them operate?

sry. <HR></BLOCKQUOTE>
Off the top of my head...April 1944 they started converting. I think by early 1945 they were all running on the same specs.

Alot of Polish squadrons using the Mustang for low level attack from what I understand.

p1ngu666
04-22-2005, 11:03 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by VW-IceFire:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by faustnik:
Irrp,

I hate to do this to you, I know you've posted this before but...

When were the RAF Mustangs converted to +25 boost? Where did the squadrons equipped with them operate?

sry. <HR></BLOCKQUOTE>
Off the top of my head...April 1944 they started converting. I think by early 1945 they were all running on the same specs.

Alot of Polish squadrons using the Mustang for low level attack from what I understand. <HR></BLOCKQUOTE>

poor germans!
ppl from occupied countries where often noted as being very agressive in action, especialy the poles...

probably didnt give them tiffy's cos they would use the cannons to spear german stuff...

ddsflyer
04-22-2005, 01:15 PM
Manifold pressure is measured in "Hg (inches of mercury) Stock P-51 max power MP was 60"Hg (29 lbs pressure or +15 lbs boost. The only way to increase this figure is to regear the supercharger and this was never done for combat aircraft because it negatively affects reliability. +25 lbs boost would be 80"Hg, a figure never attained with combat aircraft due to this reliability factor. Modern P-51 racers such as Strega pull 90-120"Hg using N2O or Alcohol/water and changed supercharger gearing, but the engine is trash after a few runs.

lrrp22
04-22-2005, 01:45 PM
Uhhh, no... http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

First, the 'stock' combat power for the Mustang was 67" Hg/+18 lbs boost on 100/130 grade fuel. Second, with the introduction of 100/150 grade fuel in mid-1944, max permissable boost was raised to 81" Hg/+25 lbs boost for the RAF's Merlin 66/266/V-1650-7 engines. It did not require a change to the supercharger gearing since the SC was capable of producing far more boost than the lower grade fuel could sustain, hence the automatic boost control to limit max boost below rated altitude.

By mid-Aug of 44, four RAF Mustang III squadrons had recorded over 7,000 operational hours running 100/150 grade and +25 lbs boost- though obviously not at +25 lbs the whole time!



<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ddsflyer:
Manifold pressure is measured in "Hg (inches of mercury) Stock P-51 max power MP was 60"Hg (29 lbs pressure or +15 lbs boost. The only way to increase this figure is to regear the supercharger and this was never done for combat aircraft because it negatively affects reliability. +25 lbs boost would be 80"Hg, a figure never attained with combat aircraft due to this reliability factor. Modern P-51 racers such as Strega pull 90-120"Hg using N2O or Alcohol/water and changed supercharger gearing, but the engine is trash after a few runs. <HR></BLOCKQUOTE>

p1ngu666
04-22-2005, 02:22 PM
they may "only" pull 90-120Hg with water etc because 150octane fuel had alot of lead in it i think, hence people arent too happy about it being used.

the RN seafury has limited quantities of 150 because its engine needs it or something, the one that does the airshows http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

ddsflyer
04-22-2005, 03:48 PM
Apparently the RAF treated their Mustangs a lot more harshly than the USAAF did.

lrrp22
04-22-2005, 06:01 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ddsflyer:
Apparently the RAF treated their Mustangs a lot more harshly than the USAAF did. <HR></BLOCKQUOTE>

8th AAF ran its Mustangs at 72" Hg/+21 lbs boost on 100/150 grade. USAAF VIIth Fighter Command on Iwo Jima ran its Mustangs at the RAF's 81" Hg on 115/145 grade.