# What's the purpose of the P-47's protruding barrel sleeves?



## DAVIDICUS (Apr 18, 2005)

This interesting question was posed by "spaters" on the Aircraft Requests forum. There have only been a few responders and the answers have been speculative. I thought that this question would receive more proper treatment and ultimate resolution here.

What was the purpose of the leading edge protruding barrel sleeves that housed the .50 cal. gun barrels?


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## Matt308 (Apr 18, 2005)

Purely a WAG...

A: To better facilitate quick changes of the BMGs without need to perform labor and time intensive boresighting procedures that result in aircraft downtime.


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## Matt308 (Apr 18, 2005)

It appears that I may be on to something. Check out

http://rwebs.net/avhistory/history/p-47.htm

"The four .50 cal machine guns in each wing of the P-47 are secured in the gun bays to Republic-designed mounts. Front mounts are conical-shaped and the guns are locked to these by rotating the locking ring of the gun bracket assembly; the rear-mounts are locked by simple levers which are part of the rear mount assemblies."


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## DAVIDICUS (Apr 18, 2005)

Matt 308,

I don't see how the following is relevant:

"_The four .50 cal machine guns in each wing of the P-47 are secured in the gun bays to Republic-designed mounts. Front mounts are conical-shaped and the guns are locked to these by rotating the locking ring of the gun bracket assembly; the rear-mounts are locked by simple levers which are part of the rear mount assemblies_." 

The front mounts are at the front of the receiver and operate without regard to the barrel's placement within the sleeve.

The only way that the barrel sleeves could aid in maintaining the secure and accurate placement of the guns after the sighting in process would be if the sleeves themselves were adjustable to fit necessary barrel adjustments made in the sighting in process and thereafter locked into position. I don't think that this was the case.







On the other thread, I suggested that they may just be a further barrel guide for the proper placement of the barrels that may have something to do with the guns being aligned parallel to the ground as opposed to centered in the leading edge of the wing.


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## Matt308 (Apr 18, 2005)

Hey it's a WAG. Seems to me that an aircraft that was designed with ground strafing as its primary mission would also focus upon means to streamline repetative and lengthy maintenance procedures. While I understand your point about the front mounts as being universal, it seems odd that these were noted as Republic's design. US military, being the fanatics for standards that they are, would likely spec a common locking ring for all .50 BMG unless perhaps Republic was on to something. The note about the rings being conical implies to me that perhaps the BMGs were being 'funneled' into a set alignment. Otherwise a simple locking ring with windage and elevation would have sufficed. In fact, if you designed a 4 gun carriage, you might be able to make a single adjustment to the carriage and simply insert the BMGs.  Sounds reasonable. This might have been born of necessity since boresighting for windage and elevation for six BMGs was bad enough...but eight!?

Didn't the F9F panther have these sleeves too?


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## Matt308 (Apr 18, 2005)

Davidicus,

I searched my information on F9F and I can't dig up anything similar for its four 20mm. Must be my youthful imagination.

I would love to hear others thoughts, as I don't profess my response to be anything more than educated guess.


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## DAVIDICUS (Apr 18, 2005)

Hey Matt308, can you pay a visit to the OFF-Topic / Misc. forum? I have a question about Washington.


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## DAVIDICUS (Apr 19, 2005)

Does anyone have any information to add to this topic?

PBAILLON's spastic posting of topics unrelated to this forum is displacing current, active posts on the first page and relegating them to the second page where they don't benefit from exposure.


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## Jank (Apr 21, 2005)

Did they have vents? Were they to help the cooling?


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## DAVIDICUS (Apr 24, 2005)

Well, here's an update in this ongoing saga. I have learned that these barrel sleeves actually have a name. Blast tubes. I still haven't benn able to find out why they were employed or what the actual effect, if any, was as a result of their employment.

I believe they were constructed from stainless steel.


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## DAVIDICUS (Apr 24, 2005)

Here's a picture of some M2's recovered from a downed P-47. Note that it appears that the blast tubes are attached to the guns themselves.

From: http://www.pacificwrecks.com/aircraft/p-47/42-75940.html


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## Matt308 (Apr 24, 2005)

Now that is interesting and appears to blow my theory all to hell. Unless...

No, I'll withold my comments and appear the fool instead of voicing them and removing all doubt.

What in the hell could those be used for? Might they have something to do with a design allowing extra cooling via the venturi effect? Can't see how though. Must be stainless steel. That's obvious. Stainless steel tubing? That's also VERY expensive.

Stainless steel is very common in modern rifle bores to maximize barrel life. These "blast tubes" don't appear to be much larger than a standard .50 BMG barrel with perforated heat sheild. Just random neuron firing to perhaps promote discussion.


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## trackend (Apr 24, 2005)

Look at the sleeves Dave they appear to be attached to the gun breech mechanism and not the Barrel this would mean M2's recoil action would be inside the sleeve and in the pic of the P47's wing the sleeves appear to be mounted solidly to the leading edge of the wing with a stainless plate this to me points too some form of hot gas suppression within the wing/or a form of flash eliminator I shall keep looking however.


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## Matt308 (Apr 24, 2005)

Here's some more info. It appears that virtually every aircraft with fuselage/wing mounted machine guns and cannon made use of blast tubes. I found my most valuable information in a patent search of all the places!  

The blast tubes apparently serve multiple purposes depending upon the mounting locations and the problems that are being solved. Blast tubes are used for any or a combination of the following:

1) To act as a blast suppressor by protecting the aircraft structure from the overpressure of firing the weapon. The overpressure for .50 BMG and up is rather acute and structurally fatiguing.

2) To act as a blast diffuser to minimize dispersion of rounds fired by multiple high caliber weapons in close proximity to each other.

3) To act as a blast diffuser to minimize muzzle flash.

4) To act as a means of venting hot gases from the aircraft structure.

5) To act as a structural means to minimize barrel "whipping" and thus minimize dispersion of rounds from point of aim.

6) To simplify weapon installation, removal and maintenance by aircraft armourers.

7) To facilitate a solid structural support for the weapons to minimize firing inaccuracies of the mounted gun due to wobbling of its firing axis relative to the aircraft. (seems similar to 5 above)

Here are a couple of pics from a Hurricane that I also found. Note that blast tubes appear to used for solving a different set of concerns than those of the P-47, as the mounting appears quite different.


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## trackend (Apr 24, 2005)

Brilliant find there Matt I think thats solved Dave's query


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## DAVIDICUS (Apr 24, 2005)

No, I don't think it does.

Yeah, blast tubes are quite common. 

_1) To act as a blast suppressor by protecting the aircraft structure from the overpressure of firing the weapon. The overpressure for .50 BMG and up is rather acute and structurally fatiguing. _

Why then do we not find a similar design on all other U.S. aircraft with wing mounted .50's? We don't see blast tubes that extend beyond the leading edge of the wings on other "P" and "F" designated aircraft.

_2) To act as a blast diffuser to minimize dispersion of rounds fired by multiple high caliber weapons in close proximity to each other. _

Again, why then do we not see this feature employed with other aircraft?

_3) To act as a blast diffuser to minimize muzzle flash._

The .50 BMG isn't a cartridge known for problematic muzzle flash. Why then do we not see this feature employed with other aircraft?

_4) To act as a means of venting hot gases from the aircraft structure. _

Why then do we not find a similar design on all other U.S. aircraft with wing mounted .50's? We don't see blast tubes that extend beyond the leading edge of the wings.

_5) To act as a structural means to minimize barrel "whipping" and thus minimize dispersion of rounds from point of aim. _

*This is interesting. I find this valid. Barrels do indeed "whip" when fired.*

_6) To simplify weapon installation, removal and maintenance by aircraft armourers. _

Matt308, can you explain this concept to me? I don't see how removal and installation of the guns would be facillitated by the barrels being located within these stainless steel blast tubes. The receiver is still locked into place at the forward and rear.

_7) To facilitate a solid structural support for the weapons to minimize firing inaccuracies of the mounted gun due to wobbling of its firing axis relative to the aircraft. (seems similar to 5 above)_

Agreed. it does appear related to #5. 

It is possible that the P-47 was designed with these protruding blast tubes to solve problems that did not exist. Were the P-47's guns mounted far forward in the wing so that even in the absence of blast tubes, the barrels would protrude in a like manner? If so, why were they mounted so far forward that three of each battery of four protruded so far?

Were they merely a cosmetic addition designed to enhance the lethal appearance of the P-47?


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## Matt308 (Apr 24, 2005)

Aww c'mon David. Your busting my balls.  

I noted the 7 findings as a compendium of rationale for blast tubes. Not as the final justification of the choice for the P-47. As a lawyer, you should know that putting forth a defense is not formulated upon a single thrust in logical argument, but rather from a collective set of arguments that overwhelmingly influence the conclusion as being truthful based upon the preponderance of the evidence.

Same in reverse engineering. These 7 features of blast tubes are the result of different installations, their resultant problems, and identification of a single solution. Engineering consideratios such as metallurgy, kinematics, environmental, thermodynamics, structural, lifecycle support of the equipment, and human machine interface all drive unique solutions that may be combined in a composite approach to maximize common design goals.

The basis for blast tubes is no different. The P-47 offered unigue design challenges; of which the blast tubes afforded an ability to address a "composite" of P-47 engineering concerns. I doubt that you will ever discover a comprehensive list of the all the top down derived requirements that forced the blast tube incorporation decision in the P-47. Like legal discourse, sometimes decisions are driven by politics, fate, historical legacy, and even pure ignorance (ie the not invented here syndrome).

In my search to discover the above 7 advantages of blast tubes, I did discover that virtually all...read that ALL...fighters contained some form of blast tube installation as part of their weapons package. Check out B-25s, PBYs with forward firing guns located in the keel, F3Fs, P-38s, P-39s, P-40s, Boeing P-26 Peashooters, etc. Hell even the Polikarpov I-16 used them.

We can all make suppositions about which of the 7 fit the P-47 design criteria. The primary wing spar on the P-47 is located right behing the gun bay and 4 guns must be staggered to accomodate the perpendicular feeding belts from the magazines. This is the primary reason for the staggered design of the .50 BMGs and thus perhaps one (1) rationale for the exposed blast tubes. However, to come full circle, I will bet you bottom dollar that ease of maintenance ranks right at the top.

Take the word of a lowly aerospace engineer. My advice is free and is worth exactly what you pay for it.


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## DAVIDICUS (Apr 24, 2005)

I don't know why you think I'm busting your balls. And, "... putting forth a defense ..."? Let's leave our occupations out of this. After all, as a "lowly aerospace engineer" you should know that while many reasons may generally exist for a design feature on an aircraft, every aircraft will not necessarily benefit from said feature.  

Most of what we do on this forum is to apply our common sense, education and life experience to issues that are unclear or subject to competing claims. I think it works out pretty good.

As you pointed out, all aircraft appear to have employed blast tubes so it isn't the existence but the protrusion that is the issue. You mentioned something interesting when you said that the main wing spar is right behind the gun bays. This would explain the forward placement of the guns since they were staggered.

Do you know if the Corsair, Hellcat, Wildcat and Warhawk have staggered mountings as well? I believe that the Mustang did not have staggered mountings.

BTW - Is the 308 after your name .308 Winchester aka 7.62 x 51 NATO?


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## Matt308 (Apr 24, 2005)

I think that you will find that most all wing mounted guns are forward of the main wing spar. Thus, you will find most wing mounted guns are staggered to minimize mechanical complications associated with more than two guns mounted side-by-side. A main wing spar mounted mounted forward of the gun bay in a fighter aircraft is highly unlikely due to the fact that it would seriously complicate the ability carry normal wing loads associated with maneuvers.

Don't take my "ball busting" comment too seriously. I'm just asserting myself in a forum other than in my wife's presence where I feel vindicated when I'm done.  

Yes, Matt308 is taken from the same family of cartridges. I'm a fledgling, yet avid gun collector who needs another 5ft safe. I have carried my silly name across forums only to minimize my need to exercise the grey matter (which I find increasingly difficult as time and beer goes by)

No hard feelings?....

I'm off to read some Docter Seuss B Book to my youngest son who made a hat trick in soccer today. Talk with you later.


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## DAVIDICUS (Apr 25, 2005)

I understand that guns are mounted ahead of ther main wing spar. I am assuming that the main wing spar of the P-47 was much further forward in the wing than in a Corsair or Hellcat (which I am further assuming had staggered guns). Do you agree?

Such an advanced main spar placement would explain why the blast tubes had to protrude so far.

How old is your son? I have one whom just turned 18 months. This morning I took him to the Skyport Cafe at the San Carlos Airport (a little airport near where I work) for pancakes and to watch the Cessna'a take off and land.


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## trackend (Apr 25, 2005)

I cant believe they would interfere with an aircraft's armament for aesthetic reasons Dave, as they are called blast tubes I would have thought they are for blast IE hot gases. You have a point Dave regarding maintaining barrel alignment the M2's barrel being reciprocating would only be as accurate as the guides that the barrel moves on so supporting the barrel could be an answer but would not this increase the chances of a stoppage caused by the barrel seizing in the blast tube guides due to heat as to have any effect in maintaining the barrel alignment the tolerances would have to be fine. I believe the stagger is to off set the belt feeders within the wing.


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## DAVIDICUS (Apr 25, 2005)

"_I cant believe they would interfere with an aircraft's armament for aesthetic reasons Dave ..._"

I was being sort of tongue in cheek and suppose I should have put a  after that comment.

This whole issue, of course, is really about why they protrude so far. If the main spar was directly behind the number four gun and there wasn't that much room ahead of the spar, I could see how a staggered mounting would result in the number one, two and three guns protruding ahead of the leading edge of the wing.

What do you think?


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## Matt308 (Apr 25, 2005)

If I recall correctly the P-51 is not staggered. The P-40, F4U and F6F are.

My youngest son is 5. My older son is 10. Those are fun times at the airport. My grandfather used to take me to the Birmingham AL airport to watch the planes. This airport was shared with the Alabama Air National Guard and also had some sort of maintenance depot for C-135s. I remember seeing mostly F-4s and on occasions F-101 Voodoos (rare treat). I distinctly recall watching an airshow where the F-4s ligned up for a full throttle take-off and the poor crowd control resulted in hundreds of people literally running toward these huge planes roaring in full afterburner. Someone must have been on the ball, because they released brakes and got the hell out of there. I also recall that later in the show an F-101 buzzed the airfield perpendicular to the runway (and right over the crowd I might add). Scared the hell out of everyone with this 50ft pass from behind. Alas, those days are no more. This was about 1976, I think.


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## Matt308 (Apr 25, 2005)

It is interesting to take a look at the P-51 gun bay. You will note that the port bay innermost gun has a belt feed that takes a 30-40 turn forward to account for the non-staggered installation. I'll have to look, but this too may have been influenced by wing primary structure.

David, I'm still thinking that somehow the guns aligned parallel with the ground also plays into this somehow. I'm wondering if we are too focused upon a single rationale when in actuality the designers would be struggling with many design requirements that would have influenced their final choice. A common mounting block, coupled with wing spar location, belt feed complexity, maintenance, the need to maintain weapon accuracy, etc are all contributing to the Republic choice. I would bet that if you asked two different Republic engineers why the choice and depending upon their engineering discipline you would probably get two different answers.


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## trackend (May 19, 2005)

Old subject but I spoke too a guy at Duxford today who is a specialist fitter on the P47 he said the Blast tubes act as heat shields to protect the wing skins and the leading edge they are staggered for belt feed configuration.
generally all blast tubes do the same job.


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## DAVIDICUS (May 20, 2005)

Understood. The question really was why they protruded so far. If the P-47 had just six guns instead of eight (remove the inboard gun), it would appear that the outermost three guns still protrude much, much further than on the P-51, F-4, F-6, F4U, P-40, etc.


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## Gemhorse (May 20, 2005)

A real interesting topic...I've always wondered why the P-47's guns were aligned as such, and find Trackend's friend at Duxford assertion a very balanced answer....I'm not sure, but firstly, are the barrels longer than the norm?

The P-47 was unique in having 8x .50's, and they indeed added to it's 'lethal-look', they were a great gun platform and perhaps the best strafer of the war, but wouldn't the whole gun and blast tube be adjustable for sighting, as there would be great advantage in adjustment if say they were being used for ground-suppression duties for say a week, and then re-adjusted for a reassigned week of escort duties...the alignment for these two duties that they were used for, would be useful, indeed critical, to their successful implementation respectively...
Also, as they were very fast and able craft, the barrels being extended wouldn't have had any real adverse effect on the aerodynamics, so perhaps one could conclude they were assisted in cooling by the extra airflow...on the other extreme, did they have any internal anti-freeze system?

Please bear in mind I'm an Artist, not an Armourer, and comment ask all this out of genuine interest in this fine aircraft.......


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## DAVIDICUS (May 20, 2005)

Perhaps the main wing spar was so far forward that the guns, when placed in a staggered arrangement, had to be located much further forward in the wing in order to accomodate their placement ahead of the wing spar.


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## Gemhorse (May 20, 2005)

Yes, that's definately possible, they do have a healthy wing area.....I've always liked their 'ellipical-type' wing shape.....Perhaps someone has an exploded-plan drawing of the P-47, to study the guns placement abit more closer....


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## lesofprimus (May 20, 2005)

The wing of the P-47 is a full cantilever type employing 2 main spars and stressed skin and multicellular construction. It has a span of 41’, root chord of 109½", mean aerodynamic chord of 87.46"; a 5.61 aspect ratio; an angle of incidence of +1° and a top surface dihedral of 4° . Angle of incidence and amount of dihedral are fixed.

main spars which support attachment of the wing to the fuselage and three auxiliary spars, one each supporting the aileron and flap and the other supporting the landing gear.

Main spars are constructed of E-shaped cap strips riveted to webs of varying thickness from a minimum of .032" for the outboard web of both spars to a maximum of .250" thickness for the inboard web of the forward main spar. Both main spars are reinforced at suitable intervals by extruded angles which also serve as anchors for frame installations.

Inboard ends of the main spars of each wing are fitted with a pair of wing hinges which are pinned to the mating fuselage hinges by split bushings; tapered bolts expand these bushings to a tight fit, thus securing positive attachment.

The aft auxiliary spars support the movable surfaces and are constructed of angle cap strips and webs of .072" to .025" thickness. The landing gear auxiliary spar, since it is subjected to landing loads, is of somewhat heavier construction—namely, .091" web and is reinforced similar to the main spars.

Flanged ribs of alclad 24-ST are secured between spars at the angle stiffeners. Ribs vary from .051 to .032 with the exception of the root chord rib and gun bay partitioning ribs; the root chord rib is .064" and the gun bay partitioning ribs of .064".

Nose and trailing edge ribs are flanged and are also of Alclad 24-ST.


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## Nonskimmer (May 20, 2005)

Ah, excellent. Especially the middle pic of the exposed bays.


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## DAVIDICUS (May 20, 2005)

I wish we had similar illustrations of the internal structure of other aircraft's wings so that the locations of the main wing spar can be compared. 

The P-51 didn't have staggered mountings. Perhaps the other American fighters didn't either. That would be one explaination as to why placement of the guns ahead of the main wing spar would not necessitate such an extreme protrusion of three of the four barrels ahead of the leading edge.

Nice pictures. That's a nice model. It appears to correctly display the position of the guns as parallel to the ground. Most P-47 models feature the guns aligned with the leading edge of the wing.


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## Gemhorse (May 20, 2005)

Aw, really awesome!!...I thought they may have had more barrel length, but they're definately packed-in real tidy!...
Impressive compared to the P-51's, but is there a difference in barrel length?.....


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## DAVIDICUS (May 21, 2005)

Ah, yes. See how far the guns sit back in the wing of the P-51? They are mounted much further forward in the P-47. The structure of the P-51 wing would appear not to have a main spar configured like the P-47.


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## FLYBOYJ (May 21, 2005)

Excellent stuff Les! and a great description. Not that it matters but you even called out the right material and size and didn't call the sheet metal "gage material," as an aircraft maintainer, you bring tears to my eyes! "Someone else" said that once to me on this forum, hearing it was like scraping your fingernails on a blackboard!  I told "them" that gage sheet metal is used in air conditioning construction, not aircraft! 8)


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## DAVIDICUS (May 21, 2005)

If you think Les wrote that I have a box of magical rocks I'd like to sell you.  It was cut and pasted from the website below. 

http://rwebs.net/avhistory/history/p-47.htm


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## the lancaster kicks ass (May 21, 2005)

David said:


> If you think Les wrote that I have a box of magical rocks I'd like to sell you


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## trackend (May 21, 2005)

Great Info Les but unfortunately you lost me at root chord  . The P47 it appears directly to do with feeder configuration as looking at the pic the weapons could have been aligned in anyway as there seems to be plenty of room for the actions the P51 definately seems to be more constrained by space.


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## Nonskimmer (May 21, 2005)

So DAVI, these rocks...how many colours do they come in, and will they make me pretty?


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## lesofprimus (May 21, 2005)

Cut and paste...... But i did take the time to find it and do it, so ill take a partial credit, maybe 32%.......


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## trackend (May 21, 2005)

No Les more like 32.45% at least and a cycling proficiency badge as a reward


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## lesofprimus (May 21, 2005)

Actually, I found the same information, word for word, on 5 different sites........ It was rather frustrating actually....

And thx trackend, I shall definatly make use of the new badge...... On what I have no idea......


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## FLYBOYJ (May 21, 2005)

So tell me about those rocks......


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## DAVIDICUS (May 21, 2005)

_"So DAVI, these rocks...how many colours do they come in, and will they make me pretty?_"

Worked for me.


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## lesofprimus (May 21, 2005)

Probably the same rocks they used from the TV show Land of The Lost, with those mean ol nasty Sleestacks.........

"HHHIIIIIISSSSSSSSSSSSSSSSS"...........................


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## trackend (May 21, 2005)

You guys crack me up      your twice as barmy as I am and it,s taken me fifty odd years to reach this level (obviously superior US lunacy)


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## lesofprimus (May 21, 2005)

I love being Barmy, especially since i have no clue what it means....


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## cheddar cheese (May 21, 2005)

Barmy, ie crazy, mad, hyperactive, etc...


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## Nonskimmer (May 21, 2005)

lesofprimus said:


> I love being Barmy, especially since i have no clue what it means....


I didn't know it either. I'm afraid I only speak functional Brit. I'm not exactly fluent.


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## lesofprimus (May 21, 2005)

Having been to England 3 times, for about 8 days combined, i didnt pick up enough of the lingo to make it work... Some of it is pretty crazy, just like some of ours on this side o da pond is to them Brits...

I remember, back in the day, circa 1980 or so, when my Dad's buddy from England came over with his family for a summer visit... His son was about my age... 

He used the word "fag" for a cigarette and we all thought him out of his mind.......

Then again, some morons here in the Southern US call ALL sodas Cokes... Theyll say gimme a Coke when they want a Sprite or Dr. Pepper.... Makes no sense.... They just point out what they want and say, "Gimme a Coke..."

Freakin Rednecks.......


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## Nonskimmer (May 21, 2005)

Well, in my neck of the woods it's a strange combination of North American and British terms. Mostly from this side of the pond though.  
Some of the British ones I know, but others I don't.


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## lesofprimus (May 21, 2005)

> in my neck of the woods it's a strange combination of North American and British terms.


Thats gotta drive u guys insane....... It could probably get ugly if u start combining some of the words to make sentences.....


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## Nonskimmer (May 21, 2005)

"Hey fag, gotta fag?" 

WHAM!!!


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## lesofprimus (May 21, 2005)

That was totally gay........


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## Nonskimmer (May 21, 2005)

Hence the "WHAM!!!" at the end. Fag still means gay around here.


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## lesofprimus (May 21, 2005)

I know, I was following up ur funny with my own funny........


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## plan_D (May 21, 2005)

Two funnies in such a short time is too much for me.


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## DAVIDICUS (May 21, 2005)

All I get is this.


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## Nonskimmer (May 21, 2005)

Hmmm. 
Must be your settings.


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## trackend (May 22, 2005)

I always preferred snout or cough stick too fag (reminded me too much of the old upper class fag system in public schools)
As you may gather im a bit more working class sort of a navi with technical qualifications


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## evangilder (May 22, 2005)

Funny, I understand alot of the British slang still. I did live there for three years, but I left there almost 20 years ago. I guess some things never leave your memeory. Now if I could only remember where I left my keys...


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## lesofprimus (May 22, 2005)

THE LANC STOLE EM'..............

Why u think he aint been around lately..........


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## cheddar cheese (May 22, 2005)

Yeah, you wanna be careful of them theiving farmer types...


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## evangilder (May 22, 2005)

Aha! How'd he manage to get across the pond, break into my house and steal my keys in such a brief timeframe.  He must have been plotting this for some time... It's a key conspiracy, I tell ya!


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## Nonskimmer (May 22, 2005)

He's probably not in Cornwall at all. He's probably holed up next door to you.


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## cheddar cheese (May 22, 2005)

His next culprit was les, hence the strange substance on his lawn...that was actually lanc


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## Nonskimmer (May 22, 2005)




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## evangilder (May 22, 2005)

Hmm, Lanc poo?


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## cheddar cheese (May 22, 2005)

No, just lanc  lanc poo could wipe out an entire army at a range of 5000yds


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## lesofprimus (May 22, 2005)

> that was actually lanc


What, he suddenly is one of the morphing type of XMen or something??? Too bad i had to take Lanc and chuck him over the fence... If I had known earlier, i would scooped him up and invited him in for tea and crumpets, or in this case, coffee and a bagel.........

BTW, do u guys have Thomas's English Muffins over there in England??? The nooks and crannys are like the greatest thing known to the baking world next to Cornish Pastries.......


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## cheddar cheese (May 22, 2005)

I dont know, but im sure youve asked this before...To me a muffin is a muffin


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## evangilder (May 22, 2005)

Nope, Les. "English" muffins are an American thing, sort of. According to foodreference.com:
_
The story is that an English baker, a certain Samuel B. Thomas, started making these flat chewy things in America over 100 years ago, from his mother's tea cake recipe. The English deny that they ever heard or saw anything like it until they were imported from America. Today you can find Thomas' English Muffins in most English supermarkets. Imported from America.

The curious thing is that 'muffins' in the U.S. are not anything like these so-called 'English Muffins'. (Maybe this was an inexperienced English immigrant baker's attempt to make crumpets* from a half remembered recipe of his mother's.) Muffins in America are 'quick breads' that is, made with no yeast, but leavened with egg and baking powder.

‘English Muffins’ are about 3 inches round and 1 inch high, yeast raised (basically a bread dough) and baked on a griddle. To get the proper texture when split in two they should not be cut with a knife, but should be split with a fork. The resulting rough texture gives them a certain crunchiness when toasted (and helps them hold gobs of butter and preserves). _


For the Brits here, they look like this:
http://www1.wolfermans.com/eoneCommerce/Shop?Dsp=30000&PCR=1:1000&R=667


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## Nonskimmer (May 22, 2005)

And they're great toasted with peanut butter. Mmmmm, good!


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## lesofprimus (May 22, 2005)

> The resulting rough texture gives them a certain crunchiness when toasted (and helps them hold gobs of butter and preserves).


Hence the "nooks and crannys" comment...... I just ate one of em and I gotta tell ya, i love them freakin things........


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## evangilder (May 22, 2005)

Wow, how did we go from P-47 guns, to Lancs kleptomania and public defecation to English Muffins?


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## lesofprimus (May 22, 2005)

Im not sure but it definatly sets a record for different topics on 1 page......


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## trackend (May 22, 2005)

Ive never had a muffin in me life.
OK Evan I got all that info and as you are a mine of culinary knowledge (mixing food with slang) how did it end up that we call a female a piece of crumpet or a tart and what about the flaming onion ack ack rockets.
That's it, I managed to get food and fire power in one sentence were almost back on thread.


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## the lancaster kicks ass (May 22, 2005)

les said:


> Cornish Pastries



*shock*

that's really quite offensive, it's a cornish pasty, cornish pastries are in fact very rare, almost unheard of these days.............

and where i put you key, you'll be lucky if it comes out in the nest few weeks, i'll be lucky if it comes out at all


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## lesofprimus (May 22, 2005)

LOL........ Pastries are the plural form of pastry............

Ummmm Pasty???? With no R???? Was that a typo?


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## cheddar cheese (May 22, 2005)

No they are actually called Pasties...Why? I dont know, The Cornish are harder to understand than women


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## trackend (May 22, 2005)

http://www.cornwall-online.co.uk/history/pasty.htm
mind you this still dont give the reason for the name


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## Matt308 (May 24, 2005)

So to quote page one of this rather diverse thread...

"The primary wing spar on the P-47 is located right behing the gun bay and 4 guns must be staggered to accomodate the perpendicular feeding belts from the magazines. This is the primary reason for the staggered design of the .50 BMGs and thus perhaps one (1) rationale for the exposed blast tubes. However, to come full circle, I will bet you bottom dollar that ease of maintenance ranks right at the top."

I knew you guys would come around.


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## Monkeysee1 (Aug 11, 2005)

Matt 308, you said that the P47 was designed for ground strafing? WHAT?!? No man, it was designed as a high altitude fighter first and foremost. Its superiority as a ground attack aircraft was incidental. 

All US aircraft have blast tubes mounted for their .50's. The P47's are staggered to allow more ammunition to be carried and allow separate feeding of the guns so they don't interfere with each other. Other US aircraft don't have this staggered design necessarily because this was a side benefit of the elliptical wing the P47 used... and let's face it... it was a big enough wing to allow this. 

Pretty sure on this one but if I'm wrong, let me know.


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## the lancaster kicks ass (Aug 18, 2005)

i can't believe you don't know what a pasty is les!


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## cheddar cheese (Aug 22, 2005)

I had an Italian pasty in Spain. Its like a pasty but with ham, cheese, and tomato. And its a piza base instead of pastry, but still.


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## lesofprimus (Aug 22, 2005)

Pasty is what u call the little geeky pale kid who looks like he was inside a nuclear reactor for 2 months........

"Damn Tommy, your skin looks so pasty dude..."

However.........

"Man, Ill tell you, that pastry that Lanc gave me was awesome... Had cheese and ham and little Rosemary in it...."


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## cheddar cheese (Aug 22, 2005)

Well the Cornish are odd.


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## chuter (Apr 21, 2013)

Wow, stumbled across this old thread and saw no real answer for the OP (I hope he hasn't already passed on ...lol). Technically, what the P-47 has on its barrels aren't blast tubes. Blast tubes are located ahead of a gun muzzle, when the muzzle is still inside the aircraft, to protect the structure (the Mustang uses a short one on the inboard, staggered gun). What the P-47 uses are actually a non-perforated cooling jacket or sleeve. The reason is because the barrels protrude from the leading edge of the wing which usually causes serious problems with the airflow, particularly at high angles of attack, because the standard or ventilated jackets cause a lot more turbulence. This becomes a much bigger issue with laminar airflow wings. The ideal goal is to have the guns housed entirely within the wing or, if not possible, have the protruding barrel act as little like a vortex generator as possible by making it more aerodynamic with a non-perforated jacket or a fairing. Take the laminar winged Hawker Tempest as an example: early production had protruding, faired barrels while the later production had the flush Mk V short barrel cannon. There were multiple reasons for going to the Mk V but the Mk V itself was developed as an aircraft cannon with a short barrel for aerodynamic as well as other reasons. 

And now, maybe, the topic can fade back into obscurity with dignity ... lol.


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## Njaco (Apr 21, 2013)

[email protected] ! Where did all this dust come from? 

Thanks chuter! Great info.


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## syscom3 (Apr 21, 2013)

Wow. Heck of a post from a new member. Well done!


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## glennasher (Apr 21, 2013)

I thought maybe it was to stagger the MG receiver placement in the wings, to make more room for the ammo belts to travel from magazine to MG. M2 receivers are quite long, and staggering them in relationship to each other would seem to allow more room for the feeding mechanism. But that's just another guess.


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## tomo pauk (Apr 21, 2013)

+1 on that.


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## Elmas (Apr 22, 2013)

These sleeves seem to be present in the italian Serie 5 fighters.....


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