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XyZspineZyX
09-15-2003, 05:37 AM
I know a lot of you jug pilots out there complain about the 1 shot engine kill - you take a light MG hit and bam, you got oil on the windshield and smoke coming out of the left waste gate. Well I think I have a explanation...

The oil coolers are just in the chin of the engine, right in the cavity there. You take a hit to the chin, and your engine is out of the action, period.

I was looking at a detail drawing of a P-47D-10, and noticed that the oil coolers were really exposed there. They sit on the rear edge of the engine, just on the bottom of the cowling.

Anyways, I'll post the cutaway if anyone would like to see it.

http://www.mechmodels.com/images/klv_ubisig1a.jpg

XyZspineZyX
09-15-2003, 05:37 AM
I know a lot of you jug pilots out there complain about the 1 shot engine kill - you take a light MG hit and bam, you got oil on the windshield and smoke coming out of the left waste gate. Well I think I have a explanation...

The oil coolers are just in the chin of the engine, right in the cavity there. You take a hit to the chin, and your engine is out of the action, period.

I was looking at a detail drawing of a P-47D-10, and noticed that the oil coolers were really exposed there. They sit on the rear edge of the engine, just on the bottom of the cowling.

Anyways, I'll post the cutaway if anyone would like to see it.

http://www.mechmodels.com/images/klv_ubisig1a.jpg

XyZspineZyX
09-15-2003, 05:44 AM
Something else that I recall but haven't seen mentioned;

Does the radial engine in the P-47 have a "master" cylinder? I just recall in the past reading that you could knock away a certain number of the cylinders but killing the master cylinder would render the engine inoperable.

I'm wholly uninformed when it comes to this type of aero-engine. Anyone who can confirm or squash this recollection, go for it.

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XyZspineZyX
09-15-2003, 05:47 AM
I'm afraid thats beyond me as well. Definately worth looking into!

http://www.mechmodels.com/images/klv_ubisig1a.jpg

XyZspineZyX
09-15-2003, 07:10 AM
If it was so vulnerable, why didn't it get swatted out of the sky with impunity in the real world? It was one of the most combat survivable planes of the war! In reality, it's extremely difficult to hit the nose of an aircraft going 200+ miles per hour, and even harder to hit the crankcase or the oil cooler which were much smaller than the whole cowling and were protected by rows of cylinders from most angles.

In FB, and to a lesser extent in Il-2, the gunners and AI are ludicrously accurate, even when the aircraft they're in and the one they're shooting at are rolling and skidding all over the sky; certainly, the lateral G-forces would pretty much preclude anything like marksmanship in those cases, but noooo, they're freakin' Davy Crockett in all attitudes and maneauvers. Or, the damage model is loaded against the Jug.

The explanation of the vulnerability is simple and has no basis in anything except human prejudice.

"Here's your new Mustangs, boys. You can learn to fly'em on the way to the target. Cheers!" - LCOL Don Blakeslee, CO, 4th FG, March, 1944

XyZspineZyX
09-15-2003, 07:27 AM
hobnail wrote.....Does the radial engine in the P-47 have a "master" cylinder? I just recall in the past reading that you could knock away a certain number of the cylinders but killing the master cylinder would render the engine inoperable........................................ .. TENMMIKE ......no but there is a master rod that the articulated rods( all the other ones of that radial bank) are conected to ( just like all the other radials).it is much larger than the other rods disabilingthat rod will have the same disastrious effect as the others although it could tear up a little more...its not comman for a engine to suffer that kind of damage and stay together although there are ways that it can its just rare .....please see addional info on this post under my name further down

U.S. infantry 84-91

Message Edited on 09/14/03 11:47PM by tenmmike

Message Edited on 09/15/0301:53PM by tenmmike

XyZspineZyX
09-15-2003, 07:28 AM
The Thunderbolt was definitely very tough indeed.
If you want to read a great account of the jug in action read "Thunderbolt" by Robert Johnson. After reading about his experience in combat with the P-47 you will be amazed at how much punishment it could absorb and still fly. He even talks about an entire cylinder being shot away and the engine still running. The radial engines were generally more durable than liquid cooled ones. The engine was the biggest reason the P47 was well suited to the ground attack role, even though it performed better as a fighter at higher altitudes.

XyZspineZyX
09-15-2003, 07:37 AM
^

Message Edited on 09/14/0311:43PM by tenmmike

XyZspineZyX
09-15-2003, 07:45 AM
Harry Voyager has done a great deal of research into the 1 hit phenomenon (which still exists) and has posted quite a bit of information, including stills and tracks as to how it occurs.

The basic issue is that a round will enter the SC intake and destroy the blower, which leads to total engine failure.

In real life, the chances of this actually happening the way it is modelled in the sim are probabaly thousands to one AGAINST.

Inspite of all the information that has been posted by Harry, et al, Oleg has thus far failed to acknowledge that a problem even exists, let alone address it.

S!

http://members.cox.net/miataman1/WAR-08.jpg

XyZspineZyX
09-15-2003, 01:45 PM
chris455 wrote:
- Harry Voyager has done a great deal of research into
- the 1 hit phenomenon (which still exists) and has
- posted quite a bit of information, including stills
- and tracks as to how it occurs.
-
- The basic issue is that a round will enter the SC
- intake and destroy the blower, which leads to total
- engine failure.
-
- In real life, the chances of this actually happening
- the way it is modelled in the sim are probabaly
- thousands to one AGAINST.
-
- Inspite of all the information that has been posted
- by Harry, et al, Oleg has thus far failed to
- acknowledge that a problem even exists, let alone
- address it.
-
- S!
-
Put the tuffness back and finish fixing the the roll. Plz!

http://www.imagestation.com/picture/sraid79/p9141f290fa1c1c59a2dc382c77af21f3/fb1a8321.jpg


Lead Whiner for the P-47-30 and Hvars

Message Edited on 09/15/0312:51PM by Sniper762x51

XyZspineZyX
09-15-2003, 01:53 PM
The main question is.. happens this aigains LW or VVS planes... the fast rate of fire of the russian MG make such hits easier.. reminds me to the big head phaenomen in il2... If you flow a 109 are got PK very oftn.. REAL OFTEN...

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I./Gruppe

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XyZspineZyX
09-15-2003, 02:01 PM
I`m sorry, but I CANNOT believe any engine is invulnerable to a one -hit kill/damage. I`ve read all the talk about the engine and its properties and I am simply not convinced.

Nothing is that invulnerable and it certainly doesn`t explain why the aircraft wasn`t shot out of the sky in numerous numbers in WWII. The reason it wasn`t shot out of the sky was because it had good pilots flying them. Not invulnerable engines!

Man. I guess the P47 chaps won`t be happy till there`s a block of heavy concrete sat in place of that engine. Give it up already!



"Tis better to work towards an Impossible Good, rather than a Possible Evil."

SeaFireLIV.
(Spitfire & Escape Whiner Member).

XyZspineZyX
09-15-2003, 02:10 PM
Looks like more biased to me.

"Black nights"

"With all are might"

XyZspineZyX
09-15-2003, 02:12 PM
The engine cuts out way too quick.

XyZspineZyX
09-15-2003, 02:47 PM
Silent_414th wrote:
- Looks like more biased to me.

Not really bias, the LA's suffer the same fate, one hit in the engine section and it's toast.

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XyZspineZyX
09-15-2003, 06:14 PM
Cappadocian_317 wrote:
-
- Silent_414th wrote:
-- Looks like more biased to me.
-
- Not really bias, the LA's suffer the same fate, one
- hit in the engine section and it's toast.


true, you have a point. La7'a are also bad for that in FB

XyZspineZyX
09-15-2003, 08:18 PM
WEll Jugwhiners are right.. take a look at Lagg3 engine. You can't kill it..

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XyZspineZyX
09-15-2003, 08:27 PM
horseback wrote:
If it was so vulnerable, why didn't it get swatted out of the sky with impunity in the real world? It was one of the most combat survivable planes of the war! In reality, it's extremely difficult to hit the nose of an aircraft going 200+ miles per hour, and even harder to hit the crankcase or the oil cooler which were much smaller than the whole cowling and were protected by rows of cylinders from most angles.

In FB, and to a lesser extent in Il-2, the gunners and AI are ludicrously accurate, even when the aircraft they're in and the one they're shooting at are rolling and skidding all over the sky; certainly, the lateral G-forces would pretty much preclude anything like marksmanship in those cases, but noooo, they're freakin' Davy Crockett in all attitudes and maneauvers. Or, the damage model is loaded against the Jug.

The explanation of the vulnerability is simple and has no basis in anything except human prejudice.

You fail to see my point. I've been hit by the quad cannons from a Fw-190A8 from right on top of the engine cowling and gotten minimal damage to the engine! I've been hit in the rear with mk108 rounds, right in the supercharger, with zero damage! But when I take rounds to the chin of the cowl, the oil starts leaking! IT IS A TOUGH AND SURVIVABLE PLANE. I'm just saying that the OIL COOLERS can be damaged easily IF HIT FROM THE UNDERSIDE OR IN THE CHIN.

You're wanting the aircraft to take hits in the oil coolers and continue fighting, right? It doesn't work that way. When the oil coolers get damaged, it's time to high tail it home. You'll get about 5 to 10 minutes of combat power out of the engine before it dies, probably more if you go easy on the engine.

I'm including a picture in this post, which shows both the oil coolers position and the oil tanks position, both of which would be easily damaged if shot from the top, bottom or chin. This scan is from the book "Complete book of Fighters" by William Green and Gordon Swanborough.

http://www.mechmodels.com/images/p47cutaway1.jpg


Note that the oil tank is right behind the engine, and the red outline is the oil cooler. If you hit the oil cooler with anything from a rifle round to a cannon round, it WILL leak oil. Once you run out of oil, guess what? Engine gets hot. Looses lubrication. And eventually siezes up. The same holds true for just about every engine in FB, except for the Yak series. Fw-190s, when hit in the bumps on the sides of the cowl, will loose engine power as well; hits on the left side are almost instantly lethal. Hit the oil cooler on the underside of the 109 and it starts leaking like crazy. Get the picture?

Condsidering the weaponry the 1943-1945 Luftwaffle planes have, the survivability of the P-47 is staggering. Theres nothing better for SEAD or general ground attack than the P-47. In air combat, especially when its flight vs. flight, the P-47 more than holds its own.

For those curious, the above cutaway is of a P-47D-10.

Silent_414th wrote:
Looks like more biased to me.

Yeah but you fly the iron dog, so there! /i/smilies/16x16_smiley-tongue.gif

Go into the QMB sometime and try this: One P-47 with extra ammo against a Fw-190A8 with default armanent. If you take the P-47, keep note of where you get hit at. Arcade mode on is best for this; if you have the smoke trail coming out of the waste gate, look for a arrow anywhere in the chin. If you take the Fw-190, try to shoot the chin of the engine. Fact of the matter is, shoot anywhere near the waste gates and you'll likely put a hole in one of the oil coolers.

http://www.mechmodels.com/images/klv_ubisig1a.jpg

XyZspineZyX
09-15-2003, 08:33 PM
Hey Koro - How can that be a D-10 if it has the Pylons?

XyZspineZyX
09-15-2003, 08:39 PM
Some batches of P-47D-10s were equipped with wing shackles. I believe it was the later production run that was equipped with them.

Also, doesn't have the paddle blade prop of the later D-22 and on.

http://www.mechmodels.com/images/klv_ubisig1a.jpg

XyZspineZyX
09-15-2003, 08:41 PM
Vipez- wrote:
- WEll Jugwhiners are right.. take a look at Lagg3
- engine. You can't kill it..

The Lagg3 engine can be killed, but it takes a lot of punishment before it does stop working.

Maybe they put the Jug engine in the Lagg by mistake. /i/smilies/16x16_smiley-wink.gif

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XyZspineZyX
09-15-2003, 09:03 PM
Korolov,
I must admit this IS compelling evidence.

I would like more info before I follow Seafire's advice and "give it up"
Can you help us determine:
1. Did the P-47 have an armored ring in it cowl opening? Ala Fw-190F8 "Panzerring"?

2. Are the oil coolers in LINE OF SIGHT from the front, or do they "hide" behind the cowl opening?

3. Do other radial engined planes in FB suffer from a similar situation?

I have NEVER read of the Jugs vulnerability to fire from the front; on the contrary a vulnerable oil cooler was a sure fire way for a WWII plane to get a reputation for not being able "to take a hit". (MUSTANG?)
Although you argument is very worthy of exploration, I would like some answers to these questions. I think we may be on the road to understanding more about the problem due to your discovery-
S!



http://members.cox.net/miataman1/WAR-08.jpg

XyZspineZyX
09-15-2003, 09:14 PM
id say the il2 was a better ground attack aircraft /i/smilies/16x16_smiley-happy.gif

XyZspineZyX
09-15-2003, 09:31 PM
chris455 wrote:
- Korolov,
- I must admit this IS compelling evidence.
-
- I would like more info before I follow Seafire's
- advice and "give it up"
- Can you help us determine:
- 1. Did the P-47 have an armored ring in it cowl
- opening? Ala Fw-190F8 "Panzerring"?
-
- 2. Are the oil coolers in LINE OF SIGHT from the
- front, or do they "hide" behind the cowl opening?
-
- 3. Do other radial engined planes in FB suffer from
- a similar situation?
-

1. I'm afraid this is beyond me. There aren't any museums nearby that have a P-47 on display, but by judging the drawings I have its a moderately exposed intake. I imagine with enough shot quantity, a round would find its way into oil coolers. There is no obvious armor in front of them, around the intakes, but there is some light to heavy armor below them, to the sides, and rear.

2. From a direct forward view, there would be a line of sight to the oil coolers. It'd be hard to visually see them however, as they sit on the rear edge of the engine, and the supercharger intercooler air intake is between them.

3. Yes, the La series of planes suffer from this vulnerability to a great degree, and to a lesser extent, the Fw-190. The I-16 and I-153 engines don't leak oil, but rather catch fire when heavy damage is taken.

- I have NEVER read of the Jugs vulnerability to fire
- from the front; on the contrary a vulnerable oil
- cooler was a sure fire way for a WWII plane to get a
- reputation for not being able "to take a hit".

Mostly because AFAIK they weren't shot on the front a whole lot. If most of them did BnZ and ground attack, I'd imagine the shots that came near the intercooler would probably miss it by a fair margin.

The thing I don't understand is why the oil splashes up onto the windshield. If it is a intercooler hit, then it seems like the oil would leak down there, not rupture the oil tank.

- Although you argument is very worthy of exploration,
- I would like some answers to these questions. I
- think we may be on the road to understanding more
- about the problem due to your discovery-

I don't really hold it as full truth, just as one possible explanation to why the damn engine goes out so often.

http://www.mechmodels.com/images/klv_ubisig1a.jpg

XyZspineZyX
09-15-2003, 09:51 PM
hobnail i want to add a bit to what i posted last night in regards to the master rod.... and expand just a bit if the master rod fails at the (big) end (thats the end attathed to the crank shaft) than most certainly the whole engine will fail instantly as all the other rods of that bank(row) of cylinders will than also fail as they are attached to it...if it is a two row engine the un harmed row will then procede to destroy itself as well, do to the crank shaft throwing things around unbalanced etc in the damaged bank and there by causing the main housing ( case,block whatever term you want) to break up...............there i feel better , i could hardly sleep leaving this extra info out /i/smilies/16x16_smiley-happy.gif

U.S. infantry 84-91

XyZspineZyX
09-15-2003, 10:00 PM
Not that this really proves anything either way, but over the weekend I was playing online, and when an He-111 showed up I decided to jump into a P47-D, loaded extra ammo and went after it.

After the initial head on pass against the bomber, I dropped in behind and started closing slowly on it. Once I got within about .30 I throttled back and basically took up station right at the 6 o'clock position of the bomber and stayed there at a range of about .20 - .25.

Tactically it was a fairly stupid thing to do, but all I cared about at that point was inflicting max damage on the bomber as quickly as possible, and if it cost me an aircraft it didn't really matter.

I emptied everything I had into the 111, ran all 8 guns dry. Needless to say there wasn't a whole lot of the 111 left when I was done. No wings came off, but it was well and truly shredded, pilot killed, aircraft smoking badly and one dead engine.

During this time, the gunners on the bomber continued to fire at me, and hit me. I took all the hits in the front, and I knew I was getting shot, but I hung in there until I'd fired all of my ammo into the 111.

After I ran out of ammo I rolled over and dove away and then did a damage assessment.

There was none. At least none that I could see. No significant holes in the aircraft, no smoke from the engine, no adverse handling qualities or leaking fuel. Nothing.

Honestly, I was a bit surprised, considering that I'd just spent the last 30+ seconds being a lead sponge. I was expecting some kind of engine damage considering the number of hits it'd taken.

Next to the IL-2, the P47 is the toughest aircraft I've flown in the sim. In almost any other aircraft I'd have either been shot down or damaged to the point of having to break off if I'd tried that. If I'd been in a 109, the engine would have blown the instant the gunner pointed his gun at me, to say nothing of him actually firing. /i/smilies/16x16_smiley-wink.gif

I guess my point is that I haven't really experienced a problem with P47 engine durability. I don't fly it all the time, but when I do, I can't really think of many times where the engine gets damaged, at least not more often than any other plane.

On the other hand, I can't seem to jump into a 109 without sucking up engine hits every single time. I can't really remember a time where I haven't come away with engine damage in a 109.

XyZspineZyX
09-15-2003, 10:26 PM
if you approach from the six oclock low, you can avoid getting kicked in the teeth. I find the best attack though is from at least 45 to 90 degrees, when you let loose just about every round will hit. Amazing when they do.

http://www.mechmodels.com/images/klv_ubisig1a.jpg

XyZspineZyX
09-16-2003, 12:31 AM
Here is some additional information from http://rwebs.net/avhistory/history/p-47.htm

"In the creation and conception of the Thunderbolt, her designer exploited every known advantage and adopted first, the efficient single-engine, single-fuselage with its least interrupted wing span, concentrated weight and reduced frontal area; secondly, the Kartveli-designed airfoil section (Republic S-3) representing a culmination of the knowledge gained by years of high speed airplane design; and lastly, its supercharging system, which occupies a considerable volume of the fuselage structure, designed to supply 52" Hg of manifold pressure up to stratosphere levels for its 2800 cu in engine."

Good stuff!!!!

"The 2000 hp, 18-cylinder, air-cooled engine presented a great majority of the problems and one of the first was created by the demand for the perfect supercharging duct system, one that would offer the most efficient, least interrupted air flow; this requirement was neatly solved by an "unorthodox procedure"; that is, the duct system was designed first and then around it, the fuselage. The return of many P-47s to "home base" with gaping wounds in the fuselage is sufficient evidence that structural efficiency was not sacrificed by this procedure.

Since the conventional three-bladed propeller was not adaptable for the Thunderbolt installation, the four-bladed propeller was installed; the P-47, incidently, served as the first test stand for this propeller.

Although the four-bladed propeller was an admirable solution to the power gearing of the engine, there remained the problem of landing gear height. If minimum ground clearance for the 12 ft diameter propeller had been maintained by the conventional landing gear, its suspension would have been too far outboard and would have necessitated either less ammunition or guns; if the same firing power were to be maintained, the installation of the armament would have created an inefficient cumbersome wing structure; hence, the first telescopic landing gear. Republic designed, the landing gear is 9" shorter when retracted and therefore allows correspondingly farther inboard suspension. In this manner, both heavy armament installation and efficient wing structure are retained.

The installation of suitable fuel quantities was another of the major problems resulting from the adoption of the single fuselage and efficient turbo duct design and without detailing the development of the expansion of the internal fuel load of the P-47, it may be said, at present, that the latest Thunderbolt, details of which are not yet released, will have the greatest combat range of any pursuit airplane.

The need for ingenuity did not end with the solution to these problems, however, for the Thunderbolt's speed and natural habitat (above 30,000 ft) presented additional challenges. Ailerons "snatched and froze"; canopies could not be opened and control loads became excessive. These and other high-speed effects, which have now lost some of their mystery, were experienced during th P-47's early high speed runs and as solutions, Republic equipped the Thunderbolt with blunt-nosed ailerons, jettisonable canopies, all-metal control surfaces and was the first airplane to reduce rudder pedal loads by use of balanced trim tabs.

Fuselage

The fuselage of the P-47 is of semi-monococque, all-metal, stressed-skin construction, composed of transverse bulkheads and longitudinal stringers. The main or forward structure is divided into top and lower halves to station 302, while the tail "cone" or fuselage aft section, comprising the fuselage aft of station 302, is constructed as a unit. The upper and lower main fuselage halves are bolted at reinforcing angles built into the parting surfaces of the structure and joggled extensions on the upper half frames are spliced by riveting to the lower half frames. Assembly of the fuselage is complete by joining the aft fuselage section to the main section at the 302 station. Here, the facing frames of the forward and aft sections are riveted and bolted while the skin extension of the aft section is butt jointed to the main section skin and riveted to the last frame of the forward section.


Structural details of lower half fuselage structure

Structural details of upper half fuselage structure

Tail cone structure of the P-47 is shown here

Major structural units of the fuselage, two wing supporting bulkheads, are contained in the main lower half section. Each of the two bulkheads is constructed around a pair of 3" wide E section steel beams which extend the width of the bulkheads and serve as cross-ties. The wing support hinges, which are forgings of X4340 steel, extend into each end of the cross-tie beams and are secured to the ties by 3/8" bolts.

Forward or firewall bulkhead is faced with stainless steel sheet over alclad 24-ST 'sheet of .091 gauge and the aft side is faced with similar flat sheet, reinforced by corrugated sheet and channel section, all of alclad 24-ST.

The aft bulkhead incorporates the aft wing hinges. Except for the absence of stainless steel sheet facing and corrugated sheet, the structure is similar to that of the forward bulkhead.

Lower outboard ends of both the wing hinge bulkheads support trapezoidal shaped forgings; longeron components are riveted to these forgings, thus establishing the foundation for the remainder of the lower half fuselage structure. This lower longeron extends the entire length of the forward fuselage section and provides support for the remaining transverse structural elements. Stringers are located at suitable intervals from the longeron to the angle-reinforced parting surface of the lower half structure. Lower half frame segments are riveted to longeron and stringers and then flush riveted skin of various gauges with additional reinforcing sheets at the wing hinge fitting openings and other high stressed areas complete the structure of the main lower half fuselage section.


Upper and lower fuselage sections are assembled into a unit representing the forward fuselage section

The upper half forward fuselage section, though not as rugged as the lower half fuselage section, is constructed similar to the lower half section. The upper half forward bulkhead has, due to the absence of the 3" steel channel, less depth than the matching lower half and consequently is stepped back so as to present a flush surface on the aft face of the firewall. A corrugated sheet faced on either side extends to the upper engine mount cross-tie which is an angle of 24-ST. Since the structure above the engine mount cross-tie is the low stress area of the bulkhead, it is of single sheet thickness. Similar trapezoidal shaped forgings as employed in the bulkheads of the lower half section are bolted to the engine mount cross tie, to serve as the structural basis for the upper longeron.

The upper fuselage half extension of the aft wing-hinge-support-bulkhead consists of .064" flanged segments, extending to the upper longeron, spliced with .064" splice plates to both faces of the bulkhead.

Frame 180, representing the aft partition of the cockpit, unlike the wing hinge support bulkheads where the conditions are reversed, has rugged structure in the upper half section and flanged frame segment support in the lower half section. The additional ruggedness is due to the fact that this frame supports the aft armor plating.

The remaining upper-half frames aft of 180 are flanged semicircular segments tied by stringers.

The aft fuselage section, since it is constructed as a unit, employs complete frames and is tied by stringers in a fashion similar to the forward half structure. The tail wheel supporting frame is subjected to heavy landing loads and is therefore, considerably reinforced by vertical and horizontal extrusions and webs. This frame is also braced at the bottom by a box-like structure extending to frame 302. A transverse web is riveted along the upper area of the last three frames of the aft section, forming the support structure for the empennage.


Empennage is assembled to the fuselage just prior to the final assembly phase of the "Thunderbolt"

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 109", 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.

Fuselage Dimensions
Width (maximum) 53 "
Height (maximum without radio mast) 88"
Length (without engine mount) 398"
Length (with engine mount) 438 7/16"

Wing Construction

Wing covering is butt fitted, flush riveted, stressed skin type and is reinforced by extruded angle stringers. The cut-out skin area which includes inspection, access and maintenance doors, as well as the larger cut-out areas of the landing gear wells and gun and ammunition bays is about 16% of the total main panel area; the high percentage is indicative of. the rigidity inherent in the prime structure of the wing.

WINGS
Total area (including ailerons & flaps) 300 sq ft
Root chord 110"
Incidence +1?
Dihedral (top surface) 4?
Sweepback (L.E.) 3?
Aspect ratio 5.61
Mean aerodynamic chord length 87.46"
Span 41'


Wing of the P-47, whose airfoil section was developed by A. Kartveli and designated as Republic S-3., is a full cantilever type employing 2 main spars, stressed skin and multi-cellular construction.

Main members of the wing are the two 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.

Aileron

Ailerons of the P-47, representing about 11.4% of the total projected wing area, are Frise type, aerodynamically and dynamically balanced and are 16 in-lb overbalanced. They are hinged to steel forgings attached to the outboard auxiliary wing spar and are controlled by a system of push-pull rods; an all metal controllable trim tab is provided in the left aileron.


Ailerons on the P-47, representing about 11.4% of the total projected wing area, are Firse type, aerodynamically and dynamically balanced.

Flanged nose and tail ribs of 24-ST, are attached in staggered fashion to a main spar and alclad 24-ST sheet is flush riveted to spar and ribs.

Forged aluminum alloy hinges of the aileron are attached to the outboard auxiliary wing spar.

Landing Flaps

Landing flaps of the P-47, representing 13% of the total projected wing area, are NACA slotted trailing edge type. They are hydraulically operated, receiving pressure and fluid from the hydraulic system and during extension move first aft and then down and during retraction move first up and then forward; this movement, actuated by three trapezoidal linkage hinges, insures perfect positioning of the flap against the main panel, thereby maintaining the proper airfoil section. The linkage hinges are synchronized by attachment to a torque tube and the assembly is attached to the inboard auxiliary wing spar. Independent units are synchronized by hydraulic pressure. Flaps are pinned to the flap linkage assembly hinges with standard bolts.


Landing Flaps on the "Thunderbolt," representing 13% of the total projected wing area, are NACA slotted trailing edge type and are hydraulically operated.

The double cambered external surface of the flap is alclad 24-ST riveted to flanged nose and tail ribs which attach to a spar of 24-ST in symmetrical order; additional lightened reinforcing nose ribs are provided between each pair of the flanged nose ribs.

Compressible Recovery Flaps

Late P-47 models have incorporated flaps for the purpose of aiding in recovery from dives of compressibility speeds. These surfaces are operated by two electric, reversible, intermittent motors synchronized by flexible shafting. Magnetic brake and clutch assemblies are incorporated to prevent overtravel and switches limit the flap extension to 22? so as to hold "gs" to a safe value during "pull-outs."

The compressible recovery flaps are .188" flat sheets of 24-ST and are hinged at the landing gear auxiliary spar, located just forward of the landing flaps. In the retracted position, they are flush with the lower wing surface contour.

Empennage

The empennage of Thunderbolt is a full cantilever structure with a total projected area of 81.45 sq. ft.



All surfaces are metal covered and the elevators and rudder are equipped with controllable trim tabs of all metal construction.

Fin and the horizontal stabilizer assembly of the P-47 are of similar construction, both assemblies employing flanged ribs between a forward and aft spar and flanged nose ribs with 24-ST alclad skin.

Hinges for the tail surfaces and chain-actuated worm and screw units for trim tab operation are attached to the aft spars of both assemblies.


Construction details of horizontal stabilizer

Fin spars straddle the horizontal stabilizer assembly spars and at this junction are bolted to common splice plates thus forming a complete stabilizer unit. To install the complete stabilizer unit to the fuselage, the stabilizer forward spar is bolted to fittings on the horizontal web of the aft fuselage section and the aft spar is bolted to a plate fastened to the last frame of the fuselage.

CONTROL SURFACES
Settings & ranges of movement (?)
Ailerons
"Up" (from neutral) 16
"Down" (from neutral) 12
Elevators
"Up" (from stabilizer streamline) 30
"Down" (from stabilizer streamline) 20
Rudder
Right (from fin streamline) 28
Left (from fin streamline) 28

Rudder

The rudder is Handley-Page type having static and dynamic balance. Dynamic balance coefficient is less than zero and static balance is 25 in-lb under balance. The rudder trim tab provided dynamic balance as well as selective trim.


Details of P-47 fin structure (left) and rudder structure (right)

As all other surfaces of the P-47, this control surfaces is alclad aluminum alloy covered and employs a main spar and flanged ribs of 24-ST alloy.

Elevators

Elevators are of Handley-Page type with a dynamic balance coefficient of zero or less and static balance of 10 in-lb underbalanced. The elevators of the Thunderbolt are manufactured singly and are assembled into a unit by splicing torque tubes extending from the inboard nose sections of the elevators.


Elevators are of Handley-Page type having static and dynamic balance

The entire surfaces of the elevators are 24-ST alloy covered and constructed of a spar and stamped, flanged ribs; the torque tubes are secured to the first three inboard nose ribs of each elevator.

Elevators are hinged to the rear stabilizer spar and a torque-tube-pivot is provided by roller bearings staked in hinge brackets which are attached to the rear fuselage frame. The last control rod is linked to the elevator at a bracket that is part of the torque tube splice sleeve.

Power Plant

The power plant of the P-47 is a Pratt & Whitney R-2800, air-cooled, radial, twin row, 2000 hp engine. It is 72" long, 52 " in diameter and weighs more than a ton. It has a bore of 5.75", stroke of 6.00" and a displacement of 2804 cu in; the compression ratio is 6.7:1 and propeller drive ratio .500:1.

Engine is attached by Lord mounts and drives either electric or hydraulic controlled constant-speed 4-bladed propeller assemblies.

The NACA type cowling consists of a group of four quick detachable panels fastened to supporting rings attached to the rocker box covers of the engine. Hydraulically operated flaps for controlling exits of cooling air are provided at the upper rear section of the secondary engine cowling.

Normal fuel load is carried in two self-sealing fuel tanks fitted with baffles to minimize surge; a main tank is installed between the wing hinge supporting bulkheads and an auxiliary tank is installed directly aft of the rear wing hinge supporting bulkhead. To prevent vapor lock at high altitude, both tanks are equipped with electrically operated booster pumps which are of sufficient capacity to insure adequate fuel pressure and flow in the event of failure of a type G-9 engine-driven fuel pump.

External fuel is carried in combat or ferrying tanks attached to bomb shackles in the belly and/or wing. These tanks are pressurized by the exhaust of the vacuum pump.

Lubricating oil is carried in a hopper-type magnesium tank of 28.6 U.S. gal capacity, strapped to supports on the engine mount. A pendulum is incorporated in the tank to insure adequate lubrication for inverted flights of limited duration.

Oil temperature is regulated by two radiators mounted below the engine; surge valves permit cold oil to bypass the radiators. Each radiator has an air scoop with an outlet door controlled by an electrically operated motor; the doors operate simultaneously from the one motor.

The supercharging system of the P-47 airplane is designed to supply 52" Hg manifold pressure (considerably more for War Emergency Power) to the engine up to stratosphere levels.

Diagram of Supercharging System

The exhaust driven turbine is approximately 22 ft aft of the propeller and is supported by a ring attached to the lower longerons. The exhaust gases are collected by two rings, one each for the left and right bank of cylinders and directed to the nozzle box of the turbine through shrouded exhaust piping along either side of the airplane beneath the fuselage. Spent gas escapes through a stainless steel flight hood which extends below the fuselage.

Ram air is piped through ducts under the fuselage extending from the primary cowling to the impeller-inlet of the turbine; after supercharging, the air is scooped to the intercooler then piped along either side of the fuselage and directed to a single duct above the carburetor.

A considerable volume of the "ram" is conducted to the intercooler in order to lower the temperature of supercharged air. Electric-motor-controlled doors of the intercooler exit ducts on both sides of the fuselage vary the flow of cooling air through the intercooler.

Supercharging is controlled to maintain the manifold pressure value selected by the pilot, by means of an oil operated supercharger regulator. The regulator, through linkage, varies the position of waste gates in the exhaust pipes just aft of the collector rings and thus controls the volume of exhaust gases directed to the nozzle box of the turbine. The position of a piston in the regulator, is balanced by exhaust pressure and a compression spring; the spring is mechanically loaded to correspond to the desired exhaust pressure valve by a supercharger lever in the cockpit. When the exhaust pressure varies from the selected value, the piston moves in the direction of the greater pressure and opens a port admitting pressurized lubricating oil to that chamber of the regulator which will affect the movement of the waste gates in the proper direction to balance the piston at the neutral position.

Interconnected Engine Controls

In order to minimize pilots attention to engine controls, the propeller, boost, and throttle levers of the P-47 may be interconnected and moved as a single lever with power and rpm correlated through the full range of the control quadrant. Correlation is mechanical. The propeller lever is correlated by the use of a cam; throttle and boost levers are correlated by adjustment of conventional push-pull rods.

Controls may be disconnected by releasing a simple spring loaded clip on the throttle lever.

Water lnjection Used

Diagram of Water Injection Regulator & Hydraulic System

To meet the demands for a higher emergency rating and to safeguard the engine from detonation when operated at considerably above the military power, water injection has been applied to the Thunderbolt's power plant. Water is pumped from a 30 gal tank strapped to the firewall and is admitted through a water regulator by operation of a solenoid valve. Pressurized water beyond the regulator resets carburetor mixture so that the fuel-air ratio is decreased thereby increasing power without a corresponding rise in manifold pressure. The higher increase in power, however, is developed by high manifold pressure accomplished through a boost reset mechanism also actuated by water pressure; the reset overrides the supercharger regulator setting of the waste gates, therefore permitting the turbo to develop the higher rpms required to maintain the War Emergency Rating manifold pressure.

Main Landing Gear

The full cantilever, hydraulically-controlled main landing gear of this airplane consists of independent right and left hand units of air-oil combination shock strut assemblies and extra high pressure cast magnesium wheels of drop center rim type.

A box-like structure of four cast magnesium plates, two of which serve as trunnions, supports each shock strut assembly. The box assembly fits into a well, formed by rib 86, rib 104, and the landing gear auxiliary spar, and is supported by four bolts through each of the ribs and adjacent plates.

Before the gear starts its retraction cycle, hydraulic pressure is applied to withdraw a nitrided steel downlocking pin from a housing in the downlocking arm of the strut; a mechanically operated sequence valve is then opened to admit pressure to the landing gear retraction cylinder.

During retraction, the shock strut piston is telescoped to the bottoming position so that at the completion of the "up" cycle the gear will fit into a well which is 9" shorter than would be necessary for conventional "up-positioning" of the gear. The telescoping is accomplished by the "geometry" of the mechanism which employs a shrinkage strut or rod; one end of this rod is attached to the shock strut piston and the other pivoted about an axis outboard and below that of the landing gear pivot axis. Geometrically, the shock strut and shrinkage strut can be considered as radial elements from different radii terminating at the lower end of the shock strut piston housing and the lower end of the piston respectively. The radii (landing gear and shrinkage strut pivot axes) are spaced so that the difference in the loci at approximately 0? (landing gear down) is almost zero and the difference between loci at approximately - 90? (landing gear up) is about 9".

As the piston telescopes, the air in the air-oil chamber of the shock strut is displaced by the oil and is transferred to an auxiliary air chamber above the air-oil chamber in the strut. An air valve, actuated by a push rod following a cam track above the strut, opens the auxiliary air chamber.

Armament

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.

Ammunition of more than 350 rounds per gun may he carried in the bays just outboard of the gun bays.

Bombs and rocket tubes are supported in conventional shackles under the wing.

The pilot is protected from enemy gun fire by face hardened 3/8" armor plate located in the forward and aft ends of the cockpit. The area above the front armor plate is protected by 1" bullet resistant glass. "

There is tons more to read to run don't walk





Happy hunting and check six!

Tony Ascaso, RN

XyZspineZyX
09-16-2003, 01:27 AM
I recall back when some FW drivers were whining about the oneshot engine seize the conventional wisdom seemed to conclude that what was happening was that the prop gear box was getting hit, seizing the whole thing.

Afaict from flying radial engined FWs a whole whole lot is that once in a great while a bullet will find its way into a critical spot that seizes your engine, and almost as rarely it will find a spot that smokes your engine and causes it to fail after awhile, but the overwhelming number of hits do basically nothing.

Just keep in mind that the pilots that get hit by 20 rounds and come back all say omg omg that thing really took a ton of hits and I never even noticed, but the pilots that got downed by 1 bullet don't come back to say anything.

Reminds me of one time online I was hosing some guy from behind and doing nothing, broke off, came back and took a snap shot from near HO high deflection and got a PK and he starts talking like there was something wrong that he got killed by just 1 bullet lol. It only ever takes 1 bullet to bring any plane down, weather or not it was hit with other bullets doesn't usually matter (well, for taking off wings the cumulative effect matters, but even so I have taken off wings with a single round so it doesn't always matter), you may hose it with 3 seconds worth of 8 guns to get the engine on fire, but it really only took 1 bullet from all of those fired to do the job (I have reason to believe that the DM is such that armour can be peeled away in a sense, so it may actually require more than 1 in some cases).

The very first time I ever fired at a P47 I flamed his engine with 1 burst, I have been hosing down P47s ever since and cannot recall flaming an engine since (smoke a couple though).

XyZspineZyX
09-16-2003, 01:37 AM
Thanks, tascaso! That is a really good read there!

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XyZspineZyX
09-16-2003, 03:52 AM
Time and time again I have read that the P47 motor could take on a sh*t load of lead and keep run'n strong. You see the same thing on Discovery Wings cable network.

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XyZspineZyX
09-16-2003, 04:30 AM
Discovery Wings is not gospel, it's usually right but then again...

Thanks Tenmike for that info. That's pretty much my recollection of the issue. S!

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XyZspineZyX
09-16-2003, 04:56 AM
"Time and time again I have read that the P47 motor could take on a sh*t load of lead and keep run'n strong. You see the same thing on Discovery Wings cable network."

But then again, the pilots that flew P-47s which engine's could not take that shi*load, don't come back to testify "the P-47 engine block ain't that special", do they?

The thing is, people have to understand the average gamer meets more enemies, fights more of them, gets shot at more often, and gets shot down more often by enemy planes in a single hour, than what real life pilots would meet in a single week. For people who enjoy two~three hours of action in dogfighting rooms, they meet more enemy planes than what an average fighter pilot would meet in their whole tour of 25 missions.

What is to be seen in real life at an odds of 1 out of 1000, can be accelerated in a game to odds of 1 out of 100, or 1 out of 10 even, considering the totally different set of circumstances the arm-chair pilots meet. Would the real life pilots try all these superb rolling scissors, hot-shot maneuvers in combat? Would an enemy plane try and follow every move despite the risk it would bring? If that were the truth in real life, the attrition rate of combat pilots would be close to 1:1, and the casualty rate per mission also nearing 1:1 - every pilot who gets kills in a single mission, would be expected also to be killed in action in that same mission.

Considering even a super-ace like Hartmann would get only 1 kill out of three long missions, the average time a game pilot faces where an enemy plane is behind him is humongously longer than real life. We get shot at more often than probably all the total of pilots in a single Fighter Group got shot at in all their mission careers.

So what are the odds that a fluke shot will kill me? Considerably higher than a fluke shot will kill plane engine in real life.

..

Also we must be reminded, that the more complex a DM, the more the inconsistencies. The complexity of the DM means a lot of things can happen - and among them, fantastic shots which will render an engine useless. Taking "shi*load" of shots, is something to be remembered even by real-life standards, as it was rare. We would go on to comment a P-47 was a rugged plane from one instance, not thinking of the many more instances where the 'ruggedness' failed to save a pilots life.

Also, would the ruggedness mean a plane is combatworthy even in that condition? Perhaps, in the case of really light damages. However, in real life when an engine was hit and the pilot is aware of this fact, he would retreat immediately, calling out for help as he extended away. Do they fight and squirm like we do in games? Hardly.

The assigned wingman would escort him out of battle until he reaches a safe distance to head back home, and the 'ruggedness' would pay off when the damaged fighter would reluctantly, but still stably remain under the control of the pilot, who is nursing his craft and hoping it does not fail. When they make it back home, they get to tell the tale of the rugged fighter. However, for every one tale, there are many more untold tales of how the case was opposite.

Often, game pilots are shot at, receive damage, and they expect to be able to fight, turn the odds, hope the plane remains combatworthy long enough to get their 'payback'. The truth is, in many cases where an enemy plane firmly holds your six and gets a shot in to you, you are lucky if you survive his attack. No amount of toughness will stand up to a determined attack, and the only thing which will save you is your friends. If they are not too late, they will clear the enemy of your six(in the game, however, target-fixated bandits rarely let go of their prey despite they know other enemies are rushing behind him), and you'll get a chance to nurse your plane back home.

And, when that happens, only then it's a time to discuss 'ruggedness'. Will your plane make it back or not?


Having a bogey behind you shooting your nuts off, and discussing the 'ruggedness' of an engine in that situation, is totally out of the question.



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Due to pressure from the moderators, the sig returns to..

"It's the machine, not the man." - Materialist, and proud of it!

XyZspineZyX
09-16-2003, 05:02 AM
kweassa that was a very astute post ....S!

U.S. infantry 84-91

XyZspineZyX
09-16-2003, 05:04 AM
Well said, kweassa! Thats exactly what I'm trying to get across!

Considering the P-47's current survivability, its quite amazing - it CAN take damage that would destroy a lesser AC and still take out its attacker.

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