P-47 - Fuselage extension: but how big was it?

[Juanita]

Been doing a bit of indepth research on the P-47.
During the production of the P-47C an extension was inserted at the firewall which was part of the 'Quick Engine Change' package. This added length to the fuselage which improved the handling characteristics.

The question is: how thick was this extensions? Some sources quote 8" but some quote 13"!
The station diagrams are no use because they simply quote "Stat 101 5/8 FWD" and "Stat 101 5/8 AFT" (ie the same number for 2 station positions)...and they don't give the distance between the two.

Wondering if anyone knows what the thickness of the extension was...preferably and exact dimension (like seriously, was it exactly 8 inches?)

Juanita

 

[fubar57]

In "Thunderbolt-From Seversky to Victory" by Warren Bodie, 1994, the length of the C-RE is given as 35' 5", for the C-1-RE the length is 36' 1". One thing I can't find is information about the Quick Engine Change. How long did it take to change out a P-47 engine using this?

 

[MIflyer]

The little William Green book says that the P-47C had the fuselage extended 8 inches at the firewall and a new engine mount employed.

Now, note that the fuselage was extended 8 inches, but the engine mount is bolted to that and we don;t know what effect the new engine mount had, if any

The P-47B was 35 ft 3.25 inches long and the P-47C-5-RE was 36 ft 1.75 in long, That is a difference of 10.5 inches, not just 8! So I can only assume the fuselage was extended 8 inches and that the new engine mount added another 2.5 inches.

Thanks for asking! I had wondered about that.

By the way, the P-47M and N had the later C series engine and were 36 ft 4 inches long.

Now, the next question is: Which P-47 model kits have the correct length?

 

[fubar57]

From the same book..."Maneuvering performance of the long-nose version was significantly improved by the 8 inch fuselage extension. Contrary to other information, it was merely a bonus and not the reason for lengthening......"

 

[Shortround6]

The little William Green book says that the P-47C had the fuselage extended 8 inches at the firewall and a new engine mount employed.

Now, note that the fuselage was extended 8 inches, but the engine mount is bolted to that and we don;t know what effect the new engine mount had, if any

The P-47B was 35 ft 3.25 inches long and the P-47C-5-RE was 36 ft 1.75 in long, That is a difference of 10.5 inches, not just 8! So I can only assume the fuselage was extended 8 inches and that the new engine mount added another 2.5 inches.

Thanks for asking! I had wondered about that.

By the way, the P-47M and N had the later C series engine and were 36 ft 4 inches long.

Now, the next question is: Which P-47 model kits have the correct length?

Is it possible that planes that used the Curtiss Electric propellers varied in length from the planes that used Hamilton standard Hydraulic propellers?

 

[MIflyer]

The difference in propeller length occurred to me, but based on photos I do not see a significant difference. Some of the props used on some airplanes, like the F8F and AD-6, had no dome in the front but on the P-47's they all had domes. Whether the domes on Curtiss versus Ham Standard were of the same length, I do not know.

 

[GrauGeist]

The Curtiss prop had it's gearing in the cover ahead of the prop hub, the H-S prop had it's gearing in a bell behind the prop hub - so I'm not sure if there would really be much of a difference between the two.

 

[Ivan1GFP]

Hello All,

This is one of those issues that has bothered me a bit also. It becomes especially important if one is attempting to build a 3D model.
Not that my references are necessarily better than anyone else's but the numbers I have are a bit different.
According to my notes, the P-47B was 35 feet 4 3/16 inches long.
The length for the P-47C and later is noted as 36 feet 1 inch.
The length of the P-47D-30 from a diagram from the Warbird Tech book is shown as 36 feet 1.75 inch.

I believe that Shortround6 is correct. There IS a length difference between the Curtiss Electric Propeller and Hamilton Standard Propeller.
The C-E propeller hub is slightly longer. From the measurements we have seen quoted here, I believe 3/4 inch longer is a pretty good "Assumption". About a year or so ago, I actually spent a fair amount of time trying to figure out the differences in propeller dimensions on various models of Thunderbolt. It was obvious when scaling from photographs that the C-E hub fairing was longer but the exact number was not certain.

Hope this helps.
- Ivan.

 

[MiTasol]

The Curtiss prop had it's gearing in the cover ahead of the prop hub, the H-S prop had it's gearing in a bell behind the prop hub - so I'm not sure if there would really be much of a difference between the two.

Actually both have the gearing forward of the hub - see below from two of my HS prop manuals.
As far as I know I do not have any prop dome dimensions so cannot comment. The HS pitch change unit is far heavier than the Curtiss unit, not that that is part of this question and I do not have an HS unit laying around to measure

 

[wells]

The maintenance manual gives the following information,

Overall Length RP-47B, RP-47C and G to AF42-24940; 35' 4-3/16"
Later models; 36' 1-3/8"

Fuselage Length without engine mount; 306-1/4", later models 314-1/4"
Fuselage Length with engine mount; 430-7/16", later models 438-7/16"

 

[waroff]

The question is: how thick was this extensions? Some sources quote 8" but some quote 13"!
The station diagrams are no use because they simply quote "Stat 101 5/8 FWD" and "Stat 101 5/8 AFT" (ie the same number for 2 station positions)...and they don't give the distance between the two.

The planform gives stat 85/sta101"5/8 => 16"5/8 and 24"5/8
the distance between two sta 101"5/8 is 8"

 

[waroff]

The maintenance manual gives the following information,

Overall Length RP-47B, RP-47C and G to AF42-24940; 35' 4-3/16"
Later models; 36' 1-3/8"

factory drawings and EMM drawings give
overall length
P47B & C R2800-21 engine = 35' 5"3/16
P47 C & up = 36' 1" 3/4