General Electric/Allison J-33 engine - Bell XP-83 engine installation

[John R]

I have just started an Anigrand Bell XP-83 and found an error. In the engine nacelle there is a part representing the compressor face. There is no such thing in the a/c as it has a centifrugal compressor. Pictures of the J-33 show a mass of pipes and equipment before the intake. When installed in the a/c was this protected by some sort of bullet fairing or was it left out in the breeze? A cutaway drawing in Steve Pace's 'X Fighters' book suggests the latter.

Can anyone please enlighten me?

John

[Navy Bird]

Really hard to tell, but this photo doesn't seem to show a bullet fairing.

 

 

 

Cheers,

Bill

[canberra kid]

The 

On 1/19/2021 at 8:21 PM, John R said:

I have just started an Anigrand Bell XP-83 and found an error. In the engine nacelle there is a part representing the compressor face. There is no such thing in the a/c as it has a centifrugal compressor. Pictures of the J-33 show a mass of pipes and equipment before the intake. When installed in the a/c was this protected by some sort of bullet fairing or was it left out in the breeze? A cutaway drawing in Steve Pace's 'X Fighters' book suggests the latter.

Can anyone please enlighten me?

John

John, the J.33 looks a lot like the Nene used in the Meteor, in the Meteor the front of the engine is very much exposed to the airflow with just a small section of wing in front.

 

John

[canberra kid]

@John R I've done a bit more digging and I've come up with this which suggests it was just all the plumbing at the front, it's a centrifugal engine so no compressor blades. There is a small aerodynamic fairing that is visible in this and a few photos. Later, production(?) aircraft appear to have had a splitter plate.

 

 

I hope that helps?

John

 

[Magpie22]

John,

That info you posted is applicable to the YP-59A, which was powered by a GE Model I-16.

 

The GE Model I-16,( J-31), and GE Model I-40, (J-33), ar quite different beasts. The only thing that they have in common is that both utilise a double-sided centrifugal compressor. The J-33 was larger D=50" compared to 41" and L=107" compared to 72".

 

Another common feature was that both had their ancilliaries mounted at the front of the engine, so that the protective fairing for those ancilliaries and their connections, that Bell used on the P-59A, was probably also utilised on the P-83. However, there is no guarantee that it looked exactly the same as that on the P-59A.  Knitpicking I know, but may be well worth bearing in mind.

 

Peter M

Edited January 23, 2021 by Magpie22

[John R]

My first reaction was 'Wow, where did you find that picture?' then I realised it was the P-59. However on the Secret Projects site someone has come up with a lot of things I did not wish to know, namely that there are some basic errors in the fuselage in the Anigrand kit (Surprise!)

https://www.secretprojects.co.uk/threads/bell-xp-83-model-40.8271/page-2#post-434598

However in addition to those he pointed out that in some pictures of the XP-83 you can just make out a horizontal line in the centre of the intake which is where the fairing would be if it had one similar to the XP-59 so your first picture is a great help

John

[Navy Bird]

21 hours ago, John R said:

However in addition to those he pointed out that in some pictures of the XP-83 you can just make out a horizontal line in the centre of the intake

 

I think you can see that in the photo I included in my post above. I tried to increase the gamma in that photo to try and bring out any other details inside the intakes, but was not successful. The horizontal lines in my photo seem much wider (when compared to the width of the intake) than the fairings in John's P-59 pic which is why I initially thought they might be piping of some sort.

 

Cheers,

Bill

[John R]

Here is another view of the intake, which has been 'dodged' in Photoshop, which seems to show some sort of fairing but not the same as that of the XP-59

All that can be said is that it doesn't show valves, pipes and wiring

John

[Navy Bird]

FOD cover?

 

Cheers,

Bill

[canberra kid]

15 minutes ago, Navy Bird said:

FOD cover?

 

Cheers,

Bill

That's what I was thinking Bill

[John R]

I thought about FOD cover but it looked a bit too far inside the intake.

Here's another view where it does appear to have a FOD cover

John

[John R]

Just found this. It's faint but it looks like a fairing over the front end of the engine ending where the air enters the engine.

 

[Tailspin Turtle]

1 hour ago, John R said:

Just found this. It's faint but it looks like a fairing over the front end of the engine ending where the air enters the engine.

 

 

That’s a possibility. Because it was a centrifugal flow engine, the air wasn’t rammed into the engine but basically sucked into it from behind the accessory package in what was essentially a plenum chamber. Google J33 images...