Canberra B.2 B.6 B(I)6

[canberra kid]

Over on another post Dave @Rabbit Leader and @Black Knight asked if I could do a post outlining the differences between the early versions of the B.6/ B(I)6, and also the B.2. I will probably deal with the B.2 separately. First let's dispel the misconception that the B.6 was longer than the B.2, that is if anyone still thinks it is? This has come about from the fact that as I will tell in more detail in a bit, the B.6 was in a sense a direct development of the B.5. The one and only B.5 VX185 was originally destined to be the second PR.3 prototype and the aircraft sireal was issued as such, but before construction had started or progressed very far she was reassigned to be the B.5 Target Marker prototype, which in turn was a development of the B.2, and save for a modified prone position in the nose was identical externally to the B.2.

As I said, the B.6 was a development of the B.2 incorporating improvements developed and trialled on the sole B.5 for it's record breaking dubbel transatlantic crossing in a single day. These modifications consisted of a 'wet wing' this incorporated fuel tanks in the wings, anti skid wheel brakes and underwing hardpoints for the carriage of external weapon loades and more powerful Avon 109's. It was found during flight testing of the B.5 it was found that the new more powerful Avon 109's were just a bit too much for the standard B.2 design to cope with and it was found that the back end of the aircraft was prone to flap about a bit, which as you can imagine is not exactly what you'd want! To absorb some of the extra energy transferred to the airframe by the more powerful Avon's the rear fuselage had a skin strengthening panels 'scabbed' over the rear fuselage. This modification was also found on the longer PR, Canberra's and all mark's using the Avon 109's apart from the GAF built Mk.20's. On introduction into service the basic B.6 had a 'blunt' intake starter cartridge fairing on the Avon's, the reason for this is as yet, to me at least a mystery, but they were later modified to the later more usual pointed type, this modification appears to have been carried out at the same time as the fuel vent was moved from the right side of the fuselage just above the trailing edge of the wing to the more familiar position under the tail plain. Another early mod was the introduction of mud guards on the nose wheel and a frangible hatch for the navigator and bomb aimer's compartment this was a wight saving measure and did not include the two windows. This mod proved to be troublesome and was quickly deleted but it reappears later before being abandoned altogether, although it did live on as a permanent fit on the D.10 and U.14. 

The B(I)6, the 'I' standing for interdictor was externally identical to the B.6 and followed the same modification path, specific to the Interdictor role was the introduction of a 4x 20mm Cannon pack. THis was situated at the rear of the Bomb bay, the fitting of the gun pack called for the fitting of specially modified bomb bay doors. This is an area that also appears to have caused some confusion with some publications serguesting the doors were split in half with only the part in front of the gun pack opening and closing, whereas in reality the doors were full length with a cut out which closed around the gun pack. The B(I)6 also received some minor mod's to the airframe but nother worth getting too excited about. 

Well I think that's covered everything I can think of for now, feel free to pitch in with any thoughts, questions or suggestions.

 

John             

                          

[huvut76g7gbbui7]

Good solid info there John.

It's amazing how many myths there are about Canberra (and Meteor) lengths.

I remember VX185's original nose being on display at East Fortune some years ago. Where is it now?

Richard

[canberra kid]

On 5/6/2018 at 8:01 PM, Scimitar said:

Good solid info there John.

It's amazing how many myths there are about Canberra (and Meteor) lengths.

I remember VX185's original nose being on display at East Fortune some years ago. Where is it now?

Richard

Thanks Richard, they are both complex subject's so I suppose it's not too surprising? Yes the B.5 nose is still north of the border, I should make the efort and go see her again.

John

Edited May 11, 2018 by canberra kid

[huvut76g7gbbui7]

Here's a pic which shows the bomb aimer's window. Sorry for slight thread drift John!

Note part of the Brabazon's undercarriage in background.

[canberra kid]

The B. 5 was a lovely looking Canberra, we are very lucky the nose was saved. 

John

[Max Headroom]

Was that nose removed so that it could be replaced with the B.(I)8 style offset one?

 

Trevor

[canberra kid]

2 minutes ago, Max Headroom said:

Was that nose removed so that it could be replaced with the B.(I)8 style offset one?

 

Trevor

Yes indeed it was Trevor, I don't know how it managed to escape the scrap man's axe but I'm reall glad it did!

John

[71chally]

14 hours ago, canberra kid said:

Well I think that's covered everything I can think of for now, feel free to pitch in with any thoughts, questions or suggestions.

 

John                                      

Apart from that most perpetrated myth by model kit manufacturers, that B.6s have the same main wheels as B.2s!

 

Just a thought, I was under the impression that B.2s did have the mudguards?  These being fitted after early experiences with take-offs from grass causing a lot of mud and debris to be flung into the nose bay.  I used to have the nose wheels from WD954 an early B.2 which did have mudguards, but that's not to say that the u'c was replaced over at some stage

 

Nice precis John - looking forward to the fuselage and wing illustrations!

[canberra kid]

On 5/7/2018 at 9:34 AM, 71chally said:

Apart from that most perpetrated myth by model kit manufacturers, that B.6s have the same main wheels as B.2s!

 

Just a thought, I was under the impression that B.2s did have the mudguards?  These being fitted after early experiences with take-offs from grass causing a lot of mud and debris to be flung into the nose bay.  I used to have the nose wheels from WD954 an early B.2 which did have mudguards, but that's not to say that the u'c was replaced over at some stage

 

Nice precis John - looking forward to the fuselage and wing illustrations!

Hi James 

 

Indeed one wheel fits all, not! You would have thought that the mudguards would have been thought of quite early on. but apparently not. As yet I can't find the UK mod number but it's in the Mk.20 AAP. In fact there is two, as follows, these are direct quotes.

Canberra Modification. C.33  24/6/1953. Nose wheel, introduction of mud shield.

Canberra Modification. C232 29/6/1954. Nose wheel introduction of Mudguard.

Some dates for B(I)6 mod's the first is the vet mast mod this should give a good indication of the date for the change from the Avon 109 with blunt intake to pointed.

Canberra Mod 1728 1/6/1956, To move fuselage tank vent to a position feather aft to prevent contamination of camera window and build up of fuel vapor in the rear fuselage under the tail plane. 

Canberra Mod  2187 18/4/1961 Introduce a frangible hatch over the Navigators position suitable for the fitment of a sextant.

Canberra Mod 3355 26/10/1962 Introduction of white anti collision lights.

Canberra Mod 3706 31/1/1966 Introduction of metal hatch over the Navigators position suitable for the fitment of a sextant.

 

John

    

[Rabbit Leader]

John @canberra kid, sincere apologies for not thanking you and commenting earlier. Due to timezones I did read your original post through squinting eyes one night and thought best to respond when I fully woke up. It was a work day and I’m afraid it just slipped my mind.

 

This is a great start and hopefully we can all build on it in order to have a concise reference piece. It’ll be great to finally dispel the many myths and hopefully unlock some unknown Canberra secrets in order to make our models just that little bit more accurate. 

 

Cheers.. (and thanks once again).. Dave

[canberra kid]

A very nice company photo of an early B(I)6 note the blunt starter cartridge fairings and lack of fuel vent mast.

I'm not sure if this is a six or a 2 but you can see the frangible Navigators hatch. Also of note, the pilot's WW.2 style leather helmet!

John 

 

 

 

  

[Graham Boak]

The B.2 and B.6 may have had the same wheels, but they had different brakes.  My first job at Warton was extending the Canberra Operating Data Manual for hot and high airfields, and I soon learned that for all the multiplicity of marks there were just two different engines and two different brakes, which made life a lot easier.

 

To clarify that, the PR.9 was a Shorts aircraft and hence someone else's problem, and away from the airfield the T.17 had additional power offtakes that reduced its performance - but that was a different part of the ODM.

[canberra kid]

 

20 hours ago, Graham Boak said:

The B.2 and B.6 may have had the same wheels, but they had different brakes.  My first job at Warton was extending the Canberra Operating Data Manual for hot and high airfields, and I soon learned that for all the multiplicity of marks there were just two different engines and two different brakes, which made life a lot easier.

 

To clarify that, the PR.9 was a Shorts aircraft and hence someone else's problem, and away from the airfield the T.17 had additional power offtakes that reduced its performance - but that was a different part of the ODM.

That must have been interesting Graham, I will have to take a look sometime to see how many export versions got the 'Big' wheel with the anti skid brakes, I know the FAA Mk.62's did and I would venture a guess that the ones that came back to Samlesbury for refurbishment my have done? 

John

[David Womby]

Any advice on the colour of the intake trunking on a black/MSG B2, please?

 

David

[canberra kid]

On the subject of wheels, when I was looking through the two volumes of the B.6/B(I)6 mod list I came across this,

Dunlop Mod. M828-intro

Can Mod/4481 12/12/1968

Canberra B.6 and B(I)6 Aircraft

Main Undercarriage-To introduce Main Wheel AH.52692(27A/1450713) in place of AH.52325(27A/4948) or AH.51337(27A/4217) and New Inner Tube DT/1609(27A/1450834)

So this got me thinking, in the old Airfix B(I)6 kit the main wheel is of a diferant type to say the ones in the PR.9 B(I)8, they have a hole in each 'spoke' rather than one in every other 'spoke'. I did recall seeing a wheel of this type in a photo, so I had a look at my B.6 photos and yes there they were, a lot of them had the Airfix wheel! The following photo shows what I mean, I've put a red spot on the left wheel where the other holes would be on the pre mod wheel. You may also just be able to make them out on this photo of WT369?

 

This information also, I think explains why the Martin built Canberra had a diferant nose and main wheel to her British sister, if the wheels were Dunlop, Martin ether couldn't or didn't want a licensing agreement for the wheels and went with one of their own design.

 

John    

 

  

 

Edited May 11, 2018 by canberra kid

[canberra kid]

3 minutes ago, David Womby said:

Any advice on the colour of the intake trunking on a black/MSG B2, please?

 

David

Hi David the first few inch 6(?) local camouflage colour the the rest HSS. 

John

[David Womby]

7 minutes ago, canberra kid said:

Hi David the first few inch 6(?) local camouflage colour the the rest HSS. 

John

Thanks.  Now all I have to do is work out how to paint that!!

 

David

[huvut76g7gbbui7]

Do you have a picture of a B2 mainwheel off the aircraft like your photo in post 15?

Did the T17 keep the B2 wheels for it's entire service do you know?

Thanks.

[canberra kid]

12 minutes ago, David Womby said:

Thanks.  Now all I have to do is work out how to paint that!!

 

David

What I have done before David is paint it all HSS and use decal strip for the camo. 

 

John

[71chally]

11 minutes ago, Scimitar said:

 

Did the T17 keep the B2 wheels for it's entire service do you know?

Thanks.

Yes, you can just make out the B.2 spoked type in this shot.

Canberra T.17A WJ607 EB by James Thomas, on Flickr

 

As far as I'm aware all the British service B.2 derivatives kept those B.2 spoked type mainwheels.

Edited May 9, 2018 by 71chally

[David Womby]

2 minutes ago, canberra kid said:

What I have done before David is paint it all HSS and use decal strip for the camo. 

 

John

Many thanks.   I don't think I would have thought of that.   What colour for the starter bullets, John?

 

David

[canberra kid]

8 minutes ago, Scimitar said:

Do you have a picture of a B2 mainwheel off the aircraft like your photo in post 15?

Did the T17 keep the B2 wheels for it's entire service do you know?

Thanks.

Hi Richard

Yes the T.17 kept  the B.2 wheel, these are the best photos I can find right now but I have more if you need?

John

 

[canberra kid]

1 minute ago, David Womby said:

Many thanks.   I don't think I would have thought of that.   What colour for the starter bullets, John?

 

David

That would be HSS too David

John

[71chally]

These are the B.2 spoked type main wheel

Front

 Rear

 

The wheel hub diameter is 19 inch on B.2 types, 21 inch on B.6 and later.

Tyre section and overall diameter remain the same at 13.5 x 43 inch.

[canberra kid]

34 minutes ago, Scimitar said:

Do you have a picture of a B2 mainwheel off the aircraft like your photo in post 15?

Did the T17 keep the B2 wheels for it's entire service do you know?

Thanks.

Richard have a look on my site too at the Wheels and Well's album Wheel's and Well's album

 

John