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    • Mike

      PhotoBucket are no longer permitting 3rd party hosting   01/07/17

      As most of you are now painfully aware, Photobucket (PB) are stopping/have stopped allowing their members to link their accumulated years of photos into forums and the like, which they call 3rd party linking.  You can give them a non-refundable $399 a year to allow links, but I doubt that many will be rushing to take them up on that offer.  If you've previously paid them for the Pro account, it looks like you've got until your renewal to find another place to host your files, but you too will be subject to this ban unless you fork over a lot of cash.   PB seem to be making a concerted move to another type of customer, having been the butt of much displeasure over the years of a constantly worsening user interface, sloth and advertising pop-ups, with the result that they clearly don't give a hoot about the free members anymore.  If you don't have web space included in your internet package, you need to start looking for another photo host, but choose carefully, as some may follow suit and ditch their "free" members at some point.  The lesson there is keep local backups on your hard drive of everything you upload, so you can walk away if the same thing happens.   There's a thread on the subject here, so please use that to curse them, look for solutions or generall grouse about their mental capacity.   Not a nice situation for the forum users that hosted all their photos there, and there will now be a host of useless threads that relied heavily on photos from PB, but as there's not much we can do other than petition for a more equitable solution, I suggest we make the best of what we have and move on.  One thing is for certain.  It won't win them any friends, but they may not care at this point.    Mike.
AnonymousFY21

Canberra Reference Thread

62 posts in this topic
OK, you tech heads, why do you see so many photographs of Canberras on the ground with bomb doors open?

It's been suggested that it's for ease of servicing but I wonder if it's a hydraulic issue much the same as flaps on an f-4 drop when power is off?

Rich,

Not having worked on a fully working airframe and Im still studying the hydraulic system, I would hazard a guess at hydraulic pressure dropping off, as you well know theres two whopping great rams that operate the door mechanism, and my reason for this is 773 has no hydraulic system pressure and I can freely open the doors with my hands and they be ruddy heavy and would assume gravity would have a field day with them. Anyone got anything else?

Does anyone know if any of the Vietnam B57G operational warloads would have included GBU 8 EO bombs?

My knowledge of B57G weapon loads is rather poor, however, the B57 references I do have only mention iron bombs(B57B) or 500lb Mk2 Laser Guided Smart Bomb(B57G) So, does anyone else have anything to add to this? Ollie perhaps? (You know more about the G than I do)

Bexy

Edited by bexwh773
after thoughts

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Rich,

Not having worked on a fully working airframe and Im still studying the hydraulic system, I would hazard a guess at hydraulic pressure dropping off, as you well know theres two whopping great rams that operate the door mechanism, and my reason for this is 773 has no hydraulic system pressure and I can freely open the doors with my hands and they be ruddy heavy and would assume gravity would have a field day with them. Anyone got anything else?

That's my take on it too so I'll do mine open I think.

Cheers Bexy

R

My knowledge of B57G weapon loads is rather poor, however, the B57 references I do have only mention iron bombs(B57B) or 500lb Mk2 Laser Guided Smart Bomb(B57G) So, does anyone else have anything to add to this? Ollie perhaps? (You know more about the G than I do)

Bexy

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Looking forwards to it Rich, TBH I cant think of any other reason for them to be open, and having spent 3 weeks fighting with 773 to get her doors running freely (with shares in WD40) it would make sense, epsecially as her emergency release cable had been cut(like 99.9% of her cables & rods :angrysoapbox.sml: )

The rams operate in an up and down motion forcing side rods out to open & close the doors....... see piccy:

scan00045.jpg

And from that, I reckon to about 99.9% certainty, once the pressure backs down, gravity would pull them apart.

Bexy

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I don't know Canberras and I don't know airframes. But I do know hydraulics.

From Bex's scan I can see that the doors are open and shut by a double action ram. This would normally have its hydraulic flow controlled by a shuttle valve.

I feel that when the hydraulic pressure bleeds off the doors might start to open. This would become more prevalent as the airframe and the hydraulics got older. On a nice new 'tight' hydraulic system pressure would remain in the system for days.

Just my take as an ex engineer. I'll probably be proved wrong :)

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I don't know Canberras and I don't know airframes. But I do know hydraulics.

From Bex's scan I can see that the doors are open and shut by a double action ram. This would normally have its hydraulic flow controlled by a shuttle valve.

I feel that when the hydraulic pressure bleeds off the doors might start to open. This would become more prevalent as the airframe and the hydraulics got older. On a nice new 'tight' hydraulic system pressure would remain in the system for days.

Just my take as an ex engineer. I'll probably be proved wrong :)

That arrangement is fore & aft of the bomb bay Sis, and the way youve explained it, makes more sense :thumbsup2:

Bexy

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Hi all

I'm back looking for more help!

Does anybody have a copy of the instructions from the Airfix Canberra B(1)6 kit from a long time ago. The kit number is 9 05012.

Thanks in advance

Antony

edit for basic spelling mistakes

Edited by antony robertson

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Hi all

I'm back looking for more help!

Does anybody have a copy of the instructions from the Airfix Canberra B(1)6 kit from a long time ago. The kit number is 9 05012.

Thanks in advance

Antony

edit for basic spelling mistakes

Antony,

If you havent got this already sorted, drop me a PM with your snail mail addy and I'll sort it for you.

Bexy

EDIT:

If anyone has any major problems and Im slow in answering, its because Im having yet more net access problems, so drop Mish a PM asking her very nicely to drop me a text on the ol mobile :thumbsup2:

Edited by bexwh773
After thought

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When Xtrakit brought out their PR.9 I bought one, completely forgetting I had the Matchbox kit. Then apon discoverying the 'lost' kit I did a comparison and found there was quite a difference in the tailplane sizes, the Xtrakit one being a lot smaller at the root chord (I'm guessing the Airfix one might be the same). I had found out that John Adams (Aeroclub) had contributed towards the Xtrakit model by providing some drawings so I asked him why the difference. He told me that the problem stemmed from the time the PR.9 was measured up for the Tech Manuals and was never discovered until recently but he says the Xtrakit (Airfix?) kit is correct. Later he sent me an email showing all the different variants and what the differences are between them.

Here is John Adams's notes on the Canberra:

Hi Robert

Putting it simply the Matchbox kit is quite wrong. The engine nacelles are the wrong shape, especially near the main spar. Also the fuselage is B(I)8 length (too short) and the Frog "8" is PR.9 length for good measure.

The tailplane chord on the Matchbox kit is wrong, but it is an error made in good faith. I found only a couple of years ago that the PR.9 AP Vol One has the wrong chord length given on the leading particulars page and this was taken as gospel by the late Maurice Landi, but someone at some time had messed up the AP dimensions.

The RAF never noticed and no-one ever checked it ,simply because the Canberra tail chord is always given as a projection to the a/c centreline and this is impossible to measure and it is a dimension which the RAF servicing types would never need to know. so it went unnoticed, until I got suspicious as I used to work on "9"s and started to project lines on photos. This convinced me of the error and it was confirmed by the Eng WO of 39 Sqn who kindly had some guys measure the chord at the root for me. This confirmed that the tailplane was the same as all other Marks. As the "9" has an untabbed powered rudder unlike all the other Mk's there is a slight rudder chord difference but not enough to worry about.

I provided the basic outline shape drawings to Sword, who did the Hannants one, as they were going to use Czech copies of the Aerodata 34 drawings which though beautifully drawn are inaccurate.

Thats it in a nutshell.

Regards

John

More of John's notes:

Hi Robert

The following might help to sort out Canberras.

Tech notes on Canberras

There seems to be some confusion over the differences between Canberra versions, perhaps this will help.

B.Mk.2

This was the first production Canberra, powered by the Avon 101 which had the single breech cartridge starter. Three crew ,Pilot, Nav and Observer / Bomb aimer, all in ejection seats, one at the front slightly offset under the goldfish “bubble top” and two in the back. The seats are Martin Baker Mk.1 CT or 2CT

There is also a folding Rumbold seat for a forth crew member with a chest parachute. The nose is glazed with an offset clear vis panel . this is the most common base for all later “funnies” like the T.11, T.17. TT.18 etc from frame One (which is not the first fuselage frame). Frame One is the frame were such as the PR.9 nose hinges and the T.17 nose is bolted on. It has radial spoked main wheels.

B57A

This is an Americanised B.2 built by Martin and was powered by licence built British, Armstrong Siddeley Saphire engines (J65) There were also local airframe production changes. The later 57’s are a totally different beast based on the Canberra airframe.

PR.3

A Photo /recce development of the B.2 (with single breech engines) but with a 14.5 inch extension for cameras inserted in front of the bomb bay which was smaller because of extra tankage and now termed a flare bay. It had a plain glazed nose.

T.4

This is the Trainer derivative of the B.2 and is recognised by an unglazed metal nose cap and the three EJ seats are re-arranged with two seats under the” bubble top” ( a pantomime to get into) and one at the back. It also has two DV windows in the “bubble”. The nose swings to one side for equipment access at frame One ( which is not the first frame). A version called the T.13 was exported of which early examples did not have ejection seats for the pilots.

Crew access to the T.4. A pantomime in several acts.

The ground crewman unlocks the base of the second pilots seat and swings it forwards so with no-one in the seat, it locks against the panel. (The top of the seat is hinged from a tubular beam so it swings in an arc). The normal first pilots seat is also attached to this beam on the port (Left) side but it has been moved further over to port

The Nav crawls past into the back and straps in.

The second seat is then swung completely further aft and locked at a steep angle so the way is clear for access to the port seat from the entrance door.

The first pilot climbs in past the stbd seat and straps in.

The second pilot now climbs in and straps into the aft angled seat, with his feet braced against the rudderbar plinth.

At a signal from him, the ground crewman now moves the seat back to it’s central base locking position, and all three crew are now in position and the crew side door can be closed.

At this point the Nav decides he does need a pee after all……..

At rest the T.4's elevators are depressed because of the locking bar fitted in the cockpit to keep the stick forwards to allow the swing seat operation. Conversely the bomber versions elevators are up when no elevator locks are fitted. The seats in the T.4 are 3CT's and are similar in layout to the Mk.2 in the navs position but don't have thigh guards. (Note They are not the same as a Mk.3 fitted in for instance, a Hunter)

B.Mk.6

The B.6 introduced the Avon 109 with a new triple breech starter this has a larger pointed centre body in the intake (early one is quite bulbous) also extra tankage in the wing leading edges. This made it heavier and called for larger stronger four spoke wheels .. Variations of the B.6 are the B.I.6 B.15 and B.16.

PR.Mk.7

This is the photo development of the B.6 and is a PR.3 layout with the Avon 109 and the B.6 tank wing. Two Crew. RN TT.22’s are converted PR.7s.

B.I.8

The “8” introduced the offset fighter canopy and at first glance appears radically different but is really a “boy racer” B.6 with a belly gun pack and wing pylons. The pilot has an EJ seat but the poor Nav does not . instead he was given a chest type parachute and take off seat at the back and a sidewards facing sliding seat in the nose which had extra windows. Both crew enter by the side door as on all previous Mks of Canberra. The canopy does not open.

The pilots EJ seat is mounted on the pressure bulkhead on an extension of the standard navs EJ rail so he is further aft and higher than in all previous Mk’s.

PR.9

This is the GT version but is really a PR.7 fitted with Avon 200 series engines which have a fickle Avpin liquid starter. The wings have extended tips and the chord is extended inboard of the engines on both leading and trailing edges. The pilot has 3CS EJ seat under a B.I.8 style canopy which does open (clam shell style) and the Nav has an EJ seat (type 4 QS) which is buried in the nose. Access to the Nav’s station is via a swinging nose (at frame One) and the Nav has two tiny windows, a periscope, also a forked stick (to stick notes in to pass them back) to communicate with the pilot.

The nose profile shape of all basic Canberras are the same regardless of which hole the pilot looks out of despite what some drawings suggest.

If you use this info anywhere I would appreciate it if you would credit me as this is my authorship.

As for the Frog PR.7 I would keep it a a piece of history. It's not very accurate. Every 1/72 scale Canberra has got the engine nacelles wrong as they do not "coke bottle" in to the wing section but are parallel between the front and rear spars.

Hope this helps

John

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Robert,

Thanks very much for including John's information here; it answers perfectly a lingering question I had about the 'triple breech starter' Avon 109 engine and how it differed from the earlier version. Of course, it's very useful for all the other details as well......

Cheers,

Andrew.

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A load cg reference diagram I'm using to determine where the new nacelles will go on my project, kindly provided by John Adams. John says this is for most short fuselage Canberras

LoadCg.jpg

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Ive just noticed, that on the Main Landing Gear Doors, Airfix call for parts 30C & 32C to be placed in the VERTICLE position, when in fact these fillet doors actually rest at a slight angle TOWARDS the Main Landing Gear Door.

I know this is me being my usual Canberra :nerd: however, this info is for those that wish to portray their Canberra realisticly, and as the Group Build is now over, I will be asking the Admins to pin this thread in one of the reference areas of the forum.

Bexy

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