CANBERRA – PR.3 – WF922 – RESTORATION LOG

Having finished the last update on paintwork, and to provide a little bit of continuity (not something I am good at), that’s were I will start.

Painting and Decals

Obviously winter is not ideal for painting but a few very good warm days in January enabled me to put some paint on the topside and the engine cowlings. A stencilling machine was purchased by the museum (after much pleading) which allowed me to re-stencilled the underside that was painted during last year with all of the relevant paint codes and specs.

Cowling and Decals

Wing Attachment Bolts

One of the jobs that I had been looking forward to doing was to finish off the wing re-assembly that was left unfinished all those years ago. Both top and bottom access panels that give access to the main wing attachment points were opened (after some drilling out of screws) to expose the main spar attachment points. Those of you that are familiar with the Canberra will have to bear with me as I explain, but there are two main upper and lower attachment bolts on each side, these are 1″ BSF at the top and 3/4″ BSF at the bottom, seven 5/8″ nuts and bolts in between the two finish off the main spar point. Searching through the museum’s very large accumulated stock provided all but the 1″ BSF nuts that I had to source from outside. Everything was then torqued and split pinned. To round the job off, I riveted on some strip anchor nuts that I made for the access panels mountings, so that they fitted back with all of the screws, after the job was finished.

Next the rear attachments were located and once again a panel had to be drilled out to get at one side of the pin. Access was gained for the other end of the pin by lowering the flaps; there is just a single pin that is easily fitted and I actually found the correct pins that had survived all this time wedged inside a nearby stringer on either side. A repeat process on anchor nuts and the job was finished. In all it took about six working days to complete but I now know that if and when the aircraft is towed around again the loading on the main spar is distributed as the manufacturer intended.

Wing attachment and Seven Bolts

Belly Tank Straps

The belly tank access panels had never been off and, despite copious amount of WD40, the thumb-push fasteners still remained firmly stuck. Now it is not my intention ever to lower the belly tank but it’s nice to be able to pop the fasteners to look at how it is attached and to keep the attachments lubricated. So I had the time during the winter days to get to grips with the panels and eventually all four succumbed to prising and pushing with all manner of incorrect tools but I achieved my aim. Most of the thumb push fasteners were recoverable and each panel was cleaned awaiting re-fitment. Lots of lubrication to the not to badly rusted belly tank straps was applied and new gaskets and screws were fitted to the refuel filler neck before all the panels were re-fitted. Just another of those jobs that no one ever sees.

Belly Tank Strap and Strap Panel

Belly Tank Filler Before : Belly Tank Filler After

Very Pistol

Winter of course saw me searching for useful things to do inside an already restored cockpit (but will it ever be finished?) and I remember the museum’s Curator telling me that they had a (donated) Very Pistol that might fit the Canberra. Well the mounting was already there so I married the two up and just my luck they didn’t fit. It would seem that different aircraft had different pistols, why I don’t know as the cartridges were the same. I took the view that if anything was going to be modified to make it fit it wasn’t going to be the aircraft. After filing down a collar on the pistol and correctly making a locking slot I eventually got the pistol to fit and lock in to the navigator’s hatch mounting correctly. A security chain attached the pistol firmly to the aircraft and, although it was never there in service, I bowed to pressure on security grounds and made it look as authentic as possible. (Click on second photo for larger image.)

Very Pistol and Coupling : Very Pistol In Place

F95 Camera Controller

I had found (on Ebay) an F95 Camera Controller of a type that was fitted to the aircraft during its latter years on PR work. Although the controller might be a slightly more modern version of what was actually used its the best I am able to do. This was positioned by looking at the pictures of Hendon’s PR3 (and with the helpful knowledge of an ex-RAF photographic tradesman) to the stbd side of the cockpit just below the canopy line.

Now, as all evidence of WF922’s previous PR life had been removed, I had to fabricate a bracket to mount the controller. On this scratch-built bracket I had to make and fit a standard photo controller wedge securing bracket. As it required mounting on a double curvature area a lot of care had to be taken to get a good secure fit.

F95 Controller and Mounting : F95 Controller In Place

Canopy Demist System

I had been using a disconnected canopy de-mist pipe to hook my headset on for some time now and it began to look decidedly unprofessional doing it. To remove the temptation, this meant a complete overhaul of the canopy de-mist system would be needed, well it was overdue anyway. Both port and stbd silica gel demist containers were removed along with the round paper filter container behind the pilot’s instrument panel. Both port and stbd containers were, of course, cleaned, re-sprayed and replensihed with new gel crystals and new rubber piping was fitted and secured (with as many small Jubilee clips that I could scrounge). I don’t suppose the silica gel will achieve much but the whole system looks good and it has given the cockpit that distinctive smell of new rubber again.

Canopy Demister : Silica Gel Container

Pilot’s Oxygen Bottle

A start has been made on the (already discharged) emergency oxygen bottles with the pilot’s being removed for cleaning first. One of the things that I noticed was a label giving the date of the last service as March 1975 at the A and AEE. Now if my memory serves me right these were usually replaced every three months, so that would indicate that WF922’s last flight was made between March and May 1975. This is an important find as the ‘last flight’ question is one we have had to fudge previously with an educated guess. Quite a few labels have been found on equipment but nothing as date specific as this with a known service interval. If anyone knows the real service interval of these bottles at about this time then please get in touch. The bottle was re-fitted with a cable to connect to the yellow and black pilot’s pull knob located on the stbd side of the seat and re-fitted to the aircraft.

Pilot’s Oxygen Bottle – Label

Green Satin

Finally for this update the aircraft’s Green Satin transmitter/receiver and tracker units were removed from MAM’s storage to have a look at the insides and to possibly re-fit to the aircraft. By the way, surprisingly, the cans still had some residual pressure in them after some 30 years! After releasing this residual the cans were removed to expose state of the art, circa mid 1950’s, Doppler radar. Everything inside was in pristine condition, not even a layer of dust on the huge valve that had a cautionary 10,000 volts label close by. It had been a thought that we might display these items in some way before re-fitting them and that might still happen given the correct conditions. However, the internal condition has made me have a re-think and until I decide, I have re-greased the seals on the cans, re-fitted and tightened the clamps and re-pressurised them. They are just in too good a condition to allow them to deteriorate in any way at all. There may not be many Green Satin units left in the UK but, probably, none will be in a better condition than these. The navigator’s Green Satin indicator was also removed for a clean up and although in good overall condition hasn’t had the benefit of a sealed container for all of its life.

Two views of the internals of the Green Satin kit . . .
Green Satin Tracker Unit : Green Satin Transmitter/Receiver Unit

Green Satin 1 : Green Satin 2




Green Satin 3 : PTR175 Tray

Photo of the complete Green Satin Doppler in position.

To finish on the radio installation topic, I have obtained a PTR175 mounting tray to fit in the fully repaired and waterproofed (I hope) top hatch, this should enable me to finish off the VHF/UHF radio installation started by Marshalls in 1975/76.

End Up-Date

This report is an up-to-date, in-depth review of restoration progress, which leads to the inevitable question – “When will you finish it?” The answer being “probably never” but as I’m having fun, why should I?

Malcolm Lambert
Midland Air Museum
March 2005

Webmaster says : Sadly although a lot of its systems now work and it looks much better, WF922 will never fly again, not even taxi under power – but this exhibit is definitely worth visiting not only to see one of only two PR.3’s left in the UK, but also just to experience a true, systems-working Canberra.

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