Canberra Air Start

[jedinein]

Anyone familiar with the Canberra Bombers, all versions, and how they were started? I'm looking for technical specs (if available) for how a few Air Forces used air carts to get their Canberra engines going. I see some pictures online of compressed air hoses attached to the breech caps, but no details on what sort of air pressure or fittings were used.

Thanks much for any leads, pointers, or ideas.

[rusty_monkey]

Our last ones used Avpin instead of the 4inch shells. Great joy of pouring avpin into the tank by the engine in the desert. Also all the hassles of not being able to ship the damn stuff anywhere.

The trainer still had carts but the PR9s were all avpin (you got about 12 startsper tank full)
The specs can be found online
and this link may help:

Avpin - Key Publishing Ltd Aviation Forums (http://forum.keypublishing.com/showthread.php?t=94191)

[Lukeafb1]

The B15, B16, B2, B6 and T4 were all started by electrically fired starter cartridges (3 per engine). Not sure about other mks.

[27mm]

E15 - 3 breech starter; PR9 - Avpin (cf Hunter & Lightning)

[MrBernoulli]

Rhodesian Air Force used compressed air starting. Away from home at the moment so can't check for details, but will do so when I return later in the week, unless someone else provides details for you in the meantime!

[Jellybrain]

PR7 was 3 cartridges per breech starter, the TT18 was single shot cartridge like B2, T4, max three attempts.

[Fareastdriver]

Cartridge stars, and also Avpin, was an Air force thing. Most British aircraft exported to other countries had far more sensible ways of starting the engines incorporated in them.

[SirPeterHardingsLovechild]

...and the Triple Breech Starter cartridges (PR7, E15) were 10Mk3

the Single Breech Starter cartridges (B2,T4,TT18) were 9Mk2

How sad am I?

[jedinein]

Thanks much!

I'm dealing with a Canberra with a 3 cartridge system, but the cartridges are rather difficult to come by (and really annoy the local authorities). I would really appreciate any details on the conversions to the air cart or other methods to start.

Or if anyone has leads on where I could locate some cartridges, that would also be appreciated.

[Dengue_Dude]

he Single Breech Starter cartridges (B2,T4,TT18) were 9Mk2

My polished starter cartridge is in my dining room. I used to be the Canberra OCU ground instructor 87 - 90, and I remember each (of the single breech cartridges contained 720 gms of cordite).

We used to have a starter shaft from the engine that had an almost perfect spiral in it. The cartridge had been fired into an engine that had seized and all that energy had just twisted the shaft - a work of art.

I believe the triple-breech starters used the same cartridge but had the three attempts.

PR9 used AVPIN, but not sure about any others that had the system.

They were also highly successful in setting pianos on fire I seem to remember. . .

[SirPeterHardingsLovechild]

Dengue_Dude

I believe the triple-breech starters used the same cartridge but had the three attempts

Actually, they were different. The most obvious being that the Triple Breech Starter cartridge had a disc in the end that depressed a plunger to direct the cordite from the correct breech.

Check the bottom of your cartridge to see what Mk it is (unless you polished the bottom as well.) I'm guessing 9Mk2.

If I've got the 10Mk3/9Mk2 cartridges the right way round, a used 10Mk3 will have this disc rattling around inside, but the 9Mk2 won't.

Back on 13 Sqn, I had the idea of sticking a Sqn zap on the cartridge and then tracing over the graphic with a vibrating etching tool. Mine are in the garage.

I'm interested to hear about other nations using an air start trolley. Presumably it would need a modified breech cap to take (quite a lot of) air pressure/flow. But then you have to remove the device from a running engine!

I had to remove a single breech cap from a running engine while detached at St Mawgan, in order to get the other one going. I wouldn't recommend it.

[retrosgone]

I went through the Canberra OCU at Marham in 1980, and we had a Zimbabwean (formerly Rhodesian Air Force) crew on my course.

Sanctions during the war caused them to make many improvisations to keep their aircraft operational. They could not obtain cartridges, so they used compressed air instead. From the way they described it, this was a lash-up involving a large "bottle" attached somehow to the starter so that the air could spin up the starter turbine in the same way as the cartridge gasses would during a "normal" start. Of course, the connection had to be removed as soon as the engine was running.

Those young guys (Messrs Ludgater and Mew as I recall) had some pretty amazing tales to tell. Never heard how they got on on their return to Mugabe's paradise - - -

[Blacksheep]

this was a lash-up The Rhodesian Air Force had a lot of ex-Halton Brats in their ranks, so there was no need of such a thing as a "lash-up". All improvisations would have been well thought out and designed modifications, beautifully executed by highly skilled technicians. ;)

[Airbrake]

Jellybrain, check your pm's.

Cheers.

[Dengue_Dude]

Hi again, I've learned about 5 aircraft since then so not surprised I'm rusty . . .

The cartridge has a damn great bolt through the bottom and is engraved etc and also has a 231 OCU badge stuck on it. Can't really get at it as it's on a lovely little oak plinth (done in the Carpenter's Shop at Wyton).

But I'm sure you're right.

Off topic really but best of luck to the project. I enjoyed my little bit of flying in the Canberra, especially Wyton-Pratica de Mare-Akrotiri with Dave Pipes and Badger, went back in a Tristar (my next posting then).

Oh, nostalgia

[Rigex]

I remember being on a secret RAF/Navy Sqdn operating highly secret T17s, which were full of amazing secret gubbins which all had mysterious names/nomenclatures which only the "Fairies" (electronics persons) understood - giving them something of an advantage in the "Trade-cred" ratings.:bored: One of the RN A/E (= sooty/rigger in RAF) decided to enhance his/their image. Thus it came to be, that where previously an old carton with "used cartridges" scrawled on it had been, now stood a wooden box with "Expended Propulsion Unit Motivation Initionators" proudly stencilled thereon.:O

[mtoroshanga]

The Rhodesian Air Force used a standard air bottle trolley with a dummy cartridge in the breech. It took a bit longer to spin up but when started the blank was removed and a standard cartridge fitted into the breech. It was certainly no lash up. Away from base the SOP was observed.
As far as I remember use of the air start extended starter life.

[Wander00]

But not the nostalgiia of the, "bang", and the whiff of cordite through the DV window!

[Lukeafb1]

So you were based in Rutland as well, Rigex!

[Rigex]

Yup, was there for the end of the Triangles, then 115 Varsitys / Whistling Wheelbarrows, then the mighty 360th! All that and Ruddles too. . . :ok:

[jedinein]

If y'all want to experience the nostalgia, the Canberra I'm working on is for sale, if you a few million laying around waiting for a good cause.

Thanks for the pointer on the air start.

[FL575]

I seem to remember that when the PR9s RR 206s were sent back to Rolls Royce for servicing, they did not bother with the Avpin starter. It seems they unbolted that from the front of the engine, and replaced it with an electric starter, salvaged from the engine off a Caravelle.

[bvcu]

comet avon was elec start as well , remember canopus and the RAE one regularly tripping modern GPU's when away from base ! believe one lightning T4 had elec start as a trail years ago .

[CBrent]

jedinein (http://www.pprune.org/members/161559-jedinein)



Reference your post on Canberra Air Start discussion - Is the Canberra still for sale and if so please provide details - Where is it, what state is it in, which model etc.

I have been searching for a Canberra to buy for years, either flying or that can restored back to airworthy status so if there is anyone out there that knows of one I would love to hear about it

Many thanks

Craig Brent

[jedinein]

I know where one or two are available. Please email me at eagle3352 at yahoo.com.

[zetec2]

Don't know if this helps taken from a Rhodesian Air Force site:
quote:
Avon Engines in general.
The starting systems of these engines has not been discussed up to this point. The Avon 1 as fitted to the Canberras that we had, used a single breech cartridge starter. When the cartridge was fired, the high velocity gasses went through guide vanes and forced the small turbine to spin at very high speed driving through a reduction gearing to the engine. The engine would rotate up to 1000+ rpm, causing sufficient air flow through the engine to allow fuel and ignition to cause combustion to take place, which achieved slow running speed. This made the A/C self sufficient to operate at any airfield without the use of any ground equipment, eg starting houbart or battery cart as for the Vampire.

The Avon 207 as fitted to our Hunters had a completely different starting system. However the same principle applied in that it was self sufficient, being able to obtain 3 starts at any airfield without ground equipment. The starter was like a small jet engine, which used a fuel called AVPIN. When operated, the scavenge pump blasted air through the starter for 5 seconds, and then fuel and ignition. The starter would explode into life. A heavy blast out the starter exhaust caused a tremendous noise for about 10–12 seconds. The starter turbine reached 33,000 rpm. and with a gear reduction, an engine speed of 1200rpm. was achieved. I can remember, during Hunter starting, with gloves on, putting out flames at the starter exhaust, ensuring all was extinguished before closing the starter bay door. The AVPIN system was a tank situated on the inside top of the fuselage, with a cap for refilling. This was capable of giving 3 starts. A pump would draw Avpin to supply the starter combustion chamber and an electrical control box introduced ignition as well as timing of the starting
cycle.

Compressed Air Starting.
Due to the cost and difficulty in obtaining cartridges for the Avon 1 and also conserving starter life, air starting was desirable to use at home base and cartridges used for away trips. A removable adaptor was fitted to the front of the starter to take the compressed air line nozzle. It took a lot of experimenting and eventually ended up with 4x large air bottles on a trolley, connected via a controllable on/off cock onto one air line to the engine starter. All the bottles were charged to 3000+ psi. which would rotate the engine to about 980 rpm -just enough for light up! About 3x starts could be obtained from a set of bottles.
A recharging facility had to be installed at ERS. This was an industrial type Atlas Copco compressor which did the job of recharging the bottles on trolleys for 5 Sqdn and our own test-bed use.

The Avon 207 air starting presented problems when fitted to the A/C. For test bed use an old starter was used, with the combustion chamber removed and the guide vanes retained. A thick flat plate was manufactured which had a correctly angled pipe welded on with a nozzle attachment for the HP starting air line. With 4 x 3000 psi bottles released, the engine would turn over at 900+ rpm, enough for light up. A set of bottles would achieve 2x good starts. This system did very well for our ERS and test bed requirements, as well as for doing a starting run for inhibiting engines with thin oil. But fitting it to the Hunter was another story. It could be fitted with the flat plate system (as per test bed) but then there would be no Avpin system. It was tried of cause and worked well with the HP air line coming out through the starter bay. There were many unsuccessful attempts at adapting the Avon 207 starter combustion chamber to
take the HP air connection as well as using the normal Avpin starting system. For this reason, the A/C had to remain with the Avpin starting system. Having to have air starting bottles away from base would not make the A/C self sufficient. It seemed the avpin was somehow obtainable, but the spares for the starter, ie the turbines and bearings etc, were difficult to obtain.

unquote.
Paul H.

[Q-RTF-X]

Thus it came to be, that where previously an old carton with "used cartridges" scrawled on it

Hummmmmmmmmm. Correct term should have been "Fired Brass" I seem to remember :oh: