Canada and Australia: what would you build?

[Shortround6]

Correct. De Havilland Australia built 1070 DH 82 Tiger Moths, 87 DH 84 Dragons, 8 DHA G1's & G2's and 212 DH 98 Mosquitoes.

Those are very commendable totals but according to Wiki;
"Additional overseas manufacturing activity also occurred, most of which took place during wartime. de Havilland Australia assembled an initial batch of 20 aircraft from parts sent from the United Kingdom prior to embarking on a major production campaign of their own of the DH.82A, which resulted in a total of 1,070 Tiger Moths being constructed locally in Australia.[17] In late 1940, the first Australian-assembled Tiger Moth conducted ins first flight at Bankstown, Sydney"

Bolding by me. Wiki may be wrong and obviously DH of Australia had a hand in assembling or erecting DH aircraft sent from England in the 30s, I doubt they were shipped fully assembled. But actual manufacturing capability of of the Australian DH organization in the 1930s was minimal.
It is all very well to talk about building 4 engine bombers in Australia in 1940 but when the extent of the local industry is building a few Wirraways a month and assembling Tiger Moths from parts kits sent from England the practicality of the situation is far different.

What the Australians accomplished in 1942-45 is far different, but you have to walk before you can run.

 

[Graeme]

Tiger Moth production in Australia - trivia....

According to one author - de Havilland supplied the blueprints/drawings/specifications for the Gipsy Major in metric. It took 42,000 calculations to convert them to imperial.

 

[Graeme]

it may be quite possible to fly a Hurricane with NO covering on the rear fuselage (although high drag).
.

I saw this yesterday - a semi-naked Tiger Moth crop-duster. Linen removed to reduce corrosion problems.

Note the rego.

 

[RCAFson]

In the early years of WW2 Canada built 17 Blackburn Shark IIIs. I would have added a couple of zeros to the order, as these aircraft would have been very useful for ASW, Recon and ASR and for flight training.

 

[rednev]

Tiger Moth production in Australia - trivia....

According to one author - de Havilland supplied the blueprints/drawings/specifications for the Gipsy Major in metric. It took 42,000 calculations to convert them to imperial.

england used imperial measurements why would the drawings be in metric ?

 

[swampyankee]

england used imperial measurements why would the drawings be in metric ?

This sounds very much like an urban legend. Dehavilland may have worked in metric, but if the drawings were in metric, it may have been both cheaper and less error-prone to get metric tooling.

As an aside, the US and Commonwealth used different drawing standards, so it was non-trivial to get Imperial-unit Merlins built in the Imperial-unit United States. Add in that the US inch was not the same as the Commonwealth inch, getting P&WA Wasps built under license in Australia or British 6# anti-tank guns in the US was probably more challenging than it first looked.

 

[Graeme]

This sounds very much like an urban legend.

Could be - here's how it appeared in print...

 

[ChrisMcD]

england used imperial measurements why would the drawings be in metric ?

The answer it that the Gypsy engine was created when Frank Halford sawed a WWI Renault V8 in half and then turned it upside down. He did it to use up the huge stock of Renault engines that were being sold off cheap in the 20's.

So if you start with half a French engine you might as well keep it metric!

de Havilland Gipsy - Wikipedia

That's Frank Halford for you. Why be straightforward when you can add extra complexity.

After all this is the man who thought 24 cylinders was a good idea for 1,000 hp. The Dagger deafened aircrews and drove mechanics mad - fancy changing 48 plugs?

Napier Dagger - Wikipedia

 

[swampyankee]

Could be - here's how it appeared in print...

View attachment 365977

Well, some urban legends are true
Overall, it may well have been cheaper and easier for the licensees in Australia to buy metric tooling and gauges.

 

[yulzari]

The answer it that the Gypsy engine was created when Frank Halford sawed a WWI Renault V8 in half and then turned it upside down. He did it to use up the huge stock of Renault engines that were being sold off cheap in the 20's.

So if you start with half a French engine you might as well keep it metric!

de Havilland Gipsy - Wikipedia

That's Frank Halford for you. Why be straightforward when you can add extra complexity.

After all this is the man who thought 24 cylinders was a good idea for 1,000 hp. The Dagger deafened aircrews and drove mechanics mad - fancy changing 48 plugs?

Napier Dagger - Wikipedia

Re Gipsy. The Renault drawings would have been metric. Perhaps De Havilland took the metric tooling route? UK Gipsy mechanics may illuminate the question?

Re the Dagger. Halford's reasoning. Simplified. Is that doubling the power comes from doubling the capacity or doubling the speed. To quote from the late great Keith Duckworth: 'power is the size of the bang times the number of bangs per minute'. The smaller cylinders should have reduced the stresses of high speed running and made the combustion better as well. It worked well enough to dive bomb Calais in 1940 but the failure was in Napier not getting the cooling ducting right and concentrating on stuffing as much air as possible into it rather than getting as much hot air as possible out of it. De Havilland showed the way with reverse flow cooling for their air cooled Gipsy 12s which were heavy for the power.

 

[Shortround6]

Sometimes the complication was needed and sometimes it wasn't. The earlier Rapier being a case point. 340hp from 16 cylinders and 720lbs of engine weight was hardly state of the art in the early 30s.
And Daggers being used in Hawker Hectors to dive bomb Calais in 1940 is more desperation than indication of ability.
The Dagger powered Hectors would have achieved just as much (or as little) if they had been powered by Bristol Mercury's.

 

[ChrisMcD]

Re the Dagger. Halford's reasoning. Simplified. Is that doubling the power comes from doubling the capacity or doubling the speed. To quote from the late great Keith Duckworth: 'power is the size of the bang times the number of bangs per minute'. The smaller cylinders should have reduced the stresses of high speed running and made the combustion better as well. It worked well enough to dive bomb Calais in 1940 but the failure was in Napier not getting the cooling ducting right and concentrating on stuffing as much air as possible into it rather than getting as much hot air as possible out of it. De Havilland showed the way with reverse flow cooling for their air cooled Gipsy 12s which were heavy for the power.

I agree completely. In all fairness to Halford - who at least was not afraid to try and turn theory into practice - there was a cunning plan. According to Setright (The Power to Fly Pg 130)

"Napier and Halford set about the design and production of the Dagger, as a scaled up Rapier but much more refined, larger and with more cylinders. The idea was that this should start out producing at least 1000 h.p. (it was developed to give 1500 on the bench, though it is not believed to have flown in this form) and to power a tiny and very highly streamlined
fighter aircraft whose fuselage would be no bigger than the body of a single-seater racing car of the period. This was why it was air cooled, for there was simply no room for a liquid-cooled system's plumbing, and this was why the built-in ducting for the cooling
 was so exquisitely perfected, for drag had to be minimized by all possible means. It was an attractive project, but an unsuccessful one: for the function of the fighter was beginning to change, and the new heavier generation of single-seaters could afford to carry more weight and bulk. it never was kept in the style to which it should have become accustomed: some scavenging busybody with no mechanical sympathy earmarked it for bomber service, for which it was never intended and for which it was not unnaturally never successful"

 

[swampyankee]

r power is proportional to piston area for engines of a give technological level, and weight is proportional to displacement, so increasing the number of cylinders should give a lighter engine for a given output. Whether it does depends on details of the design.

Napier, however, did not seem to have its engineering act together, with too little attention paid to production cost, serviceability, off-design operation, and broad application. If they were targeting the lightweight fighter market, they should have noticed its non-existence.

 

[Shortround6]

r power is proportional to piston area for engines of a give technological level, and weight is proportional to displacement, so increasing the number of cylinders should give a lighter engine for a given output. Whether it does depends on details of the design.

This seems wrong? can you give examples?
Going the opposite way the Rapier weighed a bit over 700lbs for all but the MK I version and this was for 589 cu in (8.55 ) liter engine.
I believe Weight is proportional to displacement IF similar arrangements of cylinders are made. Comparing radials to inlines gives an advantage to the Radial. 6 cylinder inlines don't show up well against V-8s due to the longer block and crankshaft. The Napier Lion was lighter than some equivalent V-12s due to the shorter blocks/ crankshaft. The Napier engines (Rapier, Dagger and Sabre) all used two crankshafts which added to the weight over an equivalent displacement V-8-V-12 or even inline 6.

Napier, however, did not seem to have its engineering act together, with too little attention paid to production cost, serviceability, off-design operation, and broad application. If they were targeting the lightweight fighter market, they should have noticed its non-existence.

The Rapier may have been intended for the light fighter market with the DH 77 but it is a bit harder to swallow the Dagger. The engine went around 1300lbs for the MK I and just got heavier. Granted it had no liquid cooling system but it was about 45 in tall and had only slightly less frontal area than a Merlin. The weight of the Dagger is heavier than the equivalent year Wright Cyclone 9, several hundred pounds heavier than the Bristol Mercury, 300lbs heavier than a Kestrel and 200lbs heavier than a Peregrine which should take care of the cooling system pretty well.
In the international Market the Dagger was about 200lbs heavier than the air cooled Isotta-Fraschini Delta of 1630 cu in (26.7 liters)
and while the Delta ran much slower it's bigger cylinders (bangs) pretty much made up for the Delta's lower RPM. Plug changes and valve adjustment on the Delta would take about 1/2 the time as the Dagger even assuming equal accessibility.

 

[swampyankee]

This seems wrong? can you give examples?
Going the opposite way the Rapier weighed a bit over 700lbs for all but the MK I version and this was for 589 cu in (8.55 ) liter engine.
I believe Weight is proportional to displacement IF similar arrangements of cylinders are made. Comparing radials to inlines gives an advantage to the Radial. 6 cylinder inlines don't show up well against V-8s due to the longer block and crankshaft. The Napier Lion was lighter than some equivalent V-12s due to the shorter blocks/ crankshaft. The Napier engines (Rapier, Dagger and Sabre) all used two crankshafts which added to the weight over an equivalent displacement V-8-V-12 or even inline 6.



The Rapier may have been intended for the light fighter market with the DH 77 but it is a bit harder to swallow the Dagger. The engine went around 1300lbs for the MK I and just got heavier. Granted it had no liquid cooling system but it was about 45 in tall and had only slightly less frontal area than a Merlin. The weight of the Dagger is heavier than the equivalent year Wright Cyclone 9, several hundred pounds heavier than the Bristol Mercury, 300lbs heavier than a Kestrel and 200lbs heavier than a Peregrine which should take care of the cooling system pretty well.
In the international Market the Dagger was about 200lbs heavier than the air cooled Isotta-Fraschini Delta of 1630 cu in (26.7 liters)
and while the Delta ran much slower it's bigger cylinders (bangs) pretty much made up for the Delta's lower RPM. Plug changes and valve adjustment on the Delta would take about 1/2 the time as the Dagger even assuming equal accessibility.

I was generalizing regarding weight.

 

[ChrisMcD]

Hi Gents, The Martin Baker MB2 rather shows that you are right, the Dagger just did not deliver.

Martin-Baker MB 2 - Wikipedia

And I rather think Frank Halford agreed with you - hence the Sabre!

 

[Shortround6]

I would be very interested in seeing any details of the "light" fighter the Dagger was supposed to go in because the MB 2 sure wasn't it.
Spitfire Prototype..............5332 lb
MB 2 Prototype.................5537 lb
Spitfire MK I 2 Bld prop.....5819 lb

First flight of the MB 2 may have been 4 years after the the Dagger was first run let alone design work started.

 

[MiTasol]

Could be - here's how it appeared in print...

View attachment 365977

I only just found this thread by accident and will comment in a while on some older posts

Ah, Graeme, aint that typically Australian.

Having worked on Gypsy Major engines I do know that the Australian nuts, bolts and studs are all metric exactly like the British built parts of the same part number.

Only an Australian company would waste time converting the measurements (probably using 64ths of an inch rather than decimals) instead of simply training the production staff to use metric micrometres, etc -- or giving them simple go-nogo gauges.

Then again Australia still has Whitworth as a formal primary thread system even though the Brits declared it obsolete for new design in November 1946 and replaced it with Unified. The last mass produced British products to use Whitworth were very early 1950's cars.

Australia still produces and uses Whitworth.

Australia's latest version of metric recently introduced the 13mm bolt and if google is right no other country uses a 13mm bolt. Not surprisingly the 13mm bolt is actually a 1/2 Whitworth bolt renamed to pretend it is metric.

Mi

 

[MiTasol]

Bollocks to no engine production or aluminium smetlting


The Story of the Commonwealth Aircraft Corporation From "Technology in Australia (1788 - 1988)"

It arose from the initiative of Essington Lewis, who was at the time the Chief General Manager of BHP, and who formed a syndicate of BHP, Broken Hill Associated Smelters and G.M.H. to undertake a study leading to the establishment of military aircraft and engine manufacturing facilities in Australia. These companies were later joined by I.C.I., Electrolytic Zinc (for aluminium smelting, set up and in production by 1941) and Orient Steam Navigation Company.

The nucleus of the newly formed company was provided by L. J. Wackett's team, operating at the Tugan Aircraft premises in Sydney. This company was taken over by CAC and Wackett became its first manager. A factory was constructed at Fishermen's Bend in Melbourne and Wackett began to operate from the new premises in September, 1937. In order to enable rapid local production, a licenced design was adopted, both for the airframe (the North American NA33, later known as the Wirraway), and for the engine (Pratt and Whitney Single Wasp. These were being received from 1939, rated at 650 hp).

The innovations needed to put this aircraft into, and maintain in production, consisted of the replacement of the unobtainable British engine, the Taurus, with the locally produced twin-row Wasp engines. This was the main reason why the two stage Wasp was built (locally) ….to get the Beauforts operational. The first locally built, locally engined Beauforts rolled off the lines in October 1941. Local sources of supply had to be arranged for many sub-components (for example the airframes depended on locally smelted and worked aluminium, specifically set up for that purpose in 1940 which were originally to be imported).

Right on Parsifal

Essington Lewis is a much underrated person in this history. Much of the glory for CAC goes to Wackett but it was Lewis who led and financed the world wide search for what aircraft and engines were to be produced by CAC (more below on that search in the last four paragraphs). The whole team, Lewis, Wackett and a group of RAAF officers was lead and financed by Lewis.

One of the many things that Lewis and Wackett contracted prior to the outbreak of war in 1939 was the manufacture by CAC of Lockheed Hudson powerplants, complete except for propellers.

While insignificant in the short term this contract was to not only save the Australian Beaufort program but to also provide the powerplant for the Boomerang. The first 52 Australian Beaufort's actually used Hudson powerplants bolted to an adaptor structure which attached to the same wing fittings as the normal Taurus powerplant. Number 53 and subsequent were fitted with Australian designed mounts and Australian designed cowls and gills though these, like the earlier ones, used the same adaptor structure.
The Boomerang used the Australian Beaufort powerplant with minimal changes other than the mount which was technically a mixture of Wirraway and Hudson.

The British government fought bitterly to prevent the Wirraway being produced and suggested CAC assemble Tiger Moths, then build Tiger Moths, then build other obsolescent designs such as the Fairey Battle.

One major "ace" the Brits had in their pocket was that the Australian Government had to pay import duties to the UK government for any non British aircraft and components.

This resulted in many Wirraway parts being redesigned unnecessarily to avoid the import duty (by maximising "British" content), the installation of Vickers Mk V machine guns rather than the Browning's that even the RAF admitted were a far superior weapon, plus the installation of British radios, gunsights, bomb-shackles etc, etc. The Hamilton Standard prop was replaced by the dH propeller which was nothing more than the HS built under licence by dH but did make it duty free.

Much of the redesign was what could best be called cosmetic - the CA-1 hydraulic shelf for instance is almost identical to the BC-1 shelf except for the width and the changes that causes. Many castings are identical except they use British specification materials, some skins and frames are identical except for using British specification alloy, every non special bolt is the standard SBAC British specification, etc.

It is also highly probably that the British Governments decision to ask the Australian Government to create DAP and produce 90 Beaufort's for RAF Singapore was purely a face saving exercise coming as it did so soon after Lewis and his team decided to manufacture the Wirraway (even without an official order).

The remaining Essington Lewis papers are held by Australian Archives, probably still in Melbourne. I spent some time in the mid 80's scouring the index of Lewis papers in Melbourne and found many gems there however all the Lewis papers (other than indexes) were still classified at that time. Two, of many, that caught my interest were approximately titled Japanese aircraft under consideration for manufacture in Australia and Negotiations with Sumitomo metals for the licensed manufacture of aircraft aluminium in Australia.

Naturally I applied for access to these two documents (the limit for requests at that time) and the very helpful Archives staff assisted me in raising the relevant documentation to ensure the greatest possible chance to have these two files declassified.

Several months later I received a letter informing me that those documents had been sent to the RAAF at Russell Offices in Canberra, that they had been lost, and that I could appeal to have the documents traced. When I discussed this with the Archives staff their first question was Could the contents of these files embarrass the RAAF. When I replied to the effect Very much so because this would likely prove that the Japanese had advanced aircraft and that this was known to Lewis and Wackett and the RAAF officers on his team long before Pearl Harbor. The immediate response from the archives staff was that there was no sense in appealing because the RAAF always destroyed any classified document that could possibly embarrass them.

Needless to say I did not request the declassification of any other Lewis papers.

Mi

CONTINUED

 

[MiTasol]

Once the Pacific war broke out it seems that all British constraints on CAC, DAP, GMH and other Australian manufacturers were thrown out the door.

CAC and the RAAF started fitting many American components to the Wirraway and Boomerang, DAP started some severe modification to the Beaufort such as the big fin to fix the directional stability, flush riveting the wings, ditching the nose turret, adding nose guns, adding up to 3 waist guns, replacing the single wing mounted 303 with a 50cal in each wing, the far better (and earlier designed) Blenhiem turret fitted with two continuous feed Brownings (the Beaufort turret had a single Vickers gas operated with drum feed - supposedly the attacking Jap was supposed to stop his attack while you changed drums), etc.

GMH did considerable redesign of individual parts on several aircraft, starting with the Beaufort engine mount, cowls and cowl gills. On the Beaufighter they redesigned the gear doors using American production practices (which for possibly political, or just plain PR reasons, they called automotive practices).

The picture will not attach so I will try later