Author Topic: A Canadian Raven in Spain  (Read 496 times)

Offline apophenia

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A Canadian Raven in Spain
« on: July 09, 2021, 07:26:41 AM »
As Our Glorious Leader reminds us, the Spanish Civil War falls within the timeframe of this Group Build  :smiley:
___________________________________________________________________

¡No pasarán! ... With a Little Help from Fort William, ON

Okay ... this concept spawned a backstory which just kept growing! Eleven paragraphs into the story and I was still on the initial Canadian political changes and it was showing no signs of stopping

So, I've knocked that on the head! Suffice to say, After the ousting/'sectioning' of William Lyon Mackenzie King in September 1937, a National Restoration Government was formed as an uneasy coalition of the three major parties in Parliament. For reasons of complex internal political manoeuvring, the Government of Canada reversed its position on arms exports to Republican Spain. As of 01 January 1938, approved 'military' exports from Canada to the Republicans would be allowed.

Canada was also experiencing a mushrooming of aircraft manufacturing divisions of the nation's existing heavy industry firms. Few of these corporations had the least notion of how to build aircraft but one of the least plausible was judged to be Canadian Car & Foundry (CCF or 'Can-Car'). Can-Car had dabbled in both shipbuilding and armaments production during WWI. Several minesweepers intended for the French sunk on sea trials. A New Jersey munition factory simply disappeared in a massive explosion. This time around, the Canadian Car & Foundry board of directors were following the money but had made no attempt to consult with the RCAF, DND, or the Federal government at large. For these, and other reasons, Ottawa preferred that Can-Car stick to building rolling stock and producing steel fittings.

During WWI, Can-Car had been given control of a new factory paid for by the citizens of Fort William, ON. At the end of 1937, the newly-formed Ministry of Armaments Production stepped in. As it happened, the Minister was CD Howe - Liberal MP for the local riding of Port Arthur. Aware that Can-Car had ignored the terms of its contract with the people of Fort William, MAP took control of the factory space and transformed Can-Car's aircraft division into a Crown Corporation - Canadian Aircraft Industries, Ltd (CAIL, or 'Can-Air' as it became known). [1] Can-Air took over all of Can-Car's extant Fort William aviation projects. [2]

Can-Air C-24 Corbeau - A Canadian Raven from Fort William

Can-Car had negotiated with aircraft-maker Grumman to license-build that US firm's obsolete G-23 fighter. As the GE-23, a prototype had been assembled from US components. However, there was little interest in this warmed-over biplane. Having anticipated this, Can-Car's Chief Aircraft Engineer Elsie MacGill had redesigned the airframe to accept a monoplane wing of her own design. [3] This aircraft - the Can-Car C-23M had just completed its flight-testing when MAP took over control. As this first of two C-23Ms was being put through it paces, new all-metal wings were being constructed to mate with supplied G-23 fuselages. These assemblages would emerge as the new Can-Air C-24E Corbeau (Raven) monoplane attack aircraft.

Bottom Canadian Car & Foundry C-23M prototype at Fort William, ON, prior to its trials at RCAF Rockcliffe.

The C-24 Corbeau was produced mainly as a skill-building exercise for Fort William workers and design staff. The RCAF had reviewed the Can-Car C-23M at Rockcliffe and foresaw no role for this aircraft type. As such, the C-24E was produced exclusively for a potential export market. Interest in the C-24E had soon come from the Second Spanish Republic. [4] With exports to Spain during its civil war no longer prohibited, orders were quickly signed. The Spanish contracts included three aircraft types. These included: the sole GE-23 biplane (known locally as the Delfin) which was to act as a crew trainer; both C-23M wooden-wing prototypes as advanced trainers; and 40 x C-24E attack aircraft - locally dubbed Cuervo (the Spanish for raven).

Top Can-Air C-24E Cuervo (Raven), Arma de Aviación, while working up in Barcelona prior to deployment to the Ebro Front in southern Aragon, Summer 1938. An anti-glare panel has been applied in Soviet A-24 Camouflage Green (although paint adhesion seems to be a problem). The C-24Es were delivered with tricolour roundels on their wings but these have been overpainted with full-chord red recognition panels.

The emblem of the 2ª Escuadrilla has been painted over the Can-Air logo on the fin. The slogan ¡Esta máquina mata a los fascistas! (This machine kills fascists!) appears below the cockpits - possibly indicating an American Brigadas Internacionales crew. Note that the observer's Darne machine gun in fully deployed.

Several differences can be seen between the C-23M prototypes and the production-type C-24E. The latter features a long-chord NACA cowling; greater dihedral on its metal-framed wings; a strengthened tailplane (dispensing with the bracing strut from the Grumman design); a slightly enlarged rudder; and a simplified tailwheel. For its Cuervos, the Spanish Republic also stipulated that the rear cockpit enclosure be simplified - in order to speed deployment of the flexible armament.

______________________________

[1] The Courts had returned ownership of the actual factory space to the citizens of Fort William but Can-Air negotiated a 10-year lease on the property subject to enforceable local employment conditions. Can-Car chose not to seek compensation since the Courts had made clear that Fort William council was free to seek reimbursement for Can-Car's 1921-1936 breach of contract with the city.

[2] Canadian Car & Foundry retained the right to 'sell on' rejected aviation projects - such as the purchased Wallace 'Touroplane' (aka Maple Leaf I) as well as designs for the unbuilt Maple Leaf II trainer and R-500 radial engine. Contracts with American designers Vincent Burnelli and Michael Gregor were allowed to lapse.

[3] As with her earlier Maple Leaf II trainer design, this wing was a fabric-covered structure primarily made of wood but with aluminum ribs. For production aircraft, the fabric-covered wing structure would be entirely of metal. The initial plan for surplus G-23 wing sets was that they were to be incorporated into a new biplane trainer design.

[4] Depending on source, this 'E' suffix is listed as standing either for 'Export' or for 'España'.
"She always found it peculiar to encounter a time she had actually lived through rendered as a period." William Gibson, Zero History

Offline Buzzbomb

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Re: A Canadian Raven in Spain
« Reply #1 on: July 15, 2021, 02:11:35 PM »
Ole !
Different look. The markings look quite natural for that era

Re: A Canadian Raven in Spain
« Reply #2 on: July 16, 2021, 02:09:56 AM »
Maybe Canada also stared building aircraft engines. Perhaps some copies of Bristol Mercurys and Pegasus engines.



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Re: A Canadian Raven in Spain
« Reply #3 on: July 16, 2021, 03:29:34 AM »
Maybe Canada also stared building aircraft engines. Perhaps some copies of Bristol Mercurys and Pegasus engines.


Well, the Canadian Pratt & Whitney Aircraft Company, Ltd. was founded in November 1928 to act as a service centre for P&W aircraft engines and during World War II, it assembled Pratt & Whitney Wasp series engines built in the U.S. so it isn't inconceivable.
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Offline robunos

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Re: A Canadian Raven in Spain
« Reply #4 on: July 16, 2021, 03:44:33 AM »
Maybe Canada also stared building aircraft engines. Perhaps some copies of Bristol Mercurys and Pegasus engines.



Chris


If this happened, it would enable Bristol in the UK to switch over entirely to sleeve valve engines, maybe even get the Centaurus into service before the war ends . . .


cheers,
Robin.
By the pricking of my thumbs, Something Whiff-y this way comes . . .

Offline apophenia

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Re: A Canadian Raven in Spain
« Reply #5 on: July 16, 2021, 08:34:19 AM »
Thanks folks!

Maybe Canada also stared building aircraft engines. Perhaps some copies of Bristol Mercurys and Pegasus engines.

I think that idea has legs Chris. A 'Bristol Engines (Canada)' could supply the RCAF's needs with surplus exported to the UK. For the RCAF, there'd be (Mercurys for the Bolingbrokes and Lysander IIIAs and Pegasus for the Stranraers and Hampdens. Lots of BCATP Battles also received Cyclone engine-swaps - could've been Pegasus instead.

Well, the Canadian Pratt & Whitney Aircraft Company, Ltd. was founded in November 1928 to act as a service centre for P&W aircraft engines and during World War II, it assembled Pratt & Whitney Wasp series engines built in the U.S. so it isn't inconceivable.

Too true. Canadian Wright Ltd was set up in Montreal in 1926 (IIRC) but didn't get a full license of Wright engines until 1928. Too late! IIRC, the first Wasps in Canada were assembled by  Canadian Wright. That must have been galling!  Canadian Wright's big comeback was supposed to be the Norseman - but only the first five got Whirlwinds - and most of those were later converted to Wasps.

In 1948, Canadian Wright was swallowed by the improbably-name Mailman Corp. (A.L. Mailman, Pres.), some kind of holding company that gobbled up under-capitalized firms (Ottawa Car & Aircraft being another of their 1948 puchases).
-- https://img6.newspapers.com/clip/45085221/national-post/

One wartime firm that puzzles me is British Aeroplane Engines Limited. I'm not sure when they were established but, at some point, they were owned by Rotol, Rolls-Royce, and Bristol (if I understood rightly). During WW2, British Aeroplane Engines shared facilities with Canadian Wright Ltd. in Montreal. Don't know what the deal was there ... but the two firms also shared a poster campaign ("Daddy Helps Build Them") which featured a stylized Bolingbroke ... so, Mercury-powered if that's significant.

If this happened, it would enable Bristol in the UK to switch over entirely to sleeve valve engines, maybe even get the Centaurus into service before the war ends . . .

Good point. If production of the Mercury and Pegasus was shifted to Canada early enough (say, 1937), perhaps Bristol would have been less distracted/overloaded?  It probably wouldn't have sped up progress on the Hercules much but it is fun to speculate on a Taurus-powered Blenheim  :smiley:
"She always found it peculiar to encounter a time she had actually lived through rendered as a period." William Gibson, Zero History

Offline jcf

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Re: A Canadian Raven in Spain
« Reply #6 on: July 16, 2021, 09:49:55 AM »
How about a plan-view showing the new wing design?

 ;)
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Offline apophenia

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Re: A Canadian Raven in Spain
« Reply #7 on: July 17, 2021, 10:55:27 AM »
How about a plan-view showing the new wing design?

As requested, the planform of the CCF C-23M and Can-Air C-24 Corbeau/Cuervo showing their 'Hershey-Bar' wings.

This plan view is split into two - the right half being the CCF C-23M, the left half representing the Can-Air C-24E.

Right side Canadian Car & Foundry C-23M second prototype (c/n 23-2-02) in service with the Arma de Aviación. Scheme is overall silver dope with a locally-applied anti-glare panel (Soviet A-24). Delivered with Republican roundels on its wings, this aircraft's rondas have been over-painted with broad red ID panels.

Right, scrap view Starboard wing of the CCF C-23M first prototype (c/n 23-2-01). Detail differences are faired-in wingtip navigation lights (which were carried over to the production C-24) and an underwing pitot tube (which was distinct to this first prototype).

Left side Production Can-Air C-24E-1 Cuervo (Raven) of the Arma de Aviación. Scheme is as per the C-23M with aluminized paint substituted for dope on the metal-skinned wings. Note the longer-chord cowling and revised fully-cantilever elevators.

Left, scrap view Portside wing of the sole Can-Air C-24E-2 Cuervo. This aircraft had an additional pair of wing guns ... but this came at the cost of slightly reduced fuel tanks. The added weight of the guns and their ammunition also reduced the potential bomb load (especially in hotter weather).

The C-24E-2 was the first of a second batch of Cuervos. These twenty aircraft came with red ID panels already applied. The second batch also differed slightly in their internal fittings from the first batch.

In Spanish service, the C-24E were sometimes identified as ACs (for Ataque Cuervo) in the same way that the biplane C-23s were ADs (Ataque Delfíns)


"She always found it peculiar to encounter a time she had actually lived through rendered as a period." William Gibson, Zero History

Offline jcf

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Re: A Canadian Raven in Spain
« Reply #8 on: July 18, 2021, 03:53:35 AM »
Thanks.  :smiley: :icon_fsm:

I have one of these, you see.
 ;D

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Offline jcf

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Re: A Canadian Raven in Spain
« Reply #9 on: July 18, 2021, 04:09:30 AM »
Perhaps an engine change, R-1535 power like the XSF-2 or P & W Wasp like the GG-1 demonstrator?


XSF-2


GG-1, re-engined with an R-1820, went to CC & F and was lost at sea off the coast of Costa Rica on
29 Sept. 1937 while on a demonstration tour.
“Conspiracy theory’s got to be simple.
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Offline apophenia

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Re: A Canadian Raven in Spain
« Reply #10 on: July 18, 2021, 10:38:47 AM »
I have one of these, you see.

Oh very cool  :smiley:  My 'Hershey Bar' wings are a little unimaginative but I thought anything more adventurous would be a stretch for Elsie MacGill at that stage. But for modelling, I'm at a loss for potential wing 'donor' candidates  :-[

Perhaps an engine change, R-1535 power like the XSF-2 or P & W Wasp like the GG-1 demonstrator?

Oh yeah! That really changes the look  :smiley:

An F2F would be the obvious cowling/engine 'donor'. I see that there is an Arma F2F-1 kit available in 1/48 ... but it is wildly expensive! The Accurate Miniatures Gulfhawk II isn't all that cheap either.

A glance at Scalemates doesn't reveal any aftermarket options for F2Fs  :(

The RW Gregor FDB-1 had a Pratt & Whitney R-1535-72 (maybe in whif-world that engine was ordered before decision to let Gregor's contract lapse?). The FDB-1 had a smooth cowling which broadens the 'donor' range a bit.

BTW: I'm intrigued by the canopy arrangement on that GG-1.

Another engine option mentioned was going British - a Mercury making sense to me. A simpler engine-change option (for Republican aircraft anyway) would the Soviet M-25. Engines & Things makes an M-25 (although it probably looks much like your kit's Cyclone). Airwaves does a 'correction set' for the I-16 type 5 which includes the cowling - an expensive option but any Airwaves set buyer will have a spare Hobbycraft cowling lying about  ;D
"She always found it peculiar to encounter a time she had actually lived through rendered as a period." William Gibson, Zero History

Offline robunos

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Re: A Canadian Raven in Spain
« Reply #11 on: July 18, 2021, 05:16:22 PM »
When I built my OWB Grumman Duck, I used Polikarpov R-5 top wings . . .   ;)


cheers,
Robin.
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Offline jcf

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Re: A Canadian Raven in Spain
« Reply #12 on: July 19, 2021, 02:57:08 AM »
A few of the Accurate Miniature F3F-1, R-1535, are on ebay but prices aren't great,
and on some the shipping is ridiculous. Yeah, costs have gone up but what some of
them want for domestic US shipping is ridiculous.
 >:(
“Conspiracy theory’s got to be simple.
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Offline apophenia

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Re: A Canadian Raven in Spain
« Reply #13 on: July 19, 2021, 11:02:03 AM »
When I built my OWB Grumman Duck, I used Polikarpov R-5 top wings . . .

And that's a big wing! Cheers Robin, that would probably work a treat for the 'rag-wing' C-23M variant  :smiley:

A few of the Accurate Miniature F3F-1, R-1535, are on ebay but prices aren't great, and on some the shipping is ridiculous. Yeah, costs have gone up but what some of them want for domestic US shipping is ridiculous.
 >:(

Yep, gouging seems to be the order of the day  :P  A pity, ... that R-1535 really does change FiFi's looks.
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Offline jcf

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Re: A Canadian Raven in Spain
« Reply #14 on: July 21, 2021, 03:21:26 AM »
What are the dimensions on the new wing? Yeah, I know I could scale it off
the plan-view, but I'm feeling lazy.
 ;) :icon_fsm:
“Conspiracy theory’s got to be simple.
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Offline apophenia

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Re: A Canadian Raven in Spain
« Reply #15 on: July 22, 2021, 07:31:05 AM »
What are the dimensions on the new wing? ...

Errm, not as lazy as me! I reckoned bigger than the original upper wings = good enough   :-[

So, ... scaling off my plan view, we know that the original FF-1 fuselage length was 7.47 m (24.5 ft). From that, my  very rough guesstimation would be a C-23M/C-24 wingspan of around 11.25 m with a chord of ~ 2.25 m.

I know, that sounds like a really small wing but the FF-1 fuselage was a bit of tiddler too.
"She always found it peculiar to encounter a time she had actually lived through rendered as a period." William Gibson, Zero History

Offline jcf

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Re: A Canadian Raven in Spain
« Reply #16 on: July 23, 2021, 01:32:04 AM »
 :smiley:

“Conspiracy theory’s got to be simple.
Sense doesn’t come into it. People are
more scared of how complicated shit
actually is than they ever are about
whatever’s supposed to be behind the
conspiracy.”
-The Peripheral, William Gibson 2014

Re: A Canadian Raven in Spain
« Reply #17 on: July 28, 2021, 10:13:58 AM »
Another thought! If Canada got into Mercury & Pegasus production early enough, maybe they might have also looked at the possibility of twin-row offshoots. The Mercury cylinder putout about 93.3 hp. So, if you were to build a two-row 14 cylinder engine, you could have an engine with a slightly smaller diameter than a Mercury, putting out about 1300 hp. Tweak that a bit and use some high grade fuel and you might get 1400 hp. Throw a couple of those onto a Blenheim or a Beaufort, then you've got something. Add one to your Raven, you'll have quite the fighter!



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with a uniform to wear,
a fast aeroplane to fly,
and something to shoot at?"

Offline apophenia

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Re: A Canadian Raven in Spain
« Reply #18 on: July 29, 2021, 06:31:39 AM »
All good points Chris. Having previously posited a 'Bristol Engines (Canada)', I am now thinking that some variation on the RW British Aeroplane Engines Limited would be more productive.

Being separate from Bristol Aero-Engines Limited would free-up the firm from Roy Fedden's obsession with sleeve valves. (Licensing the Mercury allows you to do as you will with that design.) So, instead of Hercules, a Canadian-controlled British Aeroplane Engines could be developing your 'Double-Mercury'.

Outputs would be equivalent to early-model Hercules but would be using available cylinder barrels, pistons, poppet valves, etc. What you would be creating, in effect, would be a Gnome-Rhône 14K to British standards (the 14K and Mercury having the same bore and stroke).

In his Aircraft Engine Historical Society paper - Comparison of Sleeve and Poppet-Valve Aircraft Piston Engines - Robert J. Raymond says that "Fedden was ... having trouble adapting his four-poppet-valve arrangement to a two row engine." Does anyone know exactly what the nature of that 'trouble' was? (I have a vague memory of it having something to do with the push-rod arrangement on Bristol's poppet-valve engines.)

Edit: I found a  thread about developing Bristol engines on WW2Aircraft.net that touches on valves and their push-rods:
-- https://ww2aircraft.net/forum/threads/bristol-radial-engine-development.14674/

There, red admiral made an interesting comparison with the Alfa Romeo 135. Basically, the front row is a typical Bristol poppet-valve arrangement. The rear row simply reverses things with the push-rods being behind each cylinder barrel. The exhaust remained Bristol in style - outlets to the front, individual exhaust pipes heading forward towards a collector pipe.
"She always found it peculiar to encounter a time she had actually lived through rendered as a period." William Gibson, Zero History

Re: A Canadian Raven in Spain
« Reply #19 on: July 30, 2021, 03:58:54 AM »
All good points Chris. Having previously posited a 'Bristol Engines (Canada)', I am now thinking that some variation on the RW British Aeroplane Engines Limited would be more productive.

Being separate from Bristol Aero-Engines Limited would free-up the firm from Roy Fedden's obsession with sleeve valves. (Licensing the Mercury allows you to do as you will with that design.) So, instead of Hercules, a Canadian-controlled British Aeroplane Engines could be developing your 'Double-Mercury'.

Outputs would be equivalent to early-model Hercules but would be using available cylinder barrels, pistons, poppet valves, etc. What you would be creating, in effect, would be a Gnome-Rhône 14K to British standards (the 14K and Mercury having the same bore and stroke).



Thanks for posting that.

So, I think a two-row Bristol Mercury/Pegasus is entirely possible, using some good ol' Canadian get-it-done mentality. And of course, some quality material assistance from our southern neighbour.

I can see our version of the Lancaster fitted with 4 x 18-cylinder Pegasus engines flying higher and faster the the regular Lancs.



Chris

In his Aircraft Engine Historical Society paper - Comparison of Sleeve and Poppet-Valve Aircraft Piston Engines - Robert J. Raymond says that "Fedden was ... having trouble adapting his four-poppet-valve arrangement to a two row engine." Does anyone know exactly what the nature of that 'trouble' was? (I have a vague memory of it having something to do with the push-rod arrangement on Bristol's poppet-valve engines.)

Edit: I found a  thread about developing Bristol engines on WW2Aircraft.net that touches on valves and their push-rods:
-- https://ww2aircraft.net/forum/threads/bristol-radial-engine-development.14674/

There, red admiral made an interesting comparison with the Alfa Romeo 135. Basically, the front row is a typical Bristol poppet-valve arrangement. The rear row simply reverses things with the push-rods being behind each cylinder barrel. The exhaust remained Bristol in style - outlets to the front, individual exhaust pipes heading forward towards a collector pipe.
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Offline apophenia

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Re: A Canadian Raven in Spain
« Reply #20 on: July 30, 2021, 07:05:53 AM »
Yup. Bring on those Dollar-a-Year men, Ottawa!

So, your 'Pegasus 18' would have a displacement of 3,506 cid. Diameter would be the same at 55.3 inches. Assuming the same compression ratio, etc., power should be about 1,926 hp for take-off? That should move the Lancs along nicely  :smiley:

Going by that crude arithmetic, a 'Pegasus 14' would displace 2,727 cid and produce about 1,498 hp (T/O). Perhaps the diameter would be reduced very slightly? Almost certainly easier to cool than a 'Pegasus 18' too.

By comparison with these 2-row Pegasus concepts, the Wright R-2600 displaced 2,604 cid with a diameter of 55 inches. Early version produced around 1,400 hp, later versions up to 1,720 hp (due to higher compression ratio?).

The Hercules, by contrast, had the same stroke and bore as the smaller Mercury ... but that reduced stroke, the Hercules still had a 55 inch diameter  ???
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Offline jcf

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Re: A Canadian Raven in Spain
« Reply #21 on: Yesterday at 07:11:00 AM »
Hercules diameter is 52", the 55" is the diameter of the power egg installation which
includes the cowling.
“Conspiracy theory’s got to be simple.
Sense doesn’t come into it. People are
more scared of how complicated shit
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Offline jcf

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Re: A Canadian Raven in Spain
« Reply #22 on: Yesterday at 07:48:29 AM »
Wright 776C14BB1 (R-2600-22) Spec. No. N776B had a take-off rating of 1900hp at 2800rpm, normal
operational rating 1600/2400. It had a two-speed supercharger, ratios 7.06:1/10.06:1, compression
ratio 6.9:1. It was used in the TBM/TBF-3 and the SB2C.

Looking at the numbers engine sub-types with identical supercharger and compression ratios can have
higher or lower horsepower ratings i.e. the R-2600-29 Spec. No. 655C used in the A-20H, B-25G/H/J
has the same supercharger and compression ratios as the R-2600-22 but it's rated at 1700/2800 and
1500/2400.

BTW the original GR2600A2 had a TO rating of 1550/2400 and a compression ratio of 7.1:1, only one
other variant had that same compression ratio, all others had a lower ratio. The lowest being 6.1:1 of
the R2600-12 Spec. No. 776 used on the Martin PBM-3, but it was still rated at 1700/2800 and 1500/2400.

The differences clearly have more to do with the operational requirements of the aircraft type than any
dramatic differences between the various subtypes of the engine.
“Conspiracy theory’s got to be simple.
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Re: A Canadian Raven in Spain
« Reply #23 on: Yesterday at 08:05:47 AM »
One option is to ditch the four-valve head for a two-valve head?
“Conspiracy theory’s got to be simple.
Sense doesn’t come into it. People are
more scared of how complicated shit
actually is than they ever are about
whatever’s supposed to be behind the
conspiracy.”
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Offline apophenia

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Re: A Canadian Raven in Spain
« Reply #24 on: Yesterday at 11:07:18 AM »
Thanks for the correction and clarifications Jon  :smiley:

One option is to ditch the four-valve head for a two-valve head?

Yes, in the example of a 'Twin Mercury' that would bring the engine fully in line with the Gnome-Rhône 14K (although hopefully better cooled!). If making the change to two-valve heads, would you retain the existing cylinder barrels? Or take the opportunity to shift the exhaust outlets to the rear and restrict parts commonality to pistons, connecting rods, etc.?
"She always found it peculiar to encounter a time she had actually lived through rendered as a period." William Gibson, Zero History