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Russ, I am sorry but have no idea what you are talking about.

The Blackburn contract for B.20 was not cancelled, there was no reason to do so.

When R1/36 was selected, Saro got the combat acft production contract for Lerwick.

Blackburn's design was so interesting and promised so much that they got a technology development contract for B.20 (2 flying prototypes plus a lot of design evaluation and data crunching).

- In Sept 39 construction of the second flying prototype was suspended. The fuselage and 'other major components' were simply rolled into the tech evaluation and testing side of the program. They still existed as late as 1943 AFAIK because they were valuable, and needed for B.32 and B.40 development.

- This was because Air Min was evaluating a new tech.

When the prototype crashed, the flying T&E program ended (obviously) but that was all.

The rest of the program continued on, data was still being crunched from the truncated flying program and development of the planing bottom and float retraction gear continued because they knew they needed both for B.32, B.40 and B.44. (B.44 grew out of Firebrand - something not well known)

All of this was rolled straight into the Firebrand program and the B.40 program. It was also already in use for B.32 (which used the retractable floats but not he retractable planing hull in an otherwise rather conventional 4 engined flying boat). Firebrand was a short-range interceptor at the time, and the RAF was interested in a B.43 version, a twin-float fighter. They did a bunch of work resulting from the B.20 program and realised that they could get a much faster fighter by using a retractable hull float and wing tip floats. So B.43 Firebrand Floatplane metamorphisised and became B.44.

Meanwhile, B.40 had been under development from a meeting held on 24 April 1940, and its design basis was B.20. The Air Ministry decided to go with B.40 as a machine to do better and more economically what Sunderland already did well, using two Centaurus engines.

This is why I am confused by your comments - the B.20 technology development contract was never cancelled and they never had a production contract. There was no need to cancel a technology development contract with immediate application to two (and soon three) other projects. Why would they cancel a contract investigating a new technology which had shown such a remarkable performance increase for large flying boats?

A lot of this came also from the failure of Lerwick, which acted to really confirm what they knew as soon as B.20 flew - that the decision to build and fly B.20 to prove the concept was a real winner. It flew fine (in fact much more than fine), while Lerwick showed that a deep hull straight wing non-parasol twin engined flying boat was a dead end. If Saro could not make it work nobody could. Such boats just had too many lateral stability, yaw, and stall problems with the short and stumpy fuselage. So a twin engined flying boat had to be a biplane, a parasol, or a gull wing..... Unless you used a retractable hull planing float, and THAT design was faster than all the other designs. But in late 1938, that speed advantage was not seen as a very high priority.

Here in FFO, with the whole French coast occupied AND no bombers to use for this role; that speed suddenly becomes extremely important.

So I am quite confused at your comment. Have you maybe crossed wires with the cancellation of Saro's production contract for the Lerwick?

In FFO, the RAF has little need for Catalina. They bought 650 of them in OTL, but with Stirling MPA and B.20, (and with the French needing them too and that has to come from British numbers) I really cannot see more than a hundred or so being needed.

Cheers: Mark

This is why I do not understand this discussion. We all know the same data, we all know why the meeting on 24 April 1940 formally canceled the flying evaluation of the B.20 project - because of the crash on 7 April 1940. They had the option of finishing the second partly built prototype, but decided not to. I guess (note the caveat) that they reckoned they had enough data from the existing data from flying trials to know that the technology worked very well indeed.

This was not full cancellation of the CONTRACT. It continued and this is obvious from their move to B.40, really a development of B.20. The technology development and evaluation contract had more than one part (quite typical even now, as we all know), and sure, one part got canned, but not all of it.

As for the drivers, I have already discussed them, and you've covered part of one of the major ones in a bit of depth: the Med.

QUOTE:
But here's the snag - the requirement has not gone away and it has not been shelved. In fact, if has become much more important. Much more interestingly, it places a real premium on HIGH SPEED. The original need to recce the North Sea and Baltic approaches and Med are all still there. Only the Med has grown teeth because the Germans occupy the south of France. Any RAF recce bird sniffing around Marseilles knows for sure that it has to go in there fangs out and hair on fire because it is going to get real nasty real fast. Worse, the French Atlantic coast and Norway and the southern North Sea are added to the list. CC in FFO now really, really needs a very fast recce flying boat! Catalina is useless for the task of recce along the French and European costs - it's a deathtrap.

What to do? In OTL they used bombers for the job then switched to Mosquito. But we can't do that in FFO because we have cut Bomber Command down and they have first call on what is left of the bomber resources (especially the Mosquitoes). There is one bomber available - Whitley. It's no good as it is too slow. Hampden is both too slow and defenceless.

So they will look again at B.20, just at the time when RR is fixing Vulture's most egregious problems and making it reliable enough to use.
UNQUOTE

So to list them:

1. Existing drivers
a. Recce the North Sea
b. Recce the Baltic Approaches
c. Do it cheaper than with Sunderland
NOTE: These and a penchant for a low-risk solution got Saro the contract for R.1/36

2. New Drivers all to be done inside enemy fighter cover
a. Recce the whole French Atlantic coast
b. Recce the Norwegian coast
c. Recce the Med (your point that "The Med. side of NA needs a plane that does not need runways, is fast in case of Italian planes and has fairly good range. Also the fact that the B.20 Blackburn can fly on one engine in a combat zone" is a good extension/explanation of this)
d. All of the above place a high premium on speed

3. Limiting factors
a. No fast bombers are available for the job (unlike per OTL)
b. Lerwick has FAILED (it is not really even very airworthy, let alone combat worthy)

B.20 speed

The prototype reached 345mph on its first high speed run (low altitude too). Source for this is the 'memorial website to Harry Bailey, Duncan Roberts and Sam McMillan at http://freespace.virgin.net/john.dell/blackburn_b20.htm

The reason I am waffling on about 350mph is that in FFO the 'fixed Vulture' is a bit more powerful than the OTL unfixed Vulture.

Now, why B.20 (Vulture) and not B.40 (Centaurus) in FFO. Easy: the driver for B.40 was to replace Sunderland. In FFO, what is needed quite quickly is not a Sunderland repalcement, but something to replace Lerwick and to operate in the teeth of enemy fighter opposition. And they already have that in B.20 once the Vulture is fixed. That's the keystone to the whole deal, and in FFO, Vulture gets fixed for a very solid set of reasons.

I hope this is sorted now, because we seem to be discussing the same things from very close to the same perspective.

Cheers: Mark

PS: Connection will be spotty, I am about to head to Darwin for the week for a Conference - no rest for the wicked)

Thanks, Benedict, very true!

Obviously, this was not a predicted or desirable outcome in OTL. SO it was also a driver in OTL, of course.

The difference in FFO is that this driver is effective (in was NOT effective in OTL). This is due to other factors like fixing Vulture, etc.

CHeers: mark

Russ

Here's what I think is missing.

The B.20 had 2 prototype orders placed after it lost the contract to Saro, construction on the second one was suspended in the fall of 1939, the other continued till finished and a series of test began in April 1940. On April 7th the prototype crashed after conducting high speed testing. After that the B.20 as a plane was shelved. On April 24th specification (R13/40) was placed as a replacement aircraft for the Sutherland.

Comment: This is the bit that does not work in FFO - because there is no need to issue R.13/40 for "an acft to do more cheaply what Sunderland already does well". There IS a need for a high speed coastal acft.

The Aircraft was to use the lessons and ideas of the B.20 and was to be the B.40.

So what in FFO ( which has its POD in June 1940 ) caused the B.20 to be resurrected as a plane?

Comment: Already explained a number of times:

QUOTE:

But here's the snag - the requirement has not gone away and it has not been shelved. In fact, if has become much more important. Much more interestingly, it places a real premium on HIGH SPEED. The original need to recce the North Sea and Baltic approaches and Med are all still there. Only the Med has grown teeth because the Germans occupy the south of France. Any RAF recce bird sniffing around Marseilles knows for sure that it has to go in there fangs out and hair on fire because it is going to get real nasty real fast. Worse, the French Atlantic coast and Norway and the southern North Sea are added to the list. CC in FFO now really, really needs a very fast recce flying boat! Catalina is useless for the task of recce along the French and European costs - it's a deathtrap.

What to do? In OTL they used bombers for the job then switched to Mosquito. But we can't do that in FFO because we have cut Bomber Command down and they have first call on what is left of the bomber resources (especially the Mosquitoes). There is one bomber available - Whitley. It's no good as it is too slow. Hampden is both too slow and defenceless.

So they will look again at B.20, just at the time when RR is fixing Vulture's most egregious problems and making it reliable enough to use.

UNQUOTE

So to list them:

1. Existing drivers

a. Recce the North Sea

b. Recce the Baltic Approaches

c. Do it cheaper than with Sunderland

NOTE: These and a penchant for a low-risk solution got Saro the contract for R.1/36

2. New Drivers all to be done inside enemy fighter cover

a. Recce the whole French Atlantic coast

b. Recce the Norwegian coast

c. Recce the Med (your point that "The Med. side of NA needs a plane that does not need runways, is fast in case of Italian planes and has fairly good range. Also the fact that the B.20 Blackburn can fly on one engine in a combat zone" is a good extension/explanation of this)

d. All of the above place a high premium on speed

3. Limiting factors

a. No fast bombers are available for the job (unlike per OTL)

b. Lerwick has FAILED (it is not really even very airworthy, let alone combat worthy)

B.20 speed

The prototype reached 345mph on its first high speed run (low altitude too). Source for this is the 'memorial website to Harry Bailey, Duncan Roberts and Sam McMillan at http://freespace.virgin.n...n.dell/blackburn_b20.htm

The reason I am waffling on about 350mph is that in FFO the 'fixed Vulture' is a bit more powerful than the OTL unfixed Vulture.

Now, why B.20 (Vulture) and not B.40 (Centaurus) in FFO. Easy: the driver for B.40 was to replace Sunderland. In FFO, what is needed quite quickly is not a Sunderland repalcement, but something to replace Lerwick and to operate in the teeth of enemy fighter opposition. And they already have that in B.20 once the Vulture is fixed. That's the keystone to the whole deal, and in FFO, Vulture gets fixed for a very solid set of reasons.

If the drivers are there then we should come up with how it got restarted.

Comment: Explained as above, with drivers.

What I have going through my head right now is that the Lerwick is pressed into duty more than in otl in June 1940 ( the POD ) to help with emergency Convoy escorting and recon in support of the French. Losses are terrible and many accidents occur.

Comment: Basically, they could try to do this - the result would be that the one SQN using them will simply say that the machine is not airworthy enough for the task and his aircrew are not just to be wasted. This is recognised anyway - Lerwick is already known to be a total failure. So we can do this without 'killing' people. There were only 21 Lerwicks built.

The ministry, realizing that the qualities they need are very similar to the B.20.

Comment: They already know this from the FFO drivers and the OTL drivers.

An initial order is placed for B.20's under the condition that it will not interfere with the B.40 program in August 1940. With Jig's and all the Technical information available and only a few issue to correct from recommendation from the Board investigating the loss of the first B.20, production should be able to begin sometime in November 1940. With Japanese buildup seen in June 1941 a further order is placed and the conditions for changing the B.40's requirements are shifted (with a possible 4 engine version ordered instead ) and the B.40 program is not cancelled in January 1942.

Comment: B.40 was a longer ranged, slower, Centaurus-engined machine. With Vulture fixed, and speed a requirement, there are simply no drivers for it. I get the sense that B.40 was a fairly desperate effort by Blackburn to get something into production. In the end, the basic case failed because it did not make sense. This was the same reason Manchester and Warwick failed - two-engined heavy acft are a dumb idea.

Imah:I also can't see why Norway would be suddenly a driver compared to OTL.

Comment: Imah, it isn't. It has the SAME weighting in FFO as in OTL. In OTL, this was not enough to get B.20 into production. In FFO, WITH THE OTHER FFO DRIVERS, it is enough.

And for the MTO (western Med being under French responsability), remember that the French control Corsica and Sardinia and have the planes/seaplanes (and even fast planes like VG.33, MB-17x, Amiot 35x and of course the arriving US planes) to recon south of France (and there are plenty of airfields available).

Comment: We have never once considered the RAF offering B.20 to Algiers. They would not be able to produce enough of them and would neve have enough for Imperial needs. Rolls Royce will really struggle to produce enough 'fixed Vultures' for Tornado, Barracuda and B.20. There is almost no chance of any machine using Vulture being in AdA service.

Now, if the British want to take advantage of the French decision to continue the war to improve their OWN situation over the North Sea, Channel and Atlantic, then why not go on with the B.20.

Comment: Precisely!

But there is no need to justify the plane with the Med'.

Comment: This is just one more driver among the mix, there has never been the slightest suggestion that B.20 is justified on this basis. It is justified on an OTL and FFO driver mix. The RAF wishes to similarly improve its situation in the Med as on the European western coastlines. They have an extensive flying boat infrastructure in the Med, but nothing fast enough to operate from it. In OTL, they used bombers for that task. Losses were high. In FFO, they do not have the bombers available, so the options are to not do the task, or do it with B.20.

Moreover, it seems that one of the reasons for the cancellation of the project was the "panic" of June/July 40. Hence the idea to say "no panic in FFO", therefore a lot of things can change. I think we must be very careful here not to develop a best-case for GB. The loss of continental France will still be seen as a nightmare for the British. GB is still in first line against Germany. Only a handful of selected projects (for the RAF, RN or army) will see their fate changed because "less panic".

Comment: Partly true. The interconnections to that one event of 'less panic' are quite profound, as the Aviation Paper says in great detail. There is very powerful 'butterfly effect', as we have all seen. Just 'less panic' has resulted in non-cancellation of the RAF move to high altitude, for example, just as the fact of France continuing on has destroyed the entire OTL rationale for Bomber Command to call on all available UK resources. In turn, that has meant a much, much smaller Bomber Command and use of heavy bombers in the Med (the Stirling force) and Far East (the Manchester force).

In FFO, Bomber Command is 30-50% of the size it was in OTL.

The matter is very, very far from 'GB best case' and has resulted in some really 'high friction' decisions: forcing Gloster Reaper on the Australians; forcing the VHA Wellington into operational service; forcing the Manchester to stay in production (only bright spot there is fixing Vulture); denying Mosquito to ANYONE except Bomber Command until at least early 1944; killing Australian Beaufighter construction; being forced to try and get too much from Hurricane; forcing redesign of Whirlwind to fix its problems; etc etc etc. In addition, some OTL disasters/problems remain: Botha; Albacore; continued production of Battle into 1943; etc etc.

The bright spots are Vickers Victoria, Stirling MPA, B.20 'Brisbane', and a focus on Transport Command which allows York and 'FFO Albemarle' to enter quantity production very early.

The outcome is a very good balance - which is merely what you expect from France fighting on. The RAF does not become distorted as it did in OTL by becoming 'the only way we can hit back at the Germans'. It remains a balanced force.

Cheers: Mark

Russ,
1) We need the RAF and any other air force to make mistakes. Trying to do the long ranged, heavy, 2 engine aircraft will still have to be tried to find out that they do not work.

Comment: Agreed. That is why we have Vickers Warwick and Avro Manchester. Warwick is a complete failure as per OTL only worse in some ways. Manchester, while still produced in FFO, is actually an even worse mistake because it retains the type in production (as a 'foil' to BC being forced to send Lancasters out to Asia) in some numbers.

2) If Vulture is fixed then the B.40 does not need to use Centaurus.

Comment: True. Of course, with Vulture fixed, B.20 can be produced, and there is no need for B.40 at all!

3) If Rolls Royce and the air ministry hold off canceling the Vulture till after September 1941 ( its not going to get fixed any sooner ), the lessons Rolls Royce learns at Packard will fix the Super charged Peregrines problems used in the Vulture. If they wait till March 1942, the introduction of the V-3420 into the B-29 program will also help refine the design if they talk to each other ( Allison and Rolls ).

COmment: More for Shane to comment on. Peregrine is not Vulture, they are different engines. The problems with Vulture were well known and were not hard to correct.

Cheers: Mark