January 1936: build your RAF

[Shortround6]

Unless you have absolute dictatorial powers a lot of this is not going to happen. Yes, Bristol made a mistake in trying to offer different 4 engines from 24.9 to 28.7 liters. But in hindsight it was the Taurus that was the Mistake. Since a Mercury is pretty much a Pegasus with 1 inch less stroke and a good part of the tooling existed before 1936 you don't save much by knocking of the Mercury. Perseus used Hercules cylinders, sleeves, pistons, at least to start. Only other program they were really fooling with was the Centaurus and telling Bristol before the war broke out that they would be kept in 2nd or 3rd place (no 2000 hp engine) among British engine makers wasn't going to happen.

The A-S Tiger didn't need just new bearings, it needed a new crankshaft and new crankcase to hold the bearings. From some stories J. Siddeley could be a pretty hard headed fellow.

The trouble with trying to get a "BIG" Canadian company to build any sort of aircraft engines in 1936-40 period is there weren't any BIG Canadian companies with large production line experience that aren't closely tied to American companies or that weren't already spoken for ( Canadian auto/truck plants built large quantities of vehicles for the Allies).

In 1938 in Canada the Aviation engine "industry" consisted of a repair and overhaul facility owned and run by Armstrong-Siddeley located inside the works of the Ottawa Car manufacturing company (makers of street cars). Perhaps some small production of small A-S engines did take-place there, There was considerable expansion during WWII.

But Please remember that ANY large scale production of most types of war material is highly dependent on the US, at least for the first few years. The Majority of machine tools will have to come from the US as will the majority of fittings/specialty parts and major sub assemblies ( carburetors, generators.starter motors, magnetos, etc). Allison had over 3000 sub-contractors supply parts/materiel for the Allison engine. It is going to take time ( a number of years) to build up even a part of the support system that a major aircraft engine factory would need in Canada.

I am not trying to put down or belittle the Canadians in anyway. They performed near miracles in producing certain types of war material but there were limits to how many new factories that could be built/equipped and managed in Both Canada and the US.

You might be able to get an aircraft engine factory built an into operation by 1940 but what do you have to give up for it?

What American engine factory gets shorted machine tools?
What other Canadian war factory gets shorted tooling, or management personnel or engineers or ?????

Canada built about 200 aircraft total in 1938 including DH Tiger Moths and was subcontracting parts for a number of other aircraft (Blackburn Shark?)

The Fairchild (Bristol) Bolingbroke (Blenheim) may help shed light on this. The "plan" started in 1937 with the Canadian government accepting the need to modernize and expand the RCAF. A modified Blenheim is selected as the aircraft needed and a suitably modified prototype flies in England on Sept 24 1937. Of 9 British produced Blenheim IVs (same thing as a Bolingbroke)earmarked as pattern and evaluation aircraft to be sent to Canada from 1938 production only 4 make it. There was an initial order for 18 aircraft from the Canadian production line, even with a large amount British supplied components the first Canadian built aircraft is not delivered until Nov 15 1939 and the 18th aircraft is delivered Aug 28th 1940. In the meantime the Bolingbroke has been adapted to American structural and equipment standards and called the Bolingbroke IV. First Bolingbroke IV was delivered Jan 30 1941.

Now maybe that could have been speeded up somewhat but there would have been no waving of a magic wand and the creation of a large factory capable of producing thousands of aircraft engines in the late 30s.

And lets think about this. IF the Canadians had been capable of build a large Merlin Factory in 1939/40 WHY did the British approach the US and try to get Ford at first and then Packard to build the Merlin?

WHY did the British (in 1939) pay Pratt Whitney enough money to double the floor space of their factory to meet British orders ( after the French had already paid to double the size of the original factory).

Why were they paying the US and US companies rather than keeping the money inside the commonwealth?

 

[tomo pauk]

Unless you have absolute dictatorial powers a lot of this is not going to happen. Yes, Bristol made a mistake in trying to offer different 4 engines from 24.9 to 28.7 liters. But in hindsight it was the Taurus that was the Mistake. Since a Mercury is pretty much a Pegasus with 1 inch less stroke and a good part of the tooling existed before 1936 you don't save much by knocking of the Mercury. Perseus used Hercules cylinders, sleeves, pistons, at least to start. Only other program they were really fooling with was the Centaurus and telling Bristol before the war broke out that they would be kept in 2nd or 3rd place (no 2000 hp engine) among British engine makers wasn't going to happen.

No dictatorial powers, just buyer's powers
I've never stated that Centaurus need to be axed. The Taurus is a good candidate for that, and actually I'd very much love to see the Centaurus being developed earlier.

The A-S Tiger didn't need just new bearings, it needed a new crankshaft and new crankcase to hold the bearings. From some stories J. Siddeley could be a pretty hard headed fellow.

In other words, A-S should churn out the Tigers and Cheetahs for aircraft that are away from limelight, like transports, trainers, Coastal Command needs, and Whitley until something better is available?

<snip>
Why were they [UK and France] paying the US and US companies rather than keeping the money inside the commonwealth?

Question is how much the Europeans have had confidence in the Colonials? Okay, USA is a world powerhouse, things cannot go terribly wrong there. However, the Australians managed to license build the Twin Wasps Jr and Twin Wasp, later the Merlins. The CAC was established in 1936.

And lets think about this. IF the Canadians had been capable of build a large Merlin Factory in 1939/40 WHY did the British approach the US and try to get Ford at first and then Packard to build the Merlin?

The 1939/40 is way too late to commence with Merlin project in Canada or Australia. The negotiations have to start in 1936, with factory being built in 1937, or latest in 1938.

WHY did the British (in 1939) pay Pratt Whitney enough money to double the floor space of their factory to meet British orders ( after the French had already paid to double the size of the original factory).

Same thing: when things got ugly, only the big US companies have had capacity to turn the money other resources into workable engines quickly enough. Commonwealth needs an earlier start.

To move a bit from engines: how should the needs for a land-based torpedo bomber be addressed?

 

[Shortround6]

No dictatorial powers, just buyer's powers

In other words, A-S should churn out the Tigers and Cheetahs for aircraft that are away from limelight, like transports, trainers, Coastal Command needs, and Whitley until something better is available?

In 1935-36-37 the engine companies were still looking at/for foreign and commercial sales. The Government could not forbid a company from working on an engine, at least to prototype status. They did their best to discourage Fairey.

The Tiger faded from sight pretty quick in the late 30s, with some justification. A-S should, as historically, churn out the Cheetah.

However, the Australians managed to license build the Twin Wasps Jr and Twin Wasp, later the Merlins. The CAC was established in 1936.

Established in 1936. Got license for and started production of NOT the Twin Wasp Jr. but the 9 cylinder Wasp R-1340. and that was closer to 1938. Production of the R-1830 followed several years later with the Merlin several years after that.

It takes time to build up from almost scratch." the first CA-1 Wirraway, RAAF serial A20-3, made its maiden flight on 27 March 1939" and the 6th was delivered by the beginning of Sept. 1939.

The 1939/40 is way too late to commence with Merlin project in Canada or Australia. The negotiations have to start in 1936, with factory being built in 1937, or latest in 1938.
Same thing: when things got ugly, only the big US companies have had capacity to turn the money other resources into workable engines quickly enough. Commonwealth needs an earlier start.

The Commonwealth had to start even earlier. and then you are back to the problem of which engine/aircraft you tool up for. The Commonwealth projects also need machine tools and equipment that they cannot manufacture themselves without adding even more delays so the machine tools and equipment have to come from either the UK (delaying the shadow factory program there) or the US.

To move a bit from engines: how should the needs for a land-based torpedo bomber be addressed?

Simple way. Ditch both the Botha and the Beaufort (except for enough Beauforts to work out construction, 2-4?) and use Whitleys until you can hang a Torpedo under the Beaufighter.

 

[tomo pauk]

In 1935-36-37 the engine companies were still looking at/for foreign and commercial sales. The Government could not forbid a company from working on an engine, at least to prototype status. They did their best to discourage Fairey.

The companies can, by all means, sell the engines abroad. It's the RAF's engines where we will be calling the shots
Fairey should be promised a good deal of airframe production, provided they sell their engine division to RR, Napier or Bristol?

The Tiger faded from sight pretty quick in the late 30s, with some justification. A-S should, as historically, churn out the Cheetah.

+1 on that.

Established in 1936. Got license for and started production of NOT the Twin Wasp Jr. but the 9 cylinder Wasp R-1340. and that was closer to 1938. Production of the R-1830 followed several years later with the Merlin several years after that.

I'd be satisfied with Merlins coming out from Canada by mid 1939.

It takes time to build up from almost scratch." the first CA-1 Wirraway, RAAF serial A20-3, made its maiden flight on 27 March 1939" and the 6th was delivered by the beginning of Sept. 1939.
The Commonwealth had to start even earlier. and then you are back to the problem of which engine/aircraft you tool up for. The Commonwealth projects also need machine tools and equipment that they cannot manufacture themselves without adding even more delays so the machine tools and equipment have to come from either the UK (delaying the shadow factory program there) or the US.

Canada can build Merlins, Australia the Pegasus, later they should build the next Bristol with substantially more power.Canada and Australia should receive the licenses to build training A/C, plus Hurricanes (earlier Canada, later Australia once the production of Merlins ramps up in UK and Ca)?

Simple way. Ditch both the Botha and the Beaufort (except for enough Beauforts to work out construction, 2-4?) and use Whitleys until you can hang a Torpedo under the Beaufighter.

Guess you mean Hampden, rather than Whitley? Would the Blenheim with Pegasus be much of a torpedo bomber?

 

[fastmongrel]

Simple way. Ditch both the Botha and the Beaufort (except for enough Beauforts to work out construction, 2-4?) and use Whitleys until you can hang a Torpedo under the Beaufighter.

I really hope that was a brain fade there, sending a Whitley to torpedo bomb would have been kinder to just shoot the crew on the ground.

 

[Shortround6]

More of a brain fart guys

The companies can, by all means, sell the engines abroad. It's the RAF's engines where we will be calling the shots
Fairey should be promised a good deal of airframe production, provided they sell their engine division to RR, Napier or Bristol?

Doesn't quite work that way. British are short of "engineers" which covers not only designers but office staff down to draftsmen. The only way to really speed up some programs is move some "engineers" from one program to another but if you don't have the authority to actually shut down a private company program (which they are trying to sell to another country or for airline use) then you don't have any way to shift any real number of "engineers".

The Fairey engine "division" was never more than a small experimental shop. The "first" Fairey engine was the Felix of of 1926 which was actually 50 imported Curtiss D.12 engines.

This was followed in the early 30s by the V-12 Prince and Super Prince of 25.54 liters, 3 engines had accumulated 550 hours by the end of 1934. One engine was installed in an airframe.

This was followed (or perhaps in parallel ) by the H-16 Prince an H-24 Monarch using the same size cylinders as Prince for 34 and 51 liters total number of these engines doesn't seem to be known but seems to very small. 2-3 Battles are used as test beds and while the first Monarch drawings are dated 29 Aug 1932 the engine doesn't pass a a 50 hour type test until until May/June of 1939 (with first aircraft installation predating that in Oct 1938.) The program creeps along until 1943.

Fairey probably built under a dozen engines in 8-10 years and there is no way to tell how much was contracted out (like block castings) and how much may have been done in house.

 

[nuuumannn]

Let's not underestimate the Beaufort; it was a good aeroplane. The Botha wasn't, but it was the insurance policy, so easy to ditch. The Beaufighter is the obvious choice and if I had a choice between the Hampden and Beaufort, I'd choose the latter. If we are getting rid of the Taurus, the answer is simple; the Beaufort II and all the Aussie Beauforts were powered by American engines.

 

[parsifal]

why not go straight to the Beafighter. It was pretty good in the tactical strike role and much more survivable. Im a big beafort fan, but it had its limits. so too did the Beaufighter, but it was clearly the superior aircraft.

Just sayin

 

[tomo pauk]

Without an earlier start more focused development of the Hercules (provided by cancellation of the Taurus?), there is no Beaufighter? Alternatively, we might want to install Merlin on it, the shortcoming being too many designs want the Merlin?

...
Doesn't quite work that way. British are short of "engineers" which covers not only designers but office staff down to draftsmen. The only way to really speed up some programs is move some "engineers" from one program to another but if you don't have the authority to actually shut down a private company program (which they are trying to sell to another country or for airline use) then you don't have any way to shift any real number of "engineers".

The private company, eg. Bristol, has already developed 2 engines that offer ~1000 HP. How much there is reason to design another engine of 1000+ HP (Taurus), since company is more than capable to aim for the 1500 HP mark (Hercules)? RAF can simply say: no, we won't buy another 1000 HP engine, but we will buy a 1500 HP one.
I'm not certain that RR was designing the Peregrine for civil use, and they definitely were designing the Exe for the needs of FAA. Offer the FAA with a low alt Merlin (ie. future Mk.VIII), to be shortly followed by an improved version with two speed supercharger. Both FAA and RAF will receive either more, or better Merlin in case Exe and Peregrine are axed.

The Fairey engine "division" was never more than a small experimental shop. The "first" Fairey engine was the Felix of of 1926 which was actually 50 imported Curtiss D.12 engines.

This was followed in the early 30s by the V-12 Prince and Super Prince of 25.54 liters, 3 engines had accumulated 550 hours by the end of 1934. One engine was installed in an airframe.

This was followed (or perhaps in parallel ) by the H-16 Prince an H-24 Monarch using the same size cylinders as Prince for 34 and 51 liters total number of these engines doesn't seem to be known but seems to very small. 2-3 Battles are used as test beds and while the first Monarch drawings are dated 29 Aug 1932 the engine doesn't pass a a 50 hour type test until until May/June of 1939 (with first aircraft installation predating that in Oct 1938.) The program creeps along until 1943.

Fairey probably built under a dozen engines in 8-10 years and there is no way to tell how much was contracted out (like block castings) and how much may have been done in house.

Thanks for the overview.

Let's not underestimate the Beaufort; it was a good aeroplane. The Botha wasn't, but it was the insurance policy, so easy to ditch. The Beaufighter is the obvious choice and if I had a choice between the Hampden and Beaufort, I'd choose the latter. If we are getting rid of the Taurus, the answer is simple; the Beaufort II and all the Aussie Beauforts were powered by American engines.

Blackburn can build either Hampden, or Blenheim with Pegasus engines? Ditto Australia? I'd love to see the Beoufighter as an aircraft with a thinner wing.

Some early war British engines, from Flight archives. Black lines 'bracket' take off power, between blue and 1st black line is max altitude regime. Please, open the pic separately, for bigger resolution:

 

[Shortround6]

The Taurus was supposed to offer the same or slightly more power than a Pegasus in a smaller diameter engine. 46.2 in vs 55.1 with 11.7 sq ft of frontal area vs 16.8sq ft. 70 % of the frontal area of the Pegasus. In the mid/late 1930s this was seen as a considerable advantage as low drag cowlings of radial engines were nowhere near what they would be in 1942/43/44. The Taurus also "offered" better fuel economy due to higher compression, part because of the smaller cylinders and part due to the sleeve valves. The better fuel economy may or may not have been achieved due to other things, I don't know. It was an attractive proposition if you were looking for a 1100hp engine. The problems start to come in with the whole sleeve valve production problem, the Taurus suffering from over heating and the fact that by 1940-41 1100hp (or less) was too little for a "new design" entering service. Taurus was already turning 3250 rpm and even with it's small cylinders that was 3023fps piston speed. While a Taurus might have been able to match an R-1830 ( 20% less displacement but turned 20% more rpm, roughly) It is rather obvious that it was going to hit a wall due it's size even IF more boost is used with better fuel ( air cooled engines did not accept large increases in boost without major changes to the cooling fins, among other changes).

Taurus was enough trouble that the British were planing to switch to the P&W R-1830 for British built planes, until the ship carrying the first 200 engines was sunk.

The Hercules hit the same main problem, there may have been minor problems in development but the big one was that while Bristol ( and later Napier) could make sleeves in small quantities for prototype a or low production rates that worked(for more than around 20 hours) they could not make them in large quantities. Since this is a rather specific problem assigning more "general" engineer staff or men who specialized in other areas (supercharger men, stress men, etc) may not get you much.

Another problem was that needs had changed rather rapidly. an airframe that might have been OK with 1000 hp engines in 1938/39 now needed armor, self sealing fuel tanks, more defensive guns, etc and performance dropped. Expectations also rose and while a 1000lb bomb load seemed fine in 1934 (Blenheim vs 460lb Hart) and 1500lbs in The Beaufort was a 50% increase in 1937/38 1500lb internal load was not all that hot in 1940/41 for a twin engine bomber.

Some of these planes were a bit on the marginal side. The Bolingbroke tired two other engines besides the Mercury when fears of a shortage of British supplied engines ( ships sunk by German U-boats) came up. 14 or so were powered by P&W R-1535 Twin Wasp Jr. but lack of power at/near gross weight ( plane could not maintain altitude on one engine) forced a reduction in bomb load to 500lbs. One Plane was given 9 Cylinder cyclones (an older version NOT 1000-12000hp Cyclones) but the larger engine cowls restricted vision, perhaps not too good on the Blenheim to begin with and one reason for the raised cockpit on the Beaufort? There are other reasons but but hanging Pegasus engines with their 9-10 in bigger diameter cowlings on the Beaufort doesn't do much for either performance or field of view.

 

[nuuumannn]

While going straight to the Beaufighter and skipping the Beaufort sounds easy to do, you're messing with two different concepts and aircraft developed for different roles. The Beaufighter was originally designed to be a derivative of the Beaufort, as it was initially named Beaufort fighter and was designed as a heavy fighter, which was to share some component commonality with the former, but in practise shared little. The RAF didn't initially need the Beaufighter as a torpedo bomber; it already had the Beaufort! I guess it's like putting the chicken before the egg. Also, the Beaufort had much of Barnwell's input, whereas the Beaufighter was largely Frise and Fedden, mainly because Barnwell killed himself flying one of his own creations - apparently he wasn't a very good pilot.

Another thing, like SR stated, issues with the Hercules are going to hinder any attempt to build an aeroplane powered by it, although you could go straight to Beaufighter II with Merlins as Tomo suggested, with its evil handling and complaints from its pilots, along with high accident rate.

 

[parsifal]

Theres a lot of merit in what you say, but I am a bit doubtful as to the need for the hercules in the first place. Whilst in Australia the first home designed and built Beafighters and Beaforts were about 4 years later. The DAP Beaforts were built with Twin Wasps, but were delayed by the promise of the Taurus, which never materialised for us. We had been negotiating for the production of the twin wasp as a follow on for the R1340 already in production, but we were talked out of. For the Australian built Beafighters, we had planned in 1941 to build the R2600 under licence. They were tested, and were successful and the Americans very keen to set up licence production, but we did not proceed, because supplies of the hercules were promised, and once again we accepted what we were told on face value. But the British supplied Hercs were only available as a trickle until 1944, which greatly restricted the production of DAP Beafighters to about 350. We could have built more than twice that number if the engines were in better supply. The DAPs experiences with the Taurus and the Hercules and the Hercules were major reasons why we insisted on building the Merlin and the Griffon ourselves they were both powered by the twin wasp.

The upshot of all this is that the Brits, rather than hang around waiting for dubious engines to arrive, should instead have swallowed their pride and adapted the beafort to the R1830, and somewhat later, the Beafighter to the R2600. this would have seen the Beafort from about 1938, and the Beafighter from about mid 1939 i think....

 

[Shortround6]

A bit too optimistic in timing, The Beaufort was ordered, like a number of other British of the time, "off the drawing board" in 1936 but the first "production" Plane "L4441" (actually first prototype) didn't fly until Oct 1938 while the rest of the planes on the "production"line waited for flight tests to be completed and see what modifications might or might not be needed. L4441 was finally delivered to No 22 Squadron in Nov 1939 upon completion of testing for initial familiarization of pilots while they waited 2 months for first true production aircraft. First operational flights were in May of 1940 and the problems with the Taurus really began to show up. British fly their first twin wasp powered plan in Aug of 1941 ( work started when?) Australians fly their first Australian-assembled Beaufort A9-1 on 5 May 1941 with the first Australian-built aircraft A9-7 coming off the production line in August.

R-2600 production in 1939 was 163 engines, 140 of them in the last 4 months (Sept being the first month to exceed 8 engines in one month).

 

[tomo pauk]

Beaufighter was tested with R-2600 engines, in second half of ww2, though.
Unless there is an early effort to license produce them in Australia or elsewhere, the historic US demand will make them as good as unavailable for the Aussies/CW. Every A-20 needed 2, so did the B-25. Avenger is an important 'costumer', too.

 

[parsifal]

A bit too optimistic in timing, The Beaufort was ordered, like a number of other British of the time, "off the drawing board" in 1936 but the first "production" Plane "L4441" (actually first prototype) didn't fly until Oct 1938 while the rest of the planes on the "production"line waited for flight tests to be completed and see what modifications might or might not be needed. L4441 was finally delivered to No 22 Squadron in Nov 1939 upon completion of testing for initial familiarization of pilots while they waited 2 months for first true production aircraft. First operational flights were in May of 1940 and the problems with the Taurus really began to show up. British fly their first twin wasp powered plan in Aug of 1941 ( work started when?) Australians fly their first Australian-assembled Beaufort A9-1 on 5 May 1941 with the first Australian-built aircraft A9-7 coming off the production line in August.

R-2600 production in 1939 was 163 engines, 140 of them in the last 4 months (Sept being the first month to exceed 8 engines in one month).

Austraians were tooling up for Beafort production from October 1939. they were promised delivery of the jigs for the taurus by the end of the year, but this was delayed until firstly April then June '40. in November '39, Wackett proposed switching to the twin wasp, but was overulled by his political master when the foreign office assured them that deliveries would occur within 3 months of the previous deadlines ( in fact Wackett had proposed Twin Wasp production from 1938, but it was soundly vetoed by the Foreign Office and as a result our govt acquiesced). this never transpired, for some fairly sound reasons I might add, but that doesnt excuse the brits for lying about what they could achieve. April dragged on to June 1940, and still no delivery of Taurus engines. At that point (fall of france), the air mnistry decided to slap an export ban on the export of engines and associated techs. Good reasons for that as well, but tough luck for us. Then, wackett repeated something he had been advocating since 1938. because they were more reliable as suppliers, we should switch to R1830 production. Further, Wackett and his design team calculated that conversion of the Beafort to take the replacement engine was a relatively simple excercise. Brits were aginst that as well, citing that it was technically not possible, or beyond the Australian capability to do such a conversion. Finally in 1941 we had had enough and in April a Beafort was test flown with a twin wasp, which I think had by then entered production in aus. There were problems, which delayed final clearance for production to September or Novemeber (I forget).

The point from all that is that the twin Wasp Powered version of the Beafort could have flown from 1940, but was delayed until the end of 1941, for not good reason.

I think if work on the taurus had been abandoned, in favour of setting up a licence production of the Twin Wasp, both the Australian and Bristol production of the beafort would have been greatly improved. In my opinion the Taurus was an engine fraught with problems, and significantly retarded the delivery dates for the Beafort. pride goit in the way of common sense in my opinion

 

[parsifal]

duplicate post, sorry

 

[parsifal]

Beaufighter was tested with R-2600 engines, in second half of ww2, though.
Unless there is an early effort to license produce them in Australia or elsewhere, the historic US demand will make them as good as unavailable for the Aussies/CW. Every A-20 needed 2, so did the B-25. Avenger is an important 'costumer', too.

Thats true, and Befighter delivery from Australian suppliers was also delayed until around that time, because of a number of problems, the most important of which was the failure to supply enough Hercules from England. That engine drought all of a sudden and miraculaously changed, when Wackett once again suggested we produce the R2600 and use it instead of the hercules. This was something he had advocated almost from the beginning of the Beafighter program.

Wackett was canny. He seemed to know ther were inherent problems for the AQustralians to rely on British engine suppliers. And our aircraft deliveries did take a big hit because we chose to rely on the unreliable

 

[merlin]

So I wonder how much it might have been if the 'twin-wasp' option was accepted in 1938 !?

 

[Shortround6]

So I wonder how much it might have been if the 'twin-wasp' option was accepted in 1938 !?

Not much change except the planes produced in in England in 1940 and early 1941 would have had better engines. But not enough better to change the Performance by much.

 

[parsifal]

Not much change except the planes produced in in England in 1940 and early 1941 would have had better engines. But not enough better to change the Performance by much.

Timewise probably not much difference, but operationally the Taurus, despite its great promise, was a major drag chute on Beafort effectiveness, mostly because of reliability issues. Even the RAF acknowledged that they would have been far better off to power the Befort with a twin Wasp installation, simply on the basis of reliability

There were good aspects to the Taurus, but it was fatally flawed as an engine IMO. Taurus was a sleeve valve design, resulting in an uncluttered exterior and very low mechanical noise. It offered high power with a relatively low weight, starting from 1,015 hp (760 kW) in the earliest versions. It was also compact, with a diameter of 46 inches (1170 mm) which made it attractive to fighter designers. Unfortunately, the engine has also been described as "notoriously troublesome", with protracted development and a slow growth in rated power. After several years of development, power had been increased from 1,015 hp (760 kW) to only 1,130 hp (840 kW). As the most important applications of this engine were in aircraft that flew at low altitude, engine development efforts focussed on low-altitude performance.

The first Taurus engines were delivered just before World War II began and found some use primarily in the Fairey Albacore and Bristol's own Beaufort torpedo bomber. Starting from April 1940, it was suggested to replace the Taurus engines of the latter by the famous Pratt Whitney R-1830 Twin Wasp 9in England and somewhat earlier in Australia), but this change was vetoed by the air ministry or at least postponed to the autumn of 1941 while attempts were made to cure the reliability problems of the Taurus, and later had to be temporarily reversed because of shortages of Twin Wasp engines. The Twin Wasp was, however, strongly preferred by both the RAF and the RAAF, especially for overseas postings, because of its much greater reliability. In later models of the Taurus engine the reliability problems were mostly cured by a change in the cylinder manufacturing process, although the engine kept a poor reputation, and in the Albacore the Taurus engine was retained until the end of that aircraft's production in 1943.

There were no other operational applications of the Taurus engine, because its initial reliability problems discouraged the development of Taurus-powered aircraft, and because later-war combat aircraft demanded more powerful engines. Its production lines were closed down in favour of the Hercules engine, but this engine had its own set of issues to contend with .