Gloster F.9/37
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Shortround6
Major General
The Wiki weight is for a very early R-1830. The 1940 versions with 1100-1200hp for take-off single stage were around 1460lbs with 2 speed drive for the supercharger.
It might work, although further British options were initially proposed when the G.39 was designed and were in fact pursued. Aside from the Taurus, two Kestrels was the other option. Two G.39s were built; L7999 powered by two Tauruses and L8002 with two Peregrines. Top speed of the Taurus aircraft was 360 mph, the Peregrine powered variant was 330 mph. Both were described as being very manoeuvrable and easy to fly, apparently.
Indeed.That weight seem to be 160 lbs greater than for Taurus II (dry weight).
Should not be such a major issue with aircraft as big as F.9/37, with some of items relocated further aft (like radio, battery, oxygen bottles?)? Or, with placing a second crew member aft the CoG?
Shortround6
Major General
I am not sure what you really gain?
The Engines that drove the prototype at 360mph were never production engines and disappeared rather quickly and completely? Horsepower ratings of the early Taurus engines seem to be a bit confusing especially when trying to relate them to the Performance of the F.9/37.
Th Original engines in the F.9/37 were supposed to be 1050hp T-S(a) engines with the altitude not given. They were replaced in the second prototype by Taurus III or " 900 hp Taurus T-S(a)-III" .
A problem is that Lumsden doesn't list or use the T-S(a) designation and starts with the MK II model which gives 1060hp for take-off 3100rpm/+4.25lbs boost.---930hp at 4000ft/2700rpm/+2.75lbs continuous (climb) and 1110hp at 4,000ft/3100rpm/+4.25lb 5 min emergency rating.
The MK III engine (which he claims is for Australian Beauforts ?) is listed at 935hp for take-off 3300rpm/+4.5lbs boost.---900hp at 14000ft/2800rpm/+2.5lbs continuous (climb) and 1060hp at 14,500ft/3300rpm/+4.5lb 5 min emergency rating.
The MK VI, XII, and XVI Taurus engines are pretty much 1085hp for take-off 3100rpm/+4.75lbs boost.---985hp at 3750ft/2800rpm/+3.75lbs continuous (climb) and 1130hp at 3500ft/3100rpm/+4.75lb 5 min emergency rating on 100/130 fuel.
Given that the Prototype aircraft was supposed to do 360mph at 15,000ft with 1050hp T-S(a) engines and only 332mph with the " 900 hp Taurus T-S(a)-III" something is not making sense.
The Engines that drove the prototype at 360mph were never production engines and disappeared rather quickly and completely? Horsepower ratings of the early Taurus engines seem to be a bit confusing especially when trying to relate them to the Performance of the F.9/37.
Th Original engines in the F.9/37 were supposed to be 1050hp T-S(a) engines with the altitude not given. They were replaced in the second prototype by Taurus III or " 900 hp Taurus T-S(a)-III" .
A problem is that Lumsden doesn't list or use the T-S(a) designation and starts with the MK II model which gives 1060hp for take-off 3100rpm/+4.25lbs boost.---930hp at 4000ft/2700rpm/+2.75lbs continuous (climb) and 1110hp at 4,000ft/3100rpm/+4.25lb 5 min emergency rating.
The MK III engine (which he claims is for Australian Beauforts ?) is listed at 935hp for take-off 3300rpm/+4.5lbs boost.---900hp at 14000ft/2800rpm/+2.5lbs continuous (climb) and 1060hp at 14,500ft/3300rpm/+4.5lb 5 min emergency rating.
The MK VI, XII, and XVI Taurus engines are pretty much 1085hp for take-off 3100rpm/+4.75lbs boost.---985hp at 3750ft/2800rpm/+3.75lbs continuous (climb) and 1130hp at 3500ft/3100rpm/+4.75lb 5 min emergency rating on 100/130 fuel.
Given that the Prototype aircraft was supposed to do 360mph at 15,000ft with 1050hp T-S(a) engines and only 332mph with the " 900 hp Taurus T-S(a)-III" something is not making sense.
I've asked a similar question a month before, but seems that we'd wait quite a time to have the answer 
Unfortunately, when people lump statements like "1175 HP DB-601", "1030 HP Merlin III", or something similar, other people reading it are bound to draw conclusions that differ from historical data.
Looking at Taurus II and III, the II (along with VI, XII and XVI) seems like a 'bomber engine' - better take off rating, but worse at altitude vs. the III. That one, despite being called as '900 HP Taurus III', offered useful 1060 HP at 14500 ft (with less power down low and for TO, ie. close to that 900 HP mark). At any rate, the Bristol's engines seem to deserve far better book, just about them?
Hopefully, a torpedo bomber that can be a far more survivable than Beaufort; heavy/night fighter torpedo bomber better than Beaufighter; a better fighter than CAC Boomerang? A far better combat aircraft than Blenheim and Maryland? A plane that allows for more Mossies produced as bombers?
Unfortunately, when people lump statements like "1175 HP DB-601", "1030 HP Merlin III", or something similar, other people reading it are bound to draw conclusions that differ from historical data.Looking at Taurus II and III, the II (along with VI, XII and XVI) seems like a 'bomber engine' - better take off rating, but worse at altitude vs. the III. That one, despite being called as '900 HP Taurus III', offered useful 1060 HP at 14500 ft (with less power down low and for TO, ie. close to that 900 HP mark). At any rate, the Bristol's engines seem to deserve far better book, just about them?
Hopefully, a torpedo bomber that can be a far more survivable than Beaufort; heavy/night fighter torpedo bomber better than Beaufighter; a better fighter than CAC Boomerang? A far better combat aircraft than Blenheim and Maryland? A plane that allows for more Mossies produced as bombers?
fastmongrel
1st Sergeant
What about Merlins was the airframe big enough.
Wing areas might give a clue for a size of complete aircraft:
-F.9/37: 386 ft²
-Whirlwind: 250 ft²
for comparison:
-Fw-187: 327.22 ft²
-P-38: 327.5 ft²
-Ta-154: 333.7 ft²
-Ki-45: 344 ft²
data from Wikipedia
Seems like Gloster was quite an aircraft (size-wise), even when compared with other twin-engined fighters. Merlin indeed would not be out of order there, of course if the CoG issues can be reworked without a bigger redesign.
-F.9/37: 386 ft²
-Whirlwind: 250 ft²
for comparison:
-Fw-187: 327.22 ft²
-P-38: 327.5 ft²
-Ta-154: 333.7 ft²
-Ki-45: 344 ft²
data from Wikipedia
Seems like Gloster was quite an aircraft (size-wise), even when compared with other twin-engined fighters. Merlin indeed would not be out of order there, of course if the CoG issues can be reworked without a bigger redesign.
Shortround6
Major General
A YP-38 was about 840-850lbs heavier empty than a Gloster F.9/37 and that is after subtracting the weight of the engine accessories (all of them) and the cooling system weights from the YP-38. The YP-38 had about 60 sq ft less wing area.
The Gloster F.9/37 was also one of those twin engine planes where the engines are about as far forward as they can get.
Yes you can add ballast (often done to Spitfires) but the plane just may have a lighter frame work/structure than a P-38.
The Taurus seems to have had overheating problems and in production versions was optimized not for bombers but torpedo bombers what with full throttle heights of 3500ft.
Trouble is that the single speed 87 octane R-1830s intended for the British Beauforts were good for 1050hp take-off and 1000hp military power at 11500ft. The two speed 100 octane engines used Austrain Beauforts has 1200hp for take off and 1200hp Military at 4900ft and 1050hp at 13100ft military in high gear.
I am not seeing a real big increase in power here.
The Gloster F.9/37 was also one of those twin engine planes where the engines are about as far forward as they can get.
Yes you can add ballast (often done to Spitfires) but the plane just may have a lighter frame work/structure than a P-38.
The Taurus seems to have had overheating problems and in production versions was optimized not for bombers but torpedo bombers what with full throttle heights of 3500ft.
Trouble is that the single speed 87 octane R-1830s intended for the British Beauforts were good for 1050hp take-off and 1000hp military power at 11500ft. The two speed 100 octane engines used Austrain Beauforts has 1200hp for take off and 1200hp Military at 4900ft and 1050hp at 13100ft military in high gear.
I am not seeing a real big increase in power here.
Agreed with your points.
My point was that, if anyone wants to add a better heavier engine to a twin, Gloster should be a far easier airframe to do that, compared with the smallish Whirlwind.
The R-1830 would offer advantages in 3 categories, vs. Taurus. 1st, it would be a more readily available powerplant, in case the Gloster is produced in Australia or/and Canada. 2nd, as you've noted, id was far more reliable engine than Taurus. 3rd, it would offer more power down low (vs. Taurus III), or at altitude (vs. other Taurus marks).
BTW, do you have any data about the Taurus operating on 100/130 PN fuel?
Shortround6
Major General
The later marks of the Taurus were listed in post #6, were on 100/130 fuel. please note that the later Marks were down 200rpm compared to the MK III which may also say something. )r a misprint?
The P&W offers about 115hp more for take-off and 70-75 hp more at around 4000ft although it should offer more at 13,000-15,000 and up but then it weighs more too. It also has a 7.6% more frontal area. It may be more available and more reliable, just don't expect much performance gain.
The P&W offers about 115hp more for take-off and 70-75 hp more at around 4000ft although it should offer more at 13,000-15,000 and up but then it weighs more too. It also has a 7.6% more frontal area. It may be more available and more reliable, just don't expect much performance gain.
Possibly, probably, Tomo, but if you are going to re-engine it, surely uprated Tauruses or an 1830 would make more sense and be more expedient than the redesign required for the fitting of a Merlin, say. In 1940 the G.39 was canned as a project as the Ministry of Aircraft Production decided on only a handful of airframes to continue with - perhaps the G.39 instead of the Whirlwind? A variant was proposed to F.18/37 to which the Typhoon eventually won and Gloster ended up building the Hawker product instead of its own design. In hindsight, the aircraft that spelt the end for the G.39 was the Mosquito. Interestingly it was borne out of a Gloster project for a twin engined turret fighter.
Indeed, thanks.
A reduction in rpm might increase reliability in later engines? We could indeed use the detailed book on the Bristols
Oh, I don't expect big performance gains, maybe 'reverting' to the initial 360 mph plus 5-10 mph; Gloster was neither small, nor with a particularly thin wing. It should surpass the Beaufighter and rest, though.
Only way to up it's performance was to have Merlin aboard; the Merlin 45 maybe (not too heavy, but with good power between 10 and 20000 ft). Radiators located perhaps akin to Ro.58 (under the aft part of the wing, between nacelle and fuselage; similar to Bf-109), or like at Bf-110 with DBs (outboard of the nacelle, behind the main spar), in order to cater for CoG?
Hello, nuuumannn,
It all depends what you want to do with the up-rated F.9/37. If we have a night-fighter version in production (either with Merlin or R-1830), then DH can build more bomber Mosquitoes. If one wants to use it as a fighter-bomber, or/and a torpedo bombers, than installing the R-1830 should do the trick. Though I'd rather have Merlins aboard even in this case.
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That's right Tomo; that's one reason why it was discontinued; there was no perceived need for it since the roles it was intended to fulfill were already being carried out and with the arrival of the Mossie into service, projected types were overshadowed in capability. I guess there are a couple of problems with fitting Merlins, the cg issue is probably the biggest, which entails quite a bit of modification, whereas fitting the 1830 would require less without the same cg issues, also the supply of Merlins; what are you taking Merlins from if to fit them to the G.39?
The other issue is maintenance between units; having a single design that can do lots of things like the Mossie could means engineers are trained on common types and spares supply is not as much of an issue as if diffferent types doing similar roles is.
It would have made a pretty formidable twin engined fighter and it's interesting to hypothesise if it would have been better than the Whirlwind. Probably would have been a safer bet from a production point of view, but hindsight is a commodity the MAP didn't have in 1940.
When Gloster worked out that the gross weight of the F.9/37 could be increased from 11,550lbs to 14,500lbs they suggested a Merlin powered version. This met most of the requirements for F.18/40, though with four rather than six cannon.
The DTD gave Gloster the go ahead to convert to convert one of the two F.9/37 prototypes to carry fixed forward firing 20mm cannons, A1 radar and a Browning turret. Having the F.9/37 already flying was expected to give a head start to the project.
By December 1940 it was calculated that having a number of F.18/40s flying, or even a reasonable number of production F.9/37s, would not be possible before the end of 1942. The project was placed on low priority in favour of a night fighter from de Havilland, the Mosquito. The project was finally cancelled on 1st May 1941.
The Gloster F.18/40 (Reaper) had an estimated speed of 390 mph at 22,500 feet. For some flight tests the F.9/37 prototype L8002 was ballasted to represent the second crew member and a partial mock up was built in late 1940, but that's as far as it went.
Unofficially it is suggested that the Air Ministry was keen for Gloster to devote resources for development of jet projects, but that wasn't an official reason for the cancellation of the F.9/37 and F.18/40 projects.
Cheers
Steve
The DTD gave Gloster the go ahead to convert to convert one of the two F.9/37 prototypes to carry fixed forward firing 20mm cannons, A1 radar and a Browning turret. Having the F.9/37 already flying was expected to give a head start to the project.
By December 1940 it was calculated that having a number of F.18/40s flying, or even a reasonable number of production F.9/37s, would not be possible before the end of 1942. The project was placed on low priority in favour of a night fighter from de Havilland, the Mosquito. The project was finally cancelled on 1st May 1941.
The Gloster F.18/40 (Reaper) had an estimated speed of 390 mph at 22,500 feet. For some flight tests the F.9/37 prototype L8002 was ballasted to represent the second crew member and a partial mock up was built in late 1940, but that's as far as it went.
Unofficially it is suggested that the Air Ministry was keen for Gloster to devote resources for development of jet projects, but that wasn't an official reason for the cancellation of the F.9/37 and F.18/40 projects.
Cheers
Steve
Thanks for the feedback, Steve. What mark of Merlin was the F.18/40?
Re. from where to get Merlins: after BoB, the Defiant can be cancelled (instead of 1065 examples, built, say, 500 instead?). More Merlins can be acquired with, gradually, less Hurricanes produced. The Beaufighter can be Hercules-only aircraft.
Re. from where to get Merlins: after BoB, the Defiant can be cancelled (instead of 1065 examples, built, say, 500 instead?). More Merlins can be acquired with, gradually, less Hurricanes produced. The Beaufighter can be Hercules-only aircraft.
The estimated performance was based on Merlin XXs.
I think that the crucial factor in the failure of the F.9/37 to acquire a development or production contract was the delay in repairing the first prototype (L7999) which was badly damaged in a wheels up landing at A&AEE, Martlesham Heath, on 27th July 1939. For a variety of reasons the aircraft didn't return to A&AEE, now at Boscombe Down, until April 1940. This nine month delay meant that by the time the Gloster fighter was estimated to be available in late 1942 it's capabilities had been eclipsed by the de Havilland Mosquito and Bristol Beaufighter. It simply wasn't needed.
It is also a consideration the Gloster's work on jet aircraft had become more important to the Air Ministry by this time.
BTW Nuuumann, the 'G' designation for Gloster designs was never used by Gloster for these aircraft as it didn't exist at the time. It was supposedly (according o Tony Butler) made up by a historian after the war to simplify his classification of the companies aircraft.
Cheers
Steve
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