AHC: Peerless Air Ministry
- Thread starter perfectgeneral
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For Historical reasons I an currently going with the Alvis/Ghome Rone link up but would remind everyone that the Alvis engine is not a strait licence copy of the 14K Mistral Major but like the Pelides is closer to a 2 valve per cylinder version of the 14N series engine.
As to Naval aircraft I will only touch lightly on those but yes as previously mentioned LRMP aircraft will make an appearance I promise.
As to Naval aircraft I will only touch lightly on those but yes as previously mentioned LRMP aircraft will make an appearance I promise.
Ninety one kilos of gun firing ninety rounds per minute from five round clips? Could we not have a belt fed 25.4mm Bren that offers more for less weight? At this time the international standard inch does not exist, so 25.4mm is not yet an inch (but it will be!)Also one possible suggestion for Sir Phillip, invetigate the COW Gun - https://en.wikipedia.org/wiki/COW_37_mm_gun - The weapon might find use on any planned attack/heavy fighter aircraft or light bombers in a potential ground attack role. We are aware that the Americans are investigating the use of such a weapon in their own aircraft and as an anti-bomber weapon it could be utterly devastating. Its deployment on patrol craft like the Blackburn Perth has proven the weapons reliability and usefulness as it can engage both air and sea targets.
And a great updateBut might it be possible to give links or names etc of the aircraft designs, its a bit of a bugger to find them with just the numbers.
https://en.wikipedia.org/wiki/List_of_Air_Ministry_specifications
Although wiki usually only lists the successful bidder, the prototype names might yield more on a broader search.
I notice that the Bristol Draco used four and five cylinder fuel injection. Might an 18 cylinder version with two nine cylinder (three six cylinder?) injectors be a simpler proposition? Call it the Dragon. Centrifugal turbine two stage supercharged air intakes would really have it breathing fire. Up to 12x atmospheric pressure. Jet research shows that companies should be advancing their turbine capabilities anyway.
http://www.enginehistory.org/Accessories/HxFuelSys/FuelSysHx10.shtml
Feddon didn't see immediate improvement in the Draco. Not going the sleeve valve route might give him a nudge to follow up.
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The faster the Taurus is forgotten, the better. Merlin's production was never a bottleneck, it was mass produced from 4 factories (3 or RR, one of Ford) before Taurus went to 100 produced examples. Production of the Jumo 211 and DB 601 combined lagged behind the Merlin production just in the UK. The Pegasus offers a 1000 HP power in 1938, it was 200 lbs lighter than Taurus, wile having no reliability problems. Cancelling the Taurus early can also improve the Hercules' timetable.
The Taurus was important to aircraft designers due to it's low frontal area with a dimeter of 46.25 inches against the Pegasus with a diameter of 55.3 inches. that is as an increase in frontal area of around 1.4 times for the Pegasus which is one hell of a lot of extra drag. Also IIRC the Pegasus was not getting a peak power of 1000hp until quite late in WW@ when it was fitted with a two stage supercharger and was using 100 octane fuel. The Taurus was promising designers in 1936/37 1050Hp on 87 octane petrol a very different kettle of fish.
My technical knowlege about the UK's aero-engine industry is very limited, i'm basically saying 'go with the Taurus' because its there now and is available now. Better to have something than to wait for somehting to come out that could very well have problems or delays. Perfect is the enemy of the good. The Taurus isn't great but its good, the Peggy is perfect, but isn't available now and the UK needs to start rearming now.
Two points to consider here - in WW1 the Bristol fighter was a success, but it had a big powerful engine in comparison with the competing s/s fighters. Yet memories of a successful two-seat fighter spawned the Hawker Demon of the thirties. The other angle to bear in mind, were the doubts that pilots of the time could handle the work load of aircraft as the speeds increased - hence the thought better he just concentrate on flying, and let the gunner take care of the rest.
But once the Defiant was in service it didn't take long for doubts to appear, only surprising there weren't acted upon earlier... The Roc - who ever gave the go ahead for that needs shooting!
Basically I agree - seems quite plausible that when the spec. for the canon fighter was issued, Gloster was asked for a 'back-up' using as a bass the twin design for a turret fighter - but with 2 x 20mm canon & 4 x 0.303"mgs in the nose. It would have been a versatile aircraft - Mk 1 with Mercury, Mk II with Alvis. Gives the RAF a better 'heavy-fighter' than the Blenheim 1F ever could be, and just big enough to convert to night-fighter use.
Aircraft can't however do any ASR, Sunderlands and Catalinas many a time they landed on the water to rescue sailors stranded in life-boats. I would go with Shorts doing earlier work on the 'G' Class Flying boat - which would give much longer coverage than the Sundrland could provide.
In another TL I used the Taurus as an Engine for the Fleet Air Arm, as an example of something the RAF didn't want, and hence was available, and as a misguided Ministry attempt at "Standardisation"!
Fitted to a Single Seat fighter, a navalised version of the Gloster F5/34, and to upgrade the Skua, to give the FAA a competitive Dive-Bomber. It was already the power-plant of the Albacore.
I am going for a compromise between the two, Having the 1050hp Alvis Pelides available whilst the problems with the Taurus gets sorted as OTL.
If frontal area is that important, Rolls Royce makes a nifty V12 engine, called PV12, but better known as 'Merlin'. In production and in service by 1937.
Pegasus (along with other Bristol piston engines) never got a two stage superchager. For those fine feats of engineering, look (again) at Rolls Royce in the UK, though winter of 1941/42 might be a bit too late for this. Pegasus was making 1000 HP already by 1938 - link. Making, not promissing. On 87 oct fuel.
What Bristol promissed was not what they delivered with Taurus. Yes, it featured a small frontal area (good for a fighter, next to irelevant to a bomber - see Douglas SBD), but also a reliability so low that 1st Albacores and Beauforts were deemed problematic for over-water flights, and Air Ministry was shopping at P&W for Twin Wasps to improve the situation for the Beauforts. Supercharger - geared for 5000 ft rated height - will not shine for fighter duties, while Pegasus is available with 2-speed supercharger, again already in 1938.
On 100 oct fuel, the later marks of Taurus gained 70 HP. Merlin gained 300, in 1939, factory aprooved, reliable.
You can reduce frontal area by reducing the piston stroke (how far it cycles out from the crank to the head). A shorter stroke also means a shorter connecting rod from crank to piston. A quick look at the P&W Wasp and Wasp junior shows this well. The Pegasus has a far from "square" 7.5in stroke compared it's 5.75in bore. Take that back to even 5.5in stroke and you could have a sub 50in diameter engine. The swept volume you lose can be more than recouped with the second row of radiating cylinders. 9 x 2in verses 9 x 5.5in of stroke.
However why not just make a poppet valve 2x7 cylinder (of 5 in bore and 5.75 in stroke) Taurus engine?
Proposals for development:
N(cylinders), Bore, Stroke
Taurus (poppet) development line
(14, 5.1875, 5.1875 Twin Wasp Junior)
(14, 5, 5.625 Taurus)
14, 5, 5.75 (just bigger stroke than a Taurus)
14, 5, 6
18, 5, 6 (or give up on the five inch piston)
18, 5, 6.5 (likely development maximum)
I'd suggest that some company licence builds the 5.5in x 5.5in twin wasp, but...
Pegasus development line:
9, 5,75, 7.5 (Pegasus)
14, 5.75, 5.5 (like R-2000 Twin Wasp)
14, 5.75, 6
14, 5.75, 6.5 (poppet Hercules)
14, 5.75, 7
28, 5.75, 6.5 (Atlas - Double Hercules)
28, 5.75, 6 (like Wasp Major)
18, 5.75, 5.5
18, 5.75, 6 (like Double Wasp)
18, 5.75, 6.5
18, 5.75, 7 (poppet Centaurus)
The Gnome-Rhône 14K/N/R has the same bore and stroke as a Hercules and was [post-war: SNECMA 28T 1945 3,500hp] put back to back to make a contra-rotating double. So that has potential as a license build. Rather than stick with the Taurus 5inch piston, I'd standardise on the 5.75inch diameter as soon as you can. Bad enough that the Merlin piston is 5.4inch (6in stroke), not even the Twin Wasp's 5.5in. You could have the Air Ministry set 5.75inch as the standard piston, but the Merlin is having troubles enough and the Griffon will be a 6in piston engine. Hmmm...
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Thank You chaps for the sources, they differ a little from the engine time line I had and I will work on it again. The Problem as I see it is an over reliance on a single radial engine manufacturer.
Because Air Ministry in the OTL (and even less ITTL) does not want yet another ~1000 HP engine in late 1930s? Especially a radial engine. Any bit of resource spent on such engine means Hercules gets less resources. I find it curious that people don't want a historical 1375-1400 HP engine for 1939, yet everyone want to burn sterlings on hopeless copies of G&R 14K or the Taurus.
1475 lbs for 1060 HP (take off; 975 HP at 7500 ft) on the Pelides in 1939 - c'mon, people.
Would you be so kind to elaborate a bit about the counter-rotating doubles?
I don't think that any Air Ministry in the world standardized a bore of piston engines. In American experiance, whenver the government tried to do the technical job that engine company was supposed to do, resulting engine failed.
Now that we're at Rolls Royce - axe the Peregrine, Vulture, Exe. Any extra funding that does not go on the Merlin can be used to bring the Griffon earlier to service.
Purchase license for the P&W R-2180A. 1400 HP on 87 oct fuel, before the war, engines were sold to Japan in the mid-1930s.
If you don't mind that air cooled engine is not a radial, Napier Dagger makes 1000 HP before 1939, and in a fighter that cruises at 230-250 mph will be probably better cooled than on a bomber that cruises at 180-200. Frontal area is far smaller than on any usual radial.
The Dagger was a best a problematical engine and never lived up to it's early promises It had over heating and other problems and was deemed incapable of safe operation in the tropics which for the MB2 was a problem as the Specification F4/34 was basically for a tropical service aircraft.
Would substituting the Twin Wasp for the Perseus have solved some of the Botha's problems?
38 Twin Wasp powered Sunderlands on charge in September 1939 instead of the 38 Pegasus powered versions of OTL. That would be nice.
This is why I've mentioned cruising at high speed (= fighter) vs. at low speed (= bomber) = greater amount of airstream might help with cooling? Granted, for tropical use something more reliable should be used, like Merlin, Mercury or Pegasus. I'd try to have Dagger installed in a small fighter (say, size of Bf 109, MC.202 or I-16), or even on Spitfires if those can be churned out in greater numbers early enough*. Spits with clipped wings preferably, the Dagger was a low altitude engine.
Though, the Dagger was still very much a 2nd tier engine the British had in 1930s.
Hopefully Bothas will never be produced? Not like RAF needs another 500+ torpedo bombers waiting the ironclads that will never arrive. Have Blackburn produce a real bomber, Wellington/Hampden/Whitley? Or the Sunderland?
Re. Sunderland - 38 with Twin wasp and 38 with Pegasus in Sept 1938?
*in OTL, early Merlin production was satisfying the needs of Hurricane, Battle, Spitfire, Halifax, Whitley, Henley, Fulmar, Beaufighter...
In all 1,276 Bothas were ordered from Blackburn to be built at Brough and the Dumbarton factory.
The Beaufort and Botha were intended to be a combined Torpedo Bomber General Reconnaissance (T.B.G.R.) aircraft to replace the Anson in Coastal Command and equip several squadrons in the overseas commands. See the above transcripts of Air Ministry documents dated October 1936. Their main job was going to be protecting convoys not sinking ironclads that will never arrive.
Having written that I agree that T.B.G.R. versions of the Hampden and Wellington would have been better than the Beaufort and Botha IMHO. IOTL the Hampden was eventually used as a torpedo bomber and the Wellington was used as a G.R. aircraft. I've been planning to do a post about it. Furthermore Blackburn did build Sunderlands IOTL. I've also been planning a post where more Sunderlands are built including 21 instead of the Saro Lerwick.
Furthermore ordering Hampdens and Wellingtons for the T.B.G.R. role in 1936 would have been less of a technical risk because the prototypes were already flying, whereas the Botha and Beaufort were both "paper planes" ordered using the new "off the drawing board" system. That is production contracts were placed before the prototypes were flown and tested to save time. However, the Air Ministry was well aware that some of these aircraft would fail.
In September 1935 IOTL Handley Page proposed a Hampden torpedo-bomber with a wider fuselage to meet Specification M.15/35 according to the Putmans Handley Page book. This was the predecessor to Specification 10/36 which the Beaufort and Botha were designed to meet.
Then in November 1938 Handley Page proposed a Hampden with a wider fuselage and Merlin XX or Hercules engines. According to the Putnams Handley Page book Tedder said that, "The Air Staff would leap at such a bomber if available immediately, but could not wait 15-18 months before delivery, so they declined the offer; what they wanted as early as possible from Handley Page was plenty of Halifaxes."
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