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Someone should tell Messerschmitt that you can't swap Jumo 210s for DB601s in Bf.109/110s. And tell Supermarine that they can't replace a Merlin with a Griffon - Griffon being over 1/3 larger than Merlin while Merlin is only 1/4 larger than Kestrel.Merlins are not an easy swap out, you need a whole new plane so you are quite correct on this.
That was point I was trying to make: Whether you call it Kestrel Mk. XXVI, Mk. 26 or Peregrine (all of which are same engine), the engine was the logical extension of the Kestrel XVI-P, beefed up to take full advantage of 87 octane fuel.In my notes I have the Kestrel Mk XXVI listed as the original designation for the Peregrine engine.
And tell Supermarine that they can't replace a Merlin with a Griffon - Griffon being over 1/3 larger than Merlin while Merlin is only 1/4 larger than Kestrel.
Actually the Merlin was over 30% larger than the Kestrel and went to 40% larger (heavier) very quickly even for single stage single speed engines. Likewise the radiators and oil coolers go up in proportion to the power, not the displacement.Someone should tell Messerschmitt that you can't swap Jumo 210s for DB601s in Bf.109/110s. And tell Supermarine that they can't replace a Merlin with a Griffon - Griffon being over 1/3 larger than Merlin while Merlin is only 1/4 larger than Kestrel.
True but then the 400 version didn't show up until the big block 396-427-454 had been around for a while. In fact the 327-350 used a different height engine block to accommodate the longer stroke cylinders compared to the 265-283. Sticking a "big block" in might fit under the hood but called for a lot of changes to accommodate it as suspensions, and brakes didn't work properly with the heavier engine.Very little from a 400 will bolt into an original 265, but they are all referred to as the same family.
Or to Napier Sabres or RR Nenes. There's no way an aircraft designed to optimize the 960 lb. Kestrel can fit a 1,600+ lb Merlin. You might as well try to sit a P&W R-2800 Double Wasp into a Curtiss P-36.A serious upgrade would have to be to Merlin engines.
To be competitive with two Kestrels I suggest the fighter would need to be smaller and lighter than the Whirlwind, perhaps the size of the de Havilland DH.88 Comet or Grigorovich E-2.a project that looks very much like Whirlwind, has two then-current Kestrels. Is there any merit in the proposal?
It won't look like a mini-Whirlwind, but how about two Kestrels in something like the Fokker D.XXIII?So let's stipulate that RAF issues a spec for a fighter armed with 12 .303s in 1934 (a year earlier than the F.37/35 specification that materialized as Whilry), and that is won by a project that looks very much like Whirlwind, has two then-current Kestrels
4.000" bore blocks have the exact same block height (9.025) as the previous 265-283 blocks, they just have larger bearing journals (2.45 mains/2.10 rods) versus previous (2.30 mains/2.00 rods). 400 blocks (4.125" bore) have same block height, but still larger 2.65" mains. I've built dozens of them, often mixing parts - there were adapters to put older cranks in newer blocks for less bearing friction (in theory).Actually the Merlin was over 30% larger than the Kestrel and went to 40% larger (heavier) very quickly even for single stage single speed engines. Likewise the radiators and oil coolers go up in proportion to the power, not the displacement.
True but then the 400 version didn't show up until the big block 396-427-454 had been around for a while. In fact the 327-350 used a different height engine block to accommodate the longer stroke cylinders compared to the 265-283. Sticking a "big block" in might fit under the hood but called for a lot of changes to accommodate it as suspensions, and brakes didn't work properly with the heavier engine.
I repeat - then how did Messerschmitt do it for the Bf.109/110? Ju.210 was 974lbs, while DB.601 was 1,300+ lbs.There's no way an aircraft designed to optimize the 960 lb. Kestrel can fit a 1,600+ lb Merlin.
To be competitive with two Kestrels I suggest the fighter would need to be smaller and lighter than the Whirlwind, perhaps the size of the de Havilland DH.88 Comet or Grigorovich E-2.
View attachment 660444 View attachment 660451
Replace the Comet's de Havilland Gipsy Six R engines and two-bladed props for liquid cooled Kestrels running three-bladed props, remove the second seat, add armament, radiator and some armour and we have something. But it will be too small for later upgrading to the Merlin, etc. You can see how small the Comet is below.
I repeat - then how did Messerschmitt do it for the Bf.109/110? Ju.210 was 974lbs, while DB.601 was 1,300+ lbs.
And how did Supermarine replace a 1,230lb Merlin II with a >1 ton Griffon 83?
(my bold)Because the 109 was designed with an eye towards larger engines from the first place. The DB600, which is a ~1230 lb (dry) engine, was already running on the bench by 1932 and was ready for aircraft by 1935. The V13 and V14 prototype 109s were fitted with DB 600As and some racing/world record attempt aircraft were fitted with DB 601 prototypes.
With a near total redesign (new wing, new tailplane, new landing gear, new radiator arrangements, revised control arrangements). Along with an absolute shed-load of ad hoc engineering and trails work over the course of nearly four years.
Messerschmitt did a lot for the 109. The 109 with the DB 601 didn't fly until Dec 1937 not counting the two race planes.I repeat - then how did Messerschmitt do it for the Bf.109/110? Ju.210 was 974lbs, while DB.601 was 1,300+ lbs.
The DB 600 was far from "ready for aircraft by 1935" and it wasn't really ready for much of 1936. It was flown in those years but while the Germans considered suitable for bombers in the early years it was not considered suitable for fighters. How fast it could be sorted out was questionable, and lead to a lot of planes using Jumo 210 and Jumo 211 engines. DB couldn't reach production deadlines either.Because the 109 was designed with an eye towards larger engines from the first place. The DB600, which is a ~1230 lb (dry) engine, was already running on the bench by 1932 and was ready for aircraft by 1935.
How much of a total redesign was the Spitfire XII vs. the Spitfire V, apart from obvious engine and cowling change, as well as installation of a bigger cooling system?
However the Spitfire happened to have enough wing and a long enough fuselage and other attributes of size that some of the needed modifications weren't too disruptive.
(my bold)
Do we know for sure that Bf 109 was designed with an eye towards the later engines?
Yep, we do.
The internet just ate my very detailed reply, so broadly:
The DB 600 was already in consideration as a potential powerplant for German fighters by very early 1934. The RLM's fighter development contracts issued in February 1934 specified the Jumo 210 as the powerplant, but there was a provision made for use of the DB 600.
BFW considered not only the Jumo 210, but the (similarly sized) BMW116 and the DB 600 as potential engines during the design stages of the 109 in 1934-1935. At least five of the pre-production prototypes (V 8, V 9 V 10, V 11, V 12 and V 13) all had DB 600s originally fitted or Jumo 210s replaced with DB 600s.
Bowlderising the history, but the 109 was designed to be capable of handling DB 600 series engines from the outset, but had to use the Jumo 210 for a number of years because the engine A) wasn't fully reliable yet, and B) the bombers got more priority for engines than the fighters did.