3-4000hp Merlin

[MH434]

If they had merlins with up to 3-4000hp back in the war, I wonder which Spitfire mark they would have used 8)

My bet would be the V, They are less draggier than the later ones and also much lighter.

Today, the v's is problably the best performing spitfires out there.. Less weight and with same power as the IX, the answer should be fairly obvious

Church Spitfire LF V EE606 had an amazing climb rate, over 6500ft'min
Sadly that plane crashed in 89

 

[MH434]

 

[Kurfürst]

If they had merlins with up to 3-4000hp back in the war, I wonder which Spitfire mark they would have used 8)

My bet would be the V, They are less draggier than the later ones and also much lighter.

Yes but if youd simply bolt a 4000 HP Merlin to a Spitfire V airframe, the engine would seize in short order... the Mk Vs radiator capacity was insufficient for it`s own later engine outputs (15-1600 or so HP) - thats why the Mk IXs were draggier; higher output engines have higher lubricant and cooling needs, and both needs to be cooled; a 4000 HP Merlin would probably achieve this output with higher manifold pressures, and above a given value you`ll probably need some sort of intercooling or charge cooling. Both come with some extra weight, and intercoolers also with some drag (they need a radiator). Now extra manifold pressure will also need a bigger supercharger, which, if its not a turbo or operated via a hydraulic coupling, will ultimately raise your fuel consumption levels and decrease range; you`ll need to add fuel tanks or accept a very potent Mk V with an endurance of 15 mins and a range of 100 miles (or something along these lines). You will need also a bigger prop or more prop blades to convert that amazing amount of engine power into useful THRUST - and a larger prop is always heavier.

In short, weight, more weight and increase of drag. There is a reason why the IX and XIV were draggier and weighted so much more. It isn`t just a matter of putting a bigger engine on the airframe.

 

[MH434]

Yes but if youd simply bolt a 4000 HP Merlin to a Spitfire V airframe, the engine would seize in short order... the Mk Vs radiator capacity was insufficient for it`s own later engine outputs (15-1600 or so HP) - thats why the Mk IXs were draggier; higher output engines have higher lubricant and cooling needs, and both needs to be cooled; a 4000 HP Merlin would probably achieve this output with higher manifold pressures, and above a given value you`ll probably need some sort of intercooling or charge cooling. Both come with some extra weight, and intercoolers also with some drag (they need a radiator). Now extra manifold pressure will also need a bigger supercharger, which, if its not a turbo or operated via a hydraulic coupling, will ultimately raise your fuel consumption levels and decrease range; you`ll need to add fuel tanks or accept a very potent Mk V with an endurance of 15 mins and a range of 100 miles (or something along these lines). You will need also a bigger prop or more prop blades to convert that amazing amount of engine power into useful THRUST - and a larger prop is always heavier.

In short, weight, more weight and increase of drag. There is a reason why the IX and XIV were draggier and weighted so much more. It isn`t just a matter of putting a bigger engine on the airframe.

Good post..
Today they wouldn't have big problems cooling a 3000hp merlin in a MK V airframe. The ccoling systems today are far better than back in the war days.
The weight of the aircraft would problably increased a litttle but not much. But still way lighter than a Griffon spit

Thanks for answering Kurfurst8)

 

[pasoleati]

Could you perhaps elaborate how should this installation be cooled in the Mk. V airframe? Perhaps you should study how they are cooled in Reno racers and then think whether that would be a realistic in a fighter that must also have a decent range and be able to fight (=have guns +ammo).

 

[drgondog]

If they had merlins with up to 3-4000hp back in the war, I wonder which Spitfire mark they would have used 8)

My bet would be the V, They are less draggier than the later ones and also much lighter.

Today, the v's is problably the best performing spitfires out there.. Less weight and with same power as the IX, the answer should be fairly obvious

Church Spitfire LF V EE606 had an amazing climb rate, over 6500ft'min
Sadly that plane crashed in 89

Would have required major structural mod for tail, aft fuselage, longerons, engine mounts, etc to accomodate the huge torque increase