MILAVIA Forum

Historic Aviation => Warbirds => Topic started by: AVIATOR on July 31, 2009, 08:04:23 AM

Title: 39 litre German engine needed to compete with a 27 litre Merlin.
Post by: AVIATOR on July 31, 2009, 08:04:23 AM
The two main competing fighters in the Battle of Britain.

We have all heard the comparisons over the years of Spitfire v Messerschmidt during the Battle of Britain and how the German plane was just those few mph faster.
What few know is that those few mph more needed a massive fuel injected 39 litre engine to stay ahead of the lighter Spitfire with it's 27 litre engine with a carburettor.

The Spitfire Mk 1 was powered by a single  27 Litre 1,030 hp Rolls-Royce Merlin III twelve-cylinder liquid-cooled engine giving it a top speed of 350 mph at 19000 feet.

The Messerschmitt Me 109E was powered by a single 39 litre 1150 hp Daimler-Benz engine giving it a top speed of 354 mph.

It shows the falling away of performance as you increase the power to weight ratio in an aircraft.
Title: Re: 39 litre German engine needed to compete with a 27 litre Merlin.
Post by: valkyrian on July 31, 2009, 09:20:17 AM
Interesting note Avi. It seems that the lighter Merlin had more "power density" than the German counterpart.

Maybe without the bubble canopy the Spit was equally fast. I don't know about the other parameters like the  thickness to chord ratio of the wings, the propeller aerodynamics and ofcourse the weight.
Title: Re: 39 litre German engine needed to compete with a 27 litre Merlin.
Post by: AVIATOR on July 31, 2009, 10:51:19 AM
It also proves just how good the 'little' Merlin was.
The Me-109 was faster in a dive because of the huge weight forward.
This was made into a science by the P-47 Thunderbolt later in the war by the Americans. Nothing those days could stay with a Thunderbolt in a power dive.