Thursday, September 15, 2005

R J Mitchell

I'm delighted that an American is memorializing R J Mitchell, the creator of the Spitfire to which we Brits owe our liberty. Mitchell epitomizes the Brit strength of design creativity.

Asked by Hermann Goering, his supreme commander, what he needed to win the Battle of Britain, Adolf Galland, the Luftwaffe's leading ace, replied: "Spitfires".

We should also remember the Rolls Royce design team that created the Merlin engine that powered the Spitfire and its cousin the P-51 Mustang, which later hosed the Luftwaffe out of German skies.

The Spitfire and Merlin highlight the different Brit and German strengths. Correlli Barnett in his The Audit of War describes how the Brits began WW2 with a much inferior industrial base to Germany - the Merlin was only manufactured with interchangeable parts after its wartime manufacture was subcontracted to Ford, with its American manufacturing ethos.

Barnett explains that the elliptical wings of the Spitfire made it more costly to manufacture than German opponents, the Me 109 and later FW 190.

Mitchell and the Merlin team of course knew of the manufacturing limitations, so they substituted design genius, getting substantially better performance than the German opposition, and, crucially, building in huge design stretch. Building in stretchability is very hard to do, since the designer has to envision the unpredictable future. However its worth it - a stretchable design minimizes future development costs and allows manufacturing to optimize on long production runs.

So the Brits pitted their superior design creativity against Germany's industrial creativity. A succession of ever-better Spitfires hammered the Germans throughout WW2 and in spite of their lower individual production costs, the Germans lost more planes and pilots and had much higher development costs since they had to produce a succession of planes and engines to fight the Spitfire. Barnett isn't an engineer, so he missed this.

My favorite book on the engineering is Alfred Price's The Spitfire Story - it includes tactical trial reports for all versions, and a fascinating fly-off between a Spitfire and a P-51. An excellent book on the Spitfire and the Brits, Canadians, Americans, Australians, South Africans, Poles, French and New Zealanders that flew it is George Beurling's Malta Spitfire. He describes the lengths the Germans had to go to to protect their bombers towards the end of the siege of Malta:

As (the single Spitfire squadron) got there we spotted the enemy in half light - fifteen bombers and at least eighty fighters.

That's over six times numerical superiority for the attackers - and they still lost. Design creativity wins.