Talk:Supermarine Spitfire (Griffon-powered variants)

After much deliberation (????), and through popular demand this article has been created and the information taken off the Supermarine Spitfire (late Merlin powered variants). This should give more scope for this article to be worked on and improved. Minorhistorian (talk) 03:22, 17 May 2009 (UTC)

CE

Did a cheeky little CE and noticed that quite a lot of the later material is uncited. Keith-264 (talk) 16:59, 24 May 2017 (UTC)

Top speed?

In the Mk XIV section in first quotes the top speed as "446mph at 25,000ft" in Quill's description of the first flight. Then a paragraph or two later it says "reaching a top speed of 400mph at 5,000ft" when chasing the V1. They can't both be right. I suspect what was meant was that the top speed for low altitude or at 5,000ft was 400mph, but this is not the same as the maximum speed the aircraft can reach at optimal altitude, and it would be odd for a plane like the Mk XIV to reach its maximum speed at only 5,000 ft, after they went through all the trouble of installing a 2-stage supercharger, etc.

64.223.109.18 (talk) 08:16, 28 December 2018 (UTC)

They are both right. The top speed at 5,000ft (phenomenal for the time) was as quoted, and the top speed at 25,000ft was as quoted. Aircraft tend to go faster in thinner air, until the air gets too thin for the engine to breathe and the performance declines. The absolute maximum, for a piston-engined aircraft of the Second World War, will be the maximum at the rated full-throttle altitude (the height at which the automatic boost control, a barometric aneroid, allows the carburettor throttle to open fully -- or, on a German fuel-injected aircraft, the height at which the aneroid delimits the supercharger -- because full power applied any lower than that would result in 'overboost' or excessive inlet-manifold pressure and hence engine damage and quite possibly a loud bang.) That doesn't mean that the aircraft doesn't have an identifiable top speed at a given lower or higher altitude, because obviously it does. A fighter's 'top speed' in practice is only ever the top speed for a given altitude. Khamba Tendal (talk) 20:52, 21 May 2019 (UTC)

Mk XXIV Armament

It says in the article " As a fighter, the F Mk 24 armament consisted of 4 × short-barrelled Mk.5 20 mm Hispano cannon" and then "Late production aircraft were built with the lighter, short-barrelled, electrically fired Mark V Hispano cannon". As you'll have realise I can count in Roman, and I know that Mk. 5 is the same as Mark V... Number774 (talk) 21:10, 17 November 2019 (UTC)