Question regarding warbird rarity & value

[Bill Greenwood]

Mark, you are correct that there were other Marks of Spitfires that had a high altitude version. The Mark IX for instance, like mine, when it was originaly built as a single seater fighter was a H F IX. It had a Merlin Model 70 engine, I believe. Top speed was 416 mph at about 25,000 feet and the service ceiling was 43,500 feet. I think the LF Mk was more common, it had a Merlin Model 66, and the top speed was 408 mph at about 16,000 feet?
The only real difference between the Rolls 70, or 76 and the 66, is the gearing of the supercharger and the prop to optimize for the altitude desired. A Rolls 66 is similar to the Packard -7 as used in P-51Ds.
Neither of these Mk IXs were the ultra high altitude version with the extended pointed wing tips. These look sort of funny and were not a real success, not really needed. The H F IX would have the full eliptical wing tips, and the L F version could have either wing, but often with" clipped" wing tips. They aren't actually clipped, but are are just a different bolt on version of the outside couple of feet. I have flown both versions, the shorter one is nimble with a quick roll rate.

[Bill Greenwood]

As for the pure photo recon versions of the Spitfire, I once talked to a RAF pilot who had flown them.
I think the Mark that he was referring to was an XI. And to be correct, it is XI, not 11. The later versions did use regular numbers, thus 24 not XXIV.

They went to Berlin and back to base in England, with penetration of the combat areas at 36,000 feet. This was in a fighter that was mostly unheated and unpressurized.It of course had oxygen and had electric plug ins for heated gloves. The recon versions had less or even no guns but carried more fuel, as much as 257 gal with added wing tanks and a big drop tank. They were clean, the top level speed of an XI, I believe is 422 mph. And they were fast at high altitude. It was pretty hard for a German fighter to get up to them and catch them. If needed the Spit could dive away and virtually nothing was going to catch it, given a head start. In high speed experiments, two Mk XI s were test dived to over .90 Mach. If they were dealing with a jet, not too likely, the Spit could climb if they saw the contrails of the jet in time. The ME 262 was 125 mph faster in level flight, but only had a service ceiling of about 35,000 feet, if I recall, and would be limited by fuel range.
A recon Spit could do two round trip missions in a day, of course not with the same pilot. I don't think it was very healthy for the pilot to spend much time at that altitude, and cold, and it must have worn them down.
The pilots had to be highly trained to get the accurate photos needed, disciplined to avoid combat and do the vital, but less macho job. They did at times come down almost to ground level when the mission called for it, and took the risks there.
These versions of Spitfires were among the best photo recon planes, as was the later Griffon versions.