Back in February International Autograph Auctions held a sale in which a selection of Princess Diana's letters were sold - though the top lot was actually an E H Shepard drawing of Winnie the Pooh and Piglet with Punch, closely followed by an Oliver Cromwell signature.
Now another sale is looming, and this time the world class auctioneers is intending to focus on aviation in particular.
This week sees the consignment deadline for the sale, which will take place on June 12-13. This has already been moved from May 23, and there is just enough time for anyone wishing to sell their Amelia Earhart, Orville Wright or Charles Lindbergh signature to get in touch before the end of this week.
At the moment, the top lot of that section is a military one rather than a pioneer: a very rare signed photo of famous WWI German fighter pilot Baron von Richthofen - better known as The Red Baron - who was credited with 80 victories over Allied warplanes.
The results of his famous dogfights with Snoopy are open to dispute.
Von Richthofen is seen as an unproblematic German war hero untainted with the Nazi years, and the film based on him released in 2008 has helped the lot on offer to a guide price of £3,000-4,000 - indeed this is quite a cautious estimate.
IAA's auction will take place in Heathrow in the UK, and we will bring you more news of it here.
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