Imhadn't known what happened to the other X-1s. I wonder if @GenChuckYeager flew just the one?https://twitter.com/jerrysreedy1/status/999998100998533120 …
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General - I got this list from Jay Miller's 2001 book 'The X-Planes'. Jay doesn't cite a specific source for that list. Obviously I would like to defer to your first-hand knowledge!
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