Techical point. There is no such thing as flight level 700. The controlled airspace system stops at FL600 or 60,000’. Anybody operating above that is “uncontrolled” and can pretty much go wherever they want without talking to anyone. Of course about the only planes that routinely fly that high are the U2, SR7q and Concorde.
Anyone know off the top of their head
when the last time we had a
70k foot volcanic blast?
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