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SR-71: Rock Switching Hands

In "The Black Watch: The Men Who Fly America's Secret Spy Planes", Ernest Gann writes (p 18):

Quote:

"Away with the old sextant and chronometer; the same stars that once guided the ancients now tell the Reconnaissance Systems Operators [SR-71 backseaters] to put the rock in his other hand. North is that way."

What is meant by "put the rock in his other hand"?

It's not very clear, but since he's talking about "the ancients", I think he's referring to the lodestone. Prior to the invention of the modern needle-type compass, the lodestone was a lump of magnetised rock which indicated the direction of Magnetic North. The ancients would also have used the stars and a sextant (or more likely a quadrant or an astrolabe at that time).

The SR-71 has an astro-tracker. A photo-electric cell can be locked onto a star and can even continue to track it in quite broad daylight. It's not particularly good at giving a position, but it is a very accurate source of heading - and therefore replaces the compass.

I think that that is what Gann was trying to say - but I agree that his prose is a bit purple in this particular passage. He must have been getting old by the time he wrote this. In general, he's one of the best of aviation writers.