In article , Jim Kelley wrote:

More importantly, 100 years ago airplanes could not fly.

How far back in time do hot-air balloons go?

It isn't possible for balloons to go back in time. :-)

That depends on whether you happen to have a very long, incredibly
massive cylinder, rotating at near-relativistic speeds, somewhere
downwind of your launch point.

Most of us don't - extreme tidal effects aren't one of the things
exempted by PRB-1.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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