Me-262, NOT Bell X-1 Broke SB First

"Dudley Henriques" wrote in message
link.net...

Even Chilton couldn't say for sure. It's ironic, but of the few who were
in
on it, a civilian named Millie Palmer would have been the best shot at a
certainty. Welch had told her to listen for the booms and she heard them.
Also, Welch not claiming he was first is absolutely within the context of
his personality as well as the extremely "unusual" circumstances that were
directly involved with his prototype flights in the 86 during the week
prior
to Yeager's flight.

Curious, the "booms" (I note the plural form) were anticipated before
anyone flew Mach 1+?
While I suppose they would be predictable, I'ld be kind of surprised
that anyone had. Was there experience with unmanned missiles or
projectiles to showed it?