(meteorobs) Multiple sonic booms

[Ed Majden]

on 3/19/05 16:18, Terry Richardson at richardsont at cofc.edu wrote:

> Actually the multiple booms from a single object are dependent on shape
> and in particular on having another part of the object projecting into
> the air stream. A round object or nearly round object would have a
> single sonic boom from the shock wave forming in front as it moves
> through the atmosphere. There is no trailing "edge" of any sort to
> produce a second boom..
> 
    Your right of course.  I'm relating my experiance from my old airforce
days in the RCAF/CAF when they tried to explain this to us ground techs. An
aircraft with multiple projections could generate multiple sonic booms but
unless the airframe was a long one you would probably only hear one.  I
experienced my first sonic boom in the early 1950s at an airshow where an
F-86 Sabre broke the sound barrier in a dive.  I guess that ages me eh! ;-)
I have only experienced one fireball sonic boom.  Never saw the actual
fireball as I was in bed.  I want to add a low frequency microphone to my
Sandia All-sky Patrol Camera to record possible fireball booms on the vhs
recorders audio track. Finding a suitable mic has been difficult.  There are
such devices out there but they cost "big" bucks! For example, Bruel & Kiaer
weatherproof microphone type 4184.  Anyone know where I can find a surplus
one "CHEAP" ?????  A donation would be nice!
Ed