[AR] Re: BFR Noise
- From: Henry Spencer <hspencer@xxxxxxxxxxxxx>
- To: arocket@xxxxxxxxxxxxx
- Date: Fri, 30 Sep 2016 19:03:55 -0400 (EDT)
On Fri, 30 Sep 2016, qbert@xxxxxxxxxxxxxxx wrote:
I wouldn't think that any rocket carrying people is going to be going
fast enough low enough to make sonic booms an issue, that's if you could
even hear one with all the noise the back end will be creating. And a
more vertical trajectory makes the chance of a hearing a sonic boom even
less.
The big problem is not the ascent, but the *return*, when the thing is
pushing a big loud shock wave ahead of it, straight at the coast. That
shock wave doesn't disappear when the vehicle drops below Mach 1 -- it
just separates from the vehicle and keeps going, although it starts
gradually losing strength when there's nothing pushing it any more.
Concorde decelerated well offshore, but depending on atmospheric
conditions, nevertheless sometimes boomed the coast, for the same reason.
Henry
Other related posts:
