Absolutely preaching to this choir. You think 'they' would of leaned
'their' lesson, but then the SLS comes to mind.
May be cancelled before a manned mission anyway, or sooner. My hat off to
SpaceX who,in my opinion, has earned the "man rating" privilege
especially with the rung out LES.
On Thu, Mar 26, 2020 at 4:09 PM Anthony Cesaroni <anthony@xxxxxxxxxxx>
wrote:
Humans really shouldn’t be put on top of solid rockets unless absolutely
necessary. Liquid propulsion is bad enough. Just say’n.
Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
http://www.cesaronitech.com/
(941) 360-3100 x101 Sarasota
(905) 887-2370 x222 Toronto
*From:* arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> *On
Behalf Of *roxanna Mason
*Sent:* Thursday, March 26, 2020 6:58 PM
*To:* arocket@xxxxxxxxxxxxx
*Subject:* [AR] Re: Valley Tech throttleable restartable solids (!)
it turned out that shutdown
transient loads would be too high for the orbiter and ET structures.
Did not know this was ever a consideration.
So instead of shelving SRB's for liquid boosters they rolled the dice.
Another example of politics over engineering.
On Thu, Mar 26, 2020 at 3:48 PM Henry Spencer <hspencer@xxxxxxxxxxxxx>
wrote:
On Thu, 26 Mar 2020, Uwe Klein wrote:
<restartable rocket>
So the quenching depends on depressurizing the chamber.
Is this "reliable"? at all | below the described altitude?
If it's done right, with attention to dP/dt and how the propellant
responds to it, it's reliable. This is fairly standard technology for
solid-fuel ballistic missiles, although they typically use pyro charges
that blow open vent ports, because they don't need to do restarts.
(Disregard post-Challenger comments about how solids "can't be shut down",
which come from people not very familiar with either the technology or the
history. In fact, solids were chosen for the Shuttle boosters on the
*explicit* assumption that they *could* be shut down in an emergency, via
vent ports; unfortunately, once that choice was made, it was cast in
concrete, and could not be reconsidered when it turned out that shutdown
transient loads would be too high for the orbiter and ET structures.)
Henry