I visited Northrop Grumman's San Bernardino facility during the MVAD program to
get familiarized with the NGC and TRW pintle designs early in the program. Up
close, these pintle designs were significantly different than published details
of them. At one point I got to "cuddle" an original, test fired, LMD
(pronounced LEM-DEE) LM descent motors from the engineering archive. The motor
head-end was surprisingly simple but very precisely machined and constructed.
The ablative section was basic and somewhat crude by today's standards. It had
been fired but the documentation didn’t include any details of the test
criteria or duration. Given he amount of char present, it would have been
longer than just a check test or qualification run. I neglected to ask if the
motors were sent to the moon with carbon in them or launched without ever being
fired. Given the design, reliability built in and what would have been involved
in purging them afterwards, I suspect the latter is true. I'll confirm next
time.
Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
http://www.cesaronitech.com/
(941) 360-3100 x101 Sarasota
(905) 887-2370 x222 Toronto
-----Original Message-----
From: arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> On Behalf Of
Henry Spencer
Sent: Monday, July 22, 2019 12:38 PM
To: Arocket List <arocket@xxxxxxxxxxxxx>
Subject: [AR] Re: What happened to the Space Shuttle?
On Mon, 22 Jul 2019, David McMillan wrote:
... The *real* gems in the NASA archives are (IMO) the decades of
experiment and test results, which will generally include the critical
bits of "why we tried this," "what didn't work," "why it didn't work,"
and (hopefully) "this is what *did* work and why."
There's a surprising amount of stuff that works in aerospace
engineering where no one really knows *why* it works -- someone with a
huge R&D budget decades ago just kept throwing spaghetti at the wall
until something stuck, worked out how to duplicate and productionize
it, and then everyone just kept following the recipe (mostly blindly)
for years or decades to come.