STS51L Accident Questions

Derek Lyons wrote:

The data and discussion is fascinating; but the question I started out
this subthread with still stands: Other than an interesting exercise
in data analysis; what's the *point*?



That's completely eluding me also. The failure mode isn't changed by his
hypothesis...whatever that may be.

Pat

wrote:

Isn't it true that you and Catherine


Zata-Jones have been seen together ...

Umm... eww. No. Too skinny.



First Loni Anderson, and now this!
Well, Mr. Lowther, we'll try to get the boys up on Bene Tleilax to cook
up something that will meet your high standards...so when that ghola of
Marilyn Monroe shows up at your door with the chrome steel bedroom eyes
looking at you... ;-)

Pat

On Tue, 08 Mar 2005 20:28:12 +0000, Henry Spencer wrote:

... But the SRB nozzle is recessed a bit into the motor,
so the very bottom of the motor casing is actually below the nozzle inlet,
and liquid slag can (and does) accumulate there. The result, once the
motor has been burning a while, is a pool of liquid which slops over into
the nozzle frequently. Whenever it slops, you get a small pressure spike,
because the liquid momentarily narrows the gas flow path a bit.

So this is continous? I thought it was only a
startup problem...

--
Chuck Stewart
"Anime-style catgirls: Threat? Menace? Or just studying algebra?"

As Scott pointed out the slag is primarily
a startup problem.

I pointed out no such thing. Slag is a constant and never-ending
problem throughout the burn of the motor. Henry was correct in pointing
out the aluminum oxide component of it; strictly speakign it's a mix of
burned and unburned aluminum. Makes for some neato desktop display
pieces (a co-worker has some aluminum "bubbles"), but it's also a sign
of incomplete combustion. Slag issues are different between horizontal
and vertical firings as well.

So this is continous?

Yup. So long as there's aluminum in the propellant, there's slag.

There's a
pretty big hole in the RH SRB, and a massive performance shortfall in
the same.

Neither of which would ahve been catastrophic for the crew of a CEV
launcher. Mission coudl well have been over (maybe they could have made
it to orbit, maybe not), but those issues were not deadly. In fact, the
performance shortfall woudl have *improved* the chances of escape.

Daniel still won't come clean on exactly what he's trying to
illustrate here

I admit to some mystification as well. I see, so far, only two
interestign things in the data: the goofy presentation format which, it
turns out, is partly due to Daniel's tinkering, and the performance
dropoff seen aroudn 59 seconds in the right-hand booster. That
performance dropoff is interesting in its own right, but is easily
explained by the fact there was a honkin' big hole in the side of the
motor. If someone was sufficiently interested (and that someone is not
me), they could use the data to determine the growth rate of the hole,
factor the growing extra port area into motor pressure, predict a *new*
theoretical performance prediction of the motor, and then try to figure
out what effect that performance change woudl have on the Shuttle, in
particular what gimbal angles woudl be required of the two SRM nozzles
and the SSME's to keep the shuttle pointed into the air, and then
figure out at what point in time the maximum gimbal angles are reached
- and consequently the theoretical maximum lifetime of the Shuttle.

This has, I'm sure, already been done. A co-worker recently worked on a
study of thrust imbalance assuming various horrible things happening to
the nozzle; the data was sent to NASA, who then turned it around into
neato CG animations showing the Shuttle stack going nuts.

"Pat Flannery" wrote in message
...


Derek Lyons wrote:

The data and discussion is fascinating; but the question I started out
this subthread with still stands: Other than an interesting exercise
in data analysis; what's the *point*?


That's completely eluding me also. The failure mode isn't changed by his
hypothesis...whatever that may be.

Pat

I am not nor have I ever professed to be a
rocket/scientist/chemist/aerospace engineer
(or even a combination of some of them such as Herb) but I did take a
temporary start up assignment
at Grumman in which I was cleared to work there in a sensitive capacity in
2003 (verify it if you like)
and left under great conditions for a better assignment.

So does that count enough for a laymen's question here that is on topic?

It's a simple question that Herb alluded to but Daniel glossed over. Go back
to March 6th if you wish.

It is also readily available free reading in the Roger's Report and I assume
everyone has read that?

The ice team (or whatever they are technically called, I am an Investigator
not an Engineer) found
lots of ice on the left booster. Am I wrong there? I have even seen pictures
of the ice and the team.

Even I know my right hand from my left so Herb, where was the water coming
from if the air was
so dry? Are you (Herb) discussing smoke coming from the left, or the right
on your March 6th post?

Paul Maxson

On 8 Mar 2005 14:14:46 -0800, wrote:

This has, I'm sure, already been done. A co-worker recently worked on a
study of thrust imbalance assuming various horrible things happening to
the nozzle; the data was sent to NASA, who then turned it around into
neato CG animations showing the Shuttle stack going nuts.

....And if you're not sharing copies of this, I'm gonna send LaToilet
over to your place with a bottle of Cold Duck and wearing nothing but
a pink neglige'.

OM

--

"No ******* ever won a war by dying for | http://www.io.com/~o_m
his country. He won it by making the other | Sergeant-At-Arms
poor dumb ******* die for his country." | Human O-Ring Society

- General George S. Patton, Jr

Chuck Stewart wrote:

So this is continous? I thought it was only a
startup problem...




How would you like to design a nozzle gimbal seal that has to work while
getting sloshed in molten aluminum?
That must be fun.
You know, Rusty may know the location of every space-related PDF in
existence, but a PDF of everything Henry knows would take a whole tree's
worth of paper to print out.

Pat