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Old February 4th 07, 10:06 AM posted to alt.binaries.pictures.aviation
Henry_H@Q_cyber.org[_1_]
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Default Need help with a rocket motor ID

On Sun, 04 Feb 2007 03:40:31 GMT, "William R Thompson"
wrote:

Henry_H@Q_wrote:

I see that there was a lot of discussion I didn't read. I am glad to
see that the source was tracked down. But, I am I bit surprised to see
it was from Rocketdyne.


It looks like someone issued specs that said, basically, "make it
reliable and simple, and don't worry too much about the weight."


As I said, it doesn't look like it goes to far "up the stack". I
though about it being an "airplane" but I couldn't imagine which one.

But, it looks better, "all dressed up."

(For airplanes, RATO lost out to the army developed "JATO" solid
propellant "boosters.")


I can see why. RATO could be throttled and restarted, but I think
the only application anyone saw for that was in seaplane take-offs.
JATO looks a lot less maintenance-intense than RATO (see attached
picture).


Hey, looks simple to me! I have done my tour on both the liquid and
solid fronts. Both have advantages, both have problems. I will take
the liquid problems any day. But, I am in the minority it seems.

I think it turns out that rockets are much to expensive for general
use whether they are liguid or solid.

I meant to say that although Truax didn't have the right answer for
airplanes, that work lead drrectly on to the whole world of hypergols
in the US, many, many vehicles and engine/motors.


T-Stoff, was a mixture of 80% hydrogen peroxide plus
oxyquinoline or phosphate as a stabilizer. [most of the other 20
percent would have been water. _hh]

And that

C-Stoff was a mixture of 57% methanol + 30% hydrazine hydrate + 13%
water, with
traces of either cupro-potassium cyanide or copper oxide (probably as
a stabilizer).


I accept those as being correct. Methanol the kind of stuff you would
want as a fuel. The hydrazine hydrate would be added to provide
"smooth combustion" and the water may have resulted from using the
highest concentration of hydrazine hydrate that was available, or
possibly it was just added as coolant.


(Usually wiki is a really good place for this kind of stuff, but I
didn't find the exact numbers there)


Those are the same figures in Sutton's "Rocket Propulsion Elements."
I figure that Mano Zeigler gave different numbers in "Rocket Fighter"
due to conditions in Axisland--with the Allies bombing their plants
and supply lines, they may have had to settle for anything that could
flow through the lines and burn.



If I remember the book, and I am pretty sure I do, it was sort of a
"quick and dirty" account based on very limited sources. I think I
first read it myself only a couple of years after the war, so it has
been around a while. A lot of documentation dhowed up later that the
author didn't have then.


It is hard to find people in the rocket biz that have had long term
exposure to hydrazine that have not also be exposed to N2O4 so when
there are stories about long term effects, you don't know which to
blame. But I will take the alternative to "in a couple of more days,
they die." Better chronic than prompt.


As I recall, Vance Brand passed out from exposure to dumped fuels
during the Apollo-18/ASTP descent, and the crew was taken to the
hospital afterward. They didn't seem to suffer any long-term effects.



I remember somethign about tat, but I don't even know as much as you
said.

(In ordnance circles, I got into this thing of distinguishing between
"high order" explosions or "detonations" and "low order" explosions or
deflagrations. Then there are "no yield" ones, like tank ruptures. I
use to rankle when people talked about auto gas tanks exploding, or
example. Then I read some dictionaries. The "sufficient" definition of
an "explosion" seems to be some event in which a noise was heard.)


I know people who think that a proper footnote is anything with
an asterisk. (Sorry, but citing a newspaper gossip column isn't
quite the same as citing, say, a trial transcript.)

One thing that was more hazardous on the Me163 than the exotic (for
then) propellants was the operational scenario. Take off, climb to
combat altitude, run out of propellant, glide to a landing spot, and
be stuck on the ground on the landing skids.


The allied pilots quickly figured that out, and that there was little
to be done about powered flight, so they just waited and followed them
down and nailed them on the ground. It is a wonder that anyone had any
stories about explosions, they should have all been killed.


My conclusion from trying to find out what happened was that the
Luffwaffe was totally negligent in keeping any useful accident reports
in the WW II era, at least that I found.


That was a typical condition in the Reich. And, given how hard it was
to find self-confessed Nazis after the war, the condition persisted.
Albert Speer's "Inside the Third Reich" is a classic example.



You have to be careful about testimony of participants. You have to be
ten times more careful when they are under duress. And, being a POW
after having lost a war is a LOT of duress.

But there are all to many examples of people thinking up stories and
then feeding them to people just like that to get them to play them
back.

The worst one I think of off hand was some guy who was on the
interrogation team of the Japanese Navy participants in PH. His own
personal theory was that the Japanese should have left the ships alone
and gone for the oil tanks. So he asked that question over and over
again until all the Japanese got the answer right.

There was a similar deal about the pre war demands, whch are totally
unclear as to whether they mean "China" or IndoChina" or both. Some
different guy (I guess he was different) got all sorts of people to
say it would have been entirely different, "If they had only known"
what we said.

The Japanese were unusually eager to cooperate, be everyone is eager
in those circumstances.

Designers are often told that "You have to listen to what the user
says, they were the ones that know what is going on.

I agree that you should listen. But you should evaluate what you hear.
Anyone's "eye witness account" is likely to be highly biased and
frequently just imaginary.


That's what I was taught when getting my degrees in hysteria, er, history.
My favorite example has to do with the "Nuts!" event at Bastogne.
There are several accounts of exactly what was said; the accounts
come from people who were there--and they don't match up.



I have read many of those accounts. And there are very different
versions of what General McAuliffe initally said. Some say it was
profane, othere say that people heard what they wanted to hear, and
that McAuliffe never used profanity and that is exactly what he would
have said.

"It is very true, and if it is not, it should be."

Some stories are so well known and are so much a paart of what
happened they are as important as "facts."


But, there is another aspect of the "Nuts" story. In about 1950 the
National Archives put togetner an exibition on a train and it toured
the country. It had really "heavy weight" stuff on it. Including the
Constitution and the Declaration of Independnce, the originals (I
think!). Hard to imagine doing that now.


I toured the train. I was there. I SAW the piece of paper that
McAuliffe wrote it on.

Just like the Germans to file that away.

SO, although there can be debate about what he SAID, I KNOW what he
wrote, because I saw it.

However, I can't find any discussionof anyone else knowing that.


(Although the military historian SLA Marshall claims that the
Germans did, indeed, get the "Nuts!" message. Marshall interrogated
Manteuffel and his staff after the war. At one session Manteuffel
kept blaming his mistakes on his staff. At last one of his subordinates
leaned forward, waggled a finger in Manteuffel's face and shouted
"Nuts! Nuts!")



Another sub plot to that story that I have seen in one account was
that there was some junior officere there who was an English language
expert. He thought up the idea of the surrender demand. And wrote it
and got permission to deliver it. But, when he got the answer, he
didn't know what it meant.

The officer who escorted him back to the German lines explained it in
terms the German understood. He may have used any of the expressins
that have been suggested.

It was also said that when they parted, the German made a last plea
"you must accept or many people will die." the escort was said to have
said "this is war and that is what it is all about. Many will die and
they won't all be on our side."

Now, that is a REAL fairy tale.


And, what were the seals and all the other bits made of. I was once
reading a report on the X-1 which was very like an American Lox Me163
and at about the same time. There was something about an explosion and
a fire. The report said they weren't sure what happened, but they
though it might have involved a seal. (I think maybe it was in a check
valve and lit off when the valve closure slammed on it.) They then
started to discuss what sort of special, proprietary LEATHER (!) the
seal was made of. I quit reading.


The Ulmer leather gaskets, which if memory serves were treated with
tricresyl phosphate. The accounts I've read said that the treated gaskets
didn't react with the liquid oxygen--but in the presence of lox, the gaskets
became *very* sensitive to mechanical shock, making them "slightly"
explosive. I think the losses of the X-1A, X-1D and second X-2 were
blamed on that.



I have though about that a lot. The correct process for making leather
LOX compatable doesn't leave ANY leather in the leather. Or as I told
a guy once "Send me that (polyethelyne bottle) to be LOX cleaned and
I will send you back an empty bag with a tag on it."

In those days, I gather, they hadn't come up with impact testing. And
such events were how they got the idea.

In one sense, most things are "compatible" with LOX, as there is no
"attack' in the absece of impact.

RP won't react with LOX until you hit or subect it to an ignition
source. That is what makes it so dangerous, you can get an
accumulationt that will blow the back end of the vehicle into the next
county. "Static" compatibility is meaningless for LOX.

"Low order" reactions to impact are also pretty meaningless since even
a small pop can do a lot of damage, including possibly stuff like
igniting some surrounding stuff, like aluminum valve housings, say.

It is somewhat hard to see how anything could have been done wiht any
useful oxidizer, LOX, peroxide, N2O4 or whatever, untel Teflon came
along. But they did do lots of stuff. Even Teflon has a lot of
problems. (but is compatable.)


Henry H.

--Bill Thompson