Model Forum / General / Rockets / March 2007

also that last included report about the number of "bombing" made is very
misleading. If we take the report at its word, that these were model rocket
and APCP bombs, then what the heck are Model rocket motors doing included? I
mean don't the BATfe relaize that Questes sells almost 99.x% of all model
rocket motors in this country and that they conatin BP and not APCP? In
addition the ONLY model rocket motors that I am aware of that are sold are
AT/RCS DEFG and as I said above, they are a very small percentage of the
overall model rocket motors sold in this county. Based on the stats provided
it appears 8 APCP model rocket motors may have been used as an
explosive...DUH... that just goes to show how useless APCP model rocket
motors are! well as explosive devices. An they didn't even use the actual
model rocket motors as bombs, they used the APCP in something else no
doubt!.

FINALLY, and most importantly, why even include model rocket motors in the
bombing stats  in the first place? The APCP that the BATFE is trying to
control and license are NOT model rocket motors, they are HPR rocket motors!
Last time I looked 62.5 gram BP AND APCP model rocket motors were both
exempt from BATFE.  SO why  even include any stats that have anything to do
with model rocket motors.  Either the BATFE is so dumb that they can't
differeniate between the two types of rocket motors, or this is a freudian
slip where the BATFE plans on coming after model rocket motors next if they
succeed here against HPR rocket motors.

terry dean
nar 16158

.....hiding out just in case they come looking for me......

They need to use bogus data to make us look bad. If they presented the
truth, their arguments would be dead in the water.

I hope someone goes after everyone involved in this linear burn rate crap
that they tried to pull, and goes after things like professional licenses
and other credentials. None of these people have the knowldge to present
expert testimony in court. What they've done in this case is serious enough
to get any case they've been involved with previously overturned.

I hear that some of this may already be in process...

Well, you go that right.  Frankly, I'm starting to think Dave Shatzer
is that dumb and he signed an affidivit to prove that he is also
technically incompetent.

First, there is no such thing as a linear burn rate or radial burn
rate.   There is just one burn rate and that burn rate is applied to
all burning surfaces.   In those propellant grains testted, the burn
time is controlled by the radial distance since that was the shortest
distance for the flame front to travel.   If the propellant grains had
looked like thin washers, then the shortest distance for the flame
front to travel would have been the axial direction.  But, in all
cases the burn rate would be the same and it is precisely the burn
rates mentioned in the TRA/NAR reports.   They were trying to tell
Dumbo Dave that the radial direction controls the burn time, not the
rate.  Unfortunately, it went in one ear and out the other with no
obstructions in between.

In the outside chance that one Dave's  ATFE toadies makes a copy of
this post and gives it to him, I hope he reads the next sentence
carefully.  The propellant follows the burn rate equation of burn rate
= a * Pc ^n.   So for a given pressure, the burn rate is ALWAYS a
constant value REGARDLESS of the propellant geometry.  The burn rate
is a function of pressure, not propellant geometry and is the same in
all directions.

Paragraph 13 is also a gem.  Yes, the propellant does burn on all
surfaces at the same rate if the pressure is the same.  And yes, it
does burn normal to the surface.   I think that is what we have all
been saying, but apparently it doesn't sink.   Here is a link to the
Army's Explosives Manual

http://www.quake-art.com/docs/MILITARY%20EXPLOSIVES(chemistry).pdf

Go to page 228 on your adobe reader.  The section on Piobert's law
should sound familiar and to amateurs the following paragraphs talking
about strand burners should also sound familiar.  They are talking
about determining the burn rate of explosives using a strand burner.
And guess what, the linear burn rate referenced in the Army Manual is
the same burn rate TRA/NAR have been talking about.  It is not talking
Shatzers burn rate.  Why the Army Manual even references St. Robert's
burn rate equation: burn rate = a * Pc ^n.   The Army methods used to
obtained burn rates are the methods used by Aerotech and other
companies to get propellant burn rate data.  These are the exact
methods outlined by TRA/NAR and NOT the methods used by the ATFE.  In
fact, based on the Army manual, it is clear that the AFRL people were
technically incompetent and incorrect in making their "Linear" burn
rate measurements.  They did not follow the techniques used by the
Army and everyone else to determine the burn rate.

Where Shatzer really runs amok is the paragraph 13 statement that if
the Piobert relationship applies, the propellant is automatically an
explosive since it only applies to materials that deflagrate or are
explosives.   Wrong!!!   It also applies to the gas generator grains
used on the MX missile, which used AN composite propellant.  DOT
classified them as flammable solids 27 years ago.  Of course, Shatzer
would say the ATFE doesn't care about DOT classifications except he
kind of wrecks that defense in paragraph 14 citing DOT classifications
for justification of ATFE classifications.  You can also apply
Piobert's Law to droplets of gasoline in car engines as the droplet
burns normal to the surface and at a constant rate.   Last I looked,
gasoline was classified as a fuel and didn't have any oxidizer
premixed with it.   No offense to Piobert, but the law is really kind
of basic.  Combustion takes place normal to the surface and in
layers.   The layer is set to dr or delta r as used in a differential
equation.

If anyone doubts that Shatzer wasn't dumb enough to set his van on
fire in Utah with this rocketry tests, they need to read his
affidivit.  As they used to say in my high school geometry class: QED

John Wickman

  Judges and lawyers usually only speak legal goobledygook.  I don't
mean to be an armchair quarterback here.  But, am I the only one that
thinks our legal team is dancing around some of these basic facts?  They
seem to be falling into the BATFE trap.  Things like radial burn rate
vs. linear burn rate, make it sound like a simple difference of
scientific opinion.  Or claiming that safety fuse functions as a "slow"
contained explosion, I've always called that burning.  Then they argue
that they are allowed deference to decide which scientific opinion to
choose.
  But measuring the burn rate of a core burner by dividing length by
time, is just incompetent.  Then arguing that it is correct because
other things, (not the thing they were testing) burn that way?  This
must be challenged early and often.  Because, if I didn't know the
difference between a core burner and an end burner, this point might not
stand out at all.

Not to be condescending to the judge, but how about a simple example:
  1) Take a piece of paper 1"x10".  Hold it vertically and light the
bottom short edge.  If it takes 10 seconds to burn from bottom to top,
then we divide 10 by 10 and say it burned at 1" per second.
  2) Now take the same piece of paper.  Hold it horizontally and light
the bottom long edge.  If it now takes 1 second to burn from bottom to
top, we would divide 1" high by 1 second for the same 1" per second.
But, the BATFE, because their expert doesn't understand how things burn,
would divide 10" wide by 1 second, for 10" per second.

  If they can't correctly deal with this simple math and science, how
can we trust anything they say?

Sorry for the long vent.  I just couldn't stand it any longer.  You all
know this is obvious.  But to anyone not familiar with any of this, it
may not be.  Let's make it so.

Curtis

I wouldn't hope too hard... Walton is an obvious joke. First of all -
how long has he let this case go on? Secondly one need not look any
further than the Scooter Libby trial to know that THIS judge is not
going to let the facts speak.

Doug

Covered in the Motion for Summary Judgment previously filed as noted in
the footnote on page 6.

Perhaps you noticed the ATF's sneering response at the beginning of
their opposition. I certainly hope that our counsel will rip the ATF a
new one for lying about manufacturers data corroborating their results.