[music playing]
- So welcome to the
2015 NASA Ames Summer Series.
When we think
of Saturn, Apollo,
when we think of those missions
and that time,
we think
of a great time
for rocketry
and space exploration.
We also look at it as an era
where we could do--
and we do in this point--
have a lot of lessons
learned from.
Complex machines were built
to get us into space
and have humans go to places
as far as the moon.
Today's talk,
entitled
"Destroy Saturn V!
and other Apollo Topics,"
will be given
by Bill Colburn.
It is actually
quite interesting,
the career of Bill,
Bill's career.
He thought of and looked at
science fiction
at the age of 11
and said,
"Wow, I want to go
into that area,
drive science fiction to
reality, make it real."
He enlisted in
the US Air Force in 1954,
still with the interest
of following that dream.
He worked for
three and a half years in NSA,
serving the USSR development
in rocketry,
then after that went
to Livermore,
and then Ted Parker
brought him over
to the test range
in China Lake.
He was a staff engineer
for Space Ordnance Systems.
He has worked and designed
and developed,
as part of the Saturn V,
the propellant dispersion sys--
uh, system
and the--
an air abort launch.
What is really interesting is,
he has made major contributions
to complex systems,
started as a kid,
thinking about the approach,
and went through there,
going to a mission
without the formal education
that you would think
somebody like that will have
in a normal system.
So following the dream
is really important,
and you could contribute
to the complexity
of missions like Saturn
and Apollo and make history.
So please join me
in welcoming Bill Colburn.
[applause]
- Thank you,
Dr. Cohen.
Uh, before any talk
on Apollo,
we really have to honor
the--the, uh, five men
who gave their life--
three of which actually,
gave their life
on a mission-related task,
and that's
Grissom, Chaffee, and White.
So my heart to them
and their heroic wives.
Well, "Destroy Saturn V!"
Well, if Saturn V
were this size,
you'd use
a Black Cat firecracker.
You could blow that up easily.
How about one this size?
You could use two cherry bombs,
but Dave would not like
me to do that.
So how about the huge thing?
Look at this.
Uh, but--
but let me give you a--
here I am.
Dr. Cohen intro--he made
a very nice introduction,
but here I am on
the Apollo Walk of Fame
at Titusville, Florida.
I'm the third name
on the first--
uh, on the
first trident there,
and looking at that,
I thought, "Boy,
that's really a great honor."
Until I realized,
"Oh, it's
in alphabetical order."
[laughter]
Well, here it is,
Saturn IC.
So Boeing comes to us
when we were General Precision.
We started
as Precision Technology
in Livermore
with some very heavies
from Lawrence Lab
who started the company.
Well, Boeing comes to us
and said,
"We want to destroy
this thing,"
which is 33 feet
in diameter,
the entire vehicle,
of course,
360 feet long,
4,880,000 pounds of propellant
in the complete vehicle.
How do you do that without,
say, taking out the entire cape,
uh, taking out Cuba,
which happens to be
in the launch area,
44 degrees to 110 degrees.
Cuba's right in there
and so are the Bahamas.
Well, you don't want
to do that.
Even though JFK
might've thought,
"Eh, it's all right
to take out Cuba."
But, uh, so
what do you do with--with that?
488,000 pounds--
4,880,000 pounds,
that's the equivalent
of 1 inch of propellant
across 36 football fields.
That's a lot of propellant.
Okay.
Now, what happens if, um--
if that ignites in the air?
Four and a half million pounds,
what happens?
32 football fields, equivalent
of 400,000 pounds of TNT.
What is that like?
There we are.
Really not quite.
More like this one.
So outside of protecting the,
um--any cities
that you might be in--
in the range,
you want to get rid
of everything
before it has the possibility
of going 350 miles to Cuba,
928 miles to the Bahamas,
960 miles to New York City,
so let's get rid of it
before it even
has an opportunity to do that.
Well, of course
they have the radar,
and if radar detects any
abnormality in the flight path,
they can start
a flight abort sequence.
Uh, they also
use a very interesting technique
which had been used for tracking
V-2s at White Sands,
and that was a wire frame.
And the wire frame
had two wires at an angle
and then the optimum
trajectory wire down the center.
So the guy
optically watched the vehicle.
If it went outside
of those wire-defined areas,
then that would initiate
an abort sequence.
Well, who was in charge
of the abort sequence?
I've read in some places
that it was totally automatic.
No, it was not automatic
in all cases.
It would be automatic
if the wire--
wire running down the length
of the Saturn V here and here,
if those wires
ever lost continuity,
abort sequence
would be automatic
because that indicates
a major rupture in a tank.
Otherwise, the abort sequence
was partially manual,
and it was manual
on the part of the--
of the range safety officer
and on
the command module commander.
So what happens,
and how do you do this?
Well, this is what we came up
with, with Boeing.
It took 5 pounds
of high explosive
to destroy the V-2.
In the Saturn V,
we used 9 pounds of explosive
to destroy
the entire S-IC stage.
And how is that done?
Two runs of 175 grains per foot
flexible linear shaped charge,
which I'll show you
how that works in a moment.
And there were 40-foot--
40-foot lengths
on each side
of the Saturn V.
On this model, they would be
about half the size
of a paper clip
in a cross section,
running 40 feet here
and 40 feet here.
The reason
they were on opposite sides is,
when they--when they did
the ballistic calculations,
it, um--
if the propellants had mixed,
then you would've
had that sub-nuclear explosion.
By ejecting the LOX out one side
and the RP-1 out the other side,
you would have less mixing
and a much lesser explosion.
Well, and that--
those two FLSC lines,
shown here
on their aluminum carrier--
the rectangle
on the outside,
that's the channel
that ran up.
Again, as I said, that's the--
about the size of--
of a half of a paper clip
that would run up the side here.
That was 2 inches by 1 inch,
just to give you an idea
of the scale,
and inside of that was
an aluminum carrier
that had that shape,
and the red parts are the FLSC
that were bonded in place there.
Now, this is an interesting
assembly because everything
was done with adhesives.
There's not a single
mechanical joint
in that
propellant dispersion system,
which is extremely interesting.
Even the Skunk Works,
I understand
when they used adhesive,
they always put in
what they call chicken rivets,
just to make sure that
their adhesive doesn't fail.
This entire thing
was held together with adhesive.
It was a urethane that was
qualified to -280 degrees
for the LOX tank.
So what happens?
Well, when we initiate that,
this is what happens.
It cuts a 1-inch wide gap
in the
2019 aluminum tank structure.
And do you see the little ribs
in that tank?
That's an amazing thing.
We may not be able to make
a tank like that right now.
That was made by taking
enormous sheets of 2019 aluminum
and then milling a pattern
to reduce the wall thickness
but retain the ribs
for stiffening.
That was about roughly 1/4 inch
in the thin section
and 1/2 inch on the ribs,
and then they would roll
that and weld
that into these enormous tanks
that were 33 feet in diameter.
Incredible technology.
Now--so now we have--
we have that happening.
We have the propellant squirting
out each side of the vehicle.
But wait a minute,
we forgot the astronauts
in the command module.
We can blow up--
we can blow up the S-IC
and the upper stages.
That's fine.
But how about these guys
up here?
We got to get them
out of the way.
Well, already,
they had the escape tower
and the escape rocket
designed and built for
emergency abort from the pad.
Now, they wanted to determine
if we could--
if they
could also use that
in various stages
of altitude and velocity.
Um--incidentally,
the Saturn manual calls--
the Saturn V manual
calls this a small rocket.
This rocket had 147,000 pounds
of thrust for four seconds.
I don't call
that a small rocket.
That's three times the thrust
of the V-2,
and that burned for,
as I said, for four seconds,
and that would, uh, from a--
from a standing start,
that would take
the command module to 4,100 feet
in 11 seconds.
So they determined
that with a manual--
even with a manual abort,
they could get the command
module far enough away
that the ignition
of the RP-1 and LOX
would not affect
it detrimentally.
So then what happens?
Well, canards pop out.
If it's a low-altitude abort,
canards pop out,
and the canards
veer the command module
away from the direct trajectory
of the--of the vehicle.
If it's at high altitude,
there's a pitch motor, a small,
solid-propellant pitch motor.
So if it's at 280,000 feet,
which is the maximum feet
for an abort,
the pitch motor--
the pitch motor would tilt
the command module
and get it out of the way.
Then they would fire the bolts
that held the, um--
the, uh, rocket tower
to the command module,
and that would pull off
the ablative heat shield.
There was
an ablative heat shield
over the forward heat shield,
pull that off.
[coughs]
Then they had to get rid
of the forward heat shield
because that was covering up
the parachutes.
So let's use
the parachutes next, all right.
That's a very good idea.
Then the drogue mortars
would fire.
The drogues would go out.
Reefing line cutters would open
the drogues,
and then the drogues
would pull out the mains,
and you would have
a recovery.
Now, boy, how did they know
that was going to happen?
Oh, this is the CDF carrier,
incidentally.
This is, um, CDF,
a confined detonating fuse.
It's two grains per foot.
It looks like solder.
It looks just like
a little lead solder
and, uh [coughs]--
two grains per foot.
That was inside of a--
of a polymer coating,
and then the polymer
had fiberglass tubing over that
and then another polymer
coating and then another layer
of fiberglass.
So when the confined
detonating fuse detonated,
and that's detonation
that's extremely rapid process,
the detonation
would be completely confined
and wouldn't--wouldn't disrupt
any of the mechanical
or electronic components nearby.
The CDF is what started
most of the processes
onboard the Saturn V
and onboard Apollo
because it
was virtually instantaneous.
At 8,000 meters per second,
that--that's pretty fast.
So the, uh--
and the CDF in all cases
was initiated by what's called
an EBW detonator.
That's exploding bridge
wire detonator,
and the reason they use
exploding bridge wire detonator,
it is completely insensitive
to electrostatic discharge,
completely insensitive
to low current.
In fact, you could take
an EBW detonator
and plug it in the wall,
and it would not initiate.
It would fizzle and burn,
but it would not detonate.
So they used EBW detonators,
the safest possible way
to initiate the CDF
and initiate
all of the various functions
that had to happen in the Sat--
the stage separation,
the command module separation.
The docking ring separation was
also done with--
with detonating cord.
[clears throat]
So--so here we are.
We've protected
the astronauts.
We've dumped the propellant.
We're pretty safe.
This is the crossover
we're talking about, the CDF,
and you notice
the manifold paths.
We have two CDF lines
coming in, simple redundancy,
but each line has
a crossover,
so we have double redundancy
in this connector.
We have two FLSC runs.
Pretty much
a very high-reliable system
because if any one
of these, uh, paths failed,
you'd still initiate
both of the FLSC lines,
and you'd still
cut the tank,
uh, and that's
extremely important
because one FLSC line
would not open the tank.
It would just make a slit,
and it would dribble out
over time,
but it would not--
not be a true abort.
That's a CDF connector.
That has a curious thing.
It's a--
it's a spring-loaded lock.
You can see the grooves
on there,
and that was--
as far as I know,
that's peculiar
only to CDF connectors.
I haven't seen it on
a hydraulic system,
for instance.
Now this is getting--
moving over to the rest of
the Apollo pyrotechnic systems.
This is the basic standard
for initiating
nearly all of the pyrotechnic
systems outside of the EBW,
and that's called
the NASA Standard Initiator.
Um, the last I checked,
this has
a reliability of 99.9995
at a 95% confidence level,
which is astounding,
astounding.
And so that--that may be
the most reliable component
in the entire--oh, except
maybe a few resistors, yes.
So--
So here's how we determined
if that escape system
is going to work at altitude
and at velocity, the Little Joe.
There's the Little Joe.
You can't quite see it,
but in this, um, mockup
in a, um--
in a rocket graveyard,
the nozzles
are put in upside-down,
but there we are.
So that's the Little Joe.
That was 86 feet tall,
8 1/2 feet in diameter,
and look,
176,000 pounds.
Pretty big rocket.
It had a couple
of Algol motors,
and then I believe it--
it had different combinations,
depending upon
what the mission called for.
That was, for all
of you model rocketry people,
this is the world's largest
clustered high-powered rocket,
and there it goes.
Now, at altitude,
what would happen is, um,
they would go through
all of the abort functions
at a different altitude
and different velocity.
In every case, the command
module was recovered safely.
In fact, in one case,
the Little Joe--
due to a--a problem
in the flight computer,
the Little Joe exploded,
and so they had
a real emergency
and the command module
safely recovered,
even in a real emergency,
so they counted that as sort
of a--an unexpected--
unexpected win.
Now, the Little Joe--
we mentioned
the drogue mortars
The drogue mortars--
what I'm going through
is in my personal history,
so it might be a little
disconnected to you.
But the drogue mortars
had reefing line cutters.
The reefing line--
what the reefing line would do,
it would hold the--the drogue
closed for eight seconds,
until, uh--
until everything became stable.
Then the reefing line would cut
the, um, the reefing line.
The reefing line cutter
would cut the line,
and the drogue
could open fully.
And then after that point,
at the proper altitude,
the drogues would pull
the mains out,
the three main chutes.
Now, to remove
that forward heat shield,
we designed this:
the type VI pressure cartridge.
Now Hi-Shear had tried--
this is an amazing cartridge
because it produces
up to 20,000 PSI in a plenum.
There are two 1/2
inch stainless steel tubes
that run off to, um,
essentially, pyro pistons,
and those pistons
force the heat shield off
at 80 feet per second.
That's a 280-pound heat shield,
so that's a lot of force.
If any--if any
two of these cartridges fired,
the heat shield would be
ejected safely.
And the reason you wanted
to get that velocity is,
you didn't want that forward
heat shield, 280 pounds,
to come back
and hit the command module
and perhaps, um, injure it
in some way,
like the heat shield--
its own heat shield.
[coughs]
So, uh, there were
four of those.
Four of those
and four, uh, pistons
that ejected the command module
forward heat shield.
And the type VI pressure
cartridge had--it had a--
since it was so unusual,
it had to produce
that 20,000
PSI in a few milliseconds,
so it was
what we would call brisance.
It was a very
rapidly operating cartridge--
so a high burning rate.
The burning rate
of the propellant we used
at this pressure
was 1,600 inches per second.
That's unheard
of in solid propellants,
but we used permeable burning
to get that rate.
Uh, and we're talking
a 5-inch long grain.
That 5-inch long grain
would burn in
a couple of milliseconds.
Amazing.
And in order to ignite it,
since it had a very high--
it's called burning rate coef--
the burning rate exponent.
The burning rate exponent
of a good propellant
would be around
0.25, 0.3, 0.4.
It means that's its sensitivity
to pressure.
This propellant had a burning
rate exponent of 0.83.
It means that it's
highly sensitive to pressure.
So because of that,
uh, it was prone
to what we call a DPDT failure.
That's the rate
of pressure drop.
If you had a high rate
of pressure drop.
This propellant could quench
because of its high--
high burning rate exponent.
So what we did to ignite
it satisfactorily is,
we had a two-phase opening
of the closure,
and that's
a chemically-milled closure,
which was a first
at that time.
So the, um, the light gray area
would open first.
We're talking milliseconds
now too.
The light gray area
would open first.
Then burning
would be established
while the other petals
were still there,
and then they would open,
and you'd have the continued
burning of that grain.
Type VI pressure cartridge.
So the docking ring
had to be beefed up for the--
the docking ring
had to be beefed up for the--
to separate the LEM.
Originally,
it wasn't strong enough,
so just before the, um,
the first--
before Apollo 8, they
had an emergency development
to develop
a long-reach detonator
to, um--to fit
in the new docking ring.
Well, we did that,
and--very simple.
We just added an extension,
but that extension couldn't
be filled with explosive
because then it
would be too much explosive,
and it would've distorted
the ring.
Not a good idea.
So that's the
long-reach detonator,
so it had essentially
what we call
a flash tube
from the NSI to the explosive.
It was just an empty tube.
And then the, um,
thru-bulkhead escape motor.
That, yes, okay.
The, um--
for maximum reliability,
we decided not to use
a glass seal or a ceramic seal,
although they work perfectly
well in most rocket motors.
This was a metal-to-metal seal,
so there were no--
[clears throat]
there were no, um--
everything in that rocket motor
was metal-to-metal sealed,
and this is how that works.
If you see,
the upper part of this drawing
is where the
CDF connector attached,
and that CDF initiated
the first little red zone.
That's a--
that's a PETN explosive.
The shockwave would go
across the little bulkhead,
and that shockwave would
initiate the second PETN charge,
and then that would initiate
the output charge,
which is--would start
the rocket motor,
and that's
a thru-bulkhead igniter,
And I think we're gonna have a
lot of time for questions here.
Dr. Cohen?
- Thank you very much.
So we have time
for questions.
If you have a question,
please raise your hand
and wait for your mic--
the microphone to get--
to get to you.
There's a--mic.
All right, go ahead.
- Um, how much of this
did you design yourself
of these devices?
- I'm sorry.
Can you--can you--
- I can repeat it if you want.
- How many of these devices
have you designed yourself?
- Oh, all of them,
excepting for the, uh, NSI.
I did not design the NSI,
but everything you saw here,
I designed, yes,
and followed
through production.
In some cases,
hand-delivered.
Hand-delivered to
White Sands
in time
for the Little Joe II tests.
Uh, we hand-delivered
the first FLSC
to the Cape--
not to the Cape.
Um, that was the F-series,
the F-500 series,
which was a fit-up.
I assume F stands for fit-up.
And we delivered the, um--
the propellant dispersion system
to them for fit-up.
Incidentally, that, um--
that 2-inch by 1-inch aluminum,
rectangular tube,
that was slotted at intervals
to take care of the contraction.
As the LOX tank was filled,
the tube, of course,
would contract
a couple of inches,
and so those slots would aid
in--in that contraction.
Well, they forgot to, um--
to, um, take the--
when they milled through,
they didn't deburr the interior
of the slots.
So when we tried to insert
the FLSC carrier in,
it got halfway in and stuck.
Well, good thing
they did the fit-up test first.
So after they cleaned
those all out, we were fine.
But we also had--
the specification
was for 220-pound pull.
We had to make connectors like
this that would take 220 pounds
to connect each 4-foot length,
so we'd have ten 4-foot lengths
connected like this.
220 pounds was not enough,
even though
that was the specification,
so we changed that.
We put a single bar
of A286 steel
with a eye at one end
and a hook at the other end,
and that had a--probably
a breaking strength
of maybe 2,000, 3,000 pounds
of force.
I hope
that answers your question.
- Um, I understand that
before the shuttle project
was started,
the goal was to have no
pyrotechnic devices
on the shuttle,
and it ended up having over 300.
I was wondering,
it seems to me
that pyrotechnic devices
are the--
have the highest specific power
out of any way
you can actuate or ignite,
and--and also, the reliability
is extremely high.
Why would one not use
pyrotechnics?
It seems like a good approach
to me.
- Probably because of the--
of the regulatory--
the regulatory problems
and the fact that when you arm
pyrotechnics on a launch site,
then everybody else
has to clear away.
And so when the pyrotechnic
is armed,
that's a--that's a specific
safety condition,
and you have to observe
that condition.
So if you don't have them,
maybe it's a little better.
Maybe.
But you're right.
Reliability is incredible.
- Thank you.
Very interesting talk.
Did North American design
the first stage,
and how many detonation tests
were run,
and was any type
of stress analysis
done during the development,
or was it more
of a trial-and-error process?
- Could you repeat that?
- Did North American
build the first stage?
How many detonation tests
were done,
and was any stress analysis
done in the development,
or was it more
of a trial-and-error process?
- So did North American
build the first stage,
how many detonation tests
were used,
and was any stress analysis
done?
- Oh.
Well, if you look the SW--
the NASA SPs of that era, oh,
my heavens, yes,
stress analyses were done.
There--there's an SP
for almost every type
of structure, you know,
conical, cylindrical, whatever.
So yes, I'm sure
stress analyses were done.
There's also pyro shock,
and pyro shock
was a major problem.
In fact,
it's been a problem in
some of the--
I believe on maybe
on the Mars Observer,
possibly.
And so a lot of studies
were done on pyro shock,
and Larry Beament
was at Langley.
And Larry Beament was
responsible for--
for really bringing pyro--
the pyro black art
down to a science,
and if you look up some
of Larry Beament's publications,
you'll see that he did
an excellent job in that arena.
- Hi, Bill.
Um, I know Bill.
He's a great guy,
and I've been down to his shop
in Hollister,
and my question is,
you've worked on a lot
of these projects
for this program,
but currently,
you're still designing
various rocketry programs
at your offices in Hollister.
Can you just give us
a real quick, brief description
of what you're doing
down there now?
- Okay, do you want a check
or a money order?
[laughter]
Well, thank you, Charlie.
Yeah, Charlie
has been to our--
yeah, what we're doing
in Hollister,
we're working
on hybrid propulsion systems.
And, uh, in 1951,
this little rocketry group we
had in Watsonville, California,
fired a hypergolic hybrid,
probably the first one ever,
and we used, um--used a--
a German oxidizer
which is 90% nitric acid,
10% sulfuric acid.
Since it has sulfuric acid,
we knew that it would react
with potassium chlorate,
so we put a little potassium
chlorate in the asphalt,
and we had a hypergolic hybrid.
So what we're doing is,
we want,
since hybrids are
incredibly safe
until they're loaded,
as are bi-liquids, too,
they, um...
they represent a, uh--
an arena between
an area between
solids and--and liquids,
and they have about
half the complexity of a liquid,
so they're kind of attractive
from that viewpoint.
ISPs--
My partner is a Harvard chemist,
um, Ron Winston,
and he has developed
several propellant additives
which boost it right over 300
seconds ISP at sea level,
so that's pretty incredible,
and that's what we're working--
that's what we're working
towards is very high
ISP hybrids.
That's it.
- Hello, um--
how did you guys
validate the analysis
for the pyrotechnics
on the stages
for detonating the stage
on abort?
- Whoops.
I didn't hear that one.
- In terms of the analysis
of coordinating the pyrotechnics
of successive stages,
how did you verify them?
- Ah.
Well, that's Larry Beament's
favorite subject
because Larry--Larry called
what we did black art,
as I mentioned before.
And we did--
what we would do,
instead of approaching
it analytically,
we would do off-limits testing,
uh, qualification testing.
Uh, so that's
primarily how--
how the pyro systems developed.
So off-limits testing would be--
we'd change the loading
until it didn't work on one end,
and it worked too well
on the other end,
and that's the extent of it.
Very--very little analysis.
Now it's quite different
since Larry attacked the problem
some 25 years ago.
- Appreciate the discussions.
Your comments on
Little Joe kind of reminded me
of a long time ago
where Little Joe
and an associated program
called Little John
uh, was gonna be used, uh,
not for space,
but actually do a very--
a multiple numbers
of Little Joes
and Little Johns
to actually thrust
and change the, um,
rotation of the earth
in the event
of a nuclear exchange.
Do you have any comments
on that or remember that at all?
- Oh, hmm.
In the realm of my interest
but way outside of my expertise,
sorry.
- I have a question.
I don't know
if my mic is up now,
so the question
is in terms of risk culture.
So, you know, when you look
at the era of Saturn and Apollo,
you see that there were
accidents that occurred,
both with humans
and without humans,
but you saw a progression
of the rocket's design,
the systems, or the--
and so on your stage
of engineering,
how had the culture of risk then
in terms of the ability
of taking risks
to develop new technologies
to move forward,
versus now
as a culture that is,
whether it's within NASA
or the industry
that you're working on,
in terms of that?
Are they the same
or different between those two?
- Quite different, Doctor.
The, um--
we had--
we had a whole section
of designers,
and the designers were familiar
with MIL-SPECS, for instance,
that we didn't have
to bother with.
So if we wanted to use a certain
bolt, they'd go,
"No, no, no,
you can't use that bolt.
You got to use this bolt."
And so we were--
had that kind of support.
Uh, we had
a secretarial pool,
and so that
took another load off of us,
so we were free
pretty much to--
to imagineer
our projects.
The advent of the computer
changed all of that,
and now each engineer
is his own draftsman,
drawing guy,
secretary, you know, so yeah,
it's considerably different.
I think that an engineer now
needs to have more skills
than we had.
We were a lot
more focused though.
We were, I think,
far more focused on the job
than you can be now
because you have to have
this wide panorama of skills,
so that would be my answer.
- Okay, so please join me
in thanking Will Colburn
for an excellent seminar.
Thank you.
[applause]
- Thank you very much.
- Thank you.
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