This past Sunday, I made the trip from my summer house in C***te NC,
to the Orangeburg S.C. launch site. It had been over 9 months since I had
last inhaled AP, so I was in drastic need of a fix.
Although launching had not been an option for me during those 9 months,
building had. During the time, I had managed to finish two models, both
glider derivatives. The first model was my A4.b 10, a 10 cm (3.9") wide
version of the German missile of the same name. I had built a 2.6" version
previously which had worked well and glided impressively. The 3.9" version
was built tough and light, with a carbon fiber tube (graciously given by Tom
(don't know his last name) IBPYRONSKI) and LOC 29MM motor tubing, and LOC
Plywood centering rings.
The second model was my Saturn VII. This model I began at the beginning
of last summer. It is an exercise primarily in building a large model that
can be flown on relatively small motors. Essentially, I was attempting not
to overbuild in any way, but still build the model to take what I was
interested in throwing at it. The model was built ribbed style, with a 29 mm
tube running up the center in the bottom, and a 2.6" tube going the rest of
the way to the top. The model was tall, over 6' finished, and the centering
rings were made out of foamboard, with the bottom two fiberglassed for
strength. The diameter was 7.5". The outside body was created by wrapping
posterboard around the centering rings. Bottom line is the model is sturdy
only on one axis, the vertical one. The body can be pushed in in every point
where there isn't a centering ring. The advantage of this is that the model
only weighs three pounds fully loaded, which allows it, an over six foot
tall 7.5" diameter rocket, to be flown on motors as small as G's.
The other aspect of the rocket comes from it's "purpose." The model is
essentially a F/F model that is a design for a transport for Mars
colonization, with four transports located on the top, each a glider. The
four gliders are each hinged, and they fit together in a cross pattern. At
apogee, the parachute pushes them off the top, and they are free to unfold
and glide down. The model is lowered on a 5' chute to bring it down gently.
Well, now that I've gotten over the boring stuff, on to the launch
report! I arrived at the launch site, along with my mother and sister, at
around 11. I quickly unloaded the two models, and after paying the one day
launch fee, started prepping. The first model that I prepped was my A4.b. I
set up the hing system, with threads going through the motor mount tube to
hold back hinges that would active at apogee when the ejection charge burned
through them, and put in the top of the stuffer tube the weighted nose cone
that would eject out at apogee to cause a CG shift for the glide mode to be
activated. The chosen motor for the flight was a 3 year old F20-4 econojet
that I'd had in my launch box indoors for the past 2 years. I double and
triple checked everything to make sure everything was in order. If there is
going to be a problem, I thought to myself, it sure as hell isn't going to
be because I do something stupid.
Well, the ICBM SC launches are fairly laid back, without an official
RSO, so it took a minute, after I showed the model to the launch treasurer,
for RMR's own Tom Binford to be called over. It's always nice to meet some
fellow RMR people, and Tom Binford seems like a really nice guy. Anyways, he
okay'd the rocket, and I placed it on the end of the rack.
After launching everything else, the heads up was called, and the rocket
was ready to be launched. 5..4...3.....2......1............Launch! The model
exploded off the pad, those F20's seem to have a nice little kick at the
start, and started arching slightly away from the crowd. The boost was very
stable, without any significant spinning, and the model didn't appear to
weathercock significantly. The model passed apogee at what looked like
slightly over 500 feet right around the specified delay of 4 seconds. An
kept falling. And kept falling. And kept falling! "C'mon, eject!" I remember
pleading with the rocket at about 100 feet. The rocket gods have to have
there sacrifices I suppose, and destiny took hold as the rocket slammed into
the ground. I thought I could hear a puff of smoke and an ejection charge
right after impact, as the model bounced backwards slightly, but it was
fairly far away so that could have been a delusional dream.The moment of
silence could then be heard to break as a few people could be heard groaning
for the model, at least that's the closest sound I can think of to the
"ewww..." that echoed in the air.
Salvage wasn't too bad overall. I went out to the model to find that the
carbon fiber tube was completely unscathed, as were the wings which were
glued onto it, except for a small chip lost off of one of them. The rear fin
section was also in fairly good shape, none of the fins were damaged at all,
and even the hinges remained in good shape. Unfortunately, the ACE nosecone,
the most expensive part of the model, was damaged beyond any sort of repair,
and the motor tube where it connected to the body tube was damaged, leaving
the rear section kinda hinging off. What a time for the first bonus delay
I've ever had!
I was a little apprehensive about launching again. Is there a such thing
as a cursed day? If you have one failure, does that make it inherently more
likely that you will have a failure again? Is it a sign that perhaps it's
time to call it a day and cut your losses? Well, after making a quick stop
to Ken's Performance hobbies booth to pick up some G35's, a set of Launch
lugs, and some ignitors, and wandering around for another hour, I finally
decided that it would be a shame to bring my Saturn VII all that distance,
and leave it sitting on the ground. I did, however, spend some time
reinforcing and improving the way that the four gliders sat upon the model.
I was not eager to have another failure. I rolled the 5' square parachute,
packed the model with wadding, and inserted the motor, one the G35's that I
had just bought. It was the motor that I had designed the model for.
Once again Tom Binford checked the model out, and okay'd it, and I
brought it out to the pad. It took a little effort to get the model on the
launch rod, with the wind that had seemingly just picked up, right in time.
As I inserted the ignitor and connected the leads, a small fly hovered right
next to my ear. In my semi-delusional state, still shaken up by my A4.b
failure, I could have sworn the buzzing was singing (begin musical notes)
"It's gonna crash, it's gonna crash, it's gonna crash!" (end musical notes).
For a brief moment, I seriously considered removing the rocket from the pad
and backing out before it could be too late.
A few minutes later, the model was ready to launch. It looked ridiculous
out on the pad, one of the largest, if not the largest rocket, of the day,
on one of the smallest motors of the day. After the countdown, the motor
ignited, and smoke billowed out of the bottom, as the model thundered into
the air. The black smoke seemed to pour from the bottom as the rocket slowly
rose, it's ascent slower than any other model I have ever seen, including
the Saturn V models that I have seen flown on D12s. At about 100 feet the
motor ceased burning, as the model continued to coast up to about 250 feet,
where it began to turn over slowly. At probably 20 feet below apogee, the
motor ejected, and the gliders shot off the top, as the large red parachute
billowed into existence. Two of the gliders immediately began to spiral
down, while the other two remained connected for another 30 seconds or so,
before seperating from each other and beginning their glides. I had not
really taken much time to trim the gliders so the glides were decidedly
unspectacular, with the longest being perhaps 20 seconds. It didn't matter
though, becuase the effect was spectacular. The rocket itself was the last
thing to touch the ground, the large parachute gently bringing it down
directly on it's tail end. The model stood as if it was going to stay
vertical briefly before it tipped over and fell gently on its side. Instead
of "ewwws" there were "ahhhs," which is always nice.
Well that's it, that was the launch day, we had beautiful weather, and
great company, and all in all it was a good launch day.
As for the A4.b's demise, I plan on writing Aerotech to attempt to get
some sort of reimbur***t. I put a lot of time into the model, probably
over 40 hours, and probably had about 30 dollars worth of merchandise ruined
in the flight. I'm positive it wasn't human error that caused the bonus
delay, because I pushed the ignitor fully into the motor slot, and the motor
was kept in good condition. When I mentioned that I would write to Aerotech,
however, most of the people at the launch simply laughed, apparently
considering the idea of Aerotech doing anything laughable. One can always
hope I suppose.
Info on both of the models can be found on my website (see signature)