July 28 2007 launch report (7/28/2007)
On Saturday, July 28th, MASA held its seventh launch of the
year. This launch was held at the sod farm near Nowthen.
It was darn-near-perfect rocket flying weather. Sunshine,
blue skies, warm temperatures (but not too hot) with just a light
and variable breeze (mostly out of the S-SE). The 9-foot-tall
EVIL corn was in abundance around the sod farm. A few rockets
found their way into it, and only some of those found their way out
again.
The theme for the day was "clusters"! Many fliers took the
theme to heart and had some fun with it. There were a total of
24 flights that used a cluster of 2 or more engines.
This launch saw the first-ever hybrid motor flights at a MASA
launch by Glen Overby and David Whitaker.
Thanks to the LCO/RSO volunteers: Alan Estenson, Jeff
Taylor, Ken Jarosch, and Buzz McDermott.
A few of the flights:
MASA members - please send in your thoughts about the
launch!
Dwayne Shmel writes:
It was a great day for flying rockets. I arrived later
than I wanted to but stayed for the duration of the launch. I
sent up 11 rockets in 13 flights. I started the day with a Big
Daddy (with the lunar moonscape theme) on an E9-4. There was a
slight weathercock into the wind from the ESE but it was a
stable flight with nice ejection and no damage on recovery. I
then flew the "BioHazard" Baby Bertha bash on 3 C6-5's. Wierd
flight. The rocket went straight up about 300 feet then went
sideways at about a 20 degree angle from horizontal and
downrange about 600', then it went vertical again for a few
hundred feet. Landed 1300' from pad. A later flight (last of the
day for me) of the BioHazard on 3 B6-4's had similiar results
but not to same exaggerated degree. Guess this rocket will be a
surprise flight every time.
Other highlights included an Executioner on an E9-4
(second flight for this bird). The rocket went straight up (much
better than it's maiden flight on a D motor). Perfect ejection
and recovery. There was an Estes dent in the end of the body
tube. Guess I need to make the shock cord even longer.
I flew the 18mm pyramid (the color was subtle and hard
to track - NOT!) from Art Applewhite Rockets that Ken passed out
at the picnic. I had 2 very entertaining flights on C6
motors with 3 and 5 second delays. The 3 second delay was
probably best but the 5 second delay didn't turn out to be TOO
long. The motor tube and skirt had plenty of time to tumble down
and the pyramid floated gently into the grass. Now I have
another great use for my surplus of C6-5 motors.
I launched a Thunderstar cluster rocketon its maiden
flight on 2x B6-4's. The rocket went straight up with a perfect
ejection and recovery on the stock chute. I also launched a Fat
Boy (C6-3), Stormcaster (C6-5), Flash (B6-4), and wizard (A8-3).
I sent up a SkyWriter on a C6-5 and used a streamer
instead of the 12" chute. The rocket came down fast and suffered
a slight crimp in body tube above the fin can.
I also had a drag race with my Blue Ninja against
another on C11-3 motors. I lost by about 5" off the rod. Both
Ninja's reached about the same height at apogee and ejected
perfectly for 2 safe recoveries. Lotsa fun.
Alan Estenson writes:
I flew my newly-completed Semroc Aerobee Hi on an A8-5. It
was a good flight although it took a strange kick coming off the
launch rod.
The rest of my flights were all clusters. I flew my Tube-Ces
Wild (Deuce with tube fins) on two C6-5's. The "4A-56" flew on
four A3-4t's. I built this rocket two years ago for 4A
cluster altitude at NARAM 47. It was a good flight
although it landed with one fewer fin than it started with.
My new Semroc Goliath flew for the first time on three
B6-6's. I recently repaired my trusty ol' "Wanderer"
scratchbuilt rocket and flew it for the first time in a couple
years. It launched on a D12-7 and two C6-0's and wandered
straight over into the cornfield. Fortunately, we found it after
a half-hour search. My last cluster of the day was my LOC Viper
IV on four D12-7's.
Ken Jarosch writes:
Even though I put 5-/2 hours standing in the sun I only
lanuched 2 rockets for a 4 flight total. Not my best day. What
with prepping, walking and cleaning the time just disappeared.
I had 2 C5-3's to burn up so I put the first one in a "Eggstravaganza
18 with an egg. The pod sits on top of the cone so I usually put
a piece of masking tape to hold it down on the way to the pad. I
completely forgot about the safety tape. At launch the rocket
took off with the usual C5 response. At apogee the chute, pod ,
shrod lines, shock cord and kevlar came down in a tangled mess.
But the egg survived. The cone section got a 3" zipper from the
kevlar. I taped that up and reprepped it again with the last C5.
This time every flew as expected. The 22" chute just floated
over the pad. At times it seem to climb but it ended down about
3/4 of the field. Egg survived.
Still working on lofters I decided on a repeat of the
EggsCaliber using one of my last E9-4's. I had modified it down
to just the 30" shock cord and main 18" chute. I did away with
the body 12" chute and the pod 18" shock cord. Too much internal
pressure with E9 lengths. This launched in a nice straight
flight. The chute fully opened and the rocket went down range
about 1/2 - 3/4 field. The launch was gentle, the landing soft
but the egg was smashed by the view window. No rubber support
there. I changed the 18" plastic chute for a Top Flight 9" and
put a F21-6W in for a F egglofter. Needless to say the rocket
ripped of the pad. It was way up there when the 9" chute opened.
It appeared to come down slowly but steady but still landing
over 1/2 way down the field. The egg was broken in the same view
window area. Could be the lift off or the the landing. The I
examined the rocket. One fin was smashed from the top and side.
What happened with both the E9 and the F21 appears to be the egg
pod snapped back and around to hit the fin.
I still have the F Courier and the double egg Scrambler on a
F39 to try.
Caleb Boe writes:
My first flight of the day was 3 fins and a nose cone on a
G79-8. This is a modular rocket which I will be exhibiting in
the Washington County Fair. The scratch built rocket
incorporated an ejection baffle, zipperless
recovery system, and one of my mom's homemade hemispherical
parachutes. Except for a minor tangle in the shock cord,
the flight was flawless.
Second, I flew my Richter Recker on a G71-7R. In the past I
have had a lot of problems with the parachutes tangling on this
rocket, however this time, with Chute's by Boe, mushroom style
parachutes, everything worked perfectly. In the past, I
had used a hemispherical parachute, which had a very tight
fit inside the tube, which was probably responsible for the
previous entanglements.
Next, up was my Tethys on an I218-8R. Thank you to Mr.
Cochran for providing the motor and reload case for the flight.
The liftoff was beautiful, but deployment was early, I should
not have drilled a couple
seconds off of the delay. After the rocket landed, I discovered
how lucky I was, the shock from the early deployment broke the
forward centering ring (the recovery system was attached to it)
off of the motor mount. However, it was wedged inside the tube
during descent, which prevented a separation.
Finally, I flew my Red River Rocketry P-Chuter Xtreme on a
F60-10 (Roadrunner). This was a high and fast flight,
however since there was little wind it did not drift very far.
Jeff Taylor writes:
Clusters and Corn. Saturday was a perfect day for flying.
My first flight was my FlisKits Deuce’s Wild. It has NARCON
2007 decals on it and was on display at NARCON. Mr. Jim Flis
himself autographed my NARCON Deuce’s fin, so I was somewhat
concerned about launching it, but hey – that’s what we build
them for, right? The Deuce flew twice, both flights on a pair
of C6-5s, and both flights were flawless. I also flew my Big
Bertha, Guardian, Big Daddy and a first flight on my Semroc Lil’
Ivan that I bought at NARCON. All flights were perfect. Then I
brought out my FlisKits Tres and loaded it up with 3 C6-5s. The
flight was perfect, but it landed deep in the corn on the south
side of the field. It was finally recovered after what seemed
to me like over an hour of searching in the high corn. By the
time I had come out of the corn, the launch was over and most
people had left. I don’t like corn all that much.
Ron Wirth writes:
Saturday was another nice day to launch some rockets. I
arrived at the field just after 9am to find everyone setting up
at the south end. With the corn being so high, you need to drive
all the way to the north end before being able to see that
anyone is at the south end. I managed 13 flights with 9
different rockets. I also finally
bought a 12V battery to give my Pratt Hobbies GO BOX launch
system a try. I got a couple of launches from it before it
failed. I believe it is just a battery issue. I want to thank
Alan for bringing out the community pads where most of my
launches occurred.
I launched my Estes Bullpup 12D (B4-4) that had a nice
straight flight. I put up a scratch built that I call Victor
Vector (C11-3) for the first time. It is pretty much an upscale
of a Centuri Vector-V. I launched an Estes A.R.V. Condor (B6-2)
for an interesting flight. The mid section got stuck at ejection
which caused the glued on nose cone to shoot off. The streamer
did deploy and one of the gliders did separate. No real damage
to the rocket. I sent up my Thrustline Arapahoe E (D12-5) for a
very nice flight. Someday I will
be brave and move to an E9 engine. There were two launches of my
Blue Bird Zero clone (C6-5). The first got stuck on the rod
which is a perfect waste of a motor. The second was a nice
flight. I was able to launch my newly completed Qmodeling MRS
Rogue. The flight was near perfect. The only problem was that
the rocket had been sitting in the hot sun for most of the day.
When I picked up the rocket I noticed that the tip of the nose
cone and warped in the sun.
Since it was cluster day, I launched a couple of cluster
rockets to stay with the theme. I shot my Thrustline Hank (2x
C6-5) for a very high flight. It was also the maiden voyage for
my Deuce's Wild. On the first attempt (2x B6-2) only one of the
engines ignited for a very low flight. On the next flight (2x
B6-2) the chute got pinned by an engine when it landed on the
ground resulting in a fused together mess of plastic with
several hole thrown in for good measure.
My other three flights of the day were with my just completed
Rokitflite Fake-Wulf. It is a World War II German inspired
glider with a pop pod. All flights were on B6-2s with no damage
to the glider or pop pod. The first flight ended with the glider
in a tight spiral. After some trimming, the second flight had
the glider doing a tumble recovery. With more trimming and some
testing, the third flight resulted in the glider flying for
about 10 feet then rolling over and tumbling for a bit until it
would glide for another 10 feet. I will need to do some more
test flights to get it to work.
Thanks to all who volunteered for RSO/LCO duty during the
day.
Neal Higgins writes:
I had planned on all my flights for the day to be clusters
but alas I found minor damage to 2 of them that prevented me
from flying them.
I started the day with my Blobbo on 3 C6-5's. I have this
rocket set up for multiple motor mounts. It has now flown on an
3x18mm cluster, once on a 24mm motor and twice on 29mm motors.
My next flight was my Custom Landviper on 3 B6-6 motors
followed by my Wee Viper III on 3 C6-7's. This kit is a modified
and stretched Big Bertha. I followed this up with my Viper IV on
4 E9-8's. Alas only 3 lit but it was still a good flight.
My next flight was my INXS. A 3 stage cluster loaded with 2
D12-0's in the booster, 2 D12-0's in the 2nd stage and 2 D12-7's
in the sustainer. All motors lit but it weather cocked into the
wind and by the time the upper stage lit it was about 300' up
and flying horizontally. It is somewhere in the corn to the SE
of the field. Maybe I'll get lucky and I'll get a call that it
was found during this falls harvest.
I next flew my Bid Bad Voodoo Daddy on a F23FJ-7. It floated
into the corn but I had good line on where it landed and I was
able to find it without any problems.
Next up was my 2x upscale Centuri Vulcan. I flew it on an
F50-4 for a pretty good flight.
I ended the day with my Bad Daddy on 3 E9-8's A beautiful
flight but 1 fin cracked on landing.
A total of 8 flights utilizing 24 motors of which 23 lit.
David Whitaker writes:
I only launched one rocket on Saturday, but I launched it two
times.
The rocket was a LOC HiTech that had been modified for
dual-deployment. I extended the payload bay by five inches and I
scratch-built an avionics bay. The avionics bay was based on a
LOC three-inch diameter avionics bay kit that I had built
previously. I built the LOC HiTech specifically for a
hybrid rocket motor.
My interest in hybrid motors started when I attended NARCON
in 2005. The organizing committee had invited Scott Miller of
SFSM to give a talk about hybrid rocket motors (SFSM= Space
Freak Scott Miller). For whatever reason, Scott's talk was a
giant turn-on for me. Scott had also brought several different
types
of hybrid motors which I considered fascinating.
Commercially available hybrid motors all share the same
characteristic that they use liquid nitrous oxide as an oxidizer
and a solid material (generally plastic) as the fuel.
Glen Overby finally bought into the idea of doing hybrids and
offered to buy a nitrous tank and a set of solenoids from Pratt
Hobbies (I'm turned on by technology but I'm also pretty darned
cheap!). I agreed to buy the Pratt launch controller. We
both ordered Sky Ripper hybrid motors. Glen got the 38mm set and
I got the 29mm set (the cheapness factor again). After a long
struggle with Doug Pratt, we both finally got all our stuff.
Neither Glen nor I were ready until the launch in July to do
anything (i.e. NOT Doug Pratt's fault). I'd never had any
experience with dual-deploy so I decided that my first launch
would be with a solid motor
with the ejection charge still installed.
When I arrived saturday morning, I installed a G64-7 motor in
the LOC HiTech and took it to Alan Estenson's launch pad.
I was using a PerfectFlite MAWD altimeter to which I had hooked
two Oxral e-matches. Each e-match had a one gram of black-powder
to ignite. I swapped the parachutes so that the large parachute
would be ejected as the drogue and the small parachute would be
ejected as the main.
This way the motor ejection would eject the big parachute if the
electronics failed.
I hooked up the igniter and remembered to turn on the
electronics. The altimeter reported continuity on both
e-matches (very nice altimeter!). Alan was kind enough to move
me to the front of the launch-line and the HiTech was launched.
It was a good but not high flight. I couldn't tell if the
apogee deployment was due to motor ejection or the electronics.
On the way down the main charge went off and the small parachute
was deployed at 500 feet. Inspection of the rocket showed that
both charges had gone off. I was psyched since this was my first
successful dual deployment flight. The altimeter was
beeping out 725 feet.
I immediately went and started preparing the rocket for a
hybrid flight using a SkyRipper H78 29mm motor. Motor was
already assembled. All I needed to do was install it, add a vent
tube, swap the parachutes and install new ejection charges.
After the rocket was prepped for a hybrid flight, I went and
found Glen and we started setting up the ground support
equipment for hybrids. This wasn't that difficult but it did
look kind of Rube Goldberg-ish after we were done. Alan
Estenson was kind and loaned us a six-foot quarter-inch launch
rod (Thanks Alan!).
I set up my rocket and filled out a flight card. Jeff Taylor
was the LCO so he came over. We started filling the rocket
remotely with nitrous oxide. Monotube hybrid motors like Sky
Ripper vent to the atmosphere as they are filled. An acoustic
and visual change can be seen when the hybrid motor is full of
liquid nitrous oxide and starts venting liquid nitrous rather
than gas.
At this point we asked for a quick three count and I pushed
the launch button. Nothing happened. I kept pushing but still
nothing happened. I gave up and finally dumped the nitrous into
the atmosphere.
I took the rocket down and dis-assembled it. I finally got
the igniter out and took it back to the launch controller and
tried setting it off. I definitely had continuity but it would
not burn. I hooked up a test lamp and could not get that to
light. I was really confused and looked into the launch
box for loose connections. I finally noticed the Armed/Safe
toggle was set to "Safe". Boy, did I feel dumb.
I put everything back together (including the original
igniter) and tried again. This time I remembered to arm my
electronics and flip the toggle switch in the launch controller.
Loading the nitrous was uneventful. I got a quick three count
and pushed launch button. This time a spurt of flame appeared.
Almost immediately, the motor came up to pressure and took off
with the characteristic buzzing sound of a hybrid motor. I
watched the rocket climb out of sight. I heard a pop in the
distance but nothing else. Several seconds later I heard
another pop and several people pointed to the rocket. I still
couldn't spot it so I ran over by Glen and looked down his arm.
I immediately saw it. It wasn't that far away at all.
I watched it land, got a bead on that spot and started
hoofing it over there. I went the long way but finally reached
the rocket. The altimeter was beeping out 1508 feet. Nothing was
damaged. In fact, everything looked very good. Both charges had
fired and both parachutes had deployed. I was pretty shocked
that I had so much success the first time out (knock on wood).
Anyway, Glen later launched his rocket on a 38mm SkyRipper motor
but I'll let him tell that story.
Glen Overby writes:
I made four flights at this weekend's launch. All of my
flights were about trying new things.
1. Testbed 2.6 + altimeter-based non-pyro ejection on an
F52-8
This 'contraption' used an altimeter to cut a string using a
piece of nichrome wire. When cut, a stacked pair of springs was
released, to fling the nosecone off and push out a small
parachute. I ground tested this configuration many times and
eliminated several problems (and found that I needed two springs
to push the nosecone off, not one). I flew it on an F52-8, and
it _appeared_ to work, in that the parachute was deployed by the
electronics, and it seemed to happen just after apogee. However,
since I also used motor deployment there may have been other
"kinetic events" that could have aided the deployment.
I guess I need to find a way to make the non-pyro event
distinctly separate from the motor deployment event. I could
deploy at a lower altitude (low-altitude main style). I could
use a longer delay motor, so there is an obvious separation of
the two events; that probably means flying higher with a longer
motor delay, so there is more time between events. That's a bit
scary.
2. BT-60 Payload carrier on a D12-3
I flew a "G Switch" based timer to see if the timer would
trigger under "normal" circumstances. I've never had this device
work right and the latest tweeks to the software didn't improve
anything. Additional ground tests may have given me some more
ideas.
3. 5-fin BT-55 rocket I call 5-star on a D12-3
This rocket carried a payload consisting of a homebrew altimeter
and another cut-string device to push the nosecone off. I wanted
to see if the altimeter would detect apogee at apogee, or some
time later. The altimeter did detect an apogee (it reports
altitude using a buzzer), allthough I don't know if that occured
at apogee or later. It also did not cut the string. Of course,
all of this works in a "vacuum jar" on the ground. The motor
deployed the parachute so it lives to fly again.
4. No Laughing Matter, a 2.6" rocket with a Skyripper Systems
H-124
This was the first hybrid motor I've flown. This motor, a Sky
Ripper Systems 38mm "H", uses plastic and Nitrous Oxide (N2O).
The plastic can be either PVC or Polypropylene. It's called a
mono-tube hybrid, since it uses one tube (casing) for both fuel
and oxidizer. They're separated by a metal injector / bulkhead.
Filling of the nitrous is done with the rocket on the pad, and
everyone away from it. There is a tiny vent hole in the top
bulkhead, which is vented to the outside of the rocket. When the
liquid starts venting out the hole, the N2O tank is full of
liquid N2O.
I first heard of hybrids at a Tripoli MN launch. They fly
HyperTech hybrid motors, which are more complicated and more
problematic than the mono-tube hybrids. After not flying high
power motors for a year or so, I decided to investigate hybrids.
Many of you are going to ask why I don't get a LEUP. It's
fairly simple: I live in a townhouse in Apple Valley, and there
is absolutely no way I'm going to get storage here. If I wanted
to move, the housing market in the area would keep me from doing
that for some time (three of 36 units in the community are for
sale, and one has been for sale for a considerable time). I know
a lot of people are waiting for the lawsuit between TRA/NAR and
the BATFEH to clear up the high power motor situation. I've been
waiting for seven years
for that to be resolved, and I don't believe it will be resolved
any time soon. So I went looking for an alternative.
Along with an unregulated motor, I needed an unregulated
parachute deployment mechanism. Last fall I started building an
"Eject-O-Matic" (based on an article in Sport Rocketry) that
uses elastic and a wood "plunger", released by an RC servo. This
spring I built a spring-loaded plunger, also released by an RC
servo. Flights of these two contraptions in June were of limited
success, mostly (I think) due to the homebrew altimeter and
timer controlling them. In June, I successfully ground tested
using nichrome wire to cut thread and string and decided it was
a simpler method of releasing a spring mechanism. I flew a
BT-55 version of this at the picnic.
The rocket is a generic 4FNC variety; it uses all wood glue
construction with internal "glue blocks" to hold the fins to the
motor tube.
It took a minute to fill, then a quick countdown and the
rocket screamed off the pad! Wow!
Parachute deployment was to be done by the spring mechanism I
had tested in the morning. However, something didn't work right
and the parachute never deployed. The rocket came down at an
angle and was moving pretty fast by the time it hit. I didn't
get to look at it with binoculars to see if the nosecone was
still attached. Dave Whitaker got a good line on where it
disappeared behind the trees, and helped me walk to it using
radios (we need more hams in the club so we can use more than a
300mw FRS radio!). With a lot of
zig-zaging around ditches, I finally found it.
The motor is undamaged and the altimeter only had two
connectors and a switch ripped off. I found the string that held
the springs, and it was broken about right where I would expect
it to be. Half of the nichrome wire was missing. Nichrome wire
discolors a bit the first time it is heated, and this was
discolored. Many things point to the cutting mechanism having
worked.
The Details:
Full launch tally (in Adobe Acrobat PDF form, requires version
6
or newer of the Acrobat reader)
The totals were: 126 flights, 173 motors.
The cumulative total impulse was 4257 Ns with an average total impulse of 24.6 Ns.
The motor breakdown follows:
|
Type |
# Burned |
| MicroMaxx |
0 |
|
1/4A |
0 |
|
1/2A |
0 |
|
A |
15 |
|
B |
37 |
|
C |
56 |
|
D |
18 |
|
E |
22 |
|
F |
14 |
|
G |
8 |
|
H |
2 |
|
I |
1 |
|
J |
0 |
(Alan Estenson)
|
