Mycroft's Flock o' Rockets
Level 2 - "Mega Magg"
During the late summer of 1998, I decided to go for
my level 2 high power certification. I bought a LOC Magnum kit
and started building it. I completed the payload section and
painted it along with the nosecone. However, other projects
interfered and I set the Magnum aside.
In late June 1999, I was busy planning to go to LDRS
18 in about a month. I suddenly decided that it would be nice
to have my L2 before going down to Argonia, KS. There was no
way that I could complete my Magnum in time, but I did come up with
an idea.
Here's an excerpt from my launch report as
originally posted to rmr.
Launch Report (including my successful Level 2
certification flight!)
Minnesota Tripoli
North Branch, MN
Saturday, July 10, 1999
Saturday proved to be a gorgeous Minnesota summer
day. Sunny, blue skies, occasional high clouds, with temperatures
around 80 and the wind light to nonexistent. A huge crowd of
rocketeers and spectators gathered at the sod farm to have fun and
burn a lot of money.
I have been building a LOC Magnum for some time now.
I had purchased it with the intention of flying it for my level 2
cert flight. However, I still don't have it done. I'm afraid that
I'm violating the KISS principle all over the place with this
rocket. Moreover, I had taken and passed the level 2 written test
last month, planning to launch my Magnum this month.
Faced with what would probably be my last chance to
do a cert flight before LDRS, but without a rocket ready to fly, I
sat at work on Friday, staring at my Minie Magg and contemplating
putting a J350 in it. (I keep my Minie Magg on my desk at work. It's
a good tool for starting conversations with visiting customer
representatives. Plus, it just looks cool.) A few quick simulations
showed that the Mach number and max acceleration would be a bit
much. Just then, inspiration hit me. At home, on the floor, were the
completed and painted payload section and nose cone for my Magnum! A
few rough simulations showed that, with the added weight of these
components on top of the Minie Magg, max speed and acceleration
would be held down to the levels experienced by my normal Minie Magg
during an I357 flight (which I've done, several times)
After going to the local NAR section's summer picnic
on Friday night, I went home and started assembling the beast. I
removed the normal Minie Magg nose cone and its normal elastic shock
cord. I then installed 20' of tubular nylon out of the box o' stuff
in my closet, a Rocketman Nomex heat shield, and a Rocketman R7
chute. The Magnum payload section and the long Magnum nose cone went
on the top. Weighing this beast, I checked the CG without an engine
installed. VCP and Rocksim told me that I would have about half a
caliber of stability margin in this configuration (which is about
all my Minie Magg ever has in its normal configuration), so I added
a bunch of stick-on lead weights from my R/C airplane supplies
inside the front of the payload section, just to be paranoid. WRASP
predicted altitude was about 2100 feet for a GLOW of about 110 oz..
Saturday morning. The Launch.
 I
assembled a J350-M and installed it in the Magg. Carefully, in went
the heatshield, tubular nylon and chute. It was a tight fit.
Especially since the motor mount tube in the Magg is only 10 inches
long; the J350 stuck out the top end of it by several inches. On
went the payload section, with my Cornfield Paranoia beeper clipped
inside, nose cone, and then the 6 screws that securely lock the
nosecone to the payload section.
Filled out my flight card. Checked the CG versus the calculated CP.
Looks OK. Tried to drown the butterflies in my stomach with
lemonade. Unsuccessful.
Showed the rocket to the prefect and talked it over with him. He
said "Good luck". Checked my flight card with the RSO, and
the LCO assigned me an away pad. I installed a Firestar and set the
rocket on the pad. Dubbing the rocket "Mega Magg", I
decided that it was as ready as it was going to get, took a photo,
and walked back to the flight line.
Pretty soon, it was my turn - WHOOSH! It was a nice, straight boost
with no spin or funny behaviour. Ejection appeared to be almost
perfectly at apogee. The chute deployed, and the rocket drifted
downrange to a good landing on the sod.
YAHOO!
Retrieval and subsequent examination of the rocket
showed nothing more serious than a couple scratches in the paint at
the tip of the nosecone. Soon after, the papers were all signed, and
now all I have to do is mail it in tomorrow.
For a second flight of the day, I loaded an H238-M
in my stretched, zipperless-converted, highly reinforced Graduator
(the poor thing...) Another perfect flight and good landing.
Having stayed out of the cornfields, achieved a
level 2 cert flight, and suffered no damage, I decided not to press
my luck and spent the next hour and a half working the RSO table.
After that day, I derated the Mega Magg back to just
the Minie Magg. I don't plan on ever flying the Mega Magg
configuration again. I still haven't finished that
Magnum. And after all that work & hurrying, I didn't fly
anything bigger than an I motor at LDRS 18!
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