I'm inclined to agree with Hyam. I used the EZI to do my Level cert on
a J90 and it was a real pleasure to watch, a crowd pleaser too. I did
most of what you described except the fins were left stock. There are
some pictures on the Website along with the following description:
"In this series, we have a modified EZI on an Aerotech J90. It carries
an 18" PML drogue and a 36" LOC main chute all protected by Nomex. The
chute's are deployed by a Transolve P2 Altimeter fireing Robbie's LES
units top and bottom. There is also an ALTS2 to perform backup altitude
measurments. The payload modifications add a total of 6" to the overal
length. There are four centering rings in the bottom end to stiffen the
fin section. With the J90 loaded, the weight is up to 6 lb 11 oz. This
flight went to a peak altitude of 3763 ft. and landed about 100 yds from
That's a "little" <g> on the heavy side, hence the 3763 ft altidude.
I've been thinking about glassing the fins and giving it a try on a
K-185. That will burn forever and not rip the paint off the tube as it
lifts off the pad.
Good luck with your Cert!
TRA# 4895 L2, NAR 69114 SR
Tripoli Michigan Team-1
> To me, it doesn't make a whole lot of sense to go for Level 2 if all you
> have is the 38/720 hardware, so the only Level 2 reload you'll be able
> to fly is the J350.
> If you get the RMS 54/852 hardware set you have many more options- J460,
> J275, J90 and my personal favorite, the J180. Achieving Level 2
> certification in the EZI-65 with a J90 is a much surer bet- that rocket
> was designed expressly for long-burn low-thrusting motors (hence the
> name "I-65"). It won't require modifications to the rocket and entails
> the fewest risks. The J180 should be likewise.
> Then once you do certify, having the 54/852 motor gives you way more
> leeway in motor selection so you can tailor the flight profile to the
> rocket and the flying field. With the 38/720 casing you have only one
> reload to fly, which means that every rocket you build must be able to
> take that kind of high impulse. (I know that Aerotech is rumored to be
> developing other reloads for that casing, but right now, it's a
> one-trick-pony). It just doesn't seem to me to be as much fun as the
> ability to use all sorts of different motors.
> And the "Restricted Access" reloads don't entail any extra legal hassles
> over the J350 (at least here in the US) as long as you purchase them at
> the launch and then use them at the launch.
> -Hyam R. Sosnow, TRA #1526 L2 (on a stock LOC Magnum with a K185)
> > Hi There.
> > Well ... the time has come, this year I'm planning on certifying level
> > 2 (actually, it's level 3 under the CAR rules, level 2 being "I"
> > motors here). Anyhow ... I'm planning on seriously beefing up an
> > EZI-65 so it can take the pounding of a J350 reload. Any advice
> > there? I don't feel like fiberglassing but I will be replacing the
> > plywood fins with G10 fins, and will add two more centering
> > rings and will assemble the "fin canister" seperately to make sure
> > I apply epoxy on every ajoining surfaces. I'm also going to lengthen
> > the motor tube and the rocket itself by about 12 inches.
> > Also, I hear that the "shape" of the EZI fins is one of the reasons
> > you really can't throw high impulse motors into it, so I'm planning on
> > altering the fins to be shaped more like the ones used on a Vulcanite.
> > Finally, I'm also going to use two-stage electronic deployment with an
> > Adept ALTS25 high-low deployment system.
> > Any other advice or should this combo fly fairly well?
> > [Note: I have enough tube couplers to fill up the whole damn thing if
> > I have to as well ;-) ]
> > --
> > Yves || A3MAQ Prez || http://www.FoundCollection.com/
> > CAR#S255, L1 Certified.