LOC Precision EZI-65 for level 1 cert motor choice

Laura,
I chose the 38 casings for my investment into HP reloadable motors. You can fly from G's (38/120) to J's (38/720 and 38/1080). The 29mm casings
don't really cover the L1 range well at the top end. The 54's are all J and up, as far as I know.
The H123W is a very nice choice for that rocket with the 38/240, though not on the recommended motor list.
The post by Larry described the four different loads each one will take nicely. I like the Redlines and the BlackJacks myself. In general, the BlackJack will have the lowest thrust (slowest burn) and impulse for a given casing. The Redline and White Lightning are moderate thrust and impulse, and the Blue Thunder is a very fast burn with high thrust and total impulse.
If you multiply the weight of the rocket in ounces (loaded, ready to launch) by 1.4, you get the minimum average thrust in Newtons recommended for the rocket to maintain the 5:1 thrust to weight ratio for safe liftoff.
Rocket Weight (in ounces) x 1.4 = Minimum average thrust (in Newtons)
My Tomahawk was about 100 ounces (with the motor - you have to estimate first then confirm when you choose a motor) so I would pick a motor with at least 140 N of average thrust to launch it. An H148R would be rock bottom minimum thrust for 5:1. A J90 would not be enough thrust to safely launch it.
The ezi-65 has a published weight of 35 ounces. Using 42 ounces as a reference with a motor (G61W is about 7 ounces), the minimum recommended average thrust for the motor would be 42*1.4YN. Any 38mm motor will launch it with enough authority for stable flight, even the G61W (check the weight) or G67R. Some of the big Blue Thunders will have it close to Mach 1. The I435T will launch it at 54 g's in the simulation. The EZI-65 is a light HP Rocket. Look for the lower thrust motors (my opinion).
The number after the slash is the approximate maximum impulse that the particular case will accomodate. Each increase in impulse of 120 Ns is another grain. 38/120 = 1 grain (G motor) 38/240 = 2 grain 38/360 = 3 grain 38/480 = 4 grain 38/600 = 5 grain 38/720 = 6 grain (full I and low J) 38/1080 = 9 grain (upper J)
All of the enclosures for a particular size have the same fore and aft fittings, even between AeroTech and Dr. Rocket. You only have to by one full motor (tube and closures) and then just the case (tube) for every other motor you would like.
I launched a 3" PML AMRAAM on an H148R for my L1 with a borrowed 38/240. An I161W in my 38/480 case was also a nice AMRAAM launch. My first dual deployment a couple flights later with the PML Tomahawk on an I195J, also in my own case - 38/600.
Al's Hobby http://www.alshobbyshop.com/store/index.asp had a 25% off thing going on this summer, maybe until September. I picked up the 240, 360, 480, 600, and 720 casings for about $200. All except the 600 - which is a Dr.Rocket - are Aerotech. The special is not listed on their website now, but you may want to give a call.

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Thanks Larry and Thomas, I missed your posts before my last reply.
Thomas Koszuta wrote:

Thomas, when you say it's not on the recommended list, whose list do you mean? Loc Precision's List? NAR's list? Please explain. I want to make sure that I can recover the rocket and I don't have any decent electronics for locating other than a transolve beeper. So I would rather fly the rocket at a lower altitude to increase my chances, but I still need to meet the certification requirements.
Thomas you are describing exactly what I needed to know before launching my 4-29ss on two F20s. I did not weigh the rocket before flight, but it had a transolve beeper, a nomax heat pad and some overly thick fillets. I'm sure it was too heavy.
Larry wrote:

I saw that some other people qualified on the H-123W so it wasn't my idea, but why reinvent the wheel. If anyone has a better suggestion to keep the rocket lower in altitude, but meeting the requirements please let me know. Thanks again-Laura
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Hell, I even launched the EZI on a G80 as a test flight (to make sure the thing works) and it lands only a few hundred feet away. If you are trying for a cert, do it as low as possible to avoid complications.
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Tai fu, I agree. After I certify I can play with altitude, but I think keeping it low is a good strategy. tai fu wrote:

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lizardqueen wrote:

I certified Level 1 on an EZI. I used an AeroTech I-161. Flew it again on an I-211. I-161 with medium delay worked perfect. Flew it, certified, rocket fell in road way, truck driver flattened nosecone with front tire. Seasoned!
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lizardqueen wrote:

Hi Laura, Welcome to the world of HPR - it's a great world in which to live.
I certified L1 using an EZI-65 and an H123W. It's plenty of motor for a cert flight and it won't go high enough to need any electronic gizmos for recovery or location. I've also flown it on H242T, H112J, I161W, and I211W. The I211W makes for a fantastic flight. I can't wait to try one of the new AT I225FJ motors (38/480 motor case).
I even did my L2 cert using this rocket and a J350W! During building I reinforced it to make it stronger and heaver for high thrust motors, but I don't reccommend putting a J350 in a stock EZI-65 :(. When the LCO pushed the button the rocket virtually lept off the pad and disappeared into the sky. It was overcast - bad. I looked and searched but never saw it again until some young spectator at the launch came up carrying it. Thanks! I have no idea where he found it. But I did get my L2 :).
I remember the first time I launched the EZI. The biggest thing I had launched before that was a mid-power AT Arreaux on a G40W. Anyway, as the EZI sat on the pad I kept asking myself if I really wanted to push the button or not. I finally got the courage and so up it went with a roar and smoke. It was absolutely awesome. I'd like to think I had a feeling similar to that of NASA people when they have a successful launch. Now I launch 2-stage rockets with 3 motor cluster boosters (like 2-J350W's & J540R staged to K185W). Although they're complex and expensive with many more possible failure modes, and more "exciting," nothing will ever compare to watching that EZI go skyward the very first time.
Now male bonding at launches is OK, but if you can pass on your secret I'd sure like to get my wife involved in rocketry too!!!
Larry Lobdell Jr.
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Thanks for the input Larry, I don't have any advice on getting your wife involved. It seems you either like building and flying rockets or not. If she likes arts or crafts, maybe you could push that angle, since designing and painting is art and you can be very creative. When I was young, I lived in a neighborhood with lots of kids (late sixties) and everyone was into Estes-boys and girls alike. I forgot how much fun it was until my nephews got to be old enough that I wanted to do science oriented things with them. I got interested again on a whole new level. These are also great opportunities to teach them about electronics as well as how to create things with their hands. There dad is great and handy also, but not too much into hands-on science. My sister likes that they get exercise chasing the rockets.
Larry Lobdell Jr. wrote:

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lizardqueen wrote:

Ah, I was a teenager back in the late 60's - graduated from HS in 1967. Estes and Centuri were cool back then, but along came college, fast cars, and... In 1990 I re-discovered rockets, and the existance of H-M motors, and at last a rocket could actually be big enough to do something :) So now rockets are way cool again, but more expensive :( I guess I really blew it - none of our 3 kids ever liked chasing rockets. JOOC, how did you ever come up with lizardqueen?
Larry Lobdell Jr.
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I used H128W(If I remember correctly) on a 29mm casing to certify... It works quite nicely.
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