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L1 Certification Help

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10 months 2 weeks ago #11780 by Gerry
L1 Certification Help was created by Gerry
Hi All,

I restarted rocketry the first of this year after several decades. When I was young I only ever did low power, but I've been working my way up and I'm now planning on launching a T-LOC 4 on a G77 at August 12th launch. The T-LOC is the 30th rocket I've built since January 1st this year. I'm obsessed!

I think I'm on track to go for an L1 certification attempt this fall, and I have questions:
  1. Is it safe to assume Amesbury is the site where I can attempt an L1 cert.? I know Acton isn't, but not sure about Amesbury.
  2. Should I join NAR or TRA? I guess I'm looking for recommendations and/or pros and cons.
  3. Are there members of the club willing to be part of the Certification Team? And how much do I need to pay them? (ha ha)
  4. I'm planning on building the Apogee Zephyr. By all accounts it's a great L1 cert kit, but if their are other opinions I'd like to hear them.
  5. More questions to come (probably).
Thanks in advance!

Gerry

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10 months 2 weeks ago #11781 by KennB
Replied by KennB on topic L1 Certification Help
Hi Gerry,

Sounds like you're stepping along nicely toward L1. Here's my shot at your questions:
  1. The Amesbury field is L1 suitable depending on the wind conditions. If the wind is out of the east, we don't do any high-power launches or even low- or mid-power ones if they would over 1000 feet; this is an agreement we made with National Grid after hanging a rocket on the wires (Seabrook nuclear plant 234,000V lines) a few years ago. It's best to have a good computer sim of your attempt under various wind speeds.
  2. CMASS is a NAR section so, of course, we'd suggest joining NAR. If you plan to do nothing but BIG down the road, TRA may be something to consider then.
  3. Lots of club members are L1 and L2 certified so there will be plenty of people who can check you in and witness your attempt.
  4. There are lots of options for L1 flight certification. If the wind is blowing in the right direction or nonexistent, you can fly most anything for the attempt. A rule of thumb says to use a 4" diameter rocket that weighs 5 pounds with motor and fly it with an H in the low 100's average impulse. it will go about 700 to 800 feet and, most importantly, land on the field.
  5. Ask away. You'll find lots of information and opinions available.

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10 months 2 weeks ago #11782 by Gerry
Replied by Gerry on topic L1 Certification Help
Thanks for the response Kenn. Big help!

The one thing that has me really thinking now is the idea of a 5 lb. rocket. Keeping the flight under 1000' is an excellent objective, but the Zephyr at 44ish oz on an H (9-10 oz) is going to go 1700-2000'. That would not be good. So I really need to reconsider which kit to build.

Thanks again. Likely will have more questions.

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10 months 2 weeks ago - 10 months 2 weeks ago #11783 by DeltaVee
Replied by DeltaVee on topic L1 Certification Help

Thanks for the response Kenn. Big help!

The one thing that has me really thinking now is the idea of a 5 lb. rocket. Keeping the flight under 1000' is an excellent objective, but the Zephyr at 44ish oz on an H (9-10 oz) is going to go 1700-2000'. That would not be good. So I really need to reconsider which kit to build.

Thanks again. Likely will have more questions.

My L1 rocket (3.1" dia Cherokee G upscale) was rigged for dual deploy.  However I used motor deployment plus a chute release... I set it up so that it carried everything that dd would require i.e. altimeter, battery, drouge, main etc.  It came in at around 53 oz. (~3.3 lbs) ... Somewhat more when loaded with an H165 reload/motor.  It reached (according to the altimeter) 1047 feet.  It happens that the day was so calm it probably didn't need the chute release.

Setting things up for dual deploy with the requisite altimeter and battery, bulkheads, charge wells, and other hardware will add a lot... at least 10-12 oz. , perhaps more.   Plus your be able to do that high altitude flight in the future!   I hope to actually fly a duel deployment when we return to Amesbury... But for sure it won't be a high flight this time either

It's not hard to build it heavy ;-)

 
Last edit: 10 months 2 weeks ago by DeltaVee.

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10 months 2 weeks ago - 10 months 2 weeks ago #11786 by Gerry
Replied by Gerry on topic L1 Certification Help
This is great stuff guys - thank you.  I did some simulations for the Zephyr and found I'd probably need to add a pound of weight to keep it to 1000 ft. (not quite sure how I'd do that...) I figured this would be a bad idea, but emailed Apogee just for yuks to see what they'd say. Yeah, they didn't think it would be a good idea either.

Now I'm looking at 2 LOC kits as options: The Yank Iris and the Mystic Buzz. Both are 4" rockets in the 4-5 lb. range and over 6' in length. I've run some sims and they look good, as in, there are H motor options that should safely get them in the 800-1000 foot range.
Mystic Buzz

Yank Iris

**Both of these have 54mm motor tubes, but LOC has adapters for bother 29mm and 38mm.

I'm sure there are reasons that these kits are bad options so let me hear them!

Also, how long are the clubs launch rails? For simulation purposes I've assumed 6' but I think they're longer.
Last edit: 10 months 2 weeks ago by Gerry.

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10 months 2 weeks ago - 10 months 2 weeks ago #11787 by DeltaVee
Replied by DeltaVee on topic L1 Certification Help

This is great stuff guys - thank you.  I did some simulations for the Zephyr and found I'd probably need to add a pound of weight to keep it to 1000 ft. (not quite sure how I'd do that...) I figured this would be a bad idea, but emailed Apogee just for yuks to see what they'd say. Yeah, they didn't think it would be a good idea either.

Now I'm looking at 2 LOC kits as options: The Yank Iris and the Mystic Buzz. Both are 4" rockets in the 4-5 lb. range and over 6' in length. I've run some sims and they look good, as in, there are H motor options that should safely get them in the 800-1000 foot range.
Mystic Buzz

Yank Iris

**Both of these have 54mm motor tubes, but LOC has adapters for bother 29mm and 38mm.

I'm sure there are reasons that these kits are bad options so let me hear them!

Also, how long are the clubs launch rails? For simulation purposes I've assumed 6' but I think they're longer.

Interestingly, I considered the mystic buzz myself, but cheapskate that I am, I went with the upscale Cherokee I got as a limited production kit as it came with all the parts I needed except for the electronic stuff.  The mystic buzz is a nifty looking rocket, and about the only drawback might be the split fins in terms of construction... But a minor issue at best.  The IRIS is a subject I really like because I like sounding rockets.  

Rails on the HP pads are available of course... 4" dia. can use 1010 buttons/guides.  I think we have 8' rails if I'm not mistaken.  All that matters I suppose is that the rocket is moving 30-40 mph when it leaves the the rail.
Last edit: 10 months 2 weeks ago by DeltaVee.
The following user(s) said Thank You: Gerry

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