L-1 cert ?

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Andy Greene

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I was going to ask over on the HP section- but didnt want to get too ripped to shreds , so I will pose my question here instead :rolleyes:
So I was reading a thread over there that that had some references to successfully obtaining an L-1 with a PSII kit. I know , I know- there ARE better options , but a DD bird is not in the cards right now. I have successfully flown my Argent at least 7 times on a G-40/9W with the only issue being a motor cato that the rocket survived without damage. Soooo , that said-

1) Has anyone here done it ?
2) What did you fly it on to keep it at or lower than the altitudes I achieved with the G40 ? (that was plenty with a little breeze)

When I do get a chance to fly MP its at Tripoli Tampa - so there is a good bit of room.
Advice and input welcome- Im just gonna step over here and put my flame suit on :wink:

Andy
 
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Your peak altitude is a direct function of the total impulse of the motor installed. So, by definition, an H motor will take your rocket higher than a G motor will. You can limit the maximum altitude that the rocket will achieve by using the smallest motor possible, or by using a faster burning motor, since drag losses go as velocity squared.

The smallest H motors from each manufacturer are the CTI H133BS (163 Ns) and the Aerotech H165R (165 Ns). These are both significantly more total impulse than in a G40 (97.1 Ns). Your rocket will go very high on either of these motors. It is certainly possible on a large field with many observers, but if you are uncomfortable performing such a flight, better to build another rocket and use that for the certification.

Besides, you'll want to build more rockets in the future anyway, yes? Better to do your cert with something that you're comfortable flying so you can do so over and over again, rather than potentially losing everything for one shot at it.

Best of luck either way :)
 
No flame suite needed. (And I'm sorry it seems necessary...)

You're right, there is no need to do dual deploy for L1. In fact, many people will advise against it so as to keep it simple; fewer things to go wrong on an L1 flight.

The purpose of an L1 cert is to demonstrate you can build a rocket that can safely withstand the stress of high power flight and recover it safely. For my L1, I built a simple 3FNC out of Blue Tube. Using a small 'H' motor it flew to about 2,500', and recovered within less than a 1/4 mile walk. Some folks prefer slightly heavier, 'low and slow' flights so that they don't have to do DD or walk too far for recovery.

I hope this helps.
 
David gave you some great info.

Me? I just moved your thread to the HPR section. The natives will behave themselves. :)

-Kevin
 
David gave you some great info.

Me? I just moved your thread to the HPR section. The natives will behave themselves. :)

-Kevin

All good Kevin :wink: ,
and thanks for the replies- Sound advice David, thank you.

I dont suppose my MC Mozzie 2.6 would be any better option would it ? On a G33J-5 they show it at 1600 -so I'm guessing not but I gotta ask.
Besides I already have 2 built- lol
I really really suck at using the calc- sorry for the newb questions.

Suggestion on for a non DD- kit that wont break the bank- poss something that could later be upgraded to DD ? Low and slow is just fine by me btw- but open to suggestions.

Andy
 
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You won't necessarily need DD to get your rocket back. Running a quick and dirty sim using thrustcurve.org's Motor Guide tool, it looks like an Argent goes about 1500 feet on a G40W, and will go about 2200 feet on either of the aforementioned H motors. The H410VM, despite its higher total impulse, achieves less final altitude than the H133 due to the increased peak velocity, but not by much.

2200 feet with single deploy is very manageable; have some experienced flyers help you track it with binoculars and get a careful line on where it lands, and you should have no issues getting it back as long as your field is large enough. In the desert, I've flown single deploy rockets to 10,000'+ and recovered them successfully without a tracker. In the humid Florida air, you'd probably have trouble seeing something that high, but 2200' should certainly be workable.

If you want to go lower and slower, the easiest way is to increase diameter, since drag also goes as diameter squared. Pretty much any 3" or 4" cardboard kit will do just fine on a variety of H and I motors-- Madcow and LOC have several. (Protip: a LOC Caliber ISP is basically a LOC Forte with a 54mm motor mount and a payload section for only $7 more. You can build it and fly it single deploy with a 29mm or 38mm adapter for L1, then add the payload section for dual deploy capability and fly to ridiculous altitudes on 54mm motors once you get some more flying experience!)
 
I dont suppose my MC Mozzie 2.6 would be any better option would it ? On a G33J-5 they show it at 1600 -so I'm guessing not but I gotta ask.

I would suggest it. The biggest reason being that velocity and long thin fins like that are a bad combination. If you get any fin flutter, they're susceptible to breaking off, and that means not only no cert, but worse yet, a ruined rocket.

I really really suck at using the calc- sorry for the newb questions.

If you're using any of the simulation software, it takes time to master. Trust me, we've all been there!

Suggestion on for a non DD- kit that wont break the bank- poss something that could later be upgraded to DD ? Low and slow is just fine by me btw- but open to suggestions.

David has given some great suggestions. If you like Mad Cow (who doesn't?!) and it's within your budget, a 4" Frenzy is another good choice. It can easily be upgraded to DD at a later time.

-Kevin
 
depends on what your definition of break the bank is. I understand the 'Mega der Red Max' would work and not go over high. you would probably want something in the 4" diameter range...a Madcow patriot can be built single deploy and later modified for dual deploy w/o much work.
Rex
 
sorry- I failed to hit refresh before I asked- lol

Thanks guys- now just gotta convince the wife I need another rocket - lol
 
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David has given some great suggestions. If you like Mad Cow (who doesn't?!) and it's within your budget, a 4" Frenzy is another good choice. It can easily be upgraded to DD at a later time.

-Kevin

Damn thats a big bird ........
 
Damn thats a big bird ........

Big is relative. :)

You could also consider a 4" Super DX3

You'll notice I'm suggesting 4" airframes. The reason is that if you're talking about DD, my guess is you're considering Level 2 sometime in your future. On an H or an I, single deploy, you can keep the altitude low. But you can also easily move up to larger motors, if you choose to do so at a later time.

-Kevin
 
Damn thats a big bird ........

It is big, but it is very versatile! I did my L-1 on the Frenzy on a CTI H225 White Thunder. Motor eject. Didn't go more than 2000 feet at the most. Building it was just like building an estes PSII (or LPR) rocket - paper tubes, plywood fins and it was fun! It was an awesome flight on a great rocket.

The price is excellent and upgrading it to dual-deploy is pretty simple. In my mind, the only drawback is that you need to buy some smaller items separately. If you want a complete kit, don't forget our friends at Binder design.

Always keep in mind that one should pick rockets THEY LIKE to build and fly. There are so many different designs and types - do what makes you happy and that makes the whole thing even better.
 
Always keep in mind that one should pick rockets THEY LIKE to build and fly. There are so many different designs and types - do what makes you happy and that makes the whole thing even better.

+1

Totally agree. While we might make suggestions, ultimately you need to buy the rocket that makes you happy.

-Kevin
 
Thoughts on the Batray or maybe a Tembo ?
Never mind- just realized neither is DD upgrade capable later.
Gonna sit down and play with the sim and figure out what I really want to do and can afford-

Thanks for the info and tips, more are welcome.

Andy
 
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Thoughts on the Batray or maybe a Tembo ?
And yes David- I like the idea of keeping it upgrade able later .

I'm sensing a theme, here - you like stubby rockets. :)

Personally, I'd go with the Batray over the Tembo.

The reason is that I've seen rockets like the Tembo go unstable with Level 1 range motors. Better to have something a bit more on the long & thin, which is more likely to be stable.

Others may disagree with me.

(And yes, I think the 4" Batray is an even better choice. But I doubt that surprises you. ;) )

-Kevin
 
I'm sensing a theme, here - you like stubby rockets. :)

Personally, I'd go with the Batray over the Tembo.

The reason is that I've seen rockets like the Tembo go unstable with Level 1 range motors. Better to have something a bit more on the long & thin, which is more likely to be stable.

Others may disagree with me.

(And yes, I think the 4" Batray is an even better choice. But I doubt that surprises you. ;) )

-Kevin

Im only 5'5 - its a complex issue- :lol:
Its really cost that is driving me- ( I know I know) AND I can ALMOST justify it to the wife- lol .
Plus I like the look of the Batray. The Patriot is a close second.
 
If it's got a 29mm hole, it'll work. 2,000 to 2,500 isnt too bad for a single deploy if you have the space and weather. Load up and go for it!
 
I'm planning on getting a Binder Design Excel DD that can be used either DD or shorter single.
Here is a picture of the rocket in both configurations. https://www.rocketryforum.com/showthread.php?56182-L2-Build-Binder-Excel-Plus&p=726656#post726656

There are many build threads here on it I just picked this one out because it showed it both ways.

I am planning to use my GForce for level one and the Excel for L2 but I could use the Excel for both if I want.
I'm getting the 54mm version with a 38mm adapter for the Excel and my GForce which is 29mm will go up on an "H"

Good luck whatever you do and you will find a lot of good folks here that will help... I did.

Ed
 
I'm planning on getting a Binder Design Excel DD that can be used either DD or shorter single.
Here is a picture of the rocket in both configurations. https://www.rocketryforum.com/showthread.php?56182-L2-Build-Binder-Excel-Plus&p=726656#post726656

There are many build threads here on it I just picked this one out because it showed it both ways.

I am planning to use my GForce for level one and the Excel for L2 but I could use the Excel for both if I want.
I'm getting the 54mm version with a 38mm adapter for the Excel and my GForce which is 29mm will go up on an "H"

Good luck whatever you do and you will find a lot of good folks here that will help... I did.

Ed

Thanks Ed- I really like the look of that model. The more I look at the Batray- its just not me, and I know you guys cant "tell me " what I like- but the suggestions are helping.

Honestly David I cant ever see myself wanting or affording an L-2 bird. That said , what are thoughts on going with a 3" rocket instead-
I love the look of the Aerobee 150A , but with dinner cooking I have not had the time to play with sim to see if thats gonna be a stretch on SD .
Its DD capable and I LOVE the look, cost is right as well.
 
I got my L1 cert on the Binder Design Excel. It was a fairly easy build and is a forgiving rocket. Flow it several times since the cert flight, some of them not very pretty (partially collapsed chute on the last flight) and it has always come home in one piece. You can buy the basic kit and add the dual deploy material at a later time, if that makes the money work better.
 
Or scratch build something . Word of wisdom go up to a bigger hole 54mm it's cheaper to adapt down
 
Honestly David I cant ever see myself wanting or affording an L-2 bird. That said , what are thoughts on going with a 3" rocket instead-

3" is 'better' than 2" -- it's easier to keep the altitude down, especially if you decide to play with bigger motors.

FWIW, "I can't see myself..." is Famous Last Words at a rocket launch. :)

-Kevin
 
3" is 'better' than 2" -- it's easier to keep the altitude down, especially if you decide to play with bigger motors.

FWIW, "I can't see myself..." is Famous Last Words at a rocket launch. :)

-Kevin

LMAO :cheers:
 
I'll also vote for the Super DX-3 (4" paper and wood version). I got my L1 and (after modifying for dual deploy) my L2 with that rocket. It's a workhorse and a good, straightforward intro to the HP part of our hobby.
 
This is a great thread for sure!

I have to agree with Kevin "I can't see myself....." is really where things start. Because the seed is planted. I never thought I'd get a L1 cert and here I am with my L2 wondering what I'm going to do for my L3 and when I'm going to do it. Famous last words for sure!

If you like shorter rockets....there are many which are fantastic. Here are a couple of popuplar ones:
LOC/Precision Mini Magg is a popular choice. 5.5" paper/ply. I have heard tell of people torturing the poor girl with a Loki J1000 on a stock build.
Aerotech Sumo is also a good L-1 option! 4" with plastic interlocking fins.
The aforementioned Estes ProSeries II Der Red Max is also a great flying rocket.
 
what are thoughts on going with a 3" rocket instead- .

When I was asking like you are now one of the recommended rockets that folks liked here was this 3" that has it all with no need to buy anyyhing else....well you do have to buy motors for it,, ha, ha....I just like the 4" size. That said I probably will get it as well somewhere down the road because I really like the way it looks and it has good reviews and recommendations

Vertical Assault
https://giantleaprocketry.com/products/kits_almost.aspx


Ed
 
FWIW if you can get a quick idea using trustcurve.org. Putting in a 3 in rocket at 34 ounces (from the web site) shows this bird will fly to about 1500 to 1700 with a large number of H motors. I would think you are well within range on that.

I would recommend you talk to members of your local club. Many are quite experienced with tracking rockets and can tell you if they are likely to lose track of your rocket. Don't push their boundaries unless you are prepared to track the thing down. If you want extra insurance you might also be able to borrow a tracker.
 
Unless you plan to fly a minimum diameter rocket you're unlikely to need dual deploy if you stick to Level 1 flying and your field is not really small. The fact that you want to upgrade to dual deploy is a pretty good indicator that you'll end up flying Level 2 rockets. You may not want to admit it now but that is where you're headed.
 
So many answers ... . Here's mine.

I gave this advice to someone recently who knew absolutely nothing about HPR and was a bit scared of it.

Buy something that can fly on G motors and build it. Instead of glue, use epoxy. Make sure your fins are strong and durable.

If it comes with a forward motor retention ring, leave it out. They will limit the size of the motor casing that goes in it to an Aerotech single-use motor.

Consider a nomex or pyrex chute protector. Definitely use rail buttons instead of 1/4" lugs. The rod whip off a 6-foot 1/4" rod can kill your cert flight. And you'll want to understand rail launch pads for the future anyway.

If it's good and strong, fly it a few times on G80. See how high it goes, how far away it lands, and how it survives.

Once you've done that, certify at a club meet on a baby H (see post above, H133 for example). If you can launch it and recover it on a G, you can do it on an H.

Voila! You are level 1. And, if you want to fly the same rocket at places where you don't have an FAA waiver, you can still fly it on Gs.

Rocket possibilies? Mega Der Red Max, Leviathan, Aerotech Sumo, Aerotech G-Force. With the G-Force, you need to modify the motor retainer clip so that it doesn't poke through the motor tube.

Good luck and have fun!
 
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