Simplest Level 1 Certification bird I could build

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I will be down at MDRA this weekend - Good luck!

Looking at the weather, very much recommend getting this cert flight done on Saturday. Looks like we are going to have one of those extremely rare MDRA no wind days! In the past 5 MDRA launches, I can only think of one day that had wind less than 10 MPH. I am crossing my fingers for the weatherpersons to be correct.

Sunday, it is supposed to get back to normal. 10 MPH and clouds.
 
OP: I like that you’re going simple. Yesterday I signed a certification form for a guy who flew an even simpler flight. It was an Aerotech Initiator on an H128. Popped the chute at the top. Sky was clear and we watched the entire flight with our naked eyes. It landed maybe a quarter mile away and he walked out and picked it up. Super simple. I congratulated him on his judgement for flying a simple flight instead of trying to make it something more than it was and told him welcome to high power.
 
OP: I like that you’re going simple. Yesterday I signed a certification form for a guy who flew an even simpler flight. It was an Aerotech Initiator on an H128. Popped the chute at the top. Sky was clear and we watched the entire flight with our naked eyes. It landed maybe a quarter mile away and he walked out and picked it up. Super simple. I congratulated him on his judgement for flying a simple flight instead of trying to make it something more than it was and told him welcome to high power.

Now I'm trying to modify an existing PML Bull Puppy to only go 1000 feet with a J - lead in the nose, what else?
 
Now I'm trying to modify an existing PML Bull Puppy to only go 1000 feet with a J - lead in the nose, what else?
Lead in the nose is a terrible way to regulate altitude. The dynamics after ejection are completely different. The stability margin goes so high that you end up weathercocking too easily. Instead go fo lower impulse motors and higher drag rockets.
 
Lead in the nose is a terrible way to regulate altitude. The dynamics after ejection are completely different. The stability margin goes so high that you end up weathercocking too easily. Instead go fo lower impulse motors and higher drag rockets.
Not if you put equal weight in the tail cone, yes?
 
Not if you put equal weight in the tail cone, yes?
That would certainly solve the overstability problem. But I think the idea is that you're better off just using a more appropriate motor rather than trying to handicap the rocket like that. If you're doing a cert flight that requires a minimum impulse, then use a rocket that is more appropriate for the motor.
 
Not if you put equal weight in the tail cone, yes?
That wouldn't be optimal. You're better off using something other than lead and if you must add it somewhere, add it near the CG so it doesn't affect stability. A very heavy nosecone can pull a rocket to a certain ballistic death that might otherwise have descended in a flat spin otherwise. It's stressful for the shock cord, hardware, and glue joints. Weight can be useful, but drag or impulse reduction are the easiest ways to limit altitude. A lightweight rocket will fly faster, but that results in exponentially more drag. When thrust ceases it will slow down quicker because it has less momentum. A heavy rocket (similar to a Loki Dart) with retained momentum may actually coast farther.
I would go up in scale to a larger diameter, 4 inch or 6 inch, keep the rocket light, and use the smallest J motor that I could buy.
 
That would certainly solve the overstability problem. But I think the idea is that you're better off just using a more appropriate motor rather than trying to handicap the rocket like that. If you're doing a cert flight that requires a minimum impulse, then use a rocket that is more appropriate for the motor.

I agree on using a more appropriate rocket. I have a 6000 waiver to deal with, and I have to use a J
 
Gosh darn I do NOT like buying kits. Scratch is my thing, 38mm body tube is my obsession
It would be easy to scratch build a 4 inch or even 6 inch AGM-12 using cardboard tubing. I'm sure LOC, PML, or Binder Design would cut the fins for you. Just upscale the kits you're already looking at in Open Rocket. It would be a fun project and you would have a great sense of accomplishment.
 
It would be easy to scratch build a 4 inch or even 6 inch AGM-12 using cardboard tubing. I'm sure LOC, PML, or Binder Design would cut the fins for you. Just upscale the kits you're already looking at in Open Rocket. It would be a fun project and you would have a great sense of accomplishment.

I hate when other people are right. Thanks Steve
 
I flew this for my cert flight Saturday. I built it about 20 years ago, I just never got up the gumption to cert. It's 54mm with a 29mm motor mount, phenolic with plastic nose cone. TTW ply fins with square leading edges. I flew this a *lot* on a paved parking lot (many, many G80's). Occasionally it would come back with a tangled chute (or other problem) and smack hard on the pavement. On one bad landing, it popped out a fin sideways, and ripped out a section of body tube. I was able to glue everything back together and you can't see where it broke unless I point it out. I think I'll make another like it except with 38mm mount for L2 cert.
 

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I flew this for my cert flight Saturday. I built it about 20 years ago, I just never got up the gumption to cert. It's 54mm with a 29mm motor mount, phenolic with plastic nose cone. TTW ply fins with square leading edges. I flew this a *lot* on a paved parking lot (many, many G80's). Occasionally it would come back with a tangled chute (or other problem) and smack hard on the pavement. On one bad landing, it poppod out a fin sideways, and ripped out a section of body tube. I was able to glue everything back together and you can't see where it broke unless I point it out. I think I'll make another like it except with 38mm mount for L2 cert.
Cant see the pic
 
I like like to up size the motor mount in every build that allows it. I use an adapter most of the time, but when the air is still and my friends are cheering me on, bye bye adapter lol
 
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