Post a sim file, and how did you reach those numbers. Most any cardboard rocket will fly fine on most L2 motors that are not extreme high thrust or that push the rocket supersonic...you mileage may vary...
The rocket will most likely be a fair bit heavier due to the epoxy and electronics that I am going to install, so I should probably be fine.
Alright thanks, I treat my rockets pretty well during transportation.
Aint no way its going to weight that little, it should push 4.5 to 6lbs finished weight, depending on lots of things that aren't included, that add up quickly, like harnesses, hardware, batteries, electronics, avbay sleds, epoxy, paint, primer, all that stuff is going to add more mass than you think it will. However that motor will still fly that rocket nicely, and Redline motors are some of my favorites.
Build the rocket first...then size everything else to match...like recovery and motor, but have an idea of what you want to accomplish. Sims help you to sort of match your idea to the finished product. You may also find that the rocket needs a smaller or larger chute than you originally planned, better to buy it once rather than twice, though if you fly rockets long enough eventually you have lots of chutes in many styles and sizes, as well as harness, hardware and others stuff.
It is, I’m only launching it on I’s and small J’s.
I treat my rockets like babies, except when I send them hurtling into the sky. Thanks for the help.
Keep as light as possible and don't glass the tubes. I have a 3" cardboard scratch built that flies on Is and 6 and 7 grain 38mm EX J motors. It stays under 5000 ft. and has no issues being just cardboard.
That’s interesting. I’m not necessarily going for height, I just want something that I can launch over and over again. I might consider glassing it. Besides, that’s part of the fun!
That's one of the reasons I glassed the L2 cert rocket. I had never glassed tubes before and I wanted to learn. I know most folks say to keep it simple, but I used my cert rockets as learning opportunities. I used techniques and processes I had never used before when I built them. My L1 was my first DD, made my own nose cone, rolled my own coupler for the av-bay, scratch built everything but the MMT. My L2 was glassing tubes, tip to tip glassing of fins, foam filled fin can, and a zipperless fin can design.
I feel the same way as you about simplicity. I'm running a redundant dual deploy setup, I'd rather dish out a little money for altimeters I can use throughout my whole hobby than watch my 200 dollar-ish rocket that I spent weeks working on smash into the ground.
I understand what your saying, but I'm not sure that is really the situation. I never used dual altimeters until I built my L3 rocket. Other than the L3 rocket, I flew single altimeters in all my DD rockets for 10 years and the only one that crashed was my L1 cert rocket. That was early on when I only had one altimeter and swapped it between rockets. I had an issue with a L2 rocket that landed under drogue because the main tangled. I moved the sled to the L1 rocket without changing the battery because everything beeped out good. I suspect a connection in the battery had broken and the L1 rocket lost power and reset under thrust so it lawn darted. It wasn't a problem with the altimeter because after testing, I'm still using that altimeter as the primary in my L3 rocket with 14 flights on it.
Hmm, interesting. Maybe I’ve just been indoctrinated by my L1 “mentor/coach.” He’s a very avid fan of redundancy, and suggested RDD for both the main and the drogue for my L1 rather than just traditional DD with a drogue motor deploy backup. You are right, the probability of an altimeter actually failing is very low, the error lies in the construction. Now the thread is turning into a DD thread! Back to the rocket, if I have a 4” avbay, would it be worth it to run RDD just for the extra maybe 1% success chance that I get?
So basically, you are saying that the fact that there is a spare system is what makes it safer, not the fact there is another altimeter. Makes sense, altimeters very rarely fail on their own.
On my last DD flight my main got a little stuck in the tube, but came undone eventually. I believe it would be helpful to have RDD.
Smart man...
What makes that traditional?
Absolutely. BTW....how was the 1% calculated?
The spare "system" would not exist if it was not for the fact that there is another altimeter.
1. I agree, he is L3 certified.
Oh yikes I didn’t even think of that, I’ve never had a motor chuff. I’m debating whether or not to use motor eject now. I think it should be fine though because I will drill it to apogee+a few seconds, so if it does chuff it’ll eject at apogee or a few seconds before. However, two e matches should be more than plenty to deploy my drogue. Currently I’m leaning towards no motor ejection.
