Hey I am new Im guessing this is how you post something but that is the question I had. What motor would lift my 4 pound rocket Or do I need to do 2-3 Motors for my Rocket Without need Certification so like anything 80 Newtons or less. I am just in need of help here Thank you guys.
Does anyone know what motor Or Maybe a motor cluster would work to lift a 4 pound rocket.
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You want to launch a 4 pound rocket without any certification?
boatgeek
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You'll need an L1 to launch a 4-lb rocket in the US. The highest you can go without an L1 is 1500 grams (3.3 lbs). You'll also need an FAA waiver if you go over 1500 grams, which basically will require flying with a club. The club will almost certainly enforce the L1 limit.
If you back it down to 1500 grams liftoff weight, you'll need a total of about 75N initial thrust for minimum speed off the rail and no more than 80N average thrust to stay under the L1 limits. Any of the high-thrust Aerotech 29mm Gs (G76, G80, etc.) would work, or if you want to go a little lower, the Cesaroni 24mm F79 would be fun. At your apparent level of expertise (not a slam, just what we know so far), I'd suggest a single use motor or an Aerotech LMS motor. Those are quite a bit easier than the other reloads.
If you back it down to 1500 grams liftoff weight, you'll need a total of about 75N initial thrust for minimum speed off the rail and no more than 80N average thrust to stay under the L1 limits. Any of the high-thrust Aerotech 29mm Gs (G76, G80, etc.) would work, or if you want to go a little lower, the Cesaroni 24mm F79 would be fun. At your apparent level of expertise (not a slam, just what we know so far), I'd suggest a single use motor or an Aerotech LMS motor. Those are quite a bit easier than the other reloads.
DuctTapeandRocketFuel
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Any rocket weighing more than 1500 grams including motors and/or 125 grams of propellant is a class 2 rocket, and requires HPR certification (at least in the USA.)
BoatGeek
Thank you for the reply That makes much more sense and I Think I should work on getting certified. I just wanted to see if it was possible but I think its Clear I need To get certified. also 4 pounds I need a FAA waiver so no can do for now
Thank you for the reply That makes much more sense and I Think I should work on getting certified. I just wanted to see if it was possible but I think its Clear I need To get certified. also 4 pounds I need a FAA waiver so no can do for now
The weight limit to stay out of high power is something I forgot in replying to your other thread with the same question. (By the way, repeating like that is not a good idea.) So yeah, get certified. No time like the present. Well, whatever future appropriate club launch closest to the present.
Will Do ( sorry about the other post I delete it). Question By the way Do you know how to calculate how high the rocket will go using weight and what type of engine to use. I have openrocket so Maybe should use that.
Yes, you should definitely use that. I can show you the equations I used in the other thread, but they are really rough because they assume no drag and zero burn time; that is, impart all the motor's impulse to the rocket at once, divide by the mass to get the initial speed, then ignore drag, and computing the apogee isn't hard. But it's also quite a bit too optimistic, and when you've got a better way, like the numerical simulation performed by OR, you absolutely should use it.
Thank you so much I have been looking everywhere. Drag Causes A major factor A Physic teacher was helping me solve a equation once and got 30,000 Feet in reality Its about 3000 feet.
Yeah but that would be awesome if you shared those equations. I tried a lot of places and am currently testing my rocket it open rocket but still want to understand how the math behind finding that stuff out works!
What is your level of knowledge in physics and math? That will let me avoid either talking down to you or going over your head.
I'll be able to answer tomorrow, but am now going off line for the night.
I'll be able to answer tomorrow, but am now going off line for the night.
Do not know to much about pysichs I would say Im on a scale of 1 out of 10 for knowing I would say im about a 4.5
What I wrote in Word didn't paste well into a reply, so open the attached. Maybe I'll try to get it looking good in forum text later, but I do not have time now.
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