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Welcome!
An ambitious build. Should be a fun flight!
Have you got your own ignition system for all that juice, or are you flying with club equipment?
Have you got your own ignition system for all that juice, or are you flying with club equipment?
I do not have any ignition system test as of now, just been enjoying the build while researching as much as I can. I have a small Estes PS II launch controller that I have used for my smaller first rocket, didn’t think it would have enough juice for when I work my way up to larger cluster combinations on the Ultimate, any recommendations on ingnition systems?Today I will be installing the rail guides and touching up on the fin fillets
Williamhimka
Well-Known Member
Sweet!
Welcome to the forum, Cwalk225! This is a great place to explore. And welcome to the hobby, there's plenty to keep you busy and keep your bank account empty.
Nice looking Ultimate, we love pics, post more as you continue! Pics of the Explorer would be welcome, too!
If you're just starting out, you may not be aware that the Ultimate will almost certainly require FAA authorization and notice to fly. Two things potentially place it into the FAA's "Class 2 High Power Rocket" category:
-Rocket weight over 1500g / 3.3pounds
-Propellant weight over 125g
Exceeding either limit moves the rocket into Class 2 status, and into the FAA's realm of interest.
Rocket weight includes motor, recovery system- everything that leaves the launch pad.
Propellant weight is listed on the motor specs.
If you have a large enough place to fly and landowner permission, you can request FAA authorization on your own.
The easiest thing to do is to fly big stuff at a club launch, most all of them have the FAA regulations covered, and you don't even have to think about it. They also have all of the launch equipment you'll need, and you'll get to see lots of other flights to entertain yourself while getting your rocket ready to fly.
I'm not trying to complicate things for you or be the Rocket Police, it's just part of the hobby as rockets and motor get larger.
Search the Ground Support forum for "launch controller", and you'll find some suggestions. The biggest issue with cluster ignition is available current. Using LiPo batteries or small lead acid battery like in a child's riding toy would help with that. I prefer 12 volts. The safety and launch witches in the controller will need to handle a fair amount of current for clusters. I'd expect a couple of amps per igniter, but that's nothing more than my guess.
Here’s a few more of my pictures for builds, I do appreciate the feedback. Have already reached out to some local clubs for some mentoring and future launch of my Ultimate build.
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Nice job! Has the Explorer flown yet?
Yes it’s been launched about 5 times so far, first with Estes D12-3 and then with Estes E12-4 motors
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Strictly speaking, a rocket exceeding 125g of propellant or 1500g liftoff mass also requires a Level 1 HPR certification in addition to the the FAA waiver.
Average thrust more than 80 Newtons, combined total impulse of more than 320 Newton-seconds, single motor total impulse of more than 160 Newton-seconds, a hybrid motor of any size, or a motor with a sparky propellant also require high-power certification to fly, but exceeding these limits does not automatically trigger the requirement for a waiver.
See the chart and detailed explanation from Soar Rocketry.
https://www.soarrocketry.org/wp-content/uploads/2016/08/HPR_metric9c.pdf
Image here:
I believe that NAR and Tripoli differ in allowing whether they allow complex configurations in certification attempts but I could be wrong on that, it’d be smart to check with the certification team before committing to one.
The listed spec says that the rocket weighs 1566g. It may be suitable for flight as a Class 1 model rocket with a bit of tube trimming and underpowering, and it may be suitable for a certification attempt with a 29mm H in the central mount.
That said, I have not encountered a great deal of enforcement on the 1500g limit. I once put a very long 3” internal diameter tube over an Estes Big Daddy, installed a stuffer tube and a 29mm mount, flew it on G80s and called it The Big One. I didn’t think to weigh it but I’m almost certain it was overweight for a kid flying it prior to the creation of the Junior Level 1 program.
I’m also not going to be the rocket police here, I just wanted to provide the complete, clear rules to avoid confusion and say “please be careful”.
