Minimum Diameter questions

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Active Member
Sep 12, 2009
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Hello Fellow Rocketeers
i am building a 29mm minimum diameter Blackhawk kit from Wildman.
i am new to highend rockets and wanted to get a few opinoins on some areas of this rocket.
1. What should i use for an engine ? i would like to get a reloadable just not sure what is good. also how can i retain the engine safely and still have an aerodynamic rocket ?i was looking into cast rocketry's slim line retainerwhich uses a snap ring to retain the motor.... i'd like to keep it professional looking and not have tape wrapped around everything to keep it attached. I will be using a ejection charge for chute deployment and i would like to eventually use an I class motor in it.

2. Can this rocket be used to obtain level 1 certification ?
All personal opinion here, so take it with a grain of salt. :)

My rule for certification flights is to keep it as simple as possible. One thing that means to me is keep it low to ensure recovery. Another thing it means to me is build it sturdy, even overbuild it in some respects. For me, that rules out any minimum diameter kits. I wanted a good, solid, thru-the-wall fin mounting, non-electronic recovery, altitude around 1200 feet or so and a soft landing with an upsized chute.

Can you use the Blackhawk for an L1 cert? Sure. Is it the odds-on best choice? I don't think so.

I accomplished both my L1 and L2 this season with a PML Tethys. Great rocket for cert attempts in my book. If you decide to go for it with the Blackhawk, be sure and let us know how it goes, and good luck!

Congratulations on your Blackhawk and welcome to the Wildman family!

We've got a great discussion going on over in High power about this little stealthy bird that will give you alot of tips.

I think for a first good all around motor the 24-40 case with the F-24-7 reload fits the bill. You get 3 re-loads in a pack for 20 something bucks. It will hit between 2000 -2500 ft depending on the weather and wind and you will be able to see and enjoy the entire flight! I have flown it n a Estes D-12-3 so it can be done, but don't expect much of a flight. 200-300 ft. and make sure its a long rod or rail 4ft min. It will fly great on any E also to around 1000ft.
But stick a G or larger and get ready to rock. A large open field and tracker are highly advisable, for this little bugger is gonna scoot.

One of the advantages of it is low cost.... high flights!

Yes L-1 easy attainable on this rocket.BUT unless you got eagle eyes, once again a tracker[borrowed,rented, or bought is highly advisable]

Even on a small H motor 5,000ft is an easily attainable target.

Yes you can put several brands of retainer on it no problem, especially if it's one of your first rockets. Just make sure what ever you use will allow the use of an adapter if you want to use 24mm motors.

Masking tape retention is proven if done right and has been used for many years before motor retainers were around.

Also a tiny hole 1/16 drilled in a fin and steel wire wrapped around the nozzle or through a small hole drilled in the rear closure is another option.

What ever you do, try to think of the future down the road flights, so you don't rule out the possibility of sticking a big honk'in motor in it, by miscalculating your approach now. Good luck, you will Love this rocket!

It's an addicting rocket . Once you start flying it, you want to just keep putting bigger and bigger motors in it. You can't help it!