4 stage, 3-way cluster??? Future History

[stealth6]

So this one is a bit different.

It's either a 12 motor cluster, or a mega cluster 2-stage, or a 4-stage/3-way cluster. The paint just dried so it's time to post it here for your perusal.



Specs: 3" diameter by 45" tall, cardboard airframe, plastic nose cone, 3/32" AC ply fins. Two separate avionics bays - one in the nosecone featuring a Raven handling deployment duties, and another mid-airframe with timers handling the staging/airstarts. On the tail end there are three 24mm motor mounts that will take either BP or AP motors. And then the really special bit: nine 18mm motor mounts piercing the airframe and canted. Scratch/custom designed & built of course.

I designed this so that:
--- A) it can ignite all 12 motors at once off the pad - I would use all BP motors in this case. Total impulse in this configuration would be roughly equivalent to a G75/G76 (but of course with a fair bit more motor mass). Sims show an altitude of roughly 1200' maximum.
--- B) it can launch off the pad on the three 24mm motors, and then airstart all the 18mm motors for a second stage. In this case I'd likely use AP motors for the 24mm's (E18s up to F24s). Airstarting would be handled by a single timer in the mid-section AV bay. Total impulse here would be roughly equivalent to something between an H148 and an H180. I don't have the sims in front of me right now, but I think I remember altitudes in the low/mid 2000's.
--- C) it can launch the same way off the pad as in "B", but then the 18mm motors would airstart in groups of three each, for 4 total stages. This way will be a lot trickier, and will require three seperate timers (that is what those Galejs timers are for, Matt) or a timer that can handle three seperately delayed events. I've still got some work to do to figure out exactly the best way to do this. But internally it's already wired to be able to do this. If you look close you will see two set-screws next to each 18mm motor mount - these are what I attach the ignitors to (Q2G2s).

I had to build this a LOT lighter than my usual builds. This, coupled with the fact that my last few builds have been fibreglass (and therefore could be rough handled), meant that I really botched this build up aesthetically. I also had numerous accidents, poor design decisions, ham-fisted handling, and mistakes due to rushing along the way during the build. After a while I started saying "screw it, it's good enough" which of course didn't help. The upshot is that the build quality, paint & finish on this is very much a hack-job in my book. Definitely a "sixteen foot paintjob". Oh well, if it flies great I'll be happy.

I'll post launch reports (with pics and/or video perhaps) when it flies.

thanks for checking it out, s6

 

[TopRamen]

It's Jaw Droppingly AWESOME is what it is!!! Let's see it Fly!!!:clap::drool:

 

[Rich Holmes]

In my head, "staged" means it drops the spent motors (and the part they're mounted in) once they're done, so to me this isn't staged. What it is is (as I believe someone once said) jaw droppingly awesome.

 

[blackbrandt]

Didja get the timers? You never emailed me saying you did...
:rofl:

--- C) it can launch the same way off the pad as in "B", but then the 18mm motors would airstart in groups of three each, for 4 total stages. This way will be a lot trickier, and will require three seperate timers (that is what those Galejs timers are for, Matt)

 

[Astronot]

Maybe he means sequenced. Which is also awesome. I like the concept and versatility of it. That's an awesome looking rocket. We've got to see video and pictures of this thing flying.

David

 

[stealth6]

Yes, I got them. Thanks!

Only two of them have g-switches, and I'm trying to either get a third one or configure something for it. I've also been contemplating using trip-wire switches instead (yes, I know that this will mean I can't fly at group/public launches - not a big problem for me as I fly solo 95% of the time). I also have to replace one of the capacitors. As well, I have an unanswered question about the operation of these that I've been trying to work out. Since there will likely be a large deceleration between the stages (or "sequences" if you well), would that shut subsequent timers off? Or once they start their timing period (at lift off) will they fire at the end of their set time regardless of multiple acceleration/deceleration/acceleration events? I've also possibly got the use of a Xavien XFist 5-event timer that might work (or not) in this instance and that may (or may not) be better suited to what I'm trying to do. So, you see how I've "still got some things to work out" as far as multiple stages/sequences goes.

For now I'll fly it in configuration "A" and then "B". Once those go smoothly, I'll move on to attempting configuration "C". One step at a time.

s6

 

[gdjsky01]

It's Jaw Droppingly AWESOME is what it is!!! Let's see it Fly!!!:clap::drool:

:w::drool:oint:oint:oint:
What he said!

 

[stealth6]

I tell you what would be "jaw droppingly awesome" - flying this on all AP motors. F39s for the three at the bottom, and D24s for the other nine. Or F24s & D13s for all White Lightning propellant - would be a dang cool fireball off the pad for a "mid-power" rocket.

First, I'd have to come up with a LOT of 18mm cases. I do have three of them, and I've got three 24/40 cases as well. But that still leaves coming up with six more 18mm cases - yikes. Then I've got to find a team of minions to assemble all those motors for the launch (and clean them after the flight!). Then, I've got to come up with a way to light 12 AP motors simultaneously, EVERY TIME, with TOTAL confidence. No small feat. This last one I'm working on, and I've got a couple of very promising possibilities. I need instant ignition, plenty of spark, in a very slim/tiny ignitor, and lots of juice from the power source. But like I said, I'm working on this at the moment.

And again, like I said, one step at a time. First let's launch this all together with BP motors. That's going to be cool enough on it's own.

s6

 

[patelldp]

I tell you what would be "jaw droppingly awesome" - flying this on all AP motors. F39s for the three at the bottom, and D24s for the other nine. Or F24s & D13s for all White Lightning propellant - would be a dang cool fireball off the pad for a "mid-power" rocket. First, I'd have to come up with a LOT of 18mm cases. I do have three of them, and I've got three 24/40 cases as well. But that still leaves coming up with six more 18mm cases - yikes. Then I've got to find a team of minions to assemble all those motors for the launch (and clean them after the flight!). Then, I've got to come up with a way to light 12 AP motors simultaneously, EVERY TIME, with TOTAL confidence. No small feat. This last one I'm working on, and I've got a couple of very promising possibilities. I need instant ignition, plenty of spark, in a very slim/tiny ignitor, and lots of juice from the power source. But like I said, I'm working on this at the moment. And again, like I said, one step at a time. First let's launch this all together with BP motors. That's going to be cool enough on it's own. s6

www.valuerockets.com!

Three F39T's, three D24T's, and six D21's! Get it done!

 

[stealth6]

Maybe I should start a Kickstarter campaign to fund an all-AP launch.

s6

 

[marcusSRG]

That is badass dude! Well done!! Please keep us updated on this one. Flight pics will certainly be impressive!

 

[TopRamen]

An all AP Launch would be too fast to appreciate. I vote for atleast getting to see it once on BP.

Smoke! Fire! Noise!!!!

 

[Scotty Dog]

HOLLY MOLLY!!!!!!
That is the CATS MEOW!
:clap: :clap:
I love the colors.

 

[Aksrockets]

You never fail to impress, S6! Your "16 foot paint job" looks a lot better then my 2 foot!

Any chance of me seeing you at a launch sometime?

Alex

 

[stealth6]

Any chance of me seeing you at a launch sometime?

Alex

There's a chance I might come up for the February 15 launch. You going to be there?

thanks for the kind words,
s6

 

[Chrisn]

Are those screws on the side for some form of motor retention or are they to connect the igniters onto for airstarts?

 

[Scotty Dog]

Name?

 

[Dale Saukerson]

Now there is some unusual and creative cluster arrangment.
Great choice of scenery for the 1st photo too.
Would love to see some flight footage on this one.

 

[Coop]

Very impressive! Look forward to launch photos!


Later!

--Coop

 

[stealth6]

Are those screws on the side for some form of motor retention or are they to connect the igniters onto for airstarts?

The silver screws on the sides of the motor tubes are contact points for ignitors. These are wired internally to the mid-shaft AV bay. They are wired such so that all nine can fire at once, or they can fire separately in groups of three.
Motor retention is handled via a button-head screw (black in the photo). The motor mounts are 1/2" CPVC, which just happen to be a perfect fit for 18mm motors. The rentention screws are tapped/drilled into the lower ends of the motor mounts. The screws in the two uppermost mounts per side also extend just a bit more such that they act as an extra set screw into the motor below them.

Name?

My rockets always "name themselves". This one has yet to be forthcoming with the information.

s6

 

[rocketgeek101]

Do you have any photos of the internals of that rocket. I would be very interested to see.

Nice looking bird. That's definitely a unique design.

 

[Daddyisabar]

A good looking 12 motor park flier for the kids. It is just an ignition issue with a modicum of nose weight. Lots of smoke and a slower lift off from all those inefficient, heavy and canted BP motors. The old guys will love it. Then rip it off the pad on composite motors with hard rock blaring in the background for a totally SHWAG and hip experience for cool youngsters, and the chicks will love it!

 

[JeromeK99]

:eyepop:


Light that candle!




Jerome

 

[Verna]

>I'll post launch reports (with pics and/or video perhaps) when it flies.


Nice! You can't go wrong with a cluster.

:clap::clap::clap::clap:

Verna
www.vernarockets.com
https://www.facebook.com/RocketBabeDustStorm

 

[Threemorewishes]

Very nice.

 

[stealth6]

It worked!!! *

 

[stealth6]

* for the most part.

Took a bit of a road trip this weekend and attended Tripoli Las Vegas' monthly club launch at Jean Dry Lake in Nevada. I brought this rocket along to attempt its maiden flight. It was an absolutely perfect day for flying - mid/high 60's, totally clear skies, and dead calm. Enough folks showed up that made it fun to watch and experience everyone else's flights, but few enough that there was never any waiting to launch, and that was with only one rail pad available. Good folk & hospitality, cool rockets and propellant, lots to learn and share, awesome weather, and a big open dry lake bed to fly in - what more could you ask?

I promised a flight report once I put this rocket (now with a name by the way - "Future History") in the sky so here it is:

The GOOD - Well it flew of course. It actually flew great. For its first flight I decided to launch all BP motors at once off the pad. They all lit just fine (using Q2G2 ignitors), and the lift off was nice. It flew smooth and straight for an apogee of about 660' - not bad, I had simmed/calculated about 750-800' or so. The crowd enjoyed it, and I got a few decent photos as well. One cool "extra" was the ejection blasts - having twelve motors all fire their ejection charge pops together at such a low altitude was pretty neat, and kinda funny.

The BAD - First off, my motor retention scheme did not work out all that great. Fully eight of the twelve motors ejected from the rocket, causing a fair bit of damage (and an amusing rain of spent motors falling from the sky). The retention screws failed and came out. It's funny - I did ground test this pretty extensively in the design phase and it never was a problem - worked fine on the ground. It seemed though in the flight that the CPVC (which I used for motor mounts) heated up enough to soften which allowed the screws to pop out or twist out of the way. This will be pretty hard to fix as it stands. Second, the landing was hard enough to cause some impact damage - nothing huge (creased airframe and such), but enough that I can't fly again before repairs & modifications.

The UGLY - I guess that's gotta be me, but there ain't much I can do about it I suppose.

So, some post-flight thoughts and such:
The damage is all fixable, but extensive enough that it might be wiser to consider this a prototype and to move on to a better design. Which of course means abandoning this particular rocket, and building something new from scratch. I'd REALLY like to build something tougher (say, out of fibreglass perhaps), but the total available thrust I can load into this dictates that this rocket has to be VERY light. It's a bit of a conundrum. If it weighed any more than it does now, BP motors will not work. I'm not opposed to building this so that it can only fly on 18mm & 24mm AP reloadables, but then it's going to be pretty expensive to fly (not to mention having to assemble and CLEAN twelve motors for every flight). I'd have to somehow come up with six more 18mm cases too. Further thought will be necessary.
I also have to come up with a better motor retention plan. I liked the one I had, mainly for the clean aesthetics; and I don't want something intrusive/complicated/expensive, but it's obvious I have to come up with a better idea.

But it DID work, it DID fly, and it WAS pretty dang cool and fun. So, I'm pretty happy for now.
Onward to the next phase,
s6

 

[stealth6]

I had to build a cluster whip to get current to all those ignitors. It was pretty silly/ridiculous.



s6

 

[Rich Holmes]

Bravo!

 

[aerostadt]

Nice model and nice flight! I found on my Double Shuttle parts usually fit differently in the field than the did at home on the bench. I wonder if that is what happened. It looks like you used Q2G2 igniters. Rigtht? Did you have air-starts on this flight? If so, was it with Q2G2 igniters and did they hold in place on ascent?