New threads and interesting conversations directly in your inbox. Sign up now and get a daily summary of the latest forum activities!
Discussion in 'Low Power Rocketry (LPR)' started by CoachSteve, Feb 26, 2018.
straight forward build
should go up a ways
I love it! This is the same MMT configuration as an Estes Commanche-3 (though that is BT50, I think). Three stagers like this are notorious for out of sight flights. What are you doing for recovery? I suggest streamers or an undersized parachute, unless you want to have a county-wide search area.
That is such a cool design! I'd love to see it fly!
When I get out to CRASH this summer this will be one I bring for sure
And undersized parachute is the plan
For a light three stage, I would consider a streamer instead of a chute.
That top stage is 1.5" by 30" plus 8" nose cone - not sure a streamer will let it down safely - maybe a 2" x 5' streamer
What does the sustainer weigh with a used motor?
Right at 100g
That's a neat looking rocket!
I -personally- wouldn't use a streamer on this size rocket. The ideal solution would be a Jolly Logic Chute Release- yes it will fit, just barely. I fly a 38mm rocket with it fairly frequently. If you don't have one, a small parachute should be fine.
That said, I've had similar airframes to this fall from 1000' after the shock cord broke and be undamaged. It's up to you- some rockets fall differently than others, so use whatever works.
By the way, I vote F44W to D21T to D10W with onboard timers. MOAR POWER! :wink:
That's a bit more than I was planning
bet it would get up to a pretty good velocity - I think I am going to open rocket it to see just how insane that would be
The forward and back sweep between booster1-booster2-sustainer is cool!
Will it go on C11-0 to A8-0 to A8-5? Will keep your staging in visual range, cut down walk to find the boosters and the sustainer.
I might try an evil twin of yours, difference is reverse sweeps. Booster1 forward, booster2 back, sustainer forward.
This puts a forward sweep on the sustainer. Advantage is since the sustainer lands tail first, with a forward sweep the impact point is engine casing not fin tip. Cost is fins slightly less effective (center of pressure a tad more forward with forward sweep.)
Like your spiral tape. Is that electrical tape or something else?
Evil twin - cool.
The spiral is vinyl automotive pin stripe (super cheap on ebay)
Depending on the day the first launch will be powered accordingly (super calm day this baby is going for the stars )
I do enjoy seeing the deployments over sheer altitude though so i may take your advice
Out at CRASH I launched several Comanche 3's D12-0 C6-0 C6-7 and have recovered all the stages. Use a long Mylar streamer/chute that glints in the sun. Good weather and a good eyes crew on the second stage is the key.
If you go with chute AND you have space for it in addition TO the chute, a long Mylar shiny streamer (even a thin one) can help visibility both on descent AND if it lands in bushes or tall grass, even if it is not your primary recovery device.
To the moon
I'm with you there; I always like interdigitated fins. How about a not-so-evil step brother with forward swept first stage fins, rear swept sustainer fins, and second stage fins that look like a K against the body tube? Something very roughly like this:
What were motors?
Was everything recovered intact?
D12-0 - B6-0 - B6-6
Lost the sustainer this day - we believe it landed in the lake - I had a very small chute too - still drifted way too far -
looks like a rebuild is in order
Too bad about the sustainer loss, but since you're smiling at the prospect of a rebuild, I guess it's not too too bad.
Ha - it was just a couple sections of tube and a nose cone - no electronics fortunately (although had i used my chute release i may have gotten it back
I see an A8-5 in your future!
So - a lost sustainer cant keep me down forever - final stage is getting a rebuild, this time a little Ram-Jet style
It will fly again
Nice! And a little extra drag to boot to (hopefully) keep it around for more flights.
A little nicer weather and it will get paint and be ready for flight at CRASH this summer
Ready to fly:
I’m a’wonderin’ if that ramjet nose may be a bit more draggy than you think.....
I lot of drag is fine by me - as you remember, the first sustainer was lost to the cloud gods
I was thinking more stability issues. You have plenty of tail plumage, but you are also going to have a lot of mass with three motors in the tail. In the rockets favor, it is a very long rocket. It’ll proooooobaaaably do fine, definitely going to ge a heads up launch, the mid section booster is going to stage high and be hard to track.
You gonna go full three stack on first flight, or go onesie twosie threesiee?
full stack for sure
@neil_w would be a better source for this, but I question the reliability of ORK (or any SIM program) to calculate the CP shift from your ramjet nose.
Also not sure of the effect of your fancy mid-body chamber on CP
That said, due to the length of the rocket you have plenty of calibers to spare to start with, so you will probably be okay.
Hope you get three straight trails, three short walks, and three soft landing.
Separate names with a comma.