I69 in a minimum diameter rocket?

Hello All,

Came across an Ellis Mountain I69-10 -- Interesting looking motor...

Anybody heard of/ seen flown / actually flown one of these in either a minimum diameter (29mm) or 38mm airframe optimized for "getting way up there" ?

I'm 0 - 1 in this department (Did a Vulcan I200 once in a 38mm x 4' ship and never saw it again) and wondering...

Curious, Andy

Reply to
Andy Eng
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I have one I was going to put in a beefed up Estes Eliminator. basicly the kit with a 29mm motor tube the whole inside of the estes kit.

I've flown it on Ellis G35s to almost a mile, even at LDRS-23, and wanted to try the H50 and then the I69 in it as well.

However, I found out the hard way yesterday that a G125 broke the plastic fin can at mach transonic range.

Interesting shred on an old time motor I must say.

I flew an ellis I-134 in a 38mm rocket with an Acme fin can. nothing special to 6742.

I hope to rebuild a 32mm Bird with a 29mm mount. this time with light weight fiberglass fins that look like those on a Loc Nuke.

Much better at transonic speeds. Hope it goes two miles on my I-69 as well.

Let me know what you end up doing with yours.

Art Upton

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Reply to
ArtU

Yes I did,

It was a very small, very light rocket with a transmitter and bird tape streamer.

Ron Zeppin donated the motor, and Andy Woerner loaned me the transmitter and ATV.

I think the igniter hung up for a sec because the rocket did a very serious wiggly-woop at about 15 feet then headed north at about a 45 deg elev trajectory. I found it about 3 miles away. I was able to watch the deployment and descent through binoculars thanks to the bird tape. I think it hit about 2 mile altitude but not sure. Jim's experimental altimeter in the nose got shook silly and we couldn't retrieve data.

It's a great little inexpensive rocket design for this kind of thing- I could send you the rocksim file.

-Bruce OBrien

Reply to
Bruce OBrien

Propulsion Polymers I80/Altacc 2B in an extended LOC Weasel. Did 7845ft, recovered using the last-minute Walston about two hours later. Set the CAR 'I' altitude record, which was then bested by Vince Chichak a couple of months later, with an altitude that was slightly higher than mine +/- error margins on the Altacc altimeter. I think Vince was using a CTI 'I', but I don't remember which one.

Reply to
Marcus Leech

Is the PP I80 a full "I"?

Both you and Bruce are making me wonder more about the field, something we may not have much of along the Gulf Coast...

With 370 NS, I doubt the I69 would break any record... Still ought to be interesting.

Best, Andy

Reply to
Andy Eng

Ahhh.... The G125... Fun little motor! :-)

With AT catching up, the Ellis Mountain SUs seems to be filling a fun niche of motors - The Econojets of HPR?

Right now, I'm in the imagineering phase of the project.

Andy

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Reply to
Andy Eng

I've always used either metallic mylar for visibility on G motor mach busters and something like six of six in getting these back but not sure it'll hold up here. Dunno. I've some mica film that doesn't tear but not as visible as the metallic mylar. What's bird tape?

Andy Woerner is a class act. We were visiting a launch at the Hemit dry lake and sunk the rental car through the mud crust - buried both axles. Andy got us out. Rental car never quite drove right for the rest of the trip...

Hmmm... Will plan on a 30awg custom dip ignitor. Hard to light?

Wondering if there was some propellant shluffing (sp?) going on with the higher l/d...

I'd be interested, especially to see if there was possibly some dynamic instability.

Best, Andy

Reply to
Andy Eng

I've been messing around with 'I' motors in RS (for no particular reason) and I found that the motor that turned up the best altitude was the RATTWorks I90 (the biiig one), since its 29mm and a reasonable I (over 500 Ns IIRC). This turned up over 10,500 feet. The current UKRA I record is about 8700 ft, so there is room for some improvement. A 29mm slow I sounds like a good motor for going a long way up, how about set up the minimum amount of rocket (in RockSim) and running the optimal mass calcs?

-- Niall Oswald ========= UKRA 1345 L0 EARS 1151 MARS

"Gravity assisted pieces of the rocket raining from the sky should be avoided. It is also financially undesirable."

-Portland State Aerospace Society

Reply to
Niall Oswald

Andy

I have sold quite a few I69 and they fly well. I have not seen a min dia yet..... H 50's are great motors for L1 cert w/o the hw expense.......

H275 in a min dia is a maniac flight 1 sec burn time movin up QUICK.........

Tried one of them in an Aerotech SUMO.... hung together but she was MOVIN........

All of the Ellis SU are great motors... G35-10 can put an aerotech mustang close to a mile.......

Bobby B

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Reply to
bobbyb

Andy, I have flown the H268 to 9275 in a 29mm min dia rocket. The trick is making them strong enough for the flight but not to heavy. As far as getting them back..mylar works if you have the room or white "tracking chalk" works good too..watch where other people recover rockets from..if your rockets flies as straight as thiers did..you should find yours in the same general direction..but farther out..then they did..I have a Ratt works I90 I want to fly in this rocket.. I have been looking at the Ellis SU longish burn motors just have not had the time yet to try one.

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Reply to
Tony Alcocer

Hello Tony,

Gorgeous yellow fin-can you got there! :-)

Andy

Reply to
Andy

Nice website!

What type of "establishment" were you dumpster-diving when you found the fiberglass airframes?

Thanks, Patrick

Reply to
Patrick Harvey

No. About 460NS.

Indeed...

Yes, I'd say it would be very interesting to watch. My flight was still burning when it disappeared from sight. I'm awfully glad about the Walston I put in it...

Reply to
Marcus Leech

The "fiber glass pipe" is used at gas stations..They have been doing lots of new tank instalations around here..I get the short pieces..4' or less...I guess they can't use them. I've gotten it in 2.375, 3.5,

4.5" You do have to figure out something for nose cones becasue of the odd ball sizes. Tony
Reply to
Tony Alcocer

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