New I motor record - 15,157'

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GrouchoDuke

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The winds were howling at Delamar yesterday, but I managed to eek out a flight that should set a new I-motor record with my Vanish 38. The rocket took a pretty good turn off the pad from the wind, then flew straight to apogee. Tripoli Vegas' yearly Delamar launch has been really good to me. The rains over the last week threatened to cancel the launch, but the water on the lakebed cleared just enough to allow launches for the event. The launch is great fun and it's always awesome to hang out with everyone.

My rocket started life as a Go Devil 38 kit, but I hacked & slashed down to min-size and it a dose of new carbon fins. Dry weight was about 12 oz. I had a TeleMetrum on board and flew a CTI I216. I lost telemetry when it went behind a mountain while still about a mile in the air. It landed about a mile downrange from that last known point and landed in some muddy bumps that killed its telemetry range. I picked it up with a ham radio at about 500 feet away and DF'd to about 150' away where I finally got another telemetry hit. It took almost 3 hours to find it.

Huge thanks to Rob702Martinez for his awesome help with the recovery and to Pat Harden for his support as a TAP.

There's definitely room for a higher flight -- I'll be back for more!

Here's a video:


IMG_0890.JPG IMG_0948-crop.jpg IMG_0903.JPG Vanish 38 flight graph - 20190525.png Vanish 38 flight stats - 20190525.png
 
Schweet!

Congrats on the record. Good luck on making it all official.
Gotta love Tripoli Vegas....some of the best flyin' folk and launch fields there are.
Can't quite see from your pics.....what did you do for motor retention, and what's up with the aft closure of that motor?

s6
 
Nice job!

The non-Tripoli sanctioned I record is over 17k, btw, by Adrian A here on the forum.
 
Thanks everybody!
That chute didn't really slow you down all that much it seems. Did you fly it drogueless with a JLCR?
Nope, I brought it down fast with a little chute. There wasn't room for a JLCR - it's just single deploy. The 50k waiver at Delamar has a big radius, so I wasn't concerned (too much) about where it landed.

Gotta love Tripoli Vegas....some of the best flyin' folk and launch fields there are.
Can't quite see from your pics.....what did you do for motor retention, and what's up with the aft closure of that motor?
Tripoli Vegas is an outstanding group. We're planning to move away from here later this year and we'll miss them a ton. There better be a great group wherever we end up!

The closure. Ugg. That's what ships with the I216, so that's what I have to use. I asked CTI about the tapered closure that Adrian mentioned a while back and they don't have anything like that now. I would love the drag reduction of a tapered closure like Adrian flew with. If anyone has an I216 with one on it, please let me know!

Motor retention is just friction fit.

The non-Tripoli sanctioned I record is over 17k, btw, by Adrian A here on the forum.
Yeah, I'm definitely familiar with the flights he's talked about here and the ones talked about over at RasAero. He's really knocked them out of the park. There's also a university group that posted about hitting somewhere near 16k on this motor. Like I said, there's room for improvement -- still, as the rules stand, this flight should be a new official record. I really love record hunting. Min-diameter rockets are crazy fun. I think more people should do it!
 
Nice flight. Interested to hear more details about construction / design.

Need to get my act together and refine the purple parrot for another flight.
 
Congrats on the flight and record.

The closure. Ugg. That's what ships with the I216, so that's what I have to use. I asked CTI about the tapered closure that Adrian mentioned a while back and they don't have anything like that now. I would love the drag reduction of a tapered closure like Adrian flew with. If anyone has an I216 with one on it, please let me know!
You might be able to 3D print a tailcone, or machine it in balsa, then glue it in place. Not as clever as something that threads on, but potentially a way to get a little less base drag.
 
I flew an AeroTech Mustang kit modified for 38mm mount at Lucerne dry lake with an AeroTech I132 to 17,500' sometime around 1992. Did not find it afterwards..... This is the Only known photo.
Scott%27s Mustang GT.jpg
 
I'm curious, did you have a ham radio beacon in addition to a GPS tracker? I've thought that the RF beacon close to a GPS would inhibit its ability to get a good lock. Or did you do direction finding on the GPS transmitter?
 
Thanks everybody! Nope, I brought it down fast with a little chute. There wasn't room for a JLCR - it's just single deploy. The 50k waiver at Delamar has a big radius, so I wasn't concerned (too much) about where it landed.

Tripoli Vegas is an outstanding group. We're planning to move away from here later this year and we'll miss them a ton. There better be a great group wherever we end up!

The closure. Ugg. That's what ships with the I216, so that's what I have to use. I asked CTI about the tapered closure that Adrian mentioned a while back and they don't have anything like that now. I would love the drag reduction of a tapered closure like Adrian flew with. If anyone has an I216 with one on it, please let me know!

Motor retention is just friction fit.

Yeah, I'm definitely familiar with the flights he's talked about here and the ones talked about over at RasAero. He's really knocked them out of the park. There's also a university group that posted about hitting somewhere near 16k on this motor. Like I said, there's room for improvement -- still, as the rules stand, this flight should be a new official record. I really love record hunting. Min-diameter rockets are crazy fun. I think more people should do it!

The fact that Rf tracking is so affordable makes that last statement so true now. Although the Ham bands offer a bit more performance edge over the 100mW ISM stuff, I can find all my outta sight sport rockets absolutely fine with my EggFinders. If I was really going "way long", I'd use my 100mW Beeline GPS on the 70cm band.
If one has the room, the AP510 works on the 2 meter band and with 1watt output would really perform.
A fellow posted here a few years ago he really likes his on the playa. Kurt
 
What a cool flight..Good for you man..
A big congrats are in order for sure..

Teddy
 
You might be able to 3D print a tailcone, or machine it in balsa, then glue it in place. Not as clever as something that threads on, but potentially a way to get a little less base drag.
Yeah, I've thought about that. For this flight, I didn't attach anything to the outside of the stock closure. It's almost the same diameter as the body tube, so I can't do too much tapering. Just cleaning up the little finger hold notches in the closure would really help too.

I flew an AeroTech Mustang kit modified for 38mm mount at Lucerne dry lake with an AeroTech I132 to 17,500' sometime around 1992. Did not find it afterwards..... This is the Only known photo.
View attachment 384240
That's amazing for non-min-diameter rocket on only 610Ns of motor. I'd love to see whatever telemetry data you have on that flight.

I'm curious, did you have a ham radio beacon in addition to a GPS tracker? I've thought that the RF beacon close to a GPS would inhibit its ability to get a good lock. Or did you do direction finding on the GPS transmitter?
I just used the TeleMetrum's standard output beep to direction find on. I didn't bring a Yagi, so I just used my body to shield my HT to find the null and went that way. We couldn't hear it at all until we got really close, even when standing on top of the truck & holding the HT about 10' in the air. After driving around for a few hours with no luck I used the last few telemetry points to calculate an estimated landing spot, then went there and started my search. We found it pretty quickly after that.

If one has the room, the AP510 works on the 2 meter band and with 1watt output would really perform. A fellow posted here a few years ago he really likes his on the playa.
Room is always extremely tight on these kinds of rockets. I didn't have room for an additional tracker on this rocket. There are some great really small RF beacons out there though.

What a cool flight..Good for you man..
A big congrats are in order for sure..
Thanks Teddy! I really appreciate it.
 
What a blast! I learned so much from Brian this weekend. Just observing and being apart of the record flight. So much planning and preparation go into a flight like this. From pre flight check lists, construction, problem solving to tracking the rocket down. Absolutely brilliant. With all the activities this weekend and all the other successes from all the other flights, this one tops the list. Congratulations Brian, well done and well deserved record!

Oh and ditches are deeper and wider than they appear LOL:eek::confused:o_O:D
 
Congrats on the record
I was trying to set it way back when cardboard airframe tube was all we had and AT I132 were the motor to use. We thought we were doing great at anything over 10,000’. Visual tracking of course (Thank you Chuck)

M
 
Way to go!!!!!!!!!!
An apogee bustin' 38mm I motor rocket is on my bucket list too.
(Why CTI Pro38's rear closure is part of the nozzle, unlike the other diameters where CTI offers tapered closures...what's up with that, CTI?)
Anyway, CONGRATS!!!! That is really awesome. :)
 
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What a blast! I learned so much from Brian this weekend. Just observing and being apart of the record flight . . . Oh and ditches are deeper and wider than they appear LOL:eek::confused:o_O:D
Hahaha - "DIIIIITTTTCHHHH!" <Kaaabaaam!> Thankfully the 4x4 was able to do some good work out there. Thanks Rob, you're too kind.

Congrats on the record
I was trying to set it way back when cardboard airframe tube was all we had and AT I132 were the motor to use. We thought we were doing great at anything over 10,000’. Visual tracking of course (Thank you Chuck)
Thanks, I appreciate it. It's incredibly impressive to visually track something that small to 10k - nice! Sounds to me like you should get back into record hunting! ;)

Way to go!!!!!!!!!!
An apogee bustin' 38mm I motor rocket is on my bucket list too.
(Why CTI Pro38's rear closure is part of the nozzle, unlike the other diameters where CTI offers tapered closures...what's up with that, CTI?)
Anyway, CONGRATS!!!! That is really awesome. :)
Thanks a bunch, srfrich. I tell ya, I'm about ready to pay for the development & testing of a tapered closure for the I216. :) Like I said before, MD rockets are really fun. The speed that the Go Devil 38 goes out of stock at Madcow seems to hint that lots of people like this size. Even a stock GD38 can go really high on not much motor. For the size of electronics these days, 38 seems like a great size in the bang-for-your-buck category. If you're up for working in the tight space of 29mm rockets, the CTI 29mm I motors are great for pushing them really high too.


On further review of the data with the recorded data with the records committee, it looks like the official altitude might be 15,159 feet. So far, so good. Fingers crossed for the "official" stamp soon!
 
Great, thanks. As I understand it from emailing with the records committee a while back, modifying the closure would disqualify it from any record attempt. Sure would be nice though. I might try that on a non-record flight.
I'm not entirely sure about that. Granted I'm not a TRA member anymore but my expectation is that photo is of Charlie Ogino's I motor record flight from 2015. CJ calls it out as a record holder in the thread he posted it in and the flight is listed on line 42 on the Tripoli Records single stage page.
 
I'm not entirely sure about that. Granted I'm not a TRA member anymore but my expectation is that photo is of Charlie Ogino's I motor record flight from 2015. CJ calls it out as a record holder in the thread he posted it in and the flight is listed on line 42 on the Tripoli Records single stage page.

I think I recall Jim posting a copy of a communication with CTI where Zcti approved the modification of turning the Pro38 closure on a lathe to form a tailcone. I don’t know whether the records committee chair would accept that, but I’m sure that without it the modification would not be approved.
 
I think I recall Jim posting a copy of a communication with CTI where Zcti approved the modification of turning the Pro38 closure on a lathe to form a tailcone. I don’t know whether the records committee chair would accept that, but I’m sure that without it the modification would not be approved.
https://www.rocketryforum.com/threads/odin-minimum-diameter-38.66514/#post-717622

https://www.rocketryforum.com/threads/wildman-blackhawk-29-build.29085/#post-261885

Jeroen 38mm tapered site:www.rocketryforum.com

Tony
 
The link above indicates 54mm but photos seem to show a 29mm....
The thread was started in reference to CTI 54mm tailcones but the link I provided has a photo of a 38mm CTI rear closure that's been turned down in a lathe and then a photo of 3 photos of Jeroen's BlackHawk 29 with the factory made 29mm CTI tapered closure.
 
I'm not entirely sure about that. Granted I'm not a TRA member anymore but my expectation is that photo is of Charlie Ogino's I motor record flight from 2015. CJ calls it out as a record holder in the thread he posted it in and the flight is listed on line 42 on the Tripoli Records single stage page.
That's good to know. The photo of that rocket does look like it has a tapered closure on it. There's another post where Jeroen talks about having tapered rear closures available. I asked CTI about this about a year ago and was told that they never had anything like this. It's possible that the person I talked to just didn't know.

I think I recall Jim posting a copy of a communication with CTI where Zcti approved the modification of turning the Pro38 closure on a lathe to form a tailcone. I don’t know whether the records committee chair would accept that, but I’m sure that without it the modification would not be approved.
Thanks Steve. I wrote the records committee for clarification. If they say it's ok, I'll write CTI again to see if they can dig up what they've done in the past.

Congratulations on a fantastic Flight !
Thanks Kenny!
 
Congratulations, and well done on recovering such a small rocket so far from the pad, that’s no small challenge on its own!
 
Congratulations, and well done on recovering such a small rocket so far from the pad, that’s no small challenge on its own!
Thanks y’all. Yeah, finding the rocket after losing telemetry was definitely a challenge. I bet we off-roaded through the desert at least 15 miles while looking for it. We drove within about 1000 feet of it I think 3 times before I gave up hunting and pecking for. The real trick to finding it since we didn’t have any radio reception, was looking at the last few telemetry data packets and calculating an approximate landing location from that.

I’m planning to do a G-motor record attempt this weekend in a Hartsel, CO. I won’t have a GPS on that rocket, so it’ll be all DFing. I finally caved and bought an Arrow Yagi. That helped a ton in finding my G rocket when I flew it a couple weeks ago here in Vegas. My tape measure Yagi just didn’t cut it last year when I was hunting for it at Hartsel. Thankfully body shielding my HT worked well enough to find that rocket. I really hope the weather cooperates this weekend. If not, at least trips to hang out with Tripoli Colorado are always fun.
 
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