Madcow Avlanche

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That was all the paint I had & I'm no fan of UF. Really didn't want to paint it at all but a white rocket doesn't show up too well with clouds in the background!
I was able to fit a 50" TFR in the NC. It's snug but pulls out with no resistance at all.

Are you or anyone else using a drogue, and if so what size?
 
I’m using a 12 inch drogue.
My experience in the past with HED deploy Rockets tend to come in pretty fast without a drogue.
 
Thanks Tim. My Avalanche is 82.6oz. I am planning on a 9" drogue and a 50" main with a Chute Release. How would you configure? Main on NC and drogue on harness or reverse?
 
Since I was able to fit the 50” TFR in NC, went with that configuration. Also using 15’ of 1/4” Kevlar in NC.
Is that 82 Oz inclusive of recovery & electronics? I also used 1/4” quick links which I guess I can remove. Only downside of quick links is loss of altitude.
 
Tim I wasn't clear. First the 82oz includes the electronics and laundry, however not what you may expect. No front end deploy. My NC will contain a Jolly Logic Alt3 and a BRB900 on an Atterbery AV sled. I shortened the NC coupler to 3" and will have both main and drogue in the BT, as I said the main will have a Jolly Logic Chute Release. Since I plan on only flying 38mm motors I did no internal filets, so between that and losing all the intended AV hardware that should account for the weight discrepancy.

So back to my original question. Using a 3 loop harness would you have the drogue on the NC loop with the main + CR on the loop that is short of the NC or vice versa?
 
So back to my original question. Using a 3 loop harness would you have the drogue on the NC loop with the main + CR on the loop that is short of the NC or vice versa?

Have only tried that setup once with JLCR on 2stage booster & unfortunately the main got all fouled so I gave up that idea. On subsequent flight I tossed the drogue & reefed the main with JLCR and that worked out well. Maybe someone with the setup you desire will chime in.
 
My Avalanche is nearly done. Just finishing up the paint. Deployment tests went very well with the Eggfinder . I used 1.5g black powder for the drogue and 25' of 1000 lb kevlar cord was almost fully extended. 1.0g of black powder for the main almost fully extended 15' of shock cord. The drogue is a Dino Chutes Guide 24" but it's a sharp cone shape which descends fast. The main is a Top flite thin mill 58" which easily fit in the nose cone wrapped in 12x12 fireproof cloth.

Final weight is 2624g or 92.55oz or 5lb 12.5oz.
It's heavier than I expected since the raw kit components weighed 4.5lbs. I added an Aeropack tailcone and lots of epoxy through the fin slot with epoxy cartridge mixing tips. I don't think there's a better way to stick fins and make fillets, and this happens at the same time easily. There's no mixing or mess.

Heading to LDRS on Saturday morning.

Motors and altitude predictions:
First flight: I357W to 1789'
Drag race: I599N to 2267'
L2 cert: J350W to 4875'

Original paint design by me, generated in Inkscape, wrapped in RockSim, and pieced together in Paint.net.
Toby%27s%20Madcow%20Avalanche.jpg
 
Yours looks really similar to mine.... Love the paint design... I will fly mine when you do your test flight. 0516181321.jpeg0516181321a.jpeg0516181446.jpeg
 
Deployment tests went very well with the Eggfinder . I used 1.5g black powder for the drogue and 25' of 1000 lb kevlar cord was almost fully extended.

Keep an eye on the apogee deployment.

Since you are using a drogue, you only need to get the drogue into the air stream and the drag of the drogue will pull the 25' of cord tight. In other words, just get the rocket open. Parts tend to move faster and farther in the air than on the ground tests. After observing your flights, you might want to consider dropping the apogee charge to 1.25 or even 1.0 if it looks like the payload is hitting the end of the cord hard. The shock at the end of the cord is what makes the nose cone come off and give you a main deploy at altitude and why some folks go straight to the more complicated shear pins and larger main deploy charge when a friction fit would work without the large apogee and main charges.

Good Luck....
 
I agree with Handeman. I’m using 1.0 gram for apogee charge. Have several 3” rockets with HED deployment & they all successfully deploy drogue with only 1.0 grams BP.
 
I agree with Handeman. I’m using 1.0 gram for apogee charge. Have several 3” rockets with HED deployment & they all successfully deploy drogue with only 1.0 grams BP.
I had a bad motor or case in the drag race. I599 rocket went up about 10 feet but before it was even off the pad, the everything except the aft closure was ejected out the top. Rocket sustained minor scrapes. I'm going to try the J350 for L2 cert in the morning. Aerotech replaced my motor and case.

I can go down to 1g on the drogue. I have 1g in the nose. Should I reduce that too?
 
I had a bad motor or case in the drag race. I599 rocket went up about 10 feet but before it was even off the pad, the everything except the aft closure was ejected out the top. Rocket sustained minor scrapes. I'm going to try the J350 for L2 cert in the morning. Aerotech replaced my motor and case.

I can go down to 1g on the drogue. I have 1g in the nose. Should I reduce that too?

I'm using 1.0 gram in both main & drogue. Are you using shear pins?
 
It was great meeting my fellow Avalanche drag racers in Heat 1 yesterday. Hard to believe I got farthest from the pad on an I218 ! Good thing GPS works in wheat fields.
IMG_0552 (2).jpg
 
Easy win for me, with one CATO on the pad and Will's shred on the K300. Although Will's rocket had caught me in the picture, my I218 lit first and got me off the pad first, and since he shredded, I got highest altitude. Then my skinny little streamer drogue and 300 ft. main deployment got me back down first, unless you count Todd's cato (which was awesome, but disqualified him). I landed about 100 yards from the pads, so I think that was a clean sweep. James gave everyone 5 points for the beauty contest, and I had a small holographic decal from Stickershock.


  • LDRS37 Decal – 5 pts
  • Most beautiful rocket – 5 pts
  • First off the pad – 30 pts
  • First on the ground – 20 pts
  • Highest Altitude – 20 pts
  • Shortest recovery distance – 20 pts
The prize for the win was another Avalanche kit, which was promptly confiscated by my loving wife....
 
Easy win for me, with one CATO on the pad and Will's shred on the K300. Although Will's rocket had caught me in the picture, my I218 lit first and got me off the pad first, and since he shredded, I got highest altitude. Then my skinny little streamer drogue and 300 ft. main deployment got me back down first, unless you count Todd's cato (which was awesome, but disqualified him). I landed about 100 yards from the pads, so I think that was a clean sweep. James gave everyone 5 points for the beauty contest, and I had a small holographic decal from Stickershock.


  • LDRS37 Decal – 5 pts
  • Most beautiful rocket – 5 pts
  • First off the pad – 30 pts
  • First on the ground – 20 pts
  • Highest Altitude – 20 pts
  • Shortest recovery distance – 20 pts
The prize for the win was another Avalanche kit, which was promptly confiscated by my loving wife....
Nice. What was your altitude ?
 
Thanks. I reached 2669ft. Small consolation for walking around in the wheat field for 15 mins. Guess I should have set the main chute waaay lower. I just used the default 700 ft in my altimeter. Clearly a rookie mistake !
 
Thanks. I reached 2669ft. Small consolation for walking around in the wheat field for 15 mins. Guess I should have set the main chute waaay lower. I just used the default 700 ft in my altimeter. Clearly a rookie mistake !

Great flight!
I retract my "clean sweep" comment. Must have been that slick paint job! Glad you found your rocket.
 
I had a CATO with an I599 in the drag race. Only the aft retainer remained in place. The rest of the case and motor shot out the top.

Here is James preparing for our launch. Mine is the blue one on the right.
DSC02520.JPG


Liftoff! Pretty sure I'm going to get first to the ground.
DSC02533.JPG


And closest to the pad. Actually under it with my av bay.
DSC02545.JPG


I reassembled and launched it on Sunday morning for my L2 cert on a J350W. But the electronics never fired the deployment charges. All 48" in the ground.
2018-05-20%2009.48.49.jpg


Serious excavation.
2018-05-20%2013.00.43.jpg


And total destruction.
2018-05-20%2014.14.30.jpg
 
Eggtimer TRS.
Everything seemed perfect. Battery (800mah) was freshly charged. I turned on the electronics with a PCB screw switch. Got a connection to the LCD. Checked status and all was OK. Started a flight and finally got a GPS lock just before launch. There was no indication of a problem. Cris is going to analyze the TRS to see if he can pull any data.
 
Really dumb question but did you arm it ? I’ve heard a few stories where people turned on GPS but never armed TRS at the pad.
 
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