MADCOW SUPER DX3 CARDBOARD

[josong]

Hello!

I'm about to attempt an L2 cert with my 4" cardboard kit, the Madcow SuperDX3 on an aerotech j420. It is 3.3kg (7.3lbs). Using average thrust it gave a TWR of 13:1. Just wanted to get everyone's opinion out if this motor is too high for me or if I should scale it down just a bit. It is a cardboard rocket and I hope the airframe can keep it together during flight.

Has anyone else had experiences like this?

Thanks!

 

[tsmith1315]

That’ll be fine. What’s your expected altitude, 4k’ or so?

 

[josong]

That’ll be fine. What’s your expected altitude, 4k’ or so?

Just shy under 3k. 2990ish to be closer

 

[tsmith1315]

Just shy under 3k. 2990ish to be closer

It should be a great flight! Are you using motor deployment, or electronic?

 

[josong]

It should be a great flight! Are you using motor deployment, or electronic?

Dual deployment! RRC3 main, RRC2+ backup and RF tracker.

 

[Titan II]

You are fine.

 

[tsmith1315]

Dual deployment! RRC3 main, RRC2+ backup and RF tracker.

Sounds like you’ve got it all covered. Good luck, and post some pics!

 

[GalantVR41062]

I built my 4" super DX3 cardboard kit like a tank.

Redundant dual deploy and used a Loki J320R for my L2 attempt and cert.

It has flown on a punchy H motor a few times and a CTI J53O IMAX motor to 5,600' and 850'/s.

Hard to say what yours will handle with out knowing: how it was build, flight profile, drag, previous flights.

 

[Theory]

SEND IT!!!!!!!!!!!!!!!!!!!!

 

[MikeT]

You'll be fine. I've beaten mine to death and it still fly's great. I fly it almost every launch.

 

[sriegel]

Used that kit for my L2 to 3300'. I glassed the top of each tube as zipper mitigation and glassed the fin can because why not. But I suspect you will be just fine stock. It's a solid bird.

 

[loopy]

Totally fine. The only concern you'd need to have with it (assuming it's built with good fillets for the fins and what not) is if you're getting close to mach, but I wouldn't imagine that's a concern with that combo. I did my L2 on a LOC Expediter (cardboard tubes, plywood fins) on a J500, and it was fine. Same rocket has gone over a mile up on a J570. Send it!

 

[josong]

Hey all! I got my L2 cert with no problems at all! I opted for shear pins instead of a friction fit nosecone. All things considered the flight was a phenomenal textbook dual deploy flight. Thank you everyone who reassured that I'd be okay as I bit the bullet and flew that bad boy to almost 3000 feet at Mach 0.5

 

[sriegel]

Congrats on the cert!

 

[bad_idea]

Congratulations!

 

[cwbullet]

Congrats.

 

[WizardOfBoz]

Congratulations! I hope to be trying that same kit for my L2 soon. I think I'm gonna use a J270W. OR predicts 3200' apogee. I've build Cris Erving's Eggtimer altmeter and the flight computer for the EZ-DD, so I suspect I'll use the Eggtimer Quantum or Proton for Dual Deploy.
I have a 42" spherachute which works great but for some reason I am fixated on finding a ringsail chute. I'd like to use about a 48" ringsail for DD. For giggles. I think that theres an issue with delivery times (among other things) with Rocketman. So I suppose I'll just use the spherachute.

BTW, I used a LOT of glue and added an extra bulkhead (just in front of the fin tangs, to take the thrust from the rear CR) but my rocket is only about 5 lbs. how did you get the weight to 7 lbs?

Anyway, I have to secure a motor. I have a lead that I can pickup at the MDRA launch.

 

[kjhambrick]

Hey all! I got my L2 cert with no problems at all! I opted for shear pins instead of a friction fit nosecone. All things considered the flight was a phenomenal textbook dual deploy flight. Thank you everyone who reassured that I'd be okay as I bit the bullet and flew that bad boy to almost 3000 feet at Mach 0.5

Beautiful Red flame and a nice straight flight on that AT J420R, @josong !

Thanks for the video and Congrats !

-- kjh

 

[loopy]

MAN, I love the flames on the redlines! Great job! Congratulations!