I killed my Kraken!!!!!

Advertise with us
madcow rocketry
SilicdyneTRF
eggtimer rocketry
The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
AHansom

AHansom

Well-Known Member
Joined
Jan 22, 2009
Messages
915
Reaction score
178
Location
Santa Barbara, CA.
A 6" Kraken built completely out of BlueTube on a CTI M2020 sounded good at the time but I guess I pushed it a little to hard. Towards the end of the burn it just exploded the fins off. Cant believe how it just tore the tube fins to shreds. Guess its time to rebuild:wink:

photo-4.JPG

Ekraken1.jpg
 
Last edited:
The thrust was too much for the drag created by the fins.
 
6" with an M2020...must have had an altimeter; can you post the file? I'm considering making a kraken for fun in the near future (some scrap 1.75" CF tubing I want to use some of, good for 38mm motors). I'm interested in how much stress it was under when it let go. Sorry to see such a beautiful rocket go though!
 
So sorry to hear the Kraken went meet the rocket gods. What speed was it doing at the time?
 
I guess I should have been more compassionate about your loss.

I build on similar but not 6 inch (54 minumim) and not on an M. It developed what I will call tube flutter and the ends result was the same.
 
I think Larry Brand sets his speed limiter screw to about 650 (it's right next to the atitude adjustment). OTOH- that's one of the best 'under boost' pictures I've seen. Sorry for your loss. Long live the King!
 
CCotner said:
6" with an M2020...must have had an altimeter; can you post the file? I'm considering making a kraken for fun in the near future (some scrap 1.75" CF tubing I want to use some of, good for 38mm motors). I'm interested in how much stress it was under when it let go. Sorry to see such a beautiful rocket go though!
Click to expand...

Thanks for the sympathy, The Kraken died swiftly!! Not sure how much stress it had except it was just a little to much. I still have a hard time believing how shredded the tube fins were. Most of the pieces we found were in the 4"x4" size. BlueTube is so tough I know I would have a hard time ripping it into pieces like that

View attachment os.FIPa
 
Last edited:
Oh man, sorry to see that! Did it lose stability when the fins came off?
 
It was a great flight up to the shred. I took a lot of video's this weekend, but I think I was prepping when they announced your flight so I had just enough time to get up and watch. Thanks for stopping by and saying hi. I had a lot of fun and my kids are looking forward to the next launch.
 
qquake2k said:
Oh man, sorry to see that! Did it lose stability when the fins came off?
Click to expand...

Yeah it lost stability severly tumbled around and the rest of the rocket came apart as the motor finished burning. I was surprised when I opened up the ebay to see the Ravens capacitors had been stood straight up from the lateral g-force.

os2.jpg
 
AHansom said:
Thanks for the sympathy, The Kraken died swiftly!! Not sure how much stress it had except it was just a little to much. I still have a hard time believing how shredded the tube fins were. Most of the pieces we found were in the 4"x4" size. BlueTube is so tough I know I would have a hard time ripping it into pieces like that
Click to expand...

(Holds hat over heart) Sorry about your loss, sir :sad:

I see something interesting in the flight data. To my eye it suggests you actually got to the end of the motor burn OK at about 3.1 seconds. And then it briefly entered coasting flight, and it looks like it started to come apart at about 3.35 seconds. (somebody double check my observations here OK?)

And it was HOT - a hundred and eleven degrees - for the entire flight. Black rocket in direct sunlight, maybe?

Anyway I hope you got some usable parts back.
 
cvanc said:
(Holds hat over heart) Sorry about your loss, sir :sad:


I see something interesting in the flight data. To my eye it suggests you actually got to the end of the motor burn OK at about 3.1 seconds. And then it briefly entered coasting flight, and it looks like it started to come apart at about 3.35 seconds. (somebody double check my observations here OK?)

And it was HOT - a hundred and eleven degrees - for the entire flight. Black rocket in direct sunlight, maybe?

Anyway I hope you got some usable parts back.
Click to expand...



Interesting, I havnt checked that yet but the motor was probably ramping down quickly. I think its listed as a 4.5 sec burn time.

Wasnt Black Rock and some might say its worse!! Fresno in the Fall:y: Actualy it was a great day only mid to high 70's
 
Last edited:
A moment of silence please, for Kraken, it was a good rocket.

One of the most impressive shred/stability photos I have seen. Sorry for your loss.
 
AHansom said:
Wasnt Black Rock and some might say its worse!! Fresno in the Fall:y: Actualy it was a great day only mid to high 70's
Click to expand...

Not Black Rock, black Rocket! Check the temperature data in your file. Baby was pretty hot. I wonder if the glue got soft?
 
AHansom said:
Yeah it lost stability severly tumbled around and the rest of the rocket came apart as the motor finished burning. I was surprised when I opened up the ebay to see the Ravens capacitors had been stood straight up from the lateral g-force.
Click to expand...

Epoxy the capacitors down; it will protect them from extreme G-forces.
 
CarVac said:
Epoxy the capacitors down; it will protect them from extreme G-forces.
Click to expand...

But there wernt suposed to be any extreme G-forces. :confused2:

Good idea!! None of the ejection charges fired so I got to give them a good once over this weekend and make sure there still allright. If they check out Ill epoxy them down
 
I remember seeing it happen--a beautiful boost, and then it looks like one of the tube fins tears off, and the rest comes apart. My impression is that the shred is towards the end of the burn. As the first fin tears off, the rocket starts spinning about itself spewing exhaust in all directions. My guess at the time is that the fin tears off as it hits Mach towards the end of the burn. Wonder if altimeter data supports this theory.

Beautiful rocket.

Sad to see it go.

Ari.
 
AHansom said:
Yeah it lost stability severly tumbled around and the rest of the rocket came apart as the motor finished burning. I was surprised when I opened up the ebay to see the Ravens capacitors had been stood straight up from the lateral g-force.
Click to expand...

That was a crazy ride!
 
iter said:
I remember seeing it happen--a beautiful boost, and then it looks like one of the tube fins tears off, and the rest comes apart. My impression is that the shred is towards the end of the burn. As the first fin tears off, the rocket starts spinning about itself spewing exhaust in all directions. My guess at the time is that the fin tears off as it hits Mach towards the end of the burn. Wonder if altimeter data supports this theory.

Beautiful rocket.

Sad to see it go.

Ari.
Click to expand...

Looking at some of the photos there's a disturbed smoke trail with confetti all around just before the rocket went unstable. Cant check the altimeters for a few more days so im not sure if it hit mach or not but it was close.

Are you connected to the TCC chat? There have been some cool photos of your glider posted.

oskrakenfin.jpg
 
I'm not on the TCC list, but I have photos from Martin Hall (including wonderful pictures of my daughter doing a post-landing safety check). If there are others, please point me to where I can get them!

Ari.
 
Last edited:
Oh the horror and humanity!! Was a beautiful rocket, obviously alot of work and expense. My sincere condolences.

(But the pictures are way cool, wish I could have been there to witness it!)

Terry
 
Finished cleaning out motor casings and the range boxes. Now its time to step back and see what can be done. Don't think I found all the pieces and I'm not that good at puzzles so I'm going to order a couple of new tubes and cut new fins. The main body tube looks OK and I think I can grind away the epoxy fillets and BlueTube remnants and get it back to where I can attach new tubes.

photo-6.jpg
 
I was not aware blue tube came in so many shapes and sizes!!
 

Similar threads

GAP
Leave No Doubt: An M2020 to Mach 3 (ish)
Replies
8
Views
1K
kjhambrick
K
mago0
5.5 Goblin build for my L1
2
Replies
32
Views
2K
mago0
mago0
bandman444
NSL 2024: A 24" Diameter 1/6th SpaceX Dragon Pad Abort Test
2
Replies
31
Views
1K
Daddyisabar
Daddyisabar
boatgeek
Fafnir, a 3" Dragon-Themed Rocket
Replies
3
Views
142
boatgeek
boatgeek
Glasspack
Bad Luck or bad motor at LDRS41
Replies
16
Views
1K
Glasspack
Glasspack

Latest posts

Back
Top