I blew up my THOR

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Well-Known Member
TRF Supporter
May 1, 2002
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Central Iowa
Well I attempted my Level 2 cert flight today (3-20-04) with my BSD THOR on an AT J350.

Motor lit off and the thrust ring on the motor adapter let go, the J350 went up through the rocket and it wasn't a pretty site.

Rocket is totaled except for the nosecone. Will try to get some pictures and video up on the website tomorrow.

I guess I'll try again at Whitakers next month........
I'm very sorry to hear that...but don't get too discouraged! If it was easy, they might as well have given you the L2 cert.

The J350 is one butt kicking motor. It will tear a rocket apart if given the chance...same thing happened with my dad's L2 Bull Pup on one...except that CATO'd.

Don't give up! That beautiful AMRAAM will take the J350 nicely, and it uses PML's tested Adapter system. Keep on goin man, you'll get it:)
The same thing happened to my Magnum... with an AMW 38mm J500. That motor peaks at about 180 lbs of thrust 1/3rd of a second into its burn. That is when the thrust ring on my adapter decided to go... now that is a real butt kicking motor!
I'm sorry to hear that, but as Dan said don't get discouraged. You have now joined a rather large group of people that have had cert flights go wrong. For some reason Mr. Murphy loves cert flights more than any other type of launch.
My first cert attempt was last year Level 1 with my sprint, delay blow by and ejectionfired during motor burn.

My reaction was kind of a wow and man that sucks...

Second Level one cert attempt was with my 4" Horizon, thinking maybe I did something wrong with the last attempt building the motor, I double, triple checked the build and had the prefect double check the build.

Liftoff, delay blow by, ejection fired during motor burn...

My reaction that time I was very HOT, that time I knew I did everything right and the flight still went wrong.

Rocket survived that with just a creased body tube, put it right back up on a Pro 38 and certed an hour later.

Yesterday, spent three months on that flight, ground testing everything, double and triple checking everything, scored 100% on my written and was ready to go.

It went to pieces on the pad ...

My reaction wasn't really much of anything, it's like it didn't even surprise me. Went and picked up the pieces and laughed it off, put the Horizon up later without any problems and went on with the day.

Today i'm a little more upset, I still don't know if my electronics are any good i've got to test those yet, but it trashed the rocket, as well as the borrowed casing and my forward closure...

The only, and i mean only bright side is that i've got some pretty good video, when watching it frame by frame it's incredible.

Here's a cuple of pics ....

<img src="https://members.aol.com/firemanup/thorboom.jpg">
I azm sorry to hear that man. I know alot of people who sink screws into those thrust rings because they often fail.
Wow, incrediable shots. I know what you mean about getting upset the day after. I think that happens to most of us, it certainly does to me. When I've had failures like that I'm usually the one clapping and hollering "did you see that", after all what else can you do but pick up the pieces and get back on the horse.
Shame though, you sure did a great job building and painting it.
Wow, that's a spectacular failure. Do you have a dl-able video of it? I hvaen't had a failure yet, but probably will in the near future.
Originally posted by firemanup
The only, and i mean only bright side is that i've got some pretty good video, when watching it frame by frame it's incredible.
As time goes by those pics and video will become priceless to you. You'll probably show that vid to those interested, way more times than a "perfect" flight. And you'll be able to smile about it.
"Endeavor to persevere" :)
Excellent photos fireman. I agree with Stones. As long as the sad even occurred, you might as well have the cool photos. The pain will heal.

Moderators, we need a new forum! 'Grief Counseling'
Sorry to hear about your rocket. That was one pretty bird:( Cool pictures though. Don't give up!
Was this the flight I heard about? The one with the motor arcing over into the ground? From what I've heard that was one interesting launch day. It must not have been as windy there as it was here. It was 25-30mph all day, I have thought about going,but didn't want to drive 10 hours round trip fdor no launching........Larry
Yeh suppose that was my flight... :(

Thanks for all the words guys....

Website is updated.. see the cert attempts page, lots of pictures and 3 short videos.

Waiting to hear from my brother to see how he did today with his Thor, hopefully better news...
Nice pictures and videos. I find the picture of the landed motor and adapter very familar... you used the same type of adapter I did. And it failed exactly the same way mine did.
I must say your documentation was amazing, those pictures are so clear.

It really stinks that such a tiny thing caused so much damage, but from what I have seen you did everything right and this is definantly not an accurate representation of you r building skills.
Well J... at least they're awesome pics and vids! Shrug it off, Bro... look at the bright side... you get to build another Thor.

I didn't get to fly mine today b/c of the wind...
Next month at Whitakers is going to be a kick....
I watched our club's president, Chuck Pierce, have his Thor cato on the pad. He flew it on a hybrid something. His first rocket of the day was a huge Rapier on a L hybrid. About 150 feet off the ground, the grain cracked and the motor burned from both ends I believe, rocket folded in half, and burned on the ground. His next flight was the Thor on another hybrid. 5...4...3....2....1....BOOM!!! Rocket parts went everywhere! That was a nice rocket too. Well, don't give up on L2 and keep at it. My Horizon flew on an H128 with electronics for deployment backup. Boost was good, arced over and nothing came out. It just kept falling. Finally about 100 feet off the ground and at ~100MPH, the parachute deployed, but got tangled. Only damage was a slight wrinkle in the seam on the tube and cosmetic damage. Failure caused by too long delay and inadequate venting of altimeter bay.
Hey Jason,

Matt told me about the mishap - what a bummer! The pictures are incredible though. We were going to try to have three Level 2 cert flights this past weekend at Battle Park in Culpeper but the weather did not cooperate.

So, hopefully I will see you at Whitakers in April and we will ALL GET OUR LEVEL 2 CERTS.
I was just thinking, at least this was an adreniline rush kinda cato. It exploded real quick ya know. At least it wasnt a failed chute where you whatch it and nothing...then it comes down and you think "nooo" as it starts screaming in.
I just looked at the pictures of your Thor...and I think you can fix the booster. First, buy a full length 54mm coupler. Then take a 38mm motor tube and centering rings and center the 38mm tube inside the 54mm coupler. Cut this to the length of your motor tube. Then, glue this entire assembly inside the motor mount. Now you have a 38mm rocket with the motor tube renforced.

After that, drill holes in the 4" tube between the 2 CR's that the body tube crimped. Drill about a 1/2" hole. Fill this entire void with expanding foam from Giant Leap. Now the entire booster should be fixed, if not stronger than it originally was.

Or...just buy some parts and make a new rocket alltogether:)
New Thor kit should be here tomorrow...

There's more damage to the booster than is visible in the pictures, i've found a half inch tear/hole in the airframe a couple of inches above the top centering ring also, besides what's pictured...

I'll just do another and make sure it's done right, already have plans for alterations on the next motor adapter that should take care of any problems there...
Nah no need to glass these kits they're sturdy.

There was no failure to the kit, it was the Loc motor adapter that had a problem, lesson learned and i'll build the next one the way i want to instead of the way the directions show.....