Ceres 1-X - The Story of my First Real Rocket

[_Augustus_]

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So a few months ago at the end of the school year, I had finally finished my first rocket and my 2 friends and I launched my rocket and their own rockets on Field Day.

I went first. Of course, something had to go wrong.

The launch went perfectly, but after the rocket got about 150 feet up, the engine exploded due to an overpressure event within the fuselage, the motor was faulty and built up air inside.

Like, it looked like Challenger. I didn't think anything survived, but I only lost about 25% of the rocket to the explosion, even though my parachute failed to deploy.

I later determined that the engine slid up through the fuselage and exploded in the middle. It also destroyed 2 wings and knocked off another.

Another friend had filmed the launches on her phone, however she was having problems with the file size due to having a weird phone with a weird camera app or something.

Edited August 24, 2015 by _Augustus_

[Budgie]

Motor explosions are never your fault if you bought the motor from Estes or any of the other major motor sellers, unless you tampered with the engine itself (which is a bad idea and I doubt you did) or kept it in unsuitable conditions. What size motor was it, from which company?

I would say that you should look up the place to call and report the motor issue to the company you bought it from. They like to hear what happened if anything went wrong.

Im curious as to whether the motor sliding up the fuselage was due to your building of the rocket, or due to the motor issue, which would soon result in the explosion.

[_Augustus_]

Motor explosions are never your fault if you bought the motor from Estes or any of the other major motor sellers, unless you tampered with the engine itself (which is a bad idea and I doubt you did) or kept it in unsuitable conditions. What size motor was it, from which company?

I would say that you should look up the place to call and report the motor issue to the company you bought it from. They like to hear what happened if anything went wrong.

Im curious as to whether the motor sliding up the fuselage was due to your building of the rocket, or due to the motor issue, which would soon result in the explosion.

Estes, less than B or C.

It made a screaming noise when it exploded. The motor shell somehow survived, but we didn't go near it.

And my friends (one of whom is in charge of our rocketry club at school that we built this in) both constructed their rockets the same way.

[Kryten]

Do you still have the package, or anything else that might have a batch number? That really sounds like something the Estes company ought to be made aware of.

Edited August 20, 2015 by Kryten

[Budgie]

Do you still have the package, or anything else that might have a batch number? That really sounds like something the Estes ought to be made aware of.

Kryten makes a good point that I should have mentioned. If you're going to write to Estes, which I suggest you do, send them as much information as you can

[_Augustus_]

Do you still have the package, or anything else that might have a batch number? That really sounds like something the Estes ought to be made aware of.

No, my friend bought us the parts because he didn't want us buying them and damaging them or something.

- - - Updated - - -

Okay, here are some photos:

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[Budgie]

Shot in the dark, as I don't know that much about motors. But could it have been some issue with an overly strong ejection charge?

[relin]

Shot in the dark, as I don't know that much about motors. But could it have been some issue with an overly strong ejection charge?

That was my second thought, after a poorly-mounted engine getting loose during flight. I don't think the latter would cause that kind of damage, but an ejection charge might.

[ComradeWolfe]

...but I only lost about 25% of the rocket to the explosion...

My first thought: This man must play KSP!

But really, motor failures can/do occur. If you really want to do an analysis, look to see if there were any parts that might have fallen in to place to cause a blockage after the motor slid up.

Alternately, are you sure it could have slid up? A motor defect may have allowed pressure to vent up in to the rocket middle.

[_Augustus_]

My first thought: This man must play KSP!

But really, motor failures can/do occur. If you really want to do an analysis, look to see if there were any parts that might have fallen in to place to cause a blockage after the motor slid up.

Alternately, are you sure it could have slid up? A motor defect may have allowed pressure to vent up in to the rocket middle.

Now that I think of it, it may have been pressure. The motor flew a bit more after blowing up and exiting the rocket fuselage.

[Aethon]

Well, I used to model rocket much as a lad, back when Hector was a pup... I'm sure Estes tech has not changed much so here's my preliminary crash report.

I'm guessing you were instructed to glue a smaller diameter ring inside the main rocket body, so that your B/C engine will stick out the bottom enough to conveniently install the igniter. Your engine thrust is probably around 14N, so when it launched, the inertia of the rocket on the pad was large enough for the engine to break the glue bond of the interior ring/engine mount that is supposed to keep this from happening. Probably, before the rocket left the pad, the engine had run up the tube, pushing the ring up against the wad, thus lowering the rockets' performance. When the parachute eject charge went off, the engine mount ring, now cross ways in the main rocket tube, blocked much of the force which needed to go somewhere, so it incinerated some of the wad and blew out the side of the rocket slightly below the engine. If you cut the upper tube along the long dimension, I'm guessing you'll find the ring jammed cross ways in the tube, slightly above the engine.

Conclusion: Your rocket was doomed by whoever put it together. My advice... MOAR glue.

Be careful and have fun.

(I once bent down at the launch pad and almost put my eye out on the end of the launch rod.)

Edited August 20, 2015 by Aethon

[_Augustus_]

Well, I used to model rocket much as a lad, back when Hector was a pup... I'm sure Estes tech has not changed much so here's my preliminary crash report.

I'm guessing you were instructed to glue a smaller diameter ring inside the main rocket body, so that your B/C engine will stick out the bottom enough to conveniently install the igniter. Your engine thrust is probably around 14N, so when it launched, the inertia of the rocket on the pad was large enough for the engine to break the glue bond of the interior ring/engine mount that is supposed to keep this from happening. Probably, before the rocket left the pad, the engine had run up the tube, pushing the ring up against the wad, thus lowering the rockets' performance. When the parachute eject charge went off, the engine mount ring, now cross ways in the main rocket tube, blocked much of the force which needed to go somewhere, so it incinerated some of the wad and blew out the side of the rocket slightly below the engine. If you cut the upper tube along the long dimension, I'm guessing you'll find the ring jammed cross ways in the tube, slightly above the engine.

Conclusion: Your rocket was doomed by whoever put it together. My advice... MOAR glue.

Be careful and have fun.

(I once bent down at the launch pad and almost put my eye out on the end of the launch rod.)

No, we had the same size engine and body. My friend knows what he's doing, he's launched rockets 2 miles up.

[Aethon]

So what do you think caused

the engine[to] slid[e] up through the fuselage and exploded in the middle.

?

Do you have a large launch site? If so my advice is :

Get the smallest C rocket you can and build it yourself, following the instructions provided. Nothing will drop your jaw like the altitude you can get out of a tiny C rocket. And if it isn't supplied with a ring/engine mount to glue inside the main tube (I'll eat my [small] hat), make one yourself.

Edited August 20, 2015 by Aethon

[_Augustus_]

So what do you think caused ?

Do you have a large launch site? If so my advice is :

Get the smallest C rocket you can and build it yourself, following the instructions provided. Nothing will drop your jaw like the altitude you can get out of a tiny C rocket. And if it isn't supplied with a ring/engine mount to glue inside the main tube (I'll eat my [small] hat), make one yourself.

I know, but the engine was literally just small enough to fit inside the tube.

We launched them from an artificial field, here. I'm not sure what we'll be doing this school year.

My friend (the guy in charge) launched a relatively large rocket that actually flew all the way over to a driveway at the public housing across the street, and 5 kids volunteered to go grab it.

They looked like a track team O.O

[TheShadow1138]

Just to throw my two cents in, how tightly packed was the wad, and how snuggly was the nose cone? Could the nose be pulled out with ease, that is could it be removed without exerting a lot of force? If the engine's shell survived intact (showing no signs of exhaust exiting the side of the engine) then either the tubing was thinner, or there was some kind of blockage, as has been stated.

[Shpaget]

Every time the engine displacement happened to me was when I knowingly skimped on the Micropore tape in an attempt to reduce the mass and increase the apogee.

The motor would usually go all the way through, ripping through the parachute. It's kind of weird for the motor to get stuck halfway.

[_Augustus_]

Just to throw my two cents in, how tightly packed was the wad, and how snuggly was the nose cone? Could the nose be pulled out with ease, that is could it be removed without exerting a lot of force? If the engine's shell survived intact (showing no signs of exhaust exiting the side of the engine) then either the tubing was thinner, or there was some kind of blockage, as has been stated.

Everything functioned perfectly during drop tests..

[Armchair Rocket Scientist]

No, we had the same size engine and body. My friend knows what he's doing, he's launched rockets 2 miles up.

2 miles? Wow!

What HPR Cert level is he?

[_Augustus_]

2 miles? Wow!

What HPR Cert level is he?

He's too young to get a model rocketry license, so I don't know.

He wants to launch a sounding rocket when he is old enough.

[mellojoe]

Well, I used to model rocket much as a lad, back when Hector was a pup... I'm sure Estes tech has not changed much so here's my preliminary crash report.

I'm guessing you were instructed to glue a smaller diameter ring inside the main rocket body, so that your B/C engine will stick out the bottom enough to conveniently install the igniter. Your engine thrust is probably around 14N, so when it launched, the inertia of the rocket on the pad was large enough for the engine to break the glue bond of the interior ring/engine mount that is supposed to keep this from happening. Probably, before the rocket left the pad, the engine had run up the tube, pushing the ring up against the wad, thus lowering the rockets' performance. When the parachute eject charge went off, the engine mount ring, now cross ways in the main rocket tube, blocked much of the force which needed to go somewhere, so it incinerated some of the wad and blew out the side of the rocket slightly below the engine. If you cut the upper tube along the long dimension, I'm guessing you'll find the ring jammed cross ways in the tube, slightly above the engine.

Conclusion: Your rocket was doomed by whoever put it together. My advice... MOAR glue.

Be careful and have fun.

(I once bent down at the launch pad and almost put my eye out on the end of the launch rod.)

This is my guess as well. Obviously, without any evidence to support it, my theory is that the engine came loose at some point and moved up the rocket body where it shouldn't have. This is probably what caused the cascading failures. Whether the rocket casing itself was burned and caused some kind of overheating event, or whether the eject charge was partially blocked, I don't know. But, my blind, over-the-internet guess is the engine motor wiggled itself loose somehow.