Beware of the Chuff

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Rex R

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Beware of the chuff.
like many I had heard that cti motors would either light or they would not, there is no chuff. This is not true. They do on rare occassions chuff. Sunday Sep 20 I prepped my priority stealth 29mm for what turned out to be its' last flight. I 'assembled' a cti G33-9 mellow yellow as per instructions and slid the 'starter' in until it made contact with the starter pellet then placed the nozzle cap on the nozzle. Filled out the flight card and proceded to rso & lco. After being approved I took it out to the pad etc., waited for the lco to run through the count down and push the red button. From there things went pear shape. The motor apparently had a 'hard chuff' which was enough to propel the rocket up 4' of rod when the motor experienced a lack of thrust, the rocket went another few feet up and then fell toward the ground. At some point either on the ground or just above it the motor 'relit', hit a leg of the pad, took one or more bounces and then proceeded to head toward the flightline/lco table. it hit a spectator, the motor landed roughly 100 yards away. the wounded spectator needed 17 stitches.
Speculation/guess, I suppose that it is possible for the starter pellet to wind up in the wrong place due to an error at cti, probably never know, but that Might explain the chuff. If your motor chuffs and apparently goes out give it a least a minute after it stops smoking before approaching the rocket, it might just light at the wrong time!
Rex
 
yes he is. since he isn't making a big fuss at the moment, I thought I would return the favor. I heard that the ER was busy that day (NOT from rocketeers).
Rex
 
I had to leave at about 12:30 that day, and missed it. I seem to recall another aborted launch that morning where the starter pop lifted the rocket visibly off the pad. That one stayed put, though.
 
or to put it another way, once THE BUTTON is pressed, Mr. rocket is no longer your friend. this took place somewhere between 14:30 and 15:00. not how I wanted to spend my orbit day.
Rex
 
Hopefully, he has a full recover.

It is a potentially dangerous hobby. It is good to be safe but often I wonder how much of it is luck. I have seen some chuffs that end up cruise missiles or land sharks. All they have to do is head in the wrong direction.
 
figured that it might be a good idea to remind folks that things don't always go according to plan.
Rex
edit
also found out that 1.5" pvc pipe will break if you hit it right.
 
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Yikes! To date, I have not seen anyone get injured at a lunch (except maybe a pinched finger setting up equipment or something). I hope you are well, whoever you are!
 
Ouch! Glad the injury wasn't worse, but 17 stitches is no fun.

Since the injured party didn't approach the rocket, I guess the lessons for future launches are:

a) If a chuff leaves the pad, the LCO/announcer should tell the crowd keep an eye on it for 60 seconds, get out of the line of fire, the LCO should not launch anything else in that time
b) Even if you don't get told (a), you should and tell people around you as well.
c) check location of the powder pellet when you open CTI motors to adjust delay just in case.

Is that fair? Is there something else to learn?

"Learn from other people's mistakes. You won't live long enough to make them all yourself." --Mark Twain
 
I was standing next to the guy who got injured when this happened. It was very strange as the rocket sat on the ground for 3-4 seconds (seemingly dead) before it took off again. This could happen to anyone, and stands as a reminder that accidents can happen. I'm not a propellant guy, so I can't really speculate as to what happened with the motor.

I would suggest as a follow up, to make sure clubs have good first aid materials, and check what they have in stock. Most launches are out in the boonies, and you never know when you have to treat things like this, or sprained ankles, bad sunburns, etc.

I had to leave at about 12:30 that day, and missed it. I seem to recall another aborted launch that morning where the starter pop lifted the rocket visibly off the pad. That one stayed put, though.

This probably was our rocket- we had one on the rails that blew the rear closure (AT 24/40 case) and lifted up about 2 feet and then slid back down the rail.
 
sterile gauze/ water(although bottled water will do in a pinch). the rangers did suggest that the club invest in some clotting agent. first aid kits need to be checked at a minimum of once a year for expired items, damaged packaging, missing items, etc.
Rex
 
sterile gauze/ water(although bottled water will do in a pinch). the rangers did suggest that the club invest in some clotting agent. first aid kits need to be checked at a minimum of once a year for expired items, damaged packaging, missing items, etc.
Rex

Everybody should have some CA glue on hand. :wink:
 
I wouldnt get a clotting agent as the rates of injury at rocket events that would require it are so minuscule. PLUS it's expensive and has a limited shelf life. Depending on where you're at obtaining it may take a prescription and using it would be a huge liability (who's trained, how trained, who's the medical control)

I have the METRA first aide kit, it's a standard 40 person kit. The most frequent treatment is for blisters, then self inflicted lacerations (read: dangerous with a knife). None of which has even required a stitch, knock on wood.

As a FF/EMT we don't even carry clotting agents. YOu would be surprised on how much bleeding can be stopped/slowed with some 4x4s and gauze.
 
" YOu would be surprised on how much bleeding can be stopped/slowed with some 4x4s and gauze. "

Would that be the Douglas fur or pressure treated type?
 
OK,
I'll admit that it was me that got attacked and bit by the landshark. As it popped off the pad and landed on the ground, I thought, "Don't light!!". As this thought was running through my head, it lit and at 35-40ft, there was no way I could get out of the way in time (the old reflexes ain't what they used to be). It hurt a bit. They sat me down and decided we should pull up my pant leg and look at it. By this time the blood spot was about 4" round. That's when my day ended and they decided to cart me off to the ER.
45 minutes wait in the ER, then they decide to actually look at my leg. The poor little hospital ER was VERY busy that day. They had 10 rooms and all were full. They put me on a cot in the hallway, and 45 minutes later they cleaned it and stitched me up, still in the hallway, which took another 45ish minutes. All together we were at the hospital for around 3 hours. I finally got home to Malta around 10pm. We went into the ER at 3:30pm. My son came over after school and unloaded the car for me. I went to my own Dr Tuesday, and she looked at it and said, "Ewww," or words to that effect. I went to see her again last Friday, and have to see her again this Friday. She wants to leave the stitches in for 3 weeks if possible, as my shin skin is very delicate (a pre existing condition). A slight bump and I skin my shins. This could have been much worse, as my 8yr old son was standing right next to me, and it could have hit him or any of the other kids standing nearby. A week off of work, keeping my leg elevated and not moving around much.
So I went to work today and got along fine. I had three layers of protection on my leg, two gauze pads and a elastic wrap. The wound leaked a little more today than it did yesterday, but I was moving around a lot more. I'll have a nice scar, and bone bruise for while, but as I said, it could have been much worse. It could have gained altitude and hit someone in the head or something along those lines...
Net result is, I'll live to fly another day.
If you guys want, I'll post a picture of the cut, but be warned; my legs never see the Sun :y: oh and the wound is pretty gruesome too.

As an aside, the lovely lady who stitched me up also stitched up a dude who cut his thigh with a chainsaw. He came in after me and was taken in before me (maybe in state has preference... :p )
I asked her which wound was worse. Her reply was "Yours by far". So I won the ugly cut of the day award :eyepop: not by choice...
At the end of all this I'll say; it was an accident. Crap happens. I just stepped in it the most that day.

Adrian
 
Ford or Chevy? Dodge doesn't count (that's for you Gus...) :wink: :eyeroll:

Adrian

I bet after I drive over you with my F350 you won't be bleeding anymore......promise it will stop by the time I get the rear wheels over you :y:
 
OK,
I'll admit that it was me that got attacked and bit by the landshark. As it popped off the pad and landed on the ground, I thought, "Don't light!!". As this thought was running through my head, it lit and at 35-40ft, there was no way I could get out of the way in time (the old reflexes ain't what they used to be). It hurt a bit. They sat me down and decided we should pull up my pant leg and look at it. By this time the blood spot was about 4" round. That's when my day ended and they decided to cart me off to the ER.
45 minutes wait in the ER, then they decide to actually look at my leg. The poor little hospital ER was VERY busy that day. They had 10 rooms and all were full. They put me on a cot in the hallway, and 45 minutes later they cleaned it and stitched me up, still in the hallway, which took another 45ish minutes. All together we were at the hospital for around 3 hours. I finally got home to Malta around 10pm. We went into the ER at 3:30pm. My son came over after school and unloaded the car for me. I went to my own Dr Tuesday, and she looked at it and said, "Ewww," or words to that effect. I went to see her again last Friday, and have to see her again this Friday. She wants to leave the stitches in for 3 weeks if possible, as my shin skin is very delicate (a pre existing condition). A slight bump and I skin my shins. This could have been much worse, as my 8yr old son was standing right next to me, and it could have hit him or any of the other kids standing nearby. A week off of work, keeping my leg elevated and not moving around much.
So I went to work today and got along fine. I had three layers of protection on my leg, two gauze pads and a elastic wrap. The wound leaked a little more today than it did yesterday, but I was moving around a lot more. I'll have a nice scar, and bone bruise for while, but as I said, it could have been much worse. It could have gained altitude and hit someone in the head or something along those lines...
Net result is, I'll live to fly another day.
If you guys want, I'll post a picture of the cut, but be warned; my legs never see the Sun :y: oh and the wound is pretty gruesome too.

As an aside, the lovely lady who stitched me up also stitched up a dude who cut his thigh with a chainsaw. He came in after me and was taken in before me (maybe in state has preference... :p )
I asked her which wound was worse. Her reply was "Yours by far". So I won the ugly cut of the day award :eyepop: not by choice...
At the end of all this I'll say; it was an accident. Crap happens. I just stepped in it the most that day.

Adrian


At least your going to survive, heal quickly.
 
60 seconds wait may not be enough...
[video=youtube_share;eeF_DvkMZjo]https://youtu.be/eeF_DvkMZjo[/video]
 
I feel bad for how much I just giggled. My mom looked at me weird when I was just giggling endlessly, I guess some people don't get rocket humor....

"Well... that's down to about a G motor now..."
 
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