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Only 1 out of 3 succesful launches yesterday.

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ascastil

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First launch was my QCC Explorer on a D12-5. Shock cord came undone with the Kevlar line. No damage to the rocket though. Fell back to earth horizontal and recovered it and the nose cone with parachute. Tied everything back up and had one more succesful launch.

Maiden voyage of my Aerotech Gforce on a G40-4. Body tubes didnt separate and it lawn darted into the hard desert dirt. It was obviously destroyed. I have a possibility of what went wrong. I built this rocket months and months ago. I thought it was all finished but after inspecting at home after the crash, I noticed the top centering ring on the motor mount was only glued to the plastic bafffle. I didnt have a ring of glue around the body tube. Im wondering if there was any way some the ejection gasses escaped further down to the bottom of the body tube and not having enough to separate the body tubes. I found the top centering ring was not even attached after the crash but I think the force of impact jarred it loose. It was attached before flight. I have cut the rocket all apart and salvaged the motor mount and centering rings, launch lugs, and fins, parachute and shock cord. Im going to order the 2 body tubes and nose cone and rebuild it.

I got some pretty funny video of the launches. Ill try and post them. I had some bad luck, but we all had fun. I think Im just going to have to practice because I havent had a launch in a year or two.

[video=youtube;benTQsdgQUw]https://www.youtube.com/watch?v=benTQsdgQUw[/video]

[video=youtube;ao9z6H0vt4A]https://www.youtube.com/watch?v=ao9z6H0vt4A[/video]

I get a little emotional on the Gforce crash, the QCC video was funny. We all had a good laugh watching it afterwards.
 

The_Lone_Beagle

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Oh man...well, an a positive note, the *launch* of the G-Force was beautiful!
 

Handeman

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If that top ring wasn't sealed to the BT, that could certainly contribute to what happened. I think I've seen more failed ejections on the GForce than any other rocket. I think AT designed the biggest rocket they could for G motors and it turned out to be very marginal on ejections with the amount of BP supplied with their G motors.

I always recommend adding BP to the ejection charge when you fly a Hobbyline motor in a GForce. Guess that doesn't help now.... Just remember, you weren't the first nor will you be the last to have that happen.

Good luck on the rebuild.
 

ThirstyBarbarian

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I think another thing that happens with the GForce is that the coupler can bind inside the booster section. I think the volume is small enough that a standard charge should be enough to pressurize it for a successful ejection, and the main reason it fails is due to binding. I tried to make the surfaces as smooth as possible. I coated the inside of the booster half of the recovery bay with thin CA to harden it. And then I sanded it smooth. It's a bit of work, but it makes the surface very smooth. I also put a bit of thin CA on the lip of the coupler on the upper section and then sanded the lip to a slight bevel. It helps to prevent that lip from getting frayed, and makes it easier to get the coupler started into the booster section tube when putting the two halves together.

Good or luck with the rebuild. That must have been a sad moment when it crashed. I feel your pain!
 
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ascastil

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I can, or could, hold the rocket by the nose cone and half of the coupler would slide out of the bottom body tube. Do you think it needs to be looser? The motor was a single use and stayed in the motor mount the hole flight.
 

ThirstyBarbarian

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Also, I do not use the cooling mesh inside the motor tube baffle. That seems like it could potentially clog the pathway and weaken the ejection charge. I use a nomex chute protector.
 

ThirstyBarbarian

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I can, or could, hold the rocket by the nose cone and half of the coupler would slide out of the bottom body tube. Do you think it needs to be looser? The motor was a single use and stayed in the motor mount the hole flight.
That sounds loose enough to me.
 

fyrwrxz

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That sounds loose enough to me.
More cowbells,er, black powder! I also burnished the faying surfaces with graphite powder on my G-force (BlackOut) after the first flight flat spun in. (H-165)
 
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ascastil

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I have a 29mm AT casing Ill use on the next flight whenever that is. Ill just use more blackpowder. Ive never added more so Ill have to learn. Only used a single use this time because I could get it local and it was kinda like "lets go launch rockets" idea.
 

The_Lone_Beagle

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I can, or could, hold the rocket by the nose cone and half of the coupler would slide out of the bottom body tube. Do you think it needs to be looser? The motor was a single use and stayed in the motor mount the hole flight.
That should have been good enough. Handeman is right, I do recall reading a lot about failed G-Force ejections/deployments on here a while back.
 

Mr Rocket

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I had the same failure on my QCC Explorer on its last flight. Unfortunately the flat spin had a rotation to it, and hit the parking lot hard. Cracked one fin in half, put hairline cracks in 2 others, and knocked out a 1/8"X1" chunk of the air intake. Nose cone landed on the shore of "Lake Woebegone". Whew!Recovered all parts and it is in the workshop getting ready to fly again.
 
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dixontj93060

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I get a little emotional on the Gforce crash, the QCC video was funny. We all had a good laugh watching it afterwards.
Far more than rockets or rocket failures shown on those videos. The laughs and shrieks show what it's really about--family and fun times.
 

ascastil

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It was fun. Maybe that was the spark I needed to keep at the hobby. I always get sidetracked with car projects that turn into 1 year modifications lol. I did drag a damaged Initiator out of the closet and ordered a fin for it. Ordered the parts to repair the Gforce. Im finishing up a Hi Flier XL and an Aerotech Strong Arm. Ordered 4 reloads, E18 and G64. Plus I have an F24 and E18 stashed away. Planning another Christmas launch with 7 rockets!
 
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