Multi-Stage question

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Mike

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A finally got round to launching my first multi stage rocket, the bosster stage drove the rocket into the wind and then at seperation the rocket went in a new direction during the upper stage. I'm guessing that this was because the ignition of the upper stage was slow or the rocket was not travelling fast enough at seperation.

Please could someone give me a few hints on how I could improve this in future?

The original was 24mm and flew on C6-0 to C6-7, there was quite a gap between the two motor so could this be a cause of the slow upper ignition?

Thanks in advance
 
hmmmm.... you say the original was 24mm and you used a C6-0 to a C6-7..... assuming that you used Estes engines, then the C6-0 and C6-7 are 18mm engines.... unless you used adapters to adapt the 18mm engines to the 24mm motor tubes.

At any rate, I think one of the key issues here is... how much does this rocket weigh? It will help us greatly to know the weight ready to launch - in other words, all prepped, both stages, with engines, parachute, etc.

Also, what were the wind conditions at launch? What was the wind speed, and was the wind coming fairly steady from one direction, or was it gusting from variable directions?

This is just a guess, mind you, but I am betting that you have a fairly heavy rocket (for the engines used) and that there was at least some amount of wind.....

Give us a bit more info, and we'll be able to give you better advice.
 
Mike,

Something to look for when multi staging and there is a gap.

You need vent holes someplace along the gap between the upper and lower stage...I know it sounds counter productive...this is to relieve some of the pressure from the lower stage fuel "breakthrough" so that particles of burning fuel are contained long enough for them to ignite the upper stage.

But, like Ken said, "we need more information".

sandman
 
OK guys as you requested, more info -
Empty Weight: 23g
Launch Weight: 71g
Rocket Length: 550mm
Wind at launch: About 5mph in gusts but in the same direction. I angled the pad to compensate for the wind.
Rocket is proven stable (2.62 calibers)
It had vent holes.
The motors were in motor tubes with clips centered inside the 24mm body tube.

I think if given you all that you needed. Maybe it was just an odd launch?
 
Perhaps 2.62 calipers was a little too stable and rocket speed could not compensate for wind...pure speculation.

I have found that angleing the launch rod to compensate for the wind is sometimes counter-productive on launch but, it does help bring the rocket back a bit during recovery...if you're lucky.

Like I said earlier, pure speculation, it may just have been a fluke.

Try it again. It seems that you have been doing everything right.

Sometimes bad things happen to good rockets!

sandman
 
Thanks for your help, I'll try it again soon.
 
I'm with Sand. I'd wager that a good part of the issue is angling the rod into the wind. I lost my Aspire that way. Put it up on a D12 and it went up straight as an arrow, but I had to walk a ways to get it. I angled it about 5 degrees into the wind for an E9 launch and it weathercocked like crazy. Had there been a 2nd stage, it would have launched horizontally.
 
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