[F-FT] Thoughts on certification

David Erbas-White · 2005-09-22T02:30:55+00:00

Please note that this is intended to be a flame-free thread, I'd greatly appreciate if it could be kept that way.I've had some random thoughts now and then about the certification process, and about the operation of electronic deployment in HPR. As it currently stands, the point of certification is to certify that the user can safely handle larger motors (as part of the purchase requirements), and to correctly deploy a 'nominal' recovery system (generally considered to be a parachute for purposes of certification, but this is by custom, not rule). There is NO requirement to certify that a person knows what they're doing in relation to electronic deployment.In other words, one can 'properly' certify level 1 or 2 without knowing a whit about electronic deployment. I plead guilty to having achieved level 2 without having ever done electronic deployment, AND I AGREE WITH THAT PROCESS. However, as I step up to adding electronic deployment to some of my rockets, and realize how many additional variables that can add, I'm somewhat troubled by the fact that I can do this without absolutely any oversight whatsoever.No, I don't really LIKE oversight, and I'm not suggesting that more bureaucracy is good, but I'm also trying to look out for the future of the hobby as a self-regulated entity. For myself, I'm an electronics engineer, so the electronics portion is not a concern to me. But, for example, the inability to get certain electronic igniters, the problems with properly doing things such as dual deployment, give me pause, and I'm making sure that I talk with folks, read plenty of articles, and watch how others do their deployment before I attempt my own.When I do my first electronics-aided project, I intend to ask the RSO to go over it with a fine-tooth comb -- I don't want any mistakes that might be dangerous, or lose my rocket. But I'm not sure that everyone would do this -- there are an awful lot of shoot-from-the-hip folks out there.So, here's my thought -- what...

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Phil Stein 20 years ago

Kurt,

I may be interpreting this wrong - if I am tell me.

This is not as simple as just making sure the charge goes off. There are considerations like -

How much BP to use, To much you can blow it up. Too little and nothing happens. This is affected by:

Shear Pins - there has to be enough pressure to shear them off.

How tight the couplers to air frame is. Again - you have to make sure you have enough pressure to oversome the friction.

Vents allow some pressure to escape.

There are probably other things I haven't mentioned but I just wanted to make the point that it isn't as simple as lighting an ematch.

Phil Stein

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J.A. Michel 20 years ago

That's the key right there. Read, learn, observe, ask questions. Most people do before attempting to use electronics. Electronic deployment is not hard, but does require some forethought, both in rocket design and recovery system design.

I did my first electronics on my L2 cert flight. I collected all the info I could read, and then designed and built the rocket and altbay. Then, I had some of the guys in my club look my work over carefully and give me a reality check and tell me weather it would work or not.. I also did ground testing to size the charges.

I don't think a separate cert for electronics is needed.

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Howdy 20 years ago

Whether the idea was good or not, the discussion was excellent. Besides the content, it was really cool to learn that you can have a flame-free thread just by saying "this will be a flame-free thread". ;)

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Kevin Trojanowski 20 years ago

Don't apologize, and definitely DON'T go sit in the corner.

Nothing wrong with a good, coherent, mature discussion of a topic.

-Kevin

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raydunakin 20 years ago

Ditto that!

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<randyolb 20 years ago

Here? On RMR? Go outside and feel the ground. ; )

Randy

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Dave Grayvis 20 years ago

What are We looking for? :)

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Kurt 20 years ago

Boy,

That guy is stupid Dave unless he is planning to test stuff in a smaller ship. I mean when I've witnessed L3 flights, they were at an appropriate site in the middle of nowhere. I still wouldn't want to risk possibly over a $1000.00 worth of hardware without trying it on a smaller scale. I guess if an experienced RSO and prefect inspect the ship and it looks airworthy, the guy has the right to take the risk of a launch.

Kurt Savegnago

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Kurt 20 years ago

Hi Phil,

No you didn't mis-interpret me but there are calculators out there that tells one how much BP to use and all the information I have seen recommends ground testing of the charges. I don't think someone would blindly try to do dual-deploy without researching it. I agree it is not so simple.

Kurt Savegnago

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<randyolb 20 years ago

Tundra! ; )

Randy

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Dave Grayvis 20 years ago

Freezing over, I gotcha!

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Kurt 20 years ago

I'll second that at the risk of this being a needless post. I do learn alot from everyone here and I am in an isolated area with little contact with other rocketeers. I have to learn by doing with my L0 models.

Kurt Savegnago

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Phil Stein 20 years ago

The calculators can't take all variables like friction and amount of force to shear a shear pin into account. A calculator is a good start.

Phil

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Kurt 20 years ago

That's why it behooves us to do ground testing, right? :)

Kurt

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Eldred Pickett 20 years ago

The first time I used electronics, I used motor ejection as a backup. I simply made sure I understood which charge did what, and made sure it was wired correctly. I had never used BP, and I was a bit nervous about that. We did a ground test first, then flew it. The electronics and ejection worked flawlessly...

Eldred

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Phil Stein 20 years ago

Yep - definitely.

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[F-FT] Thoughts on certification

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