Revision to Tripoli Rule Regarding Wireless Remote Switches

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I have also seen some of the cheap knock-offs (i.e. virtually all of the ones sold on eBay) that can be reversed without a whole lot of effort. I've also seen knock-offs with reversed wires, which is even worse, and with very loose connectors that can pop out or loosen when connected. I get a black Sharpie and mark the sides of black ("-") wires on both sides of the connectors... that way you just have to match the black stripes. And, push the wires inwards to make sure they're 100% seated, and tape the heck out of them so they can't come loose.
 
That's what I've been saying... recovery system safety is about all of the components, not just the altimeter or the switch. You need to look at every single piece and think about what could go wrong with it in flight. That's why I think there needs to be a certification for electronic deployments... if you're new to electronic deployments you need some guidelines so you'll be thinking safety from the get-go.
 
That's what I've been saying... recovery system safety is about all of the components, not just the altimeter or the switch. You need to look at every single piece and think about what could go wrong with it in flight. That's why I think there needs to be a certification for electronic deployments... if you're new to electronic deployments you need some guidelines so you'll be thinking safety from the get-go.
1000% agree. I'm building my first e-bay and I've spent waaaaay more time researching electronics, batteries, sled designs, connectors, wiring, switches, etc than I did researching building techniques when building my L1 rocket. IMO it's not that complicated but details certainly matter, at least to me they do. Every single component must work correctly to have a successful flight. It's a deployment system, not just an altimeter.
 
Yeah, I'm talking about cheap knock-offs, which seem to be the default. I've taken to plugging the two together correctly, then coloring the "top" side of both male and female with a sharpie. Then I just make sure the sharpie sides (or the non-sharpie side) match up when I connect. Either side can be "top", doesn't matter as long as they're connected properly when you mark.
 
Yeah, I'm talking about cheap knock-offs, which seem to be the default. I've taken to plugging the two together correctly, then coloring the "top" side of both male and female with a sharpie. Then I just make sure the sharpie sides (or the non-sharpie side) match up when I connect. Either side can be "top", doesn't matter as long as they're connected properly when you mark.
You've got the right solution given the available product and quality level!
 
I think another cert level for electronics is a bad idea. It would complicate cross certification with NAR and unless you want to go to L3, electronics aren't required. I could see an endorsement on cert levels like L2 with staging or L1 with electronic deployment but I'm failing to see a benefit to those without restricting the base cert levels which is something I wouldn't want to do.

There are many different solutions to the switch issue but adding more restrictions is not a good one in my eyes.
 
I think another cert level for electronics is a bad idea. It would complicate cross certification with NAR and unless you want to go to L3, electronics aren't required. I could see an endorsement on cert levels like L2 with staging or L1 with electronic deployment but I'm failing to see a benefit to those without restricting the base cert levels which is something I wouldn't want to do.

There are many different solutions to the switch issue but adding more restrictions is not a good one in my eyes.
Well said, and +1.
 
I think another cert level for electronics is a bad idea. It would complicate cross certification with NAR and unless you want to go to L3, electronics aren't required. I could see an endorsement on cert levels like L2 with staging or L1 with electronic deployment but I'm failing to see a benefit to those without restricting the base cert levels which is something I wouldn't want to do.

There are many different solutions to the switch issue but adding more restrictions is not a good one in my eyes.
We could quibble about whether electronic deployment requires a separate certification or whether L1 and L2 SHOULD have more training in awareness in its use. There are L1 and L2 flights that are using electronic deployment today. I'd rather people have better awareness of what to do, and equally important what NOT to do when creating an electronics bay. Again, this could be training within a certification or outside of a certification. I don't care. I DO care about some of the work I've seen from people who can't solder well and have no idea about thinking ahead to failure mechanisms. People can and will get hurt from that.
 
What if the L2 exam just included some specific questions covering safe design practices and launch/prep procedures related to electronic deployment?
 
I think there is a lot more risk in someone’s first dual deploy flight than there is flying an H instead of a G80. It’s much more than just the electronics too. I’ve seen two flights where someone left out the charge AND the delay grain when building the motor because they thought it wasn’t needed with electronic deployment.

A “cert” flight or whatever you want to call it with a little extra help from the RSO or a mentor would be beneficial for everyone. As long as it isn’t required for L1 (and the reverse) the impact would be pretty minimal.
 
I started using electric deployment in MPR with an E motor, well before I got L1 and L2. We don't need more rules and certifications.

Training for soldering? Watch a YouTube video. Done.
 
I don’t like the idea of additional certifications, but I agree that there needs to be better understanding of electronics and basic wiring practices.
I could see adding a section on electronics to the L2 written test, but it would have to be done in unison with CAR and NAR. All motors above a 2560 Ns are required to have electronic recovery so that would fit.
But it sounds like the biggest problem with electronics is getting people not to use junk. I don’t think we can do much about that.
 
We could quibble about whether electronic deployment requires a separate certification or whether L1 and L2 SHOULD have more training in awareness in its use. There are L1 and L2 flights that are using electronic deployment today. I'd rather people have better awareness of what to do, and equally important what NOT to do when creating an electronics bay. Again, this could be training within a certification or outside of a certification. I don't care. I DO care about some of the work I've seen from people who can't solder well and have no idea about thinking ahead to failure mechanisms. People can and will get hurt from that.
I find no issue with the saying that people need more knowledge and training but requiring it is not something I'd support. Adding a section to the L2 test would not be too intrusive but again, the first time they're actually required is for L3 so requiring knowledge or skill before L3 should not be mandatory.
 
L motors are required to have electronic recovery.
Beg your pardon? I can't fly an Aerotech L1000 with apogee motor ejection?

It's true that most other L motors are plugged, but not this one.
 
Back to the rule, I think they should have simply said that "There must be two independent switching devices (altimeter, timer, electronic or physical switch, etc.) between a power source and an energetic, at least one of which must physically disconnect power." That takes care of about 99% of the "But what about..." questions. If they later decide to allow electronic switches in lieu of physical ones, they can remove the "at least one of which must physically disconnect power" clause. It's always easier to remove a restriction than to add one.
 
Beg your pardon? I can't fly an Aerotech L1000 with apogee motor ejection?

It's true that most other L motors are plugged, but not this one.

You can, but you must also have electronic deployment. Here’s the rule from NFPA 1127:

4.10.2 A high power rocket launched with an installed total impulse greater than 2560 N-sec (576 lb-sec) shall use an electronically actuated recovery system as either a primary or backup deployment method.
 
Back to the rule, I think they should have simply said that "There must be two independent switching devices (altimeter, timer, electronic or physical switch, etc.) between a power source and an energetic, at least one of which must physically disconnect power." That takes care of about 99% of the "But what about..." questions. If they later decide to allow electronic switches in lieu of physical ones, they can remove the "at least one of which must physically disconnect power" clause. It's always easier to remove a restriction than to add one.

I like that.
 
At the weekly 'rocket lunch' I attend one of the guys bought a sample of a screw switch he and others decided to try in light of the recent rule. I wanted to design and print a 3D mount for it since it needs some clearance on the bottom. While I had it, I tried the experiment you see below. I repeated it several times. Sometimes it turned clockwise, sometimes the reverse. The altimeter I used is a Perfectflight Stratalogger with the optional connection for a LED. I cropped and resized the video so I could make it an animated GIF for simplicity.

This is a simple experiment anyone can try for themselves.


Tony

(full video available on request)
switch-test.gif
 
You can, but you must also have electronic deployment. Here’s the rule from NFPA 1127:

4.10.2 A high power rocket launched with an installed total impulse greater than 2560 N-sec (576 lb-sec) shall use an electronically actuated recovery system as either a primary or backup deployment method.
Any idea why that rule is there? As listed above, there are (admittedly very few) L motors with delays and ejections.
 
You can, but you must also have electronic deployment. Here’s the rule from NFPA 1127...
Huh. This is a good example of why the TRA Safety Code should have more detail in it than expecting you to read a long document that is difficult to access. I bet that almost no one was aware of that rule, I certainly wasn't. I wonder how many other little gotchas are waiting to be discovered.
 
At the weekly 'rocket lunch' I attend one of the guys bought a sample of a screw switch he and others decided to try in light of the recent rule. I wanted to design and print a 3D mount for it since it needs some clearance on the bottom. While I had it, I tried the experiment you see below. I repeated it several times. Sometimes it turned clockwise, sometimes the reverse. The altimeter I used is a Perfectflight Stratalogger with the optional connection for a LED. I cropped and resized the video so I could make it an animated GIF for simplicity.

This is a simple experiment anyone can try for themselves.


Tony

(full video available on request)
View attachment 406603
Was that tightened fully (or backed out fully) first? I know that switch well, I find it hard to believe it would go intermittent so easily, unless the screw was closed very lightly.
 
Huh. This is a good example of why the TRA Safety Code should have more detail in it than expecting you to read a long document that is difficult to access. I bet that almost no one was aware of that rule, I certainly wasn't. I wonder how many other little gotchas are waiting to be discovered.
Also, NFPA 1127 is not publicly available, unless you pay for it. I would bet that a good number of L2's have never seen the actual code, just the restatements from the L2 test pool.
 
Also, NFPA 1127 is not publicly available, unless you pay for it. I would bet that a good number of L2's have never seen the actual code, just the restatements from the L2 test pool.

We sent a copy to every Prefect a couple years ago. It would be nice to be able to afford to provide one to every member, but they’re $52 each now.
It is accessible at no charge online though, even though that’s less convenient.
 
At the weekly 'rocket lunch' I attend one of the guys bought a sample of a screw switch he and others decided to try in light of the recent rule. I wanted to design and print a 3D mount for it since it needs some clearance on the bottom. While I had it, I tried the experiment you see below. I repeated it several times. Sometimes it turned clockwise, sometimes the reverse. The altimeter I used is a Perfectflight Stratalogger with the optional connection for a LED. I cropped and resized the video so I could make it an animated GIF for simplicity.

This is a simple experiment anyone can try for themselves.


Tony

(full video available on request)
View attachment 406603
Bad implementation of a screw switch.
 
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