Revision to Tripoli Rule Regarding Wireless Remote Switches

[Grandpa$]

Indiana Rocketry had a launch last weekend and we implemented the new rules.

I observed that speaknoevil followed the rules. His description is accurate.

Admittedly most of the launches we had this weekend used mechanical switches. At our next launch our plan is to have a "Post RSO" table. This would be a secure area past the flight line where wireless systems could be turned on.

Example.
The rocket would leave prep area with switch off, electronics off to the RSO.
After inspection carried to Post RSO area with switch off, electronics off.
At the Post RSO table, switch is turned on, electronics still off.
When vertical at launch pad, turn electronics on.

Steve, would that meet your "Although the rocket must be pointed in a safe direction at all times, it is not required to have the rocket on the pad and vertical when the mechanical connections are made if the wireless remote switch is in its safe state."

Thanks, Richard Cash
Prefect Indiana Rocketry

 

[Steve Shannon]

Indiana Rocketry had a launch last weekend and we implemented the new rules.

I observed that speaknoevil followed the rules. His description is accurate.

Admittedly most of the launches we had this weekend used mechanical switches. At our next launch our plan is to have a "Post RSO" table. This would be a secure area past the flight line where wireless systems could be turned on.

Example.
The rocket would leave prep area with switch off, electronics off to the RSO.
After inspection carried to Post RSO area with switch off, electronics off.
At the Post RSO table, switch is turned on, electronics still off.
When vertical at launch pad, turn electronics on.

Steve, would that meet your "Although the rocket must be pointed in a safe direction at all times, it is not required to have the rocket on the pad and vertical when the mechanical connections are made if the wireless remote switch is in its safe state."

Thanks, Richard Cash
Prefect Indiana Rocketry

That’s a perfect implementation. Thank you!

 

[manixFan]

Of course there is a website called ferrulesdirect.com! That is a high degree of specialization. Thanks for the link.


Tony

 

[g.pitts]

Depends on the tool... this is the one I bought... $64-ish.

I have no idea if that’s spendy in a hobby where you have rockets named ”40 dollars a second.” (Love that name, by the way)

Ironically, I have a hydraulic crimper for 0-awg wire that’s cheaper than the one for 26AWG in my pictures.

A JST crimp tool I checked out - very briefly - was over $600. Needless to say, I passed on that "investment".

 

[rocket_troy]

A JST crimp tool I checked out - very briefly - was over $600. Needless to say, I passed on that "investment".

Yikes, does it come with a free Tantalum watch?

 

[jbr]

crimping for this application that will only be used 10 to 100 times is ridiculous
especially if you are crimping the igniter or ematch leads
and tools don't need to be expensive
https://www.amazon.com/gp/product/B0069TRKJ0
https://www.amazon.com/gp/product/B07476C1LD
https://www.amazon.com/gp/product/B073TZ5BBG/

I needed all these to custom build a 3d printer

 

[wsume99]

crimping for this application that will only be used 10 to 100 times is ridiculous
especially if you are crimping the igniter or ematch leads
and tools don't need to be expensive
https://www.amazon.com/gp/product/B0069TRKJ0
https://www.amazon.com/gp/product/B07476C1LD
https://www.amazon.com/gp/product/B073TZ5BBG/

I needed all these to custom build a 3d printer

I bought the exact same ferrule crimper and a JST crimping kit too when I installed some relays on my 3D printer that are controlled by a pi. I was hesitant because they are obviously of Chinese origin but there were a ton of positive reviews so I went for it. I got a Klein crimping tool from HD instead of the Chinese version off Amazon. It was actually cheaper IIRC and it's a very reputable brand. Bottom line, if you look around you can avoid large bills on tools, especially ones you may not use all the time.

 

[Frederocket]

View attachment 406953 View attachment 406952 View attachment 406953 View attachment 406953 View attachment 406952 View attachment 406953

It actually looks like the one from Missleworks. They are #6 screws. The screw thread is loose. Other than that the PCB is of high quality. As I posted a many pages back, you can save yourself from any screw loosening or closing by using VC-3 Vibra-tite resin.

Just got some VC-3 this past weekend, works like a charm. I also removed the screw that comes with the Missle-Works switches, replaced them with 6/32 x 5/16 screws. Just finished the installation on my Wildman Shape-Shifter, (surface mounted).

 

[ksaves2]

Sorry, Kurt, I was eating a New York strip with my family for Valentine’s Day.
Once you’ve cleared the RSO you head out to the range. There could be a table ahead of the flight line or off to the side but away from the spectators where you stop and reconnect your battery. Then you continue out to the pads.

That's acceptable as long as people aren't around so the nosecones can be pointed in a safe direction. If the above wasn't acceptable, a lot of smaller rockets with electronics and no through wall switches would be unflyable.
It's no rocket science to make sure one's electronics are functional the day before a launch. If one bench tests with contained ematches the day before, the defective device that blows when power is turned on will be eliminated if the ematches don't pop.

I've done a lot of switchless mag switches and wireless without issue with batteries connected but with the mag switch turned off before going to the RSO table. The thing here is with the devices turned off, one can't tell without opening up the rocket so it's the builders word. I'll change to conform though. Kurt

 

[g.pitts]

crimping for this application that will only be used 10 to 100 times is ridiculous
especially if you are crimping the igniter or ematch leads
and tools don't need to be expensive
https://www.amazon.com/gp/product/B0069TRKJ0
https://www.amazon.com/gp/product/B07476C1LD
https://www.amazon.com/gp/product/B073TZ5BBG/

I needed all these to custom build a 3d printer

The stories I could tell you about manufacturing issues in a PRC factory that originated because of counterfeit tooling...

 

[Viperfixr]

Is there a "new rule for dummies" version that keeps things simple?

Honestly, I haven't paid much attention to this as I was moving across the country and unable to participate in rocketry. As I am about to get back into flying rockets again, I read this thread...and a few of the pages more than once. Even after this review, and I don't know if I am the only one, but I am honestly more confused that before. So many iterations mentioned here that I lost track of what was and was not allowed anymore.

Sounds like my MW & Featherweight screw switches are allowed, and my Featherweight Perch is not without modification. And, if I use the Eggtimer Wifi switch in my electronics pile, I have to install a screw switch or similar to physically disconnect power until after the RSO table review. Most of my av-bays use 3D printed sleds with schurter or MW/FW screw switches (accessible thru a hole in the airframe, enabled only on the pad when vertical), and hopefully those are all still "good". Is that all about right?

 

[SDramstad]

This thread is more contorted then a constipated boa constrictor. It boils down to this. No energized electronics anywhere in the path to the ejection charges until you are either at the pad or at a designated area. It is no more complicated then that.
Steve

 

[GlueckAuf]

This thread is more contorted then a constipated boa constrictor. It boils down to this. No energized electronics anywhere in the path to the ejection charges until you are either at the pad or at a designated area. It is no more complicated then that.
Steve

The only part I remain uncertain about is the difference in procedures for an “approved” remote switch vs. a “not yet approved” ( eg Featherweight magnetic) switch.

Good skies,
GlueckAuf

 

[Nytrunner]

Steve mentioned that the "approved switches" portion of the original post was a sidebar issue and is not a component of the new mechanical disconnect rule

 

[GlueckAuf]

Steve’s reply to me in post #503 allayed my fear, uncertainty, and doubts whether or not my Level 3 design candidate was viable or not—it uses two Featherweight mag switches, and IS okay with proper power activation/pyro connection procedures—I just don’t clearly understand what one can do with an approved switch that one can’t with an approval-pending switch.

Good skies,
GlueckAuf

 

[Steve Shannon]

Steve’s reply to me in post #503 allayed my fear, uncertainty, and doubts whether or not my Level 3 design candidate was viable or not—it uses two Featherweight mag switches, and IS okay with proper power activation/pyro connection procedures—I just don’t clearly understand what one can do with an approved switch that one can’t with an approval-pending switch.

Good skies,
GlueckAuf

GlückAuf,
With the “approved wireless remote switches” you can restore power to the wireless switch (but no further) before you raise your rocket vertical. That way you can back away from the rocket and turn on your avionics from a safe distance instead of being on a ladder.
I expect (desperately hope) we’ll get rid the whole approval aspect. The important thing is that those remote switches allow you to be some distance away when you turn on power to avionics.

 

[manixFan]

This thread is more contorted then a constipated boa constrictor. It boils down to this. No energized electronics anywhere in the path to the ejection charges until you are either at the pad or at a designated area. It is no more complicated then that.
Steve

Unless I have misunderstood what has been widely discussed in this thread, I can have energized electronics as long as I have an 'air gap' between the electronics and the charges. So I can continue to use my magnetic or wifi switches exactly as designed, as long as I can break the connection between the electronics and the charge. I even illustrated how I 'twist and tuck' my charge leads, which seemed to be met with approval.

In post 503 Steve seemed to agree with the 'or' of [no power to electronics], or, [no connection to the charges].

So, maybe a bit more complicated than just no energized electronics.


Tony

 

[Steve Shannon]

Unless I have misunderstood what has been widely discussed in this thread, I can have energized electronics as long as I have an 'air gap' between the electronics and the charges. So I can continue to use my magnetic or wifi switches exactly as designed, as long as I can break the connection between the electronics and the charge. I even illustrated how I 'twist and tuck' my charge leads, which seemed to be met with approval.

In post 503 Steve seemed to agree with the 'or' of [no power to electronics], or, [no connection to the charges].

So, maybe a bit more complicated than just no energized electronics.


Tony

You’re correct, Tony. Either open physically somewhere before avionics or between avionics and charges.

Here’s the actual text from the first post:

This revision, which takes place immediately, requires that all devices which control staging or energetic charges must be physically disconnected from power or must have their initiators mechanically disconnected from potential power sources while being transported or when presented for pre-flight inspection. Such disconnection may be done between the pyrotechnic battery and the device or between the device and any pyrotechnic initiator device(s). Either mechanical switches or complete physical disconnections may be used.

 

[GlueckAuf]

Mr. Shannon,
I hope Tripoli will add the Featherweight Magnetic Switch to the very short list of "approved" remotely-actuated electrical switches soonest. It would be the first non-RF remote switch to earn this approval.

I know my years-long experience with Adrian's extraordinarily compact, simple, secure, economical, and dependable magnetically-actuated switch is only anecdotal evidence, but I am extremely confident with it following countless flights where it has never once malfunctioned. Here's a sample.

Good skies,
GlueckAuf
Tripoli L2

 

[SDramstad]

This thread is more contorted then a constipated boa constrictor. It boils down to this. No energized electronics anywhere in the path to the ejection charges until you are either at the pad or at a designated area. It is no more complicated then that.
Steve

Unless I have misunderstood what has been widely discussed in this thread, I can have energized electronics as long as I have an 'air gap' between the electronics and the charges. So I can continue to use my magnetic or wifi switches exactly as designed, as long as I can break the connection between the electronics and the charge. I even illustrated how I 'twist and tuck' my charge leads, which seemed to be met with approval.

In post 503 Steve seemed to agree with the 'or' of [no power to electronics], or, [no connection to the charges].

So, maybe a bit more complicated than just no energized electronics.


Tony

I meant to take it down to the simplest solution, a single switch on the battery. But disconnecting the charges is a valid way to do this. Once the charge is disconnected there are no energized electronics connected to them.

 

[cerving]

That's what I intend to do with my 38mm MD two-stager with a Quantum on the bottom and a Proton on the top... disconnect the energetics. No room for switches...

 

[mikec]

I hope Tripoli will add the Featherweight Magnetic Switch to the very short list of "approved" remotely-actuated electrical switches soonest.

My suspicion is that the TRA BOD never even thought about the Featherweight products until that question was raised in this thread.

 

[Steve Shannon]

My suspicion is that the TRA BOD never even thought about the Featherweight products until that question was raised in this thread.

No, last summer in a post I explained how the WiFi switch had been submitted but that the magnetic switch had not. Adrian said he’d like to submit it and I asked him to send the submission to me rather than making TRF an official request channel.

But the thing about the Magnetic switch is that it isn’t remote. You still have to be standing right next to the rocket and possibly on a ladder when you arm your electronics. It’s still way better than having to fish in a hole to turn a screw switch while perched on a ladder, though.

Edit to add:
But we really want out of the position of approving individual devices anyway. Our meeting (and there could be more than one) will hopefully result in some best practices and minimum standards for how we switch our avionics on safely. The manufacturers have provided very well prepared position papers and I think it’ll be a very good meeting.

 

[wsume99]

But we really want out of the position of approving individual devices anyway.

This makes complete sense to me. If minimum standards are published then who determines the switch is in compliance with those standards? The vendor self certifies? Some other third party?

 

[jbr]

how is the rso to know that since the altimeter is on, the charges are disconnected?

seems like asking them to have xray vision or clairvoyance

 

[davdue]

how is the rso to know that since the altimeter is on, the charges are disconnected?

seems like asking them to have xray vision or clairvoyance

I thought that at first but if it’s a standard altimeter then it will he beeping out no continuity. If it is a eggtimer WiFi product the web page can show no continuity. If I understand it correctly.

 

[Steve Shannon]

This makes complete sense to me. If minimum standards are published then who determines the switch is in compliance with those standards? The vendor self certifies? Some other third party?

I think you’ll find it will be fairly obvious things, but I would expect vendors to self certify.

 

[Adrian A]

This thread is more contorted then a constipated boa constrictor. It boils down to this. No energized electronics anywhere in the path to the ejection charges until you are either at the pad or at a designated area. It is no more complicated then that.
Steve

Unfortunately, it is more complicated than that, because the rule doesn't just mandate that electronics be powered off until at the pads, it also specifies how that is to be accomplished, and prohibits a method that has been proven safe and reliable for about a decade, while allowing methods that are much less reliable.

 

[Adrian A]

But the thing about the Magnetic switch is that it isn’t remote. You still have to be standing right next to the rocket and possibly on a ladder when you arm your electronics. It’s still way better than having to fish in a hole to turn a screw switch while perched on a ladder, though.

At least one flyer (I forget exactly where I saw this) has put a magnet on the end of a stick that also has a plastic tube running down the length of it. He arms it with the stick magnet and then listens for confirmation using the tube, like a stethoscope.

But the main application for which the 24mm, 29mm and 38mm av-bays were designed is for small, high-performance rockets that are armed while crouching down next to a tower, rather than standing on a ladder. Large rockets have lots of examples for people to follow when wiring up their av-bay. But these parts and techniques don't work in the smallest high-powered rockets. Some ingenuity and creativity is required, which is what attracted me to the hobby in the first place. But more than once I have had a charge go off in my face when working on my own non-standard version of a small av-bay. The Featherweight av-bays provide a safer way for anyone to fly these types of rockets, and if they are effectively banned then I think we'll find that there will be more, not fewer, charges going off behind the flight line. And also more ballistic re-entries. Tony's twist-and-tuck method is the best case I have seen so far for a work-around for using the Featherweight minimum-diameter av-bays, and I believe he has the skill and care to implement it safely. But would anyone seriously argue that making everyone flying a small rocket do that, or design their own av-bay, will make our ranges safer?

 

[mikec]

Yes, the invitations came out this morning, for a meeting sometime next weekend.

Dare I ask if the meeting occurred this past weekend? Is there a timetable for resolution, if any?