Safety Incident from NSL:

[cwbullet]

For those who are TRA members:

The Triploi Report has an article that occurred in Colorado uring NSL. I strongly recommend you read Bob Brown's article entitled "It's only a J". It might give you a little insight and clarity on the event and a few things you should and should not do in camp or a hotel.

It is in the September issue of the TRIPOLI REPORT.

 

[cwbullet]

I have opened the thread for comments.

 

[3stoogesrocketry]

Can you post a copy or direct link to the report please Chuck?

 

[tsmith1315]

https://www.tripoli.org/content.aspx?page_id=22&club_id=795696&module_id=500934

 

[ONAWHIM]

This was really bad with the potential to be much worse.


Tripoli.org > Member Svcs > HPR Magazine
(I too stumbled a bit)

 

[David Schwantz]

I had a J800T go off in my face last year. it was vertical, on the rail with alt's armed. I was able to get out of the blast zone, was not hurt. It was determined that a failure of the launch equipment had caused the ignition. This was on an away cell, a new rule was implemented that one lead from the launch relay must be disconnected before installing ignitor. At least this way you are several feet from the rocket, and not underneath it, as I was, if something were to light.

 

[cwbullet]

I had a J800T go off in my face last year. it was vertical, on the rail with alt's armed. I was able to get out of the blast zone, was not hurt. It was determined that a failure of the launch equipment had caused the ignition. This was on an away cell, a new rule was implemented that one lead from the launch relay must be disconnected before installing ignitor. At least this way you are several feet from the rocket, and not underneath it, as I was, if something were to light.

What kind of launch system?

 

[David Schwantz]

Hi Chuck, it is one that was made by one of our members. Figured that a relay got stuck in the closed position. I had an ignitor fail, went out to replace it, as soon as I hooked up the second lead, she went off.

 

[tfish]

Hi Chuck, it is one that was made by one of our members. Figured that a relay got stuck in the closed position. I had an ignitor fail, went out to replace it, as soon as I hooked up the second lead, she went off.

a good practice is to always ..strike the 2 leads from the controrller together... looking listening for a spark..

and when you do connect that last lead to the igniter..have a quick way out..

Tony

 

[David Schwantz]

Hi Tony, I did. No spark. Might have hit a dirty spot on clip or something. That is one of my routine things.

it was on the grain bin, the leads have to come down through the aluminum leg work. I was under it

 

[tsmith1315]

Hi Tony, I did. No spark. Might have hit a dirty spot on clip or something. That is one of my routine things.

That's good to know, I won't trust it in the future.

 

[SolarYellow]

Would it be a good idea to use a test light or volt meter between the leads?

 

[cerving]

It was not an Eggtimer altimeter that was involved, however we have added a safety notice to all of the altimeter download pages on our web site advising users not to attempt to update their altimeter with a pyro load connected. We'll update our docs too. What seems like common sense to some of us may not be for those who may not be totally familiar with their electronics yet.

 

[bad_idea]

It was not an Eggtimer altimeter that was involved, however we have added a safety notice to all of the altimeter download pages on our web site advising users not to attempt to update their altimeter with a pyro load connected. We'll update our docs too. What seems like common sense to some of us may not be for those who may not be totally familiar with their electronics yet.

Well done, Cris. Incidents like this build the collective wisdom of the hobby, but in time individual scares get forgotten unless they become part of the institutional memory. Eggtimer documentation is part of that institutional memory.

 

[rocket_troy]

Would it be a good idea to use a test light or volt meter between the leads?

Volt meter might not be a reliable indicator. Some cell boxes (I think) provide a (high impedance) voltage even when not triggered/active - albeit a lower voltage than an active output. I discovered that this very weekend with a Wilson unit when testing the wires for an LED indicator I needed for an ignition delay recording. A measurable difference in voltage, but something still susceptible to misinterpretation. In fact, from memory, there was enough power going through the LED to illuminate it quite noticeably in broad daylight when the output wasn't active.

How about an audible or visual indicator from the cell box that indicates that a pad is "live". Shouldn't be difficult to implement? An old 12W automotive incandescent lamp should be a reliable indicator as a "test light" though.

TP

 

[Sooner Boomer]

We've got a knife switch attached to the battery that powers the away pad. When you approach the pad to put a rocket on a rail (or rod), the first thing you do is to open the switch. With a nice big knife switch, there's no doubt as to whether the pad is powered or not. After the igniter is installed and clips are attached, only then is the switch closed. If a relay is stuck and the motor ignites accidentally, at least you're 15 feet or so from the pad.

 

[OzHybrid]

So what were the electronics involved and WHY did it fire. What can be done to prevent this in the future? (Not obviously taking a loaded rocket into a hotel room, or failing to remove the igniter from the motor, or having loaded ejection charges, or the bad judgment.)

The thing that actually caused the incident was electricity in the wrong place. Everything else was a compounding factor.

What exactly caused that? What electronics? What battery? What switch? That's what needs to be revealed. Have any other close calls happened with the same electronics.

 

[cwbullet]

So what were the electronics involved and WHY did it fire. What can be done to prevent this in the future? (Not obviously taking a loaded rocket into a hotel room, or failing to remove the igniter from the motor, or having loaded ejection charges, or the bad judgment.)

The thing that actually caused the incident was electricity in the wrong place. Everything else was a compounding factor.

What exactly caused that? What electronics? What battery? What switch? That's what needs to be revealed. Have any other close calls happened with the same electronics.

Hopefully this will be released eventually.

 

[bschultz32]

Rocket_Troy said "How about an audible or visual indicator from the cell box that indicates that a pad is live?". Michigan Team-1 uses the Altus Metrum TeleLaunch system, and that's exactly what it does. The TeleFire unit at the pads has a Safe/Arm switch. The switch is in the Safe position while rockets are prepared for flight. One of the last things you do before leaving the pad is change the switch position to Arm, and a loud clicking noise starts. When I move that switch to Arm, I always face AWAY from the rocket, because while a burnt back is bad, a charbroiled face is very, very bad. Remember that a motor takes a second or two to come up to pressure; that's precious time to sense something is wrong and start moving away.
When you hook up the igniter clips, focus and listen.
When you arm the TeleFire, focus and listen.
These things are second nature to Olde Dawgs, but this hobby has a constant influx of new people who need to be taught.

 

[Buckeye]

I am not Tripoli, so I can't read the article. Is Tripoli revealing details about the incident at the NAR event, while NAR says they are still investigating and reluctant to say more (as of June 2023)? That would be odd.

Since we are talking launcher safety, here is a schematic showing an audible alarm (PZ3) if the relay is stuck in the closed position, an indication to not arm the pad. I implemented this in my homebrew wireless launcher.

 

[Antares JS]

Is Tripoli revealing details about the incident at the NAR event, while NAR says they are still investigating and reluctant to say more (as of June 2023)? That would be odd.

Not sure what NAR says, but the gist of the article is that a two stage rocket had an igniter in the sustainer, the flyer decided to update his altimeter's software in a hotel room without disconnecting everything, and the sustainer igniter was set off and the motor burned and wrecked the room.

 

[jmasterj]

Are there any consequences from Tripoli for the perpetrator? There were so many failures to follow the safety code getting to the final result, it boggles the mind. This unnamed guy could easily cost all Tripoli members whenever the insurance gets renewed, even if his actions clearly weren't covered by it.

 

[Buckeye]

Not sure what NAR says,

https://www.nar.org/message-from-the-president/
Scroll down to "Message from the NAR President (June 2023)"

 

[Antares JS]

Does the are there any consequences from Tripoli for the perpetrator? There were so many failures to follow the safety code getting to the final result, it boggles the mind. This unnamed guy could easily cost all Tripoli members whenever the insurance gets renewed, even if his actions clearly weren't covered by it.

Offhand, I would think the repair bill from the hotel would be enough punishment. Probably a lot of rockets he won't be able to afford. Like you said, this isn't covered by insurance since he violated the safety code.

 

[Tractionengines]

These things are second nature to Olde Dawgs...

Not having an issue or close call leads to "going thru the motions" without fully paying attention.

I think its a bell curve.
New people are learning and may miss something, due to inexperience. Then, experienced people with check sheets, taking time step-by-step, with caution. Then "Olde Dawgs" who can allow complacency sneak in, if not careful.

 

[Philip Tiberius D.]

We've got a knife switch attached to the battery that powers the away pad. When you approach the pad to put a rocket on a rail (or rod), the first thing you do is to open the switch. With a nice big knife switch, there's no doubt as to whether the pad is powered or not. After the igniter is installed and clips are attached, only then is the switch closed. If a relay is stuck and the motor ignites accidentally, at least you're 15 feet or so from the pad.

 

[Rob Campbell]

As bad as this situation was, it could have been a lot worse. Nobody was burned and the fire was put out. The big take away from this is follow the safety code.

 

[cwbullet]

I have thought about this event and some of the practices I have seen.

I am leary about hooking anything an altimeter prior to arriving on the field. There are plenty that hook up charges, but I do not thing it is a good idea. It only take a small jolt and a short -> Poof you have accident. I have seen too many wired break or come loose.

 

[bad_idea]

Not sure what NAR says, but the gist of the article is that a two stage rocket had an igniter in the sustainer, the flyer decided to update his altimeter's software in a hotel room without disconnecting everything, and the sustainer igniter was set off and the motor burned and wrecked the room.

The odd thing is, this being a NAR launch, there shouldn't have been any kind of HEI, so the starter should have been easy to remove even if it had been inserted on the pad.

Does the are there any consequences from Tripoli for the perpetrator? There were so many failures to follow the safety code getting to the final result, it boggles the mind. This unnamed guy could easily cost all Tripoli members whenever the insurance gets renewed, even if his actions clearly weren't covered by it.

Paying to rebuild a hotel room has got to be a punishingly hefty expense. Potentially bankrupting to many folk unprepared for emergency expenses, though probably not to a senior rocketeer with a travel budget. Flyer is lucky the hotel didn't burn down. Very few people could afford that without insurance, even if there were no injuries.

 

[mikec]

So what were the electronics involved and WHY did it fire.

Firing during a firmware update is obviously a lot more forgivable than firing under more normal conditions (like at power-on), but it does make one wonder if the firing circuits were as robustly designed as they could have been. I doubt there is guaranteed I/O behavior during firmware update for all microcontrollers.