Black Magic-Another “nominal” minimum diameter N5800 flight

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As interesting as this (Metal vs Composites Round 2, Now With Less Hate) is (and I actually do think it is very interesting), it probably doesn't belong on this thread.

I still want to hear more about how a friggn' N motor was allowed to go off accidentally during the continuity check. Given that my mental image of this event has the team members within spitting distance of their rocket (which is to say tens of feet, which is what I have seen at away cells at other launches), I'm surprised any of them are out of the hospital by now. If I'm ever going to go to NM to fly, I want an explanation of how it happened, what the proximate cause was, and what steps will be taken to prevent it in the future. For such a serious and life-threatening safety breach, is that too much to ask? Or am I taking this too seriously?
 
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I still want to hear more about how a friggn' N motor was allowed to go off accidentally during the continuity check. Given that my mental image of this event has the team members within spitting distance of their rocket (which is to say tens of feet, which is what I have seen at away cells at other launches), I'm surprised any of them are out of the hospital by now. If I'm ever going to go to NM to fly, I want an explanation of how it happened, what the proximate cause was, and what steps will be taken to prevent it in the future. For such a serious and life-threatening safety breach, is that too much to ask? Or am I taking this too seriously?

It was certainly a serious situation, but it was not life-threatening. The wireless controller was supplied by a flyer outside of the club and it was a commercially available unit. After this incident, the manufacturer recalled the launch controller and has discontinued the product.
https://www.rocketiltometer.com/tb002-rockontroller-1-live-output/
https://www.rocketiltometer.com/tb003-temperature-affects-rockontroller-1-external-antenna-versions/
https://www.rocketiltometer.com/tb004-rockontroller-1-discontinued/

The range operations at Tripoli Las Cruces are quite conservative and controlled. The high-altitude (150Kft) pad area is 2.5 miles from the regular HPR launch area. Once a rocket is on the pad and ready to arm, nobody but the flyer and an assistant is allowed at the pad. The LCO location for the high altitude pads is a 1/2 mile back.

The lesson learned is to always assume a launch controlled is hot when powered up and when armed. Test without the igniter in the rocket before cycling it live. Temperature extremes can change the operation of electronics, and RF interference can cause unknown results. Verify the functionality at the launch time and location before connecting to a live igniter.

In the past 23 years doing HPR, I have seen several motor ignitions near the pad. Stuck relays with no built-in alarm feature are the most common. The worst danger is when the person is connecting leads below the motor. In the case we're discussing, the two people at the pad were 30ft away.
 
John, just to clarify a few things ....

I'm the flyer that provided the wireless system. As indicated in the Tech Bulletin 2 that John posted, I screwed up and started up the system incorrectly. The system is supposed to issue a warning but not launch the rocket. The fact that the rocket did launch is the reason that the product has been discontinued. I was able to reproduce this event several times after the launch. However, I have not determined by any means the range of conditions that may cause it. Therefore, i would advise anyone who has this product to carefully review the information on the website and take appropriate action.

Unfortunately, as a result of this incident, the project team didn't get any video or pics of the flight. I certainly regret that, as well as the impact this may have on the vendor involved and of the perception of safety at launch site in New Mexico. On the other hand, it is a good thing that the problem was identified without anyone being injured.

I would also like to clarify that the only person in the immediate area of the rocket was me (about 25 feet plus however many steps I got in before liftoff).

I don't have much else to say about this incident, but if folks want to follow up, please start a new thread. This one should be for the fliers to discuss their flight.

Jim
 
One question: How scary/awesome was it to be 25 feet from an N5800 launch?
 
Thank you, Jim and John, for the clarification and further information.
 
One question: How scary/awesome was it to be 25 feet from an N5800 launch?

Come out to FAR and you'll be about that distance from Q+ liquids, it's an interesting experience :p

Regarding composites versus metals, I would like to add Bandman's recent aluminum bonding tests. He clamped two unsanded pieces of 6061 aluminum together using Loctite Hysol 9430 epoxy, and has yet to tear them apart at over 200+ pounds of force. I am not sure of the exact mechanics of his system, but the epoxy we used for Project60K was, and is, by far the strongest epoxy we have yet come across. As we examined the remains of our project we noted that when the epoxy reached it's glass trans. temperature and peeled from the rocket, it tore layers of nosecone with it.

I would venture to say that our fins, radial base included, could be epoxied directly to a motor tube, and be launched to mach 3+ without incident, so long as production is near flawless.
 
Come out to FAR and you'll be about that distance from Q+ liquids, it's an interesting experience :p

Yes, but there you have a concrete bunker. Jim had no such bunker to protect him from a) potential motor failure, and b) a sky that rains dense rocket parts.
 
Yes, but there you have a concrete bunker. Jim had no such bunker to protect him from a) potential motor failure, and b) a sky that rains dense rocket parts.

hmm, true, but the sound is still pretty freaking intense :p
 
I must say that flight was awesome to see in real life. I really must attempt something like this one day. As for the early ignition that really threw us off by not letting us to be able to record the action. I'm just glad everyone was at least some distance away from the rocket.
 
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