Rocketry Related Thread

Amen.

To be a "Model Rocket" it must meet the legal definition.

This includes CA law and regulations.

It will thus fall upon the "hobby rocket community" to educate both the public and the media. Good luck with that!

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That's where we should stop and think really hard. Yes, all opportunities to show a proper, safe launch and calculations, simulation, and precautions should be emphasized. Should we go around referencing the rocket that killed a guy? I would say no. Even if we have proof it was an ill-advised, unsafe launch, the overall effect would seem to be negative.

I am pretty well known (by like a hundred people or so) in scout, church, and school as a "rocket guy." Not one person has said boo about this story. So just from my personal experience, I'd say the Flying X wing rocket with thousands of observers and media coverage and stories, was a bigger black eye for rocketry in general. I understand the vast difference in outcomes from the actual events, and I acknowledge that it may be different in California where this happened. But people asked me about that stupid X wing and how people with so much building and launching expertise could "screw the pooch" so badly. I was asked about it multiple times. So there's that.

For those of you who are not NAR members......

See this excellent email/letter sent out to NAR members from Ted Cochran:

National Association of Rocketry

21 November 2015
Greetings,
As I reported on the NAR Facebook page last Sunday, I regret to have to inform you that a fatal on-field rocketry accident occurred in California last Saturday. I want to bring you up to speed on the status of our investigation.

When I made the first announcement, there were few details available. We have since been working to understand what happened, so that we may all learn from it and prevent it from happening again. Our Association has no standing in the matter except as concerned and experienced enthusiasts, but I've been in contact with law enforcement and witnesses and have a preliminary set of facts to share.

First, to the best of our knowledge, no NAR or TRA members were involved in this incident, certainly not directly involved. No kids were involved, except, unfortunately, as witnesses.

The deceased, Mike Bentley, a very experienced adult Scout leader, was at an annual BSA Council-sponsored rocketry and camping event for multiple scout troops called Rocket Rave, which has been conducted for at least several years. During the weekend, scouts complete tasks required for their Space Exploration merit badge, which requires two model rocket launches. During the launches, it has also been common for adults to launch their own, larger rockets.

Around noon on Saturday, Mike engaged in a drag race with a second adult. Winds were likely within limits, safe distances were at least close to being met, and both rockets probably met the weight and power limits defined by the NAR Model Rocket Safety Code. The drag race was conducted from a dedicated area, to one side of the primary launch pads for the scouts to use to fly their conventional A through C powered model rockets, and about two dozen people were in the immediate vicinity.

Mike's rocket was powered by a small APCP motor; the other rocket was powered by at least one, and possibly more, black powder motors. Both rockets launched; while Mike was watching his rocket, the other rocket arced over and came down ballistically, striking him in the face and causing severe injuries. Despite the best efforts of scouts, law enforcement, and medical professionals both at the scene and afterwards, his injuries were ultimately fatal.

We know that the rocket that struck Mike was about four feet long and four inches in diameter. It had a cardboard body tube and a plastic nose cone. We don't know much else for sure. It is possible that the rocket was designed to fly on a cluster of motors, but at least one picture of the flight does not clearly show more than one motor firing. No parachute was deployed; none was seen at the accident site. At least one report indicates the rocket was damaged prior to flight. We don't know what motor(s) were used and whether they all ignited and functioned as designed. We don't know if applicable local laws were fully observed.

I do know that the investigating law enforcement authority is not pursuing a criminal investigation at this time. The lack of an investigation will likely leave questions unanswered for some time. We don't know if the rocket would have been allowed to fly at a NAR launch; we can't definitively say whether the NAR safety code was observed or not. We will continue to gather information to the best of our ability, and we'll pass on significant new findings to you.

Where does this leave us? We know that rocketry remains orders of magnitude more safe than any other outdoor activity we can name, provided the safety codes are followed. But it is not without risks; the safety code is our primary means of mitigating those risks.

Everything in the safety codes is there for a reason, and I urge you to continue to observe-and when prudent, exceed-their recommendations every time you fly.

Do preflight inspections of every rocket. Be especially careful with complex rockets. Pay special attention to the recovery system.

Tilt your launch guides away from the crowds: Plan to have good flights, but also plan for bad flights to end in safe places.
Add to the safe distance standards when lots of observers are present.
Make sure launch controllers and ignition methods are appropriate for the motor(s) being used.
Have a spotter for every rocket in a drag race, near enough to the RSO to be able to get a warning out if necessary.
Have people point at malfunctioning rockets if they see them.
Make sure the crowd can hear the RSO.
Confirm the stability of untested designs.
If rockets are flying over spectators, stop and fix the problem.
Offer to help people and groups who are just starting down the path that we have trod. Set a safe, positive, and helpful example.
Please consider contributing to Mike's memorial fund through his gofundme site.

I'll continue to keep you informed, so that we can learn what we can from this unfortunate accident, and be safer because of it.
Sincerely,
Ted Cochran
President, National Association of Rocketry

Thanks for the update, S6.

I read Ted's email and sent him a thank you for sending it out. I'm glad that they are trying to gather the best information they can even though it was not a NAR event.

o1d_dude said:

Thanks for the update, S6.

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+ one

Glad to hear from the Prez

I'll tip my hat to that.

Glad to hear more from Ted Cochran.

I for one am surprised that a rocket made from cardboard and plastic powered by a black powder motor can do so much damage. Unfortunately it was a matter of "just the right (wrong) time and place" for Mr. Bentley. Certainly tragic. But it behooves us all, as they say, to "re-double our efforts" with regards to safety measures at our launches.

dixontj93060 said:

Glad to hear more from Ted Cochran.

I for one am surprised that a rocket made from cardboard and plastic powered by a black powder motor can do so much damage. Unfortunately it was a matter of "just the right (wrong) time and place" for Mr. Bentley. Certainly tragic. But it behooves us all, as they say, to "re-double our efforts" with regards to safety measures at our launches.

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Huh? 4" pointy object weighing a pound or more came in at terminal velocity (or close to it) and impaled the guy in the face. The result is not surprising at all.

Agreed on re-doubling our efforts. As mentioned before, drag races and night launches (events where it is hard to see everything) need the most scrutiny.

Buckeye said:

Huh? 4" pointy object weighing a pound or more came in at terminal velocity (or close to it) and impaled the guy in the face. The result is not surprising at all.

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Actually, no, not necessarily obvious. I haven't studied the physics, but it is possible to design crumple structures that absorb and dissipate the force--look and Indy cars. When a cardboard rocket airframe impacts, either through splitting or an accordion effect, there is some force dissipation. Obviously not enough in this case and/or the impact area was soft enough that nothing would have helped.

Buckeye said:

Huh? 4" pointy object weighing a pound or more came in at terminal velocity (or close to it) and impaled the guy in the face. The result is not surprising at all.

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I feel the same way. After seeing paper make holes in windows, windows and floorboards, sheet metal, etc

rstaff3 said:

I feel the same way. After seeing paper make holes in windows, windows and floorboards, sheet metal, etc

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I've seen that damage with fiberglass, just never personally seen it with paper/cardboard. But for sure, I'm sufficiently on alert now!

dixontj93060 said:

I've seen that damage with fiberglass, just never personally seen it with paper/cardboard. But for sure, I'm sufficiently on alert now!

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Seen as in photographic evidence through the years and possibly the attached commentary, sorry to mislead.

Human error. It is always present in one form or another. And it has happened to all of us at one time or another, myself included.

https://www.rocketryforum.com/showthread.php?24999-Lawn-Dart-Core-Sample-Gallery

[video=youtube;Nj-fFDJ04Ic]https://www.youtube.com/watch?v=Nj-fFDJ04Ic[/video]

tmacklin said:

Human error. It is always present in one form or another. And it has happened to all of us at one time or another, myself included.

[video=youtube;Nj-fFDJ04Ic]https://www.youtube.com/watch?v=Nj-fFDJ04Ic[/video]

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Rocket aimed towards houses. Really!?!??!?

Buckeye said:

Rocket aimed towards houses. Really!?!??!?

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No, but I have experienced failures of recovery devices from various causes at various times. How about you?

dixontj93060 said:

Actually, no, not necessarily obvious. I haven't studied the physics, but it is possible to design crumple structures that absorb and dissipate the force--look and Indy cars. When a cardboard rocket airframe impacts, either through splitting or an accordion effect, there is some force dissipation. Obviously not enough in this case and/or the impact area was soft enough that nothing would have helped.

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While it is true that a lot of energy can be dissipated there is still a lot of damage at the point of impact.

dixontj93060 said:

Actually, no, not necessarily obvious. I haven't studied the physics, but it is possible to design crumple structures that absorb and dissipate the force--look and Indy cars. When a cardboard rocket airframe impacts, either through splitting or an accordion effect, there is some force dissipation. Obviously not enough in this case and/or the impact area was soft enough that nothing would have helped.

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The impact energy and forces need to be dissipated somewhere. Crumple structures are designed to protect the occupants inside a vehicle from experiencing excessive deceleration forces. The forces are dissipated within the crumple zone which is sacrificed and destroyed in the process.

The NASCAR SAFER Barrier is a rigid exterior wall that crushes a series of polystyrene closed cell foam plates mounted on a conventional concrete barrier wall. The plate crushing reduces the peak force of the impact transferred to the occupant of the vehicle by allowing the wall to move. This is the same concept used for bullet proof vests and body armor. Unfortunately the human body is weaker than the structure of rocket and is mass that absorbs the kinetic energy of a rocket impact.

https://en.wikipedia.org/wiki/SAFER_barrier

Bob

We are now more than 3 years past this tragedy. Are photo's of the rocket in question available ?

Dave F.

Ez2cDave said:

We are now more than 3 years past this tragedy. Are photo's of the rocket in question available ?

Dave F.

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I’ve never seen anything beyond Ted’s post.