An EX 98mm KABLOOEY!!

[Eat, sleep, and Fly]

Safe distance for an N motor is 1,000 feet. So, your farthest piece went 1/8 of the safe distance.

I'll take that over an N5800 rocket that shredded several thousand feet up, and is coming in ballistic.

-Kevin

The minimum distance is 1000 feet, however they are very rairly launched that close to anybody. All of the launches I have been to, and I have yet to see an N closer then 1500 feet.

 

[DAllen]

I have yet to see an N closer then 1500 feet.

Get yer' tape measure out. I'm going to bet you have - and didn't even know it hahaha.

I know for a FACT not all launch organizers measure out the pad distances...but that's another topic for another thread.

 

[CCotner]

Safe distance for an N motor is 1,000 feet. So, your farthest piece went 1/8 of the safe distance.

I'll take that over an N5800 rocket that shredded several thousand feet up, and is coming in ballistic.

-Kevin

For the record, we will be flying our N5800 half a mile away on a "complex O" away cell, tilted away from the crowd by a few degrees as per AeroPac regulations. We take safety very seriously.

 

[bandman444]

I'll take that over an N5800 rocket that shredded several thousand feet up, and is coming in ballistic.

-Kevin

Ouch Kevin. That hurts.

 

[troj]

Ok yeah, I hadn't really thought it through... but the kinetic energy required to get a small piece of aluminum to travel hundreds of feet and only drop a few feet (before hitting the ground) is pretty big.

But in general, why do they certify reloads that aren't designed to fail in the most safe way possible? Is this another facet of trying to apply professional safety standards to a hobby?

I'm not an expert on the certification process, but my understanding is that the certification bodies do not perform destructive testing. The manufacturers provide some documentation, and that may be where they provide the evidence of failure modes.

Keep in mind that this is a hobby, as well, and unless you want motors to cost you $500 for an H motor, there are limits to where they're going to go, in terms of testing, certification, etc.

You also have to remember that relying on how a material fails for safety isn't the best route. The best route is to make sure people are far enough away so that if it does fail, they're not at risk.

-Kevin

 

[Jeroen_at_CTI]

But in general, why do they certify reloads that aren't designed to fail in the most safe way possible? Is this another facet of trying to apply professional safety standards to a hobby?

Axial failure is an NFPA requirement and our testing body (CAR/MC2) wants to see that demonstrated for a new product line by destructive testing. Not sure if other testing bodies perform this testing.

Jeroen

 

[bobkrech]

NAR S&T also does testing to failure on reload casings as required by NFPA 1125.

Motor casings should be designed fail axially, i.e. spit the nozzle or forward closure, before there is a longitudinal case failure, as the area above and below the rocket has to be clear before launch, minimizing fragments thrown radially from the failed motor.

Bob

 

[SS/EA 6BBL 71 Cuda]

Ouch Kevin. That hurts.

Whoa...:surprised: Brycemeister. I think Kevin WAS referring too MY thunderous shred at Airfest 2012 which was witnessed by the Troj, Manny and, myself at the away cell.oint:

Only seen the video about a hundred times.....

Best quote by an unidentified range crew member was: "We called in the high altitude waiver...FOR THAT?" Nooooooo........:no: I only planned to drive 1500 miles this weekend and, spend a couple of hundred dollars in gas, motel, food....more food....then, sacrifice my newest toy because i wanted to leave a permanent mark on the great state of Kansas.:lol: Now here's your sign.:bangpan:

"Things" do happen....I've seen the safety standards work very well to date, but we ALWAYS have to be on the lookout for the unexpected to happen....

I've seen more damage caused by Estes rockets and, "small" high power rockets....than anything else (Even my trusty rusty rocket retriever got 'tagged' at out Sunday launch last week.....yellow paint residue.) At least with the bigger stuff i can usually see the parts/hear the sound but, even then THAT whistle is a very EERIE sound.

Last year when i had a tour of CTI's facilities in Gormley....Jeroen took me out to the test cells and, pointed out more than a few dings and, dents in the test fixtures (with kind of a smile too!):smile:

The BEST EX'rs and, most of our commercial propellant manufactures make it look too easy....they do the homework and, we do the rest...hopefully in a safe/fun way.....It's our responsibility to do so.

1. *smooth* Things over with Bryce? *smooth* *smooth*-Check!
2. Make Kevin look innocent....Check!
3. Get FREE 150mm 40k hardware from CTI!:smile:......*fizzle*

Keep "tweaking" on that O3400 Jeroen until you are absolutely *happy* with it!

I've got some unfinished business to attend to in Kansas later this year!

 

[AlphaHybrids]

I thought the accepted wisdom in hobby rocketry was to design motor cases that failed in closure retention significantly before the tube failed, to keep spectators safe...I'm less interested in going to TRA research launches, now...I value my life!

I have seen more commercial motor failures than research ones. And, like Kevin, rocket recovery issues cause me much more concern.

Edward

 

[CarVac]

I have seen more commercial motor failures than research ones. And, like Kevin, rocket recovery issues cause me much more concern.

Edward

At the same time, most users of commercial motors are less trained than ex'rs. As far as my school's experience goes, 95 percent of Aerotech failures are due to misassembly.

That said, do you have a photo of that case wrapped around the launch rod?

 

[troj]

Whoa...:surprised: Brycemeister. I think Kevin WAS referring too MY thunderous shred at Airfest 2012 which was witnessed by the Troj, Manny and, myself at the away cell.

Actually, my point was that the poster was expressing concern about a CATO that generated zero risk to anyone at the launch, while at the same time planning a launch of an N5800 minimum diameter rocket, which, statistically speaking for such rockets, is much more likely to generate risk for attendees.

-Kevin

 

[Nerull]

The most afraid I've ever been at a launch was multiple simultaneous M/N powered Gizmo XLs core sampling around the spectator area from above the cloud deck, with no warning but a terrifying wail until just before impact. One of the most glaring examples of "go fever" I've ever witnessed.

On-the-pad CATOs don't even register.

 

[dixontj93060]

The most afraid I've ever been at a launch was multiple simultaneous M/N powered Gizmo XLs core sampling around the spectator area from above the cloud deck, with no warning but a terrifying wail until just before impact. One of the most glaring examples of "go fever" I've ever witnessed.

On-the-pad CATOs don't even register.

Uhhh, was this MWPX... I was frightened too... I cannot believe the number of rockets that "mis-performed" in that drag race--JEEZ!

First most scary event:

[video=youtube_share;aw3gGPtaA1o]https://youtu.be/aw3gGPtaA1o[/video]

Second most scary event (MWP9):

[video=youtube_share;-LmbTicdmr4]https://youtu.be/-LmbTicdmr4[/video]

Third most scary event (lawn dart of an L3 rocket at MWPV--can't find that video).... but here's the rocket:

 

[troj]

The most afraid I've ever been at a launch was multiple simultaneous M/N powered Gizmo XLs core sampling around the spectator area from above the cloud deck, with no warning but a terrifying wail until just before impact. One of the most glaring examples of "go fever" I've ever witnessed.

Ballistic rockets bother me (and yes, I've had some), but rockets above the clouds bother me even more. 'tis a major No-No!

-Kevin

 

[WILDMANRS]

The most afraid I've ever been at a launch was multiple simultaneous M/N powered Gizmo XLs core sampling around the spectator area from above the cloud deck, with no warning but a terrifying wail until just before impact. One of the most glaring examples of "go fever" I've ever witnessed.

On-the-pad CATOs don't even register.

Really "Go fever" we held the launch of the Gizmo's for the cloud ceiling, so they didn't go into the clouds.
One lawn darted well behind the spectator area and one darted way out on the range.

 

[WILDMANRS]

Uhhh, was this MWPX... I was frightened too... I cannot believe the number of rockets that "mis-performed" in that drag race--JEEZ!

First most scary event:

[video=youtube_share;aw3gGPtaA1o]https://youtu.be/aw3gGPtaA1o[/video]

Second most scary event (MWP9):

[video=youtube_share;-LmbTicdmr4]https://youtu.be/-LmbTicdmr4[/video]

Third most scary event (lawn dart of an L3 rocket at MWPV--can't find that video).... but here's the rocket:

View attachment 118811

Was that the launch of the bleeding edge that was on of the most scary rockets I have ever launched?

 

[troj]

Really "Go fever" we held the launch of the Gizmo's for the cloud ceiling, so they didn't go into the clouds.

Good to hear -- going into the clouds = Very Bad.

-Kevin

 

[WILDMANRS]

Scary things happen at HIGH POWER ROCKET launches.
I travel all over the country to rocket launches and I can not remember the last large launch I went to that didn't have a 4" or better lawn dart .
Some of the notable ones are last year at LDRS a giant V2 i believe lawn darted into the parking area, the N drag race Airfest that the motor case came down in between 2 cars with a women sitting in one of the cars. and last year when a short fat rocket lawn darted into the the staging lanes just missing a kid waiting in line at airfest.
or when the Estes rocket went through Darryl's trailer in between Jim and Darryl's heads at Thunderstruck

If you think MWP is to scarey for you than maybe you shouldn't be at a HIGH POWER ROCKET launch

 

[DAllen]

Actually what I find REALLY scary are launches that don't follow the rules - especially NFPA 1127 or the terms of their waiver. If there were ever an incident at one of those launches that aren't following the rules (heaven forbid) we can kiss our insurance bye bye and watch the lawyers open a can of whoop-a$$ the likes of which we have never seen. And then have some alphabet government agency step in and regulate our little hobby out of existence all in the name of public safety.

But that's not something we don't have to worry about because everyone here is following the rules...:wink:

 

[daveyfire]

Actually what I find REALLY scary are launches that don't follow the rules - especially NFPA 1127 or the terms of their waiver. If there were ever an incident at one of those launches that aren't following the rules (heaven forbid) we can kiss our insurance bye bye and watch the lawyers open a can of whoop-a$$ the likes of which we have never seen. And then have some alphabet government agency step in and regulate our little hobby out of existence all in the name of public safety.

But that's not something we don't have to worry about because everyone here is following the rules...:wink:

It's nice flying in states that haven't adopted 1127 as law :wink:

 

[GRIFFIN]

This thread was more fun when we just talking about Manny's failed motor. Why does EVERY thread, having some topic remotely related to a "DANGER", quickly turns into "who can talk about the most dangerous thing I ever saw at a launch"


I don't think it does ANY of us good if we "Highlight" the things that we thought were dangerous. If anyone is in this hobby and thinks they are not involved in a "dangerous hobby" needs to buy a train set. I agree that rules need to be followed. If every rule was followed 100% of the time at 100% of the launches, there would still be "dangers"

Reckless and dangerous are two different things. I don't care if anyone says that the events at a launch are "dangerous" I would take it personally if I were called "Reckless". I have seen many dangerous flights from seasoned veterans to newbees, vendors to manufactures....face the facts here, this IS a dangerous hobby. We should all be aware of that and ask ourselves...."what is the point I am trying to make" (before posting a bunch of videos about what they considered to be dangerous).

 

[DAllen]

This thread was more fun when we just talking about Manny's failed motor. Why does EVERY thread, having some topic remotely related to a "DANGER", quickly turns into "who can talk about the most dangerous thing I ever saw at a launch"


I don't think it does ANY of us good if we "Highlight" the things that we thought were dangerous. If anyone is in this hobby and thinks they are not involved in a "dangerous hobby" needs to buy a train set. I agree that rules need to be followed. If every rule was followed 100% of the time at 100% of the launches, there would still be "dangers"

Reckless and dangerous are two different things. I don't care if anyone says that the events at a launch are "dangerous" I would take it personally if I were called "Reckless". I have seen many dangerous flights from seasoned veterans to newbees, vendors to manufactures....face the facts here, this IS a dangerous hobby. We should all be aware of that and ask ourselves...."what is the point I am trying to make" (before posting a bunch of videos about what they considered to be dangerous).

Because we're a bunch of drama queens to one degree or another. Seriously - and if you say you aren't you're lying. It's a silly game of unneeded oneup-manship. It's something to do with how we humans are wired and I suspect it's not just rocketry either. Look at what's popular on TV for crying out loud. Look at what stories lead the news programs or are on the front page...Not justifying it - just an observation.

 

[mannyskid]

Jason, I couldn't agree with you more. I would rather laugh at a bunch of you guys making fun of me than to read posts blaming me and other rocketeers for being "reckless" or "unsafe". Now please, this thread doesn't need to be do serious GAWD

 

[GRIFFIN]

Because we're a bunch of drama queens to one degree or another. Seriously - and if you say you aren't you're lying. It's a silly game of unneeded oneup-manship. It's something to do with how we humans are wired and I suspect it's not just rocketry either. Look at what's popular on TV for crying out loud. Look at what stories lead the news programs or are on the front page...Not justifying it - just an observation.

I don't disagree. I just don't understand the point of talking about these things so much. If you were having a conversation with your car insurance agent, would you constantly talk to him about how much you speed and break the laws?

 

[CCotner]

Scary things happen at HIGH POWER ROCKET launches.

Well, that settles it. If that's the attitude by which blatant and intentional violations of the safety code are defended, creating situations by far more dangerous than anything I've seen at AeroPac/ROC launches, I'm never going to midwest power anything. You guys aren't even trying to be safe-it's almost like you're trying to make the launch more dangerous and therefore 'exciting'...

Danger isn't the point of the hobby. If you're going to intentionally make unsafe launch decisions and put unsafe vehicles at unsafe distances, I'm out. I know my opinion doesn't count for much, but when no attempt is made to follow the letter or the spirit of the law (1127), it's not a hobby anymore, it's just illegal activity.

And re: Manny; if we don't collectively take safety seriously, people are going to get hurt. Tripoli can only afford to hush-up so many major injury lawsuits every year...mainstream media attention to major injuries or fatalities in this hobby will be the end of it, forever. There isn't anything more serious in this forum.

Edit: I use the word dangerous, but upon more careful reading of the above discussion, perhaps "reckless" is a more appropriate term. Ignoring legal restrictions is "reckless". Launching unstable vehicles at unsafe distances is "reckless".

Edit 2: Re: wildmanrs; I don't know what definition you use for "going into the clouds", but for me, I like to say that a rocket has gone into the clouds when it is no longer visible when it is at an altitude where it should easily be visible; such as is illustrated in the video from MPX posted here.

 

[Yoehahn]

If you are as safe as possible, things can still go wrong. MY friend has a fake eye because hers got severely injured when a bottle cap flew off of a glass bottle of coke and hit her in the eye. I Have had deployment charges blow on me, Motors CATO and rockets Lawn Dart. I double check everything I do and Im as safe as I can be in the hobby, But things will inevitably go wrong. No one likes it, but it will happen. The best thing you can do is take as many precautions as possible and hope for the best. WE are playing with advanced materials, Fire, Explosives, High speeds and the defiance of gravity. At the end of the day, its not entirely safe no but if you are smart about it no one should ever be injured.

 

[DAllen]

I don't disagree. I just don't understand the point of talking about these things so much. If you were having a conversation with your car insurance agent, would you constantly talk to him about how much you speed and break the laws?

Nope sure wouldn't. Now my buddies over a few brews? Yeah, probably.

 

[CCotner]

If you are as safe as possible, things can still go wrong. MY friend has a fake eye because hers got severely injured when a bottle cap flew off of a glass bottle of coke and hit her in the eye. I Have had deployment charges blow on me, Motors CATO and rockets Lawn Dart. I double check everything I do and Im as safe as I can be in the hobby, But things will inevitably go wrong. No one likes it, but it will happen. The best thing you can do is take as many precautions as possible and hope for the best. WE are playing with advanced materials, Fire, Explosives, High speeds and the defiance of gravity. At the end of the day, its not entirely safe no but if you are smart about it no one should ever be injured.

My problem is with the people who aren't trying to be smart about it, and are intentionally not taking precautions.

 

[CCotner]

I know for a FACT not all launch organizers measure out the pad distances...but that's another topic for another thread.

...like this.

 

[CarVac]

Just curious: How many of the Gizmos that didn't recover properly had been flown before the mass drag race?