Wiring Ejection Charges

Well, my first thought would be what could have happened (hypothetically speaking).

Did the rocket not descend to the main alt? 400 or 800 ft power lines? Tree? Radio tower? Mountain. Caught on an airplane or hot air balloon? But I gotta wonder why was the launched in violation of the safety code of hazards in the launch site?

Ok if the rocket reached main alt but did not fire the main? What is it hung up in (tree, powerline, radio tower) and why was it flown in violation of the safety code (hazard in launch site)?

Ok it's there but why didn't it fire? Battery dead? Power leads came loose? Ematch not connected? Bad ematch? Match fired but didn't set off power? Not likely to be an issue.

Ok, it's hung up and the alt is good, primed and ready to fire the charge when the wind blows right.

Who's getting it down? Lineman? He's going to take the time to look all over the rocket to find the little switch and has a small screwdriver handy? Or is he in a hurry to fetch this pain in his rear, yank it off the line and toss it in the bucket.

Cable guy might at least have the right sized screw driver.

When either of them grab the rocket to read that little warning and supposedly disarm the switch, did they just cover the vent hole?

Did you mention what they should do when you called them and paid the huge fine for causing them this pain in the rear?

If the chute wasn't stripped away, it would be a whole lot closer to the launch pad and not in a tree or powerline which wouldn't be in your launch field.

Does anyone have any real situations or do we discuss the possble danger of a static spark when pouring BP from a 1lb can into the ejection canister?

Reply to
Fuzzylogic
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In these days of fear, paranoia, and extremism, the assumption would be to assume that it is an unexploded terrorist bomb. To be safe, use a robot to bring in a pound or so of HE and detonate it. Forensics can sort it out later. :(

Reply to
Alan Jones

On a similar note while stationed at Tuzla Bosnia in '96 a certain female Captain had a "CARE" package sent from a friend in the "States". When the package arrived at Ramstein AB, GE, it was making a buzzing sound. The EOD troops came in made their call and blew the crap out of the package. Contents one activated stress relief device...(vibrator). Cost of said device $20? Shipping $5? look on EOD troops face wnem they realised what it was.....Priceless. Cost to a ceratin Captain....Total Embaressment. It is better to blow up what you do not know than to be blown up by it. IED 101.

Reply to
nitram578

Better than Joe Civilian getting punched in the gut by a nosecone followed with a "BP Face" chaser.

;-)

Reply to
Tweak

So, one of the themes of this thread seems to be that RF doesn't cause ejection charge accidents, user error does, particularly reverse battery errors. So why are we still using flight electronics that fails in a 'fire' mode when this error occurs?

GC

Reply to
Gary Crowell / VCP

Bob mentioned a idea for an altimeter which would safe itself after a time. For some reason it made me consider that while all motor recovery has been certified by an independent organization, none of the electronic recovery is. Specifications and required testing on avionic packages. Now that's starting to sound more like NASA.

Reply to
Fuzzylogic

Sorry, I missed something. What "independent organization" certified motor delays? I thought that was done by TMT, S&T and CAR. Not quite "independent".

And then it's only +/- 20%.

Seems the result of this discussion is that many of the problems were caused, not by the altimeter, but by errors by the flier. Maybe we should certify the fliers! (Oh, wait, I think we do!)

Could be that too many people get certified long before they should...

Hey, Kaplow flies happy meals, and has minimal HP experience. (as does most of the NARBOT, it seems). I still can't understand why he's so vocal in this thread, other than he's just being "kaplow".

Reply to
AZWoody

That's what you get. Fliers with minimal/no HP experience recommending sweeping changes, some of which would serve to increase the risk of inflight failure by adding complexity in order to "child proof" HPR. If you can't wire a battery properly then you have no business flying anything bigger than a happy meal.

I don't get why we want to emulate NASA, either. They can't even convert metric to english.

Unless by emulating NASA they mean spend as much money as possible to make failures that much more painful.

Reply to
Tweak

Nobody mentioned static electricity. I've seen one inadvertant firing after impact that was probably static induced. At a night launch, one flier had his drogue deploy, but not the main. When he picked up the rocket, the main ejection charge fired.

Glen Overby, kc0iyt

Reply to
Glen Overby

Really? I thought most of them were HPR certified.

Reply to
Alex Mericas

What ever gave you that idea? I See Bob on a fairly regular basis at luanches sense 1999. Yes he likes to fly his Estes size creations, but I have seen plenty of HPR out of him.

Reply to
D&JWatkins

Hi Ted, I used to work in law enforcement as an analyst, in the 90s.

Worked the local IT with local agencies like local directed patrol, FBI, customs, IRS Tres agents, our AF friends, DEA etc..

Just what are WMD people ?

CD

Reply to
Cranny Dane

Weapons of Mass Destruction team

Reply to
tedcochran55409

Glen Overby wrote in news: snipped-for-privacy@monolith.nodomain:

What is the reason for thinking this was static electricity induced? Was there a noticeable spark? The rocket would have been lying on the ground and should have discharged any potential it had. The flier should similarly have been slogging about and been at Earth potential.

It seems other scenarios played out earlier in this thread were at least as likely a cause as static electricity.

For example an altimeter that didn't arm or sense properly for deployment, but got a pressure spike by the flier covering or uncovering a vent hole on the ground.

It seems to me that the weak link in all of the unexpected deployment scenarios is the electronics that are fooled into thinking "NOW" is the time. As a microelectronics engineer, I know that chip circuitry is susceptible to electronic noise. The amount of RF or static needed to trip a chip's logic would be a lot less than that needed to fire an e-match. A small transient, applied directly to a chip's sensor inputs, could make the chip believe the sensor was seeing an event.

Similarly, altimeter design that doesn't fail safe when power is transient could trigger the e-match. A design that powers up with a spike on the e- match outputs could set off the charge at arm time.

I'm not saying there are altimeters that do that, I'm just stating that the design of the system whose sole purpose is to light that match, should be the first suspect in any match lighting. Foot scuffing static electricity, or RF interference, directly lighting the match seems less likely than those sources fooling the electronics into doing the job.

ScottE

Reply to
ScottE

Interesting they call it that in today's times.

Which agency out of that list has this team ?

CD

Reply to
Cranny Dane

Ramsey County

Reply to
tedcochran55409

=

Interesting that local directed patrol, or commonly called Metro in the old days, needs a WMD team.

If a real WMD was found in my county, I sure would not want the county sheriff or our metro squad taking care of it ;)

But times do change, perhaps it's the definition of a WMD ?

CD

Reply to
Cranny Dane

The legal definition of "WMD" is incredibly broad (In the US, anyway). It includes everything from hand grenades to spud guns (rifles with barrels larger than 1/2in). It would include many high power rockets, if not for the 'intended for sport use' exception.

I'll see if I can dig up the actual wording.

Reply to
John Bowles

that's the definition of a "destructive device", not a mass destruction ;)

Reply to
Cranny Dane

Thanks John,

I had not seen DD added to the WMD code before.

I wonder how "destructive device" got morphed into WMD ?

Also, some have class three licenses to own DDs like an M240, so now they also own WMDs ?

And Spud guns like you said are now WMDs.....

ok, I'll follow my own advice, follow the money trail.

Funding for preventing WMDs will happen easier then funding for preventing destructive devices.

That also makes the person whose name shall not be mentioned on r.m.r. guilty of brandishing a WMD.....

CD

Reply to
Cranny Dane

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