rocket trail brings down lightining strike?

rocket trail brings down lightining strike?

Post by Paul Casa » Fri, 29 Nov 1996 04:00:00



Here's one,

Can the smoke trail of a rocket engine cause a lightening strike to
occur? I saw this on the cable channel. They were launching in a sever
storm, using pneumatic tubing instead of wire to initiate the launch.

Think of the rush!  We get one from the engine roar , but this would
be incredible.... (might get the landlord really pissed ) hehehehehe

Paul Casale

 
 
 

rocket trail brings down lightining strike?

Post by brettb.. » Fri, 29 Nov 1996 04:00:00


Quote:
>>>Can the smoke trail of a rocket engine cause a lightening strike to
>>occur? I saw this on the cable channel. They were launching in a sever
>storm, using pneumatic tubing instead of wire to initiate the launch.
>Think of the rush!  We get one from the engine roar , but this would
>be incredible.... (might get the landlord really pissed ) hehehehehe

    I saw that too. They were trailing a thin copper wire, spooling out
like a spinnning reel, that provided the necessary path to get the
lightning to strike.

     If anyone gets the bright idea to try this, you should note that they
were standing in a metal shed (Faraday cage), and used an ignition system
that they blew into to start the engine. They had a plastic tube with some
sort of diaphram at the other end to push the switch remotely. This kept
wire from running from the pad/lightning strike site from being
electrically connected with the launcher.
   This is a pretty dangerous thing to do, and may result in more of a
rush than you wanted. I have been ~100 feet away from a lightning strike
and it was more exciting that you really want.

       I suggest a VCR tuned to TLC is a better way to capture the effect
than actually trying it in person.

       Brett

 
 
 

rocket trail brings down lightining strike?

Post by Bertsch » Fri, 29 Nov 1996 04:00:00




Quote:
> >>>Can the smoke trail of a rocket engine cause a lightening strike to
> >>occur? I saw this on the cable channel. They were launching in a sever
> >storm, using pneumatic tubing instead of wire to initiate the launch.

They also used a device to gather information about the electrical charge
of the cloud. Apparently, you have to launch just seconds before a bolt
comes from the cloud. It took them many, many tries, and even with some
very sophisticated equipment, had a huge failure rate.
Only a complete idiot would try this as an amateur. Even with a wire
leading from the cloud to the launch-pad, there is nothing that says the
lightening bolt can't hit anything on the field, or within a large radius.
You can get this same "rush" joining the many victims who golf during
thunderstorms.
I doubt smoke alone would draw lightening down it, but I don't doubt that
anyone stupid enough to be launching on a clear flat field in a
thunderstorm could avoid being struck for very long. Just don't do it.
Ed
 
 
 

rocket trail brings down lightining strike?

Post by Dave Lyl » Sat, 30 Nov 1996 04:00:00


Quote:

>Here's one,

>Can the smoke trail of a rocket engine cause a lightening strike to
>occur? I saw this on the cable channel. They were launching in a sever
>storm, using pneumatic tubing instead of wire to initiate the launch.

>Think of the rush!  We get one from the engine roar , but this would
>be incredible.... (might get the landlord really pissed ) hehehehehe

>Paul Casale

If this is the same program I remember, I believe they had a wire trailer
connected to the rockets.  The wire formed the initial conductive path,
not the exhaust trail.

Dave

 
 
 

rocket trail brings down lightining strike?

Post by David Newil » Sun, 01 Dec 1996 04:00:00


I have a copy of the article from the early 80's where French weather sccientists were trying this
same experiment. One bolt of lightning DID GO DOWN THE SMOKE TRAIL!  It set off all the other
rockets in the launch rack! Any change in conductance of the air makes a path for the electron
flow. Some propellants use metallic fines to get higher temperature and better burning -- hence a
very nice conductave path.

Just don't do it is a great answer. We  shut down summer launches if therre is lightning visible
for this reason

Dave Newill NAAR 6139  TRA 2034

 
 
 

rocket trail brings down lightining strike?

Post by The Silent Observe » Mon, 02 Dec 1996 04:00:00


<re: rockets into thunderstorms>

Quote:
>    They were measuring the potential gradient of the atmosphere. The
> voltage of the atmosphere has a pretty strong gradient (~100 v/ft) under
> normal conditions and even higher when a thunderstorm is in progress. A
> lightning strike drains the charge and reduces the gradient for a while
> until it charges up again.
>     This effect has been used by a model airplane guy named Maynard Hill
> to run an autopilot for an R/C airplane. I do not know exactly how the
> sensor works but it involves ion sources and some sort of ion sensor to
> make a ultra-high impedence voltmeter. The plans have been published, but
> I am not sure where ( early Model Aviation?). It is not excessively
> complex.
>       Unfortunately for autopilot purposes, sometimes the DIRECTION of the
> gradient changes during thunderstorms, resulting in some interesting and
> undesirable maneuvering.

I remember reading about this system (as I recall, built only as a wing
leveler for high-altitude sailplane flights).  The sensors were foil
patchs near the wingtips, and IIRC, it used a feedback circuit of some
kind to minimize the potential between the wingtips -- though I don't
recall if it was programmed to always lower the wing at higher potential,
or if it was smart enough to reverse itself if the result of a maneuver
was a worsening, instead of an improvement.  That wouldn't be all that
hard to design into a computer-controlled system, but might be a bear to
build with analog circuits.

--
+----------------------------------------------------------------------+
| There are two kinds of fool.  One says, this is old, and therefore   |
| good, and one says, this is new, and therefore better.               |
|                                  John Brunner, _The Shockwave Rider_ |
+----------------------------------------------------------------------+

| Rocket Pages           http://members.aol.com/silntobsvr/modrocs.htm |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of anyone but a rabid libertarian.                         |
+----------------------------------------------------------------------+

 
 
 

rocket trail brings down lightining strike?

Post by brettb.. » Mon, 02 Dec 1996 04:00:00



Quote:
> >>>Can the smoke trail of a rocket engine cause a lightening strike to
> >>occur? I saw this on the cable channel. They were launching in a sever
> >storm, using pneumatic tubing instead of wire to initiate the launch.


Quote:
>>>>They also used a device to gather information about the electrical
charge
>of the cloud. Apparently, you have to launch just seconds before a bolt
>comes from the cloud. It took them many, many tries, and even with some
>very sophisticated equipment, had a huge failure rate.

   They were measuring the potential gradient of the atmosphere. The
voltage of the atmosphere has a pretty strong gradient (~100 v/ft) under
normal conditions and even higher when a thunderstorm is in progress. A
lightning strike drains the charge and reduces the gradient for a while
until it charges up again.
    This effect has been used by a model airplane guy named Maynard Hill
to run an autopilot for an R/C airplane. I do not know exactly how the
sensor works but it involves ion sources and some sort of ion sensor to
make a ultra-high impedence voltmeter. The plans have been published, but
I am not sure where ( early Model Aviation?). It is not excessively
complex.
      Unfortunately for autopilot purposes, sometimes the DIRECTION of the
gradient changes during thunderstorms, resulting in some interesting and
undesirable maneuvering.

Quote:
>Only a complete idiot would try this as an amateur. Even with a wire
>leading from the cloud to the launch-pad, there is nothing that says the
>lightening bolt can't hit anything on the field, or within a large
radius.
>You can get thas a remotely plausible or reliable scientific method of

determining the exact path that lightning will take. You would never get
me to blow into that tube!
     Brett
 
 
 

rocket trail brings down lightining strike?

Post by Jim Yan » Tue, 03 Dec 1996 04:00:00




Quote:



>> >>>Can the smoke trail of a rocket engine cause a lightening strike to
>> >>occur? I saw this on the cable channel. They were launching in a sever
>> >storm, using pneumatic tubing instead of wire to initiate the launch.

>They also used a device to gather information about the electrical charge
>of the cloud. Apparently, you have to launch just seconds before a bolt
>comes from the cloud. It took them many, many tries, and even with some
>very sophisticated equipment, had a huge failure rate.
>Only a complete idiot would try this as an amateur. Even with a wire
>leading from the cloud to the launch-pad, there is nothing that says the
>lightening bolt can't hit anything on the field, or within a large radius.
>You can get this same "rush" joining the many victims who golf during
>thunderstorms.
>I doubt smoke alone would draw lightening down it, but I don't doubt that
>anyone stupid enough to be launching on a clear flat field in a
>thunderstorm could avoid being struck for very long. Just don't do it.
>Ed

NASA has done some research on this,because they experienced strikes from
launching rockets. This led to the development of E-field/H-field detectors to
warn of approaching storms and conditions ripe for lightning strikes. This
also protects the tower crews. Florida has many examples of where people get
struck when storms were not anywhere in sight. Mostly at the golf course or
beach.  
 
 
 

rocket trail brings down lightining strike?

Post by Jason War » Tue, 03 Dec 1996 04:00:00


Quote:

> NASA has done some research on this,because they experienced strikes from
> launching rockets. This led to the development of E-field/H-field detectors to
> warn of approaching storms and conditions ripe for lightning strikes. This
> also protects the tower crews. Florida has many examples of where people get
> struck when storms were not anywhere in sight. Mostly at the golf course or

                              ^^^^^^^^^^^^^^^^^

I have see lightning hit when storms are many miles away. But this
implies
lighting out of a clear sky. You sure about this?  

--
-Jason Ware

---------------------------------------------------------
      VISIT MY ASTROPHOTOGRAPHY HOMEPAGE!!
   ASTRO IMAGES FOR DOWN-LOAD, TIPS, REPRINTS
        URL: http://www.galaxyphoto.com
---------------------------------------------------------

 
 
 

rocket trail brings down lightining strike?

Post by Bertsch » Wed, 04 Dec 1996 04:00:00




Quote:
> I have see lightning hit when storms are many miles away. But this
> implies
> lighting out of a clear sky. You sure about this?  

Here in Tucson, where we get lots of lightning during the monsoons, there
have been several reports of the proverbial "bolt from the blue." Lightning
can and does strike out of a clear blue sky.
It's due either to a very dry climate or a high occurrance of blasphemy. :)
I have never heard of such a thing happening at a launch, however. (Blue
Lightning, that is. Plenty of the other, however.)
Ed
 
 
 

rocket trail brings down lightining strike?

Post by brettb.. » Wed, 04 Dec 1996 04:00:00


Quote:

>>NASA has done some research on this, because they experienced strikes
from
>launching rockets. This led to the development of E-field/H-field
detectors to
>warn of approaching storms and conditions ripe for lightning strikes.
This
>also protects the tower crews.

      They take it VERY seriously. We have all sorts of rules about
lightning during loading and after for Titan IV launches. There are also
very large lightning rods around the pad, even taller than the gantry.
   Needless to say, being around a rocket full of hypergolic propellants
in a lightning strike is a bad place to be....

      Brett

 
 
 

rocket trail brings down lightining strike?

Post by Jim Yan » Wed, 04 Dec 1996 04:00:00



Quote:


>> NASA has done some research on this,because they experienced strikes from
>> launching rockets. This led to the development of E-field/H-field detectors
to
>> warn of approaching storms and conditions ripe for lightning strikes. This
>> also protects the tower crews. Florida has many examples of where people
get
>> struck when storms were not anywhere in sight. Mostly at the golf course or
>                              ^^^^^^^^^^^^^^^^^

>I have see lightning hit when storms are many miles away. But this
>implies
>lighting out of a clear sky. You sure about this?  

>--
>-Jason Ware

>---------------------------------------------------------
>      VISIT MY ASTROPHOTOGRAPHY HOMEPAGE!!
>   ASTRO IMAGES FOR DOWN-LOAD, TIPS, REPRINTS
>        URL: http://www.galaxyphoto.com
>---------------------------------------------------------

Jason,I dont have any reference articles to quote,but I recall reading in the
Orlando Sentinel about people getting struck when the sky was clear. Maybe the
rot has gotten to my mind?? Hope not. :-) After all,a mind is a terrible thing
to waste. One to a customer. By the way,we supposedly have more strikes and
higher current density than anywhere else in the US.
 
 
 

rocket trail brings down lightining strike?

Post by Jason War » Wed, 04 Dec 1996 04:00:00


Quote:

> Here in Tucson, where we get lots of lightning during the monsoons, there
> have been several reports of the proverbial "bolt from the blue." Lightning
> can and does strike out of a clear blue sky.
> It's due either to a very dry climate or a high occurrance of blasphemy. :)

I'm still having a hard time with this. I too have heard reports of
lighting
from a clear sky, however I suspect that many of these reports come from
flashes at night. It turns out a bright meteor can light up the sky and
look like lighting from a dark location. I have been at star parties
where
a bright one flew over. People who were not looking at the part of the
sky where the meteor fell will say "was that lightning?"

Anyway probably the wrong news group for this. With regards to rockets,
lighting studies have been done using rockets that were lauched into
thunderstorms. The rocket trails a thin wire which provides a path
to ground. The operator watches a charge meter, when the static builds
to a high level, the rocket is luanched and KABOOM. Pretty impresive.

--
-Jason Ware

---------------------------------------------------------
      VISIT MY ASTROPHOTOGRAPHY HOMEPAGE!!
   ASTRO IMAGES FOR DOWN-LOAD, TIPS, REPRINTS
        URL: http://www.galaxyphoto.com
---------------------------------------------------------

 
 
 

rocket trail brings down lightining strike?

Post by Neal Bake » Wed, 04 Dec 1996 04:00:00


Quote:

> Here's one,

> Can the smoke trail of a rocket engine cause a lightening strike to
> occur? I saw this on the cable channel. They were launching in a sever
> storm, using pneumatic tubing instead of wire to initiate the launch.

> Think of the rush!  We get one from the engine roar , but this would
> be incredible.... (might get the landlord really pissed ) hehehehehe

> Paul Casale

Actually, they had a small wire tied to the rockets, this was to help
reduce the potential energy difference between the sky and ground just
enough for the lightning to jump. Incidentally, does the lightning jump
down to the ground or up to the sky?

It actually jumps from the ground up...

Check out the Nova tape, it's great!

 
 
 

rocket trail brings down lightining strike?

Post by Bill Nels » Thu, 05 Dec 1996 04:00:00


:
: I'm still having a hard time with this. I too have heard reports of
: lighting
: from a clear sky, however I suspect that many of these reports come from
: flashes at night. It turns out a bright meteor can light up the sky and
: look like lighting from a dark location. I have been at star parties
: where
: a bright one flew over. People who were not looking at the part of the
: sky where the meteor fell will say "was that lightning?"

I have seen such a flash, and examined the damaged pavement in the
middle of downtown that resulted from it.  I was altogether too close
for comfort. And, it happened in midday - without a cloud in the sky.

Why it struck near the middle of the street, instead of one of the buildings
on either side is a mystery to me.

Bill