In article , Leo
writes:

On Mon, 15 Nov 2004 21:24:23 -0500, Mike Coslo
wrote:

Leo wrote:

On Mon, 15 Nov 2004 19:50:46 -0500, Mike Coslo
wrote:


Len Over 21 wrote:



It's times like this that can bring people together. You and Brian
Kelly have something in common.


Realism?

Perhaps you could tell me, Leo? I've shown that it can and does happen
and that a lot of people are doing exactly what I speak of on a regular
basis. Believe or don't believe. It is your choice.

Mike, my point was that you have two folks with a fair amount of
knowledge and experience taking the time to give you feedback. They
aren't saying that you're nuts to be considering doing what you intend
to do, but they are offering you the benefit of their understanding of
engineering and physics as it pertains to your project.

If they are missing something (and me too, perhaps - this sure ain't
my area of expertise either!), then by all means show them where
they're wrong - but they are both pretty intelligent, educated and
knowledgeable guys, with years of real-world experience in their
fields - maybe worth at least a rational discussion? Or you could
throw a bunch of web references in their faces and get angry....

Your call.

Sigh...there will be NO "rational discussions" in THIS newsgrope
by PCTA with any NCTA. Hasn't been before, won't be ever until
the last code key is pried from cold, dead fingers. :-)

There have been - literally - millions of balloons lofted carrying
radio transmitters to high altitudes. Very, very few of those made
it past 50 kilofeet altitude...they weren't designed to do that and
part of that design-for-meteorology-by-metrology used ground-
level helium-filled closed balloons.

Basic information needed for any "manager" of this kind of thing
is the Standard Atmosphere data. [easy to get] Information on
the millions of radiosondes and (now) rawinsondes takes more
digging (it's of little interest to most other folks) but it's out there.
Next would be basic gas costs and what is required to get from
the supplier's bottle (costs a helluva lot more if the container is
not returned, empty or not) to the balloon itself. That's the
cross-over between work-that-must-be-known-and-done and task
logistics. The "manager" must eventually integrate all the on-board
equipment, cross-check that against lifting capability and make
sure that someone has checked operation VERY close to launch.
There has to be some kind of tracking of the balloon flight and
(unless one has a spare half-million-dollar optical tracker) it is
going out of sight in about ten minutes or maybe 15 even with 10
power binoculars. Supposedly the on-board GPS is doing that
tracking and reporting back accurately...but what if it suddenly
went non-operational? There needs be a procedural back-up.

Now, if the name of the game is Actual Amateur Experimentation,
then the "manager" ought to be able to sweet-talk his way into
getting his own experiment on board one of those already-proven
ham balloon flights. But, that may be defeating the whole object
of this blue-sky to near-blackness-of-space pipe dreaming...
the "manager" won't be manager any more and his name can't head
the list of experienced done-it-before types doing the actual flight.

Or, the project proposals for all this are pure pipe dreaming which
cannot Ever be negatively criticized without getting someone very
outraged for ANY sort of critique except high-fives. Dreaming
about something is fine. DOING it is quite another. Getting outraged
at not being psychologically sugar-boosted happens all the time in
here, realized by most but never by the proposer. :-)

Tsk.

In article ,
(William) writes:

(Len Over 21) wrote in message
...
In article ,
(William) writes:

They need a way to burst the balloon on command (i.e., nichrome wire
wrapped around the balloon plug, a receiver, and a battery),
metallized RADAR reflectors on the instrument chain, and FAA clearance
to launch.

The "command burst" receiver better have some secure coding to
it or some jughead will burst-command it beforehand.

Make that "CBer." There are no jugheads in the amateur service. 8^0

Riiiiighhhht...especially the morsemen who would never Ever
do any wrongness! :-)

A corner-cube reflector can be done with aluminum foil on a balsa
wood frame...just three mutually-perpendicular planes in that
corner cube, less than a foot in any dimension and still good for
skin tracking.

Maybe Kelly could diagram one on the back of an envelope for us?

I've made them. They weigh about a half ounce or so for
1-foot sides (good for reflections down to transponder
frequencies of 1.1 GHz and up to X band. Little ones for
X-band (and some C band) search/weather radar can be a
few inches on the side. Balsa wood strips for the edges
and ordinary kitchen aluminum foil for the reflector.

Corner cubes are extensively used in optics/laser benches.
Those are just three planes of reflectors, each perpendicular
to the others. No matter the azimuth or elevation of the
source, a reflection goes back on the same direction vector.
Ideal for a positive radar return in any azimuth or elevation.

According to Mike, the FAA is "accommodating." :-)

They've lost all sense of jumor since 9/11

The air controllers weren't too happy about the comms outage
(including the backup system) at the Los Angeles Center, either!

Back in the 60s the weather folks used to loft a quarter million or
so weather balloons per year...with little transmitters in them and
telemetry done with extremely low-cost electronics. Good example
of doing things simply and for low cost per launch.

They still do. It is called a rawindsonde and the rawin observations
are transmitted over the weather networks and shared worldwide. These
ballons often reach 10MB, but the payload is much smaller than most
EOS amateur projects.

I had one cluttering up the workshop since the 60s. Military type by
the markings. One-shot battery, a simple aneroid bellows driving a
printed-circuit rotary switch to kick in temp and moisture and light
sensors, all of them variable resistive types that changed the rep.
rate of a simple pulse modulator for the combination RCA pencil
triode and cavity oscillator assembly and inverted ground-plane
antenna.

That must be why the ground operator had headphones and counted
clicks. It's a lot different today.

Not quite. The USAF launched this one I had in the mid-1950s.
Guess where? :-)

They used a tracking radar receiver on the ground and recorded
the telemetry frequencies (of the rep rate) for altitude, temp,
and humidity. Azimuthal accuracy was as good as the boresight
of the tracking antenna (with some corroboration of altitude by
tracker's elevation at close ranges).

All of that went in the dumpster long ago except the
translucent plastic sleeve on the Xmter assembly went two weeks
ago (found it in a box of junk after sorting out the workshop).

Best place for all that stuff.

Perhaps. :-) RCA's tube works had a steady producion of
pencil triodes with crimped-on cavities formed by thin sheet
metal. They made millions of units over a couple decades.
Was a fairly cheap combination tube & cavity.

Those same pencil triodes were later used in a small boat
radar unit made by Bonzer. Flattened disk kind of radome,
had a planar array of helix antennas inside. A few miles range,
good for very small boats.

The experiments can be just
about anything you can think of that can be done at that altitude. Most

launches are multi-mission, with both science and Ham fun stuff on
board. And of course the Ham fun can be scientific too.

Hams have had fun ballooning for quite a while, but the advent
of
inexpensive GPS has changed things dramatically. We now fully expect to

get our payloads back! That wasn't the case not too many years ago.

The balloon is usually one of the latex weather balloon
variety. Zero
pressure balloons can be used too, but since they are designed to go up

and stay up for a long time, that would be a more complex proposition.

You need to do some math on that before envisioning such a "low-
cost" approach to get to 100 Kilofeet. Those 8-foot (typical)
"weather balloons" aren't going to get up that high, not even a mass
of them.

You need to consult some (free for the asking) density values of
the atmosphere and some back-of-the-envelope figuring first. Note
that you have to allow for the lifting gas expansion with altitude.
It
is far from the same at 100 kilofeet versus sea level.

Lots of expansion.

Tsk. Mike hasn't consulted a Standard Atmosphere table set yet.

100 kilofeet he will NEVER make with some surplus latex weather
balloons.

Get sponsor, buy new.

Mike is still NOT going to make 100 kilofeet altitude with "latex
weather balloons." [that was his original statement and, by Rules
of Engagement in this newsgrope, he MUST follow that EXACTLY
or be termed a "failure" or "defunct"]

The payload uses Amateur radio for command and control. At the
heart
of

the system is a GPS unit in conjunction with a packet radio. The
telemetry data is sent back to earth and kept track of with a computer.

The computer lets us know where the payload is, where it is going and
how fast, and predicts the landing site. Oh, and it's freeware.

That's going to be a minor cost item. As you will find out, the
balloon structure, its support infrastructure, and lifting gas will
cost more than you think..

It all adds up. Might be good idea to get a sponsor.

Tsk. He gots the "recycling" spirit. Maybe he has a new way
to "mine" helium out of the air or ground? [collectors around some
heliarc welders might work? :-) ]

I was a forecaster for a "round-the-world" balloon venture. They lost
their helium due to a fabric tear. Couldn't find enough replacement
helium in Argentina.

Most helium still comes from Texas. :-)

In addition, the packet radio can send back other info as the
mission
may desire. The mission is often controlled by a microprocessor. To
date, a lot of balloonatics use basic stamp controllers.

Often a repeater is put on board. A small one has a lot of
coverage at

100,000 feet! There is usually a VHF beacon, and occasionally a 10
meter
beacon also, although that is not as prevalent as it was before GPS.

Two words: Payload weight.

You can't get up in the blue sky with lack-of-detail blue sky ideas.

If it were that easy, lots and lots of folks would have done so a
half century ago.

And all of those gps, beacons, packets, thermistors, pressure
transducers, and video cameras and ATV transmitters operate off of
heavy batteries. Luckily the ascent and descent won't be that long,
and the batteries can be scaled back from what is normally required
with one caveat. You'll want the beacon to be operable for several
days, if possible.

Mere details. It is "doing science!" It is "inexpensive!"

One-shot batteries are one source, but they ARE truly one-shot
and can't be recycled afterwards.

I'm sure our multi-disciplinarian engineer who's "been there and back"
could do it.

Absolutell! :-)

The experiments vary. One of the favorite devices for the grade
and
middle school kids is something called a pongsat. This is an experiment

that can be anything that will fit inside a ping-pong ball. Sounds
weird, but there are plenty of small scale experiments that fit the
bill... er, ping-pong ball.

The balloon lifts the payload to the predetermined altitude,
and
bursts. The payload drops, and the Ham comms can continue during
descent, although the first few moments after burst can be pretty weird

as the payload often does some pretty strange gyrations until the
parachute can grab some atmosphere. Drops like the proverbial rock.

All this time, the GPS is keeping track of the whereabouts of
the
payload.

Commercial grade GPS recievers are designed to not work above 60,000
feet. Crazy precaution against strapping one to a missile and using
it as a guidance system.

No sweaty-dah. Seal the GPS unit in more balloon material, it stays
in a local pressure regardless of the vehicle altitude. More or less.

The ascent and descent shouldn't be more than 4 - 5 hours.

Descent much faster. :-) That weather balloon will probably
go POP before 50 kilofeet.

[someone finally noticed that those balloon things filled at near
sea level DO get rather BIG at high altitude...like, no kidding?]

Then at landing, it turns into a foxhunt as the hams use the
beacon transmissions to find the payload. With the advent of us getting

used to the software and the precision with which the GPS can determine

the location, it is not too uncommon for the recovery team to witness
the landing.

Launch of one of these things does not take as much
bureaucratic red
tape as most people think.

You've done that? You are going to the edge of the stratosphere and
think you can do so freely? Ain't quite that easy.

And it can be done for surprisingly little money.

"Surprisingly little" is a highly subjective term. Real projects
have
quite objective, finite budgets.

The people that are needed are of course Hams, and people with
some
programming experience. People with experience building things, and a
meteorologist can't hurt! People that don't mind a drive on a weekend
day to serve on the recovery team. Plenty of subteams, such as payload,

publicity, science, visualization, integration, education liaison. Even

people that might just want to feed all the other reprobates.

Sounds like you've already filled the "executive" position. :-)

This is real stuff. This might spark the interest in science in
some
youngster. And that is not only a career choice, but a service to the
country. American scientists are becoming pretty rare.

"Becoming pretty rare?" Not quite as any visit to academia will
show but feel free to get opinionated.

Its great publicity for Amateur radio.

It will get ham radio noticed, but what is written up by journalists
may not be what you expect.

Free ballooning has been going in the USA since 9 January 1793,
the first American flight by Frenchman Jean-Pierre Blanchard,
lifting off from the Walnut Street Prison in colonial Philadelphia.
That was witnessed by none other than President Washington.
[from "Lighter Than Air Flight" by Lt. Col. C. V. Glines, USAF,
Franklin Watts Inc., NYC, 1965, data from pp 29-35] That's over
two centuries of time...

And we can innovate and experiment. Radio is a pretty mature
science
now. It's doubtful that any of us are going to invent a grand new
communication scheme, or an antenna that does DC to daylight, or even
one that is a whole lot better than what we have now. So What we need
to
do is to integrate what we have now, and do some innovation with it. We

also need (or at least should) prove our worth to the community.

That we can do it while having fun is a real bonus.

You can have all your innovative fun doing many, many things.
Until you find out what helium costs to lift the total balloon (the
balloon itself, its payload, its carrying structure, its all going to
be a pipe dream having no more basis than enthusiasm.

Check out the prices for helium with a gas supplier, plus what it
takes to haul to HEAVY gas cylinders to a launch area, plus the
metering system plus the filling system plus whatever else. All
that after you've investigated what the actual lifting capacity will
be in terms of ounces per cubic feet of balloon. [I said ounces,
not pounds...lighter than air does not mean negative weight]

You could get "efficiency" by going for hydrogen gas...which is
offset by very direct DANGER from many and varied sources.

Yikes! If they use the nichrome wire on the balloon plug trick...

Hydrogen is a very efficient lifting gas. It CAN be generated by
amateurs...chemistry amateurs. Getting into the balloon is going
to be tricky.

Friend of mine had a hydrogen generator for launching balloons on
Antarctica. I guess it was cheaper/less weight than hauling in
helium.

Surplus catalogs used to sell the little generators but haven't seen
them in years.

It's high school chemistry time. Electrolysis...separate oxy and
hydrogen from water via electrickery. Takes a while for any sort
of H volume but that can be automated. Water cheap, electricity
relatively cheap. [some hams extremely cheap...[


Still going for 100,000 foot altitude? Start thinking in terms of
the balloon exapanding to something on the order of EIGHT times
in size at altitude maximum. That's visible on some of the high
altitude research balloon flights of the 1960s using lots and lots
of plastic sheet for balloon material.

Your project may need a virgin...such as Richard Branson...to
help start it off.

Now, if you are REALLY thinking about this whole thing, look into
"Project STAR" and a little thing like a model airplane that crossed
the Atlantic (from Newfoundland to the Irish coast) during the 38
hours in August 9, 10, and 11, 2003. Laugh all you want but a few
guys from around DC managed to do that through GPS guidance
on board as an autopilot. You can read about it at

http://tam.plannet21.com/index.htm

Pictures and stuff to guide you even if you are not into model
flying.
38 hours (approx) of powered flight using only 5.5 pounds of fuel,
flight path of 1882 miles. Radio control only for take off and
climb-
out, then landing in Ireland...the rest entirely on "autopilot." It
had
some means of reporting its position to earth via satellites. That
alone would be of interest to anything else involving GPS location
or guidance.

Search around on the huge NASA website for atmospheric info,
especially for density versus height. You could do an approximate
curve of payload + balloon weight versus cost of helium in hundreds
of cubic feet to whatever altitude limit. That will give you some
realistic viewing into feasibility of it all.



Sounds like fun. Dense air operations in the eastern states may pose
a big problem.

Not to worry. Air carriers are on the "Victor" ways above the max.
balloon altitude. General Av types will be in the denser altitudes
and props will chop it up nicely. :-)

I wouldn't count on it. Maybe CAPman can fly by with a skyhook and
snatch the descending package before it becomes FOD for the General Av
types?

A large budget bump there...CAP is unlikely to pay for the
snatch aircraft fuel, maintenance costs, etc.

Anyway, this entire thing is highly doable as it's already been done
by amateur radio operators for at least a decade.

Well, YES, it has. Thing was that Mike was making out like it was
something "new" in going to "near space!" NOT with surplus latex
weather balloons he aint. A mylar or other polymer film gasbag,
yes, but the ground support for anything sizeable is going to be
MUCH larger than realized for that "near space" altitude.

Then there are all of the high-power amateur rocket types who
regularly get FAA approval, have telemetry, and a good set of binocs.
I participated once with another amateur and they were thrilled with
our ability to communicate from the launch area to the pick-up area.
Today, FRS and cell phones can probably fill that niche. Ooops!

Darn it! Brian! You said some naughty words! You will now be
lectured interminably by the S. :-)

Len Over 21 wrote:

Dreaming about something is fine. DOING it is quite another. Getting outraged at not being psychologically sugar-boosted happens
all the time in here, realized by most but never by the
proposer. :-)

Tsk.

This reads like the story of your entry into amateur radio, Leonard.
Dreaming about getting that ticket is one thing. DOING it is quite
another.

Mike will likely see "Leonard" at 100k feet before you obtain an amateur
radio license.

Happy psychological sugar-boosting and message knuckling to you.

Dave K8MN

In article , Dave Heil
writes:

If you break 100,000 MSL we'll ship Leonard off to Sean O'Keefe at
NASA so that O'Keefe can pin astronaut wings on Leonard.

HOWL! Now that's funny!

Yes, it was incredibly funny, yet there are those who think that there
is a lack of humor in r.r.a.p.

I like W3RV's idea. I thought it might be more appropriate to consider
naming the vehicle itself "Leonard" but I was advised that there is
already a gas bag with that name.

Remember, too, that the balloons Mike is considering obtain their lift from
helium (a noble gas) rather than hot air.

73 de Jim, N2EY

In article , Mike Coslo
writes:

Leo wrote:
On Mon, 15 Nov 2004 21:24:23 -0500, Mike Coslo
wrote:

Leo wrote:

On Mon, 15 Nov 2004 19:50:46 -0500, Mike Coslo
wrote:

Len Over 21 wrote:

It's times like this that can bring people together. You and Brian
Kelly have something in common.

Realism?

Perhaps you could tell me, Leo? I've shown that it can and does happen
and that a lot of people are doing exactly what I speak of on a regular
basis. Believe or don't believe. It is your choice.

Mike, my point was that you have two folks with a fair amount of
knowledge and experience taking the time to give you feedback.

Who are they, Leo?

Who on this newsgroup has even attempted to launch a radio-carrying ballon to
100,000 feet? Or even to half that?

They
aren't saying that you're nuts to be considering doing what you intend
to do, but they are offering you the benefit of their understanding of
engineering and physics as it pertains to your project.

Perhaps we've been reading different posts...

If they are missing something (and me too, perhaps - this sure ain't
my area of expertise either!), then by all means show them where
they're wrong - but they are both pretty intelligent, educated and
knowledgeable guys, with years of real-world experience in their
fields - maybe worth at least a rational discussion? Or you could
throw a bunch of web references in their faces and get angry....

Your call.

Leo,

There is a world of difference between someone like Jim, who questions
and looks at my answers, and one member that says what I am considering
is impossible, and yet another that calls me incompetent.

At least two out the three are willing to look at the websites.

And there is a lot of difference between me illustrating my points wit
web references, and finally getting annoyed after I am called incompetent.

Considering that to Len, this is an impossible task, and that Brian
Kelly has thinks I'm an idiot that is only suited for cheerleading, I
would have to say that they probably don't have anything to offer me in
my doomed project with which I am going to hurt someone.

My call.

The websites offer a lot of evidence that it can be done, has been done and
even how to do it.

73 de Jim, N2EY

PAMNO (N2EY) wrote in message ...
In article , Mike Coslo writes:

This whole thread got started when I mentioned
that I was putting together this operation in response to Hans' telling
us about how Amateur radio is being marginalized.

And you presented some very good ideas.

Then it turned into me
trying to tell the group about what we were trying to do amidst a couple
people that don't believe it can be done.

Also a bunch of us who know it can be done and is being done, but who didn't
know much about it until you brought up the idea.


I apologize Brian. Call me incompetent any time you like. It was a
mistake to bring this subject up in here, I'll admit that.

I disagree, Mike. Hans brought up a good *policy* subject, and you continued
the discussion.

I bring my hockey mentality in here most of the time. This was too much
of a crossover into my professional mentality. And it is apparent that
it won't be differentiated.

By whom?

At least W3RV was willing to look at the websites you mentioned, and realizes
it has been done. And while there may be some problems doing it in EPA, the
basic concept is workable.

Len apparently has simply *refused* to even look at the information you
presented.

No way, he surfed 'em and you can bank it but he doesn't have the
gonads to 'fess up and admit he was wrong. As usual.

So I guess it's back to talking about the Morse code test! 8^)

YES! QRX while I dial up Carl Stevenson on the other line . .

Nobody's done that for a while!

73 de Jim, N2EY

w3rv

William wrote:
Mike Coslo wrote in message ...

I still might.

- Mike KB3EIA -


Mike, be nice.

I think you have a good project, and cannot understand why all these
"movers and shakers" of RRAP keep poo-pooing the idea. Maybe they are
paper tigers, code-tape Extra's, or just plain old windbags
themselves. Anyway, you have several of them in your backyard and I
haven't seen a single one throw in with you yet (but then I haven't
read all of the blabbering). Speaks volumes.

(

My best advice is to associate the project with a Scouting
Troop/Venture Crew, or H.S. honors science class, etc, find a handful
of sponsors (easier when you have the scouting affiliation), and find
some motivated no-code Techs who aren't afraid of a challenge, or
maybe don't know enough to get out of the way.

A good idea, Brian. I've made a few presentations on other subjects
with the scouts, and it has been a lot of fun.



FWIW, the military has standing orders to assist the Scouts wherever
they can.

That I did not know.


They might be helpful in many ways, from lodging to launch
location to weather support. You could make a request to the Air
Force Weather Agency to have a Support Assistance Request (SAR) in
place to run the trajectory model and predict the final resting place
of your package (you supply launch time and ascent/descent rates),
preposition your recovery team in that vicinity, then adjust as
real-world conditions dictate.



This is a gold mine of a post, Brian. Thanks much!

- Mike KB3EIA -

Subject: Near Space Science - was They just don't get it!
From: Mike Coslo
Date: 11/18/2004 7:42 AM Central Standard Time
Message-id:

William wrote:
Mike Coslo wrote in message
...

I still might.

- Mike KB3EIA -


Mike, be nice.

I think you have a good project, and cannot understand why all these
"movers and shakers" of RRAP keep poo-pooing the idea. Maybe they are
paper tigers, code-tape Extra's, or just plain old windbags
themselves. Anyway, you have several of them in your backyard and I
haven't seen a single one throw in with you yet (but then I haven't
read all of the blabbering). Speaks volumes.

What speaks volumes is that you, Brain, in one breath make an accusatory
statement, then immediately excuse yourself with ..."(but then I haven't read
all of the blabbering)".

My best advice is to associate the project with a Scouting
Troop/Venture Crew, or H.S. honors science class, etc, find a handful
of sponsors (easier when you have the scouting affiliation), and find
some motivated no-code Techs who aren't afraid of a challenge, or
maybe don't know enough to get out of the way.

A good idea, Brian. I've made a few presentations on other subjects
with the scouts, and it has been a lot of fun.

Started off strong, reasonable suggestions, followed up with sleights and
insults.

FWIW, the military has standing orders to assist the Scouts wherever
they can.

That I did not know.

As they do for Civil Air Patrol, JROTC, ROTC, and a handful of other civic
minded programs.

They might be helpful in many ways, from lodging to launch
location to weather support. You could make a request to the Air
Force Weather Agency to have a Support Assistance Request (SAR) in
place to run the trajectory model and predict the final resting place
of your package (you supply launch time and ascent/descent rates),
preposition your recovery team in that vicinity, then adjust as
real-world conditions dictate.

This is a gold mine of a post, Brian. Thanks much!

It would have been had he been able to start it off without being
insulting and demonstrating his arrogance. He cudda been a contender. He had
to be condescending, instead.

73

Steve, K4YZ

Mike Coslo wrote in message ...
N2EY wrote:
In article , Mike Coslo writes:


Brian Kelly wrote:

Mike Coslo wrote in message

...


1500ºC is 2732ºF, over
a thousand degrees hotter than the melting point of steel!


"That's hot!"


. . WTF . . ?!

The atmosphere does indeed heat up in the area known as the Thermosphere


Does other odd things too. Bouncy, bouncy!

Space, or near space is a very strange place...

If you don't believe me, here is some info from NASA. They give even
higher values as a maximum.


"That's hot!"


http://liftoff.msfc.nasa.gov/academy...tmosphere.html

and

http://en.wikipedia.org/wiki/Thermosphere

gives a nice explanation of the Thermosphere, and there is a bit of info
there as to why Amateurs should be interested in it.


A good question is "Why doesn't everything that passes through the
thermosphere burn up?" Because they don't. In fact, despite these high
temps, things passing through this region would "feel" cold.


Would you rather stick your hand into water heated to 200 degrees F or air
heated to 400 degrees?

Why should Hams know about the Thermosphere?


'Cause it's hot? ;-)

If it wasn't hot, we wouldn't have the ionization that allows us to
communicate all over the world on HF.



You *don't* understand some *very* basic
things about the atmosphere, things that you should know as a Ham.


This whole thread got me thinking about how balloons work and how much helium
costs and such. One thing I found out is that 1000 cu ft of helium can be had
for about $200. A bit of $$ for an individual launch but not much if split up
amongst a group.

And of course you don't need that much per typical launch.

I'd seriously consider using hydrogen instead of helium. Hydrogen
would be a terrible choice for use in party balloons but in a
controlled situation like this outdoors and handled properly hydrogen
can be used quite safely. Hydrogen is used in large volumes throuhgout
the industrial sector and it's being used in experimental hybrid
vehicles. If the pros in the auto biz don't have a show-stopping
problem with hydrogen being used as fuel for the interstate kamikazis
neither do I. Propane is nasty stuff too but propane-powered vehicles
have been out there for 40-50 years.

I believe it's much cheaper than helium.

With hydrogen you wouldn't have to inflate the balloon as much to get
it airborne which in turn means that the balloon would be able to fly
higher before it pops. "Higher stretch ratio", etc.

Another thing was the lifting power at high altitudes and low pressures, and
the concept and behavior of a balloon open at the bottom that's not filled all
the way with gas. Fascinating.

Those balloons get BIG before bursting. I've seen some video of it. I
haven't seen what happens to the form of the zero-pressure balloons,
though. Certainly the zero-pressure balloons are a fascinating example
of a self regulating system.

- Mike KB3EIA -

w3rv

PAMNO (N2EY) wrote in message ...
In article , Dave Heil
writes:

If you break 100,000 MSL we'll ship Leonard off to Sean O'Keefe at
NASA so that O'Keefe can pin astronaut wings on Leonard.

HOWL! Now that's funny!

Yes, it was incredibly funny, yet there are those who think that there
is a lack of humor in r.r.a.p.

I like W3RV's idea. I thought it might be more appropriate to consider
naming the vehicle itself "Leonard" but I was advised that there is
already a gas bag with that name.

Remember, too, that the balloons Mike is considering obtain their lift from
helium (a noble gas) rather than hot air.

73 de Jim, N2EY

What an ignoble thing to say, James.