How much extra HP from burning nitro?



I made my paper balloons from instructions in a magazine that described how to lay out the gore pattern for a sphere.
Polyethylene cleaners bags worked almost as well for minimal effort, and didn't alarm the neighborhood with a bright flame when they ignited. IIRC the ring was split bamboo and the cross wires were strands of picture hanging wire. I hung them on a tall stake to inflate them with a tiny campfire and then put alcohol-soaked cotton balls in the aluminum foil cup for the flight.
The flame made the balloon glow like a Japanese paper lantern. This is a good description: http://www.ufoevidence.org/Cases/CaseSubarticle.asp?IDB7
That one wasn't mine. At that time I was pulling my pranks in college a few towns away. A hot-air balloon could lift a few cells from a disassembled 9V battery and these light bulbs : http://www.advantagehobby.com/137114/MDP391/?pcat 16 or series-string (low voltage) Christmas flashers.
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On Wed, 27 Feb 2013 08:09:07 -0500, "Jim Wilkins"

This could be fun to build...add some lighting....

http://www.youtube.com/watch?v=qb_ACMSG_hc

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http://www.scientificsonline.com/professional-weather-balloon.html
"Professional Weather Balloon, One 16 Foot Balloon, 100 Cubic Feet (3072151) $79.95
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On Tue, 26 Feb 2013 16:34:01 -0800, "PrecisionmachinisT"

Ok, but we were talking about tissue-paper hot-air balloons.
I have a funny story about those weather balloons, and my 8th-grade buddy's hydrogen-generating apparatus, with zinc chips and some kind of acid, but I'll spare you. <g>
--
Ed Huntress

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Aww come on Ed...
--ya probably already told about it once, just that we've both done forgotten.
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On Tue, 26 Feb 2013 19:13:08 -0800, "PrecisionmachinisT"

I don't think so. Let me just cut to the end, where the newly laid tile in my friend's basement turned into a puddle of silly putty...go easy on the zinc, we learned. <g>
--
Ed Huntress

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I vaguely recall making rockets using zinc powder and sulphur as a propellant, of mempry serves me, the usual exoected progagation rate was something like 900 fps
Pretty sure it's no longer being recommended, good mix / packing job basically becoming a pipe-bomb
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On Tue, 26 Feb 2013 19:56:41 -0800, "PrecisionmachinisT"

That was the formula promoted by Scientific American back in the '60s. They had a chapter on amateur rocketry in _The Amateur Scientist_ and I remember the formula. They said it was a lot safer than black powder. I should hope so...

There's supposedly something a lot better.
The formula I was talking about was just pieces of zinc spatter in (I think) hydrohloric acid. We got plenty of hydrogen -- and a boiled-over beaker of acid. <g>
--
Ed Huntress
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The estes still make for a fine bottle-rocket, scrape the clay parachute-launch barrier loose to expose some actual fire to your burst-charge, which can be contained in an end mill tube that's been duct-taped to the top of the rocket tube.
A word of warning, you need a LONG stick and /or you need to attach weughts to the bottom of the stick...the nozzle is the pivot point; if it is not also the balance point ( a top-heavy rocket will overturn if you attempt to balance the nozzle on your finger...if it does, then the trajectory is basically random...the nozzle must ALWAYS stay pointed downwards if you want to shoot for the moon instead of your neighbor's Cadillac.
And then there's the spent carcass...best to do over the ocean, IMO
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On Tue, 26 Feb 2013 21:06:33 -0800, PrecisionmachinisT wrote:

Adding weights at the bottom is wrong way round -- the condition for aerodynamically stable flight is center of gravity *above* the center of pressure. Eg see following and some links from it. <http://exploration.grc.nasa.gov/education/rocket/rktstab.html
--
jiw

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wrote ...

when the

weughts

not

attempt to

is

you want

The goal here was to maintain a self-correcting, straight-up trajectory, not to hit a target located some distance away...
--with the proper amount of weight attached to the end of the stick, they would quickly arc in an upwards direction and assume a purely vertical climb even if launched horizontally.
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On Tue, 26 Feb 2013 16:04:06 -0800 (PST), jon_banquer

Oh, that's cool. I don't remember ever seeing that one.

Get one of the cheap foam trainers. Start with slow movements and don't overcorrect. Overcorrecting is what gets you into trouble.
Combat planes were wild things. They also were easy to build, thankfully. They had no fuselage; all wing and elevator.

I never did it that way myself, but I think that was it. I know they glued a string to the top and held it up with a long stick until it was ready to fly.
My grandmother owned a florist's shop, so my dad had an endless supply of tissue paper. I guess he made green balloons. <g>
--
Ed Huntress

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Ed Huntress wrote:

That yellow battery powered one that HF sells actually flies pretty good, but you will want a supply of wings.....

--
Steve W.

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snipped-for-privacy@whidbey.com wrote:

Just think what a quart of the full strength stuff would do to the engine of one of those idiot's who roar down your street at 3 in the morning, ratting windows for blocks? :)
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I think the issue with a motorcycle reaching those speeds is not so much horsepower as stream lining. After all, if there was no resistance of any kind, you could reach 264 mph with a 1 horsepower engine. The only motorcycles that have reached speeds close to that I know about have had fully enclosed shells. It was clear from Gunner's original description that was not the case. I am not sure why there is so much debate about this. Gunner is a text-book classic sociopath. He will say whatever he thinks he can get away with to gain status among his percieved peers. When questioned, he resorts to threats.
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On Tue, 26 Feb 2013 13:39:24 -0800, "anorton"

I know about the streamlining. That's why I was thinking about how much HP it would take to actually push a sit on bike and rider at high speed. Eric
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On Tue, 26 Feb 2013 13:53:52 -0800, snipped-for-privacy@whidbey.com wrote:

For a bicycle the force necessary to overcome "wind resistance" requires 216,228,92 watts, or 289.96 H.P. at 264 MPH. This, of course, does not include the losses due to internal friction in the engine, rolling resistance of tires and so on, and is calculated solely on cross sectional area, I'm sure.
--
Cheers,

John B.
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On 2/26/2013 5:26 PM, John B. wrote:

You need to know something about the surface area.
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On Tue, 26 Feb 2013 19:12:07 -0800, Jeffrey Fowler

If you're referring to skin drag (versus form drag), that is theoretically included in Cd -- drag coefficient.
It is in practice, too, for the most part, because Cd usually is measured empirically, in a wind tunnel.
--
Ed Huntress

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On Tue, 26 Feb 2013 19:12:07 -0800, Jeffrey Fowler

It was taken from an article on "bicycle aerodynamics" and used a "standard" area (whatever that was). The formula was apparently tweaked by comparing it with actual torque and RPM figures taken from the power meters that are now fitted to some bikes.
--
Cheers,

John B.
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