How much extra HP from burning nitro?

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.

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

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.

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

Sterno worked well enough.

As did the filling of the bag with the gas emitted from Draino and Water with a bit of aluminum foil in the bottle. A fuze for a counter weight always made a fun addition and far safer than a heat supply of Sterno.

Gunner

The methodology of the left has always been:

1. Lie
2. Repeat the lie as many times as possible
3. Have as many people repeat the lie as often as possible
4. Eventually, the uninformed believe the lie
5. The lie will then be made into some form oflaw
6. Then everyone must conform to the lie

I wouldn't know, of course, but I understand the key is using birthday candles. 12 of them. Hold the bottom of the bag open with crossed drinking straws (you will need to jam one straw into another to make them long enough), and carefully drip some wax onto the straws as candle mounts. No one would want to try this, say, on a beach at night with an offshore breeze, because a puff of breeze will fold over the top of the bag and it will catch fire, plunging into the sea and endangering the turtles. There is also the danger that the Asbury Park Press will report that the UFO "glowed red and hummed".

Kevin Gallimore

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.

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:

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 :

In this case, the culprit was not only too ignorant to know about exponents at the time he told his lie, but I would bet that he STILL does not grasp the concept despite all the lessons. To him, the number he pulled out of his ass is only slightly larger than others he's read, and therefore it will forever remain fully plausible.

Below is one of my favorite examples, because the lying is so blatantly self evident and self defeating.

"I dabbled as a reserve Deputy for a couple years"

"a reserve Deputy at night (two years)"

"Worked for 5 yrs as a reserve Sheriff's Deputy"

"I was a Deputy for several years in the 70s"

"8 yrs on the street as a cop"

----------------------------------------

Ah, another demonstration of how someone with a 165 IQ handles being called out for telling ridiculous lies. By telling more ridiculous lies!

"mid 150s"

"165"

What social skills? You regularly claim to be adding names to a death list!

The funny, it burns.

Anyone who talks about his IQ in public has certainly inflated it. It's like talking about the length of your dick.

Thanks.

Ah an online calculator.

I was wondering how you got the aerodynamic drag and the rolling resistance . But a good on line calculator would take the rolling resistance into account.

Dan

Perhaps his real IQ can be rated based on him telling two contradictory IQ fables....

I am sure he does.

. How can you expect folks to take you seriously when you talk

Have you read about Pecos Bill or Pail Bunyan? There is a long history of fiction presented as fact. What I do not understand is why people get upset. I enjoy reading of Gunner's exploits. I think he does a pretty good job of spinning a yarn.

Did I ever tell you about exploring " 23 dollar pit"?

Dan

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.

My experience is very different. I almost never see anyone bragging about their IQ. And I do know a few really bright people. Most of the really bright people do their best to keep their IQ hidden.

It is pretty much like walking on water. You do not want people knowing that you can , because the next thing you know they want you to walk across the lake and get another six pack or two.

Dan

My pal Steve has an IQ of 289 and his Chev Eldorado with a fifth wheel trailer can go over 300mph on nitro and his buddy killed five guys with one punch last night and and

I was lazy and looked for a calculator first. But I don't know the source and so I didn't trust it.

The equation is something I had on hand. So, to check the online calculator, I cancelled out the factors that would be the same at different horsepower ratings and speeds on one particular bike (Cd, A, k) and realized that the equation simplifies to something trivial, IF you know both one particular speed and the horsepower required at that speed.

Which happens rarely, but fortunately there is a lot of documentation about it online because of the unusual agreement between Kawasaki and the EU to speed-limit the bike to 300 km/hr. The magazines all wanted to know what it will do without the governor, and there are several road tests that came up with the 200 mph figure.

And that also happens to make sense in terms of the factors I cancelled out. Those are pretty typical for a big bike with advanced streamlining, like the Ninja.

Notice that the Honda that went 270+ did a bit better with less horsepower (270 with 400 hp vs. 265 with 450), which also makes sense. That Honda is engineered for one thing: setting a world record at Bonneville. Its Cd probably is lower than that of any street bike.

Anyway, the online calculator checks out. Try varying the weight of the bike a bit and see what the consequence is for different values of rolling resistance (that's where the weight factor comes into play). The speed varies very little, you'll notice. That also makes sense.

After 10 years, I have him pegged around 130. And I've always been good at estimating IQ.

He's quite smart. Don't underestimate his intelligence. It's just too bad that it doesn't have better material to work on. d8-)