Concept for radical water speed record rocket boat

Now, that's a cool post.

You've shared a personal experience openly and freely. A little insight into the direct exchange of ideas between you and Arvil and a very nicely established parallel to a developments in another country on a similar theme.

Very nice, Franklin. We'd like to hear more

Chris

 

This is like carrying-on a scientific conversation with my younger sister's Magic 8 Ball.

Has anyone ever told you that you have a mercurial personality?

Let's see, our boy Frank lives in the past with gin stained drawings on bar napkins and faded Pop Science articles; quotes obscure actors from 70's movies and has trouble staying on point.

Yep, mercurial should about do it.

Come on. Frank, put the nonsense and Reagan era detective flicks on hold and go back to the point in this thread where I asked for you to share some of your knowledge. The operational mode here is the word, asked And the asking was done nicely.

You can do that. We all saw a glimmer there with the Soviet torpedo post.

 

The point wasn't that someone in another country was working on a development with a similar theme.

The point was we were nibbling around the edges of a revolutionary concept with potential far beyond what we imagined.

 

You wouldn't be an engineer of some sort, would you Frank?

Not THE point, Frank, but one of several; all contributing to a common theme. Respond to the theme and you'll get yourself back on track.

I was pointing out that you had done a good job of weaving a bit of a yarn in that post and you side-stepped the compliment and yanked a hair splitting exercise out of what was meant as a tribute.

Dude... do you even know how to accept a compliment with a measure of grace, or is the concept so foreign that you just go blewey on all cylinders?

This is the second time you've walked... no check that.. actually, you've run past a nice conversational indicator in order to get at an obtuse angle for purposes of arguing.

You get to keep this thread as all your own, Frank. It's been swell.

 

Porter Concept

Porter specified a 4,000 lbs thrust motor in the stern and two 3,000 lbs thrust motors on the bow. That's almost as much thrust as the big Quicksilver boat.

Donald Campbell's Bluebird had about 5,000 lbs thrust.

At 375 mph 10,000 lbs of thrust is equivalent to 10,000 horsepower.

A tank two feet in diameter and three feet long will hold 70 gallons (812 lbs) of 90% hydrogen peroxide, enough to sustain 10,000 lbs thrust for about 9 seconds.

 

What do you base your thrust-HP comparison? Seems like a number created to justify a point you want to make. If one HP makes only one lb. of thrust the system is terribly inefficient. A one HP outboard makes about 23lbs of thrust. Can you explain the math without insulting anyone?

 

Who gives a crap about efficiency?

The conversion wasn't horsepower to thrust. It was thrust to horsepower. The math for doing that conversion has been around since the dawn of the jet age. For example, at 750 mph one pound of thrust equals two horsepower.

http://www.aerospaceweb.org/question/propulsion/q0195.shtml

http://www.landings.com/_landings/Forums/jb/jb-powerplants.html

Jet power varies with speed; the faster the car is moving, the more power the jet puts out. To find the horsepower, take the thrust, multiply it by the speed in feet per second and divide by 550. (One horsepower equals 550 foot-pounds per second.) Dealing in mph, take the thrust in pounds, multiply by speed in mph, divide by 550, and multiply by 1.47 to get horsepower.

However, the math for calculating the performance of a rocket vehicle dates back a lot farther. In fact over 400 years, to the genius who devised both calculus AND the laws of motion.

You know, F = MA, A = F/M, etc?

You've been given the thrust, the estimated empty weight of the boat, and the weight of the fuel. Now plug in whatever weight you want for the driver and figure it out.

 

To start with, you should figure it out and give the numbers to justify your claims. The formula in the link you provide says net thrust X velocity /550=HP. HP is a unit of work, while thrust is a unit of force. You are not understanding the basic physics. Work is force applied for a measure of time or distance.

 

Really don't give a s h i t.

Not my problem you have neither the comprehension of physics to grasp that once a rocket vehicle is in motion WORK IS BEING DONE nor the basic arithmetic skills to do your own performance calculations by applying Newton's laws of motion.

The only point of mentioning the thrust to horsepower conversion was as a way for the layman to grasp how misleading preconceptions of horsepower based on physical engine size are when applied to rocket motors.

 

In other words, you don't know what you are talking about and think that a bunch of bogus numbers will make us think you do. This is a forum with a bunch of engineers and other technical people that will look closely at whatever claims you make. Either be accurate or be ready to be analyzed and criticised for your mistakes.

 

You can think if you shout loudly enough nobody will notice your ignorance, but the facts are you were FIRST given the thrust, the weight of the fuel load required to sustain that thrust for the needed period, and the estimated empty weight of the boat THEN told Newton's laws of motion and STILL couldn't figure it out on your own.

I came on this site hoping to get some insight into the potential hydrodynamic behavior of Porter's concept, not to give lessons in basic physics to lazy idiots.

 

Rude language and bad grammar does not convince me. Force and work are different units of measure.

 

What part of "not giving physics lessons to lazy idiots" did you not understand?

 

Work

Not only were you given an explanation, you were given an explanation for the explanation. You were first given formulas for converting thrust to horsepower, then you were given links to websites that explained the reasons behind the formulas, then told in plain language that the instant a rocket vehicle is in motion work is being done. Not my problem you're so mentally deficient you couldn't understand any of it.

 

Hello, I'm North American Dreamcatcher. The angle on Arvil's rear wing is wrong, It's not a car. Controlling thrust at three points...bad idea, especially forward where thrust can create vortex's over the hull. The design would be in excess of 1,800 lbs. I don't think there is enough room for htp amount for one kilo run. What happens when one of those foils hits a fish, or worse @350mph? Canard stubs look good but they should be neutral, not positive lift. How are they controlled? How do you control the trim tab effeciently at 350+? Good ideas Franklin...been there. Keep it coming and thank you for the Historical info on the attempts.

NAD