Search found 539 matches

by skyfrog
Mon Feb 27, 2006 10:27 am
Forum: Gas turbine forum
Topic: help in designing a small turbine
Replies: 48
Views: 29783

re: help in designing a small turbine

Please also try Heward Microjet's WASP, as it is smaller, lighter, yet is more powerful than KJ66. it delivers 20lbs of thrust.
by skyfrog
Mon Feb 27, 2006 4:52 am
Forum: Ramjet forum
Topic: Air Turbo Rocket ATR
Replies: 5
Views: 6014

re: Air Turbo Rocket ATR

What thrust figure do you need for your ATR ?

Here's set of plans for KJ66. Around 18lbs of thrust you can get from this turbojet engine.

http://www.pulse-jets.com/phpbb2/viewto ... light=kj66
by skyfrog
Sun Feb 26, 2006 12:44 pm
Forum: Gas turbine forum
Topic: help in designing a small turbine
Replies: 48
Views: 29783

Re: re: help in designing a small turbine

In this case I don´t think the budget will cover a balanced turbine and NGV, and since the engine is not supposed to propel anything it would be overkill to spend so much $$$ on things that can be made with a chunk of stainless and a bit of trial and error... Besides, I fully agree with Zippiot ab...
by skyfrog
Sun Feb 26, 2006 10:09 am
Forum: Gas turbine forum
Topic: help in designing a small turbine
Replies: 48
Views: 29783

Re: re: help in designing a small turbine

i completely forgot, i dont want to make a turbo charger (car or truck) turbine. im looking at the "real" inline turbines. i know saying "real" will get me chewed out but i mean no offense, i am looking for one style that may not be the type you chose... Start with popular books such as Kamps is a ...
by skyfrog
Sun Feb 26, 2006 2:15 am
Forum: Gas turbine forum
Topic: Johansson´s Pocketbike
Replies: 431
Views: 245578

re: Johansson´s Pocketbike

Hi, Would you guys mind if I cut in this topic. Be careful of the lathe, it is very useful in making jet engines, but I think it is even more dangerous than the grinder. Last week I read of a news here about a lady worker cleaning inside a CNC lathe for removing the scraped chips, God only knows why...
by skyfrog
Fri Feb 24, 2006 1:52 pm
Forum: Off topic forum
Topic: Backpack helicopter
Replies: 63
Views: 28210

Re: re: Backpack helicopter

Picture is my own project. Cita Hi Cita, Your helicopter looks great, and your coaxial approach is very unique too, I like it, twin engine config, each drives one rotor in different direction. Just a quick question, how do you keep two engines in synch all the time to cancel out torque generated by...
by skyfrog
Wed Feb 22, 2006 4:41 am
Forum: Valveless pulsejet forum
Topic: SP-22 Constant Flow engine
Replies: 11
Views: 6066

re: SP-22 Constant Flow engine

Congrats Bruno, You finally got the configuration settled down. Hope to see some engines running soon.
by skyfrog
Tue Feb 21, 2006 12:21 pm
Forum: Tools and Construction
Topic: Java applet forum!
Replies: 6
Views: 3208

Re: re: Java applet forum!

PS. Small world it is now hey Horace. I love your site by the way. Ive followd your progress for a long while, but i went for a check up. WHAT is that angle grinder milling machine? Looks like something that i would do. Ha. Id hand hold both a drill and the angle grinder tho. It's a small world aft...
by skyfrog
Tue Feb 21, 2006 8:41 am
Forum: Rocket forum
Topic: Rocket and noise?
Replies: 5
Views: 4242

Re: re: Rocket and noise?

HattoriHanzo wrote:1. I was looking for some formula or empirical estimations to calculate the acoustic power generated by the engine.
Now your question makes sense, I am sure there were empirical data for this. According to a rocket textbook, Saturn V at lunch it emits acoustic power of about 2x10^8W, that's huge.
by skyfrog
Tue Feb 21, 2006 8:14 am
Forum: Tools and Construction
Topic: Java applet forum!
Replies: 6
Views: 3208

re: Java applet forum!

Hi,

Kinda off topic, but I am quite familiar with that school, the NTNU, which is dedicated for training teachers. It is just 2km away from my university, back then when I was a student, I often went to their buffet for cheap lunch and dinner.
by skyfrog
Tue Feb 21, 2006 2:33 am
Forum: Off topic forum
Topic: Backpack helicopter
Replies: 63
Views: 28210

re: Backpack helicopter

Hi,

Found this site, good for beginners who wish to learn more about helicopter aerodynamics.

http://www.copters.com/helo_aero.html
by skyfrog
Sun Feb 19, 2006 10:36 am
Forum: Off topic forum
Topic: Theory of Gravitation
Replies: 127
Views: 57138

re: Theory of Gravitation

Hi Forrest, Found time to read the booklet of theory of gravitation. 2% reduction of weight is amazing, if this has been true why didn't we see any machines based on it unveiled ? Another "cold fusion" event ? edit : From Newtonian theory, I roughly calculated the gravitational potential gain equiva...
by skyfrog
Thu Feb 16, 2006 11:21 am
Forum: Off topic forum
Topic: Backpack helicopter
Replies: 63
Views: 28210

re: Backpack helicopter

Just found this English website, same company,

http://yoshine.com/home.php

I've been tracking the development of this company for a while. Let's see what will happen in the next few years.
by skyfrog
Thu Feb 16, 2006 3:14 am
Forum: Off topic forum
Topic: Backpack helicopter
Replies: 63
Views: 28210

Re: re: Backpack helicopter

Of course it is no secret, Horace. It is not even particularly complex. I am just saying it is complex for an amateur to engineer, especially if the assembly is to be exposed to bending loads, which the shaft 'mast' of such a helicopter certainly is. You can always make it massive very easily. But,...
by skyfrog
Wed Feb 15, 2006 3:06 pm
Forum: Off topic forum
Topic: Backpack helicopter
Replies: 63
Views: 28210

re: Backpack helicopter

Hi Bruno, I enjoy this video very much, thank you. Here's another instance of contra-rotating coaxial rotors : http://www.gyrodynehelicopters.com/qh-50e.htm You can find a drawing of the transmission system in that link. This is no more a secret as it has been 40 years old, or more. I am more intere...