Rotor Blade Loading - Page 2

russ · 25-03-2007, 06:57 PM

I know, I know.........idiots [ me ] want em with all the goodies, so "heavy" they get.

2 seaters are getting more n more popular.............of course they would. Some great 2 seaters are coming along now.
All these "baby boomers" want toys now..........me included.

I think the sooner an all "composite" machine hits the strips, then "light" we will be, and damn strong with infinate life, useing the latest tecko fibres and resins.
Heard the other day these latest "airbuses" have a huge amount of "glass" through em, replaced ally with glass.

Rob P........is also toying with the idea of glass hub bars. Your machine has a glass axle, works a treat.

Can see the day when the single heaviest component in a gyro will be the pilot / passenger

Aussie_Paul · 25-03-2007, 07:05 PM

Quote:

Originally Posted by Bell430

Hi Paul,

When you do your loading calc for the 30 footers, what are you putting in for the hub bar etc. I'm not getting the same number as you.... can you talk me through it, cos I don't want to miss something down the track.

Cheers

Paul

Hi Paul, ever since I can remember gyro people have just used pi r squared to get the disc area, then divide that into the gross weight.

30' diameters rotors r=15' x 15 x 3.142 =706.9. MTOW 1320 lbs divided by 706.95 =1.8671

right or wrong, that is how I have always done it.

Aussie Paul.

Birdy2 · 25-03-2007, 09:01 PM

Can see the day when the single heaviest component in a gyro will be the pilot / passenger
That day passed years ago Russ.

right or wrong, that is how I have always done it.
So i spose your answer could be rite or rong too then.

Fencing Wire · 25-03-2007, 11:09 PM

Quote:

Originally Posted by Aussie_Paul

Hi Paul, ever since I can remember gyro people have just used pi r squared to get the disc area, then divide that into the gross weight.

30' diameters rotors r=15' x 15 x 3.142 =706.9. MTOW 1320 lbs divided by 706.95 =1.8671

right or wrong, that is how I have always done it.

Aussie Paul.

Some fairly dodgy looking math, there Paul.

I can't remember what "disc area" constitutes now, but it is probably a misnomer. If it is the circumference of the circle, then it is pi D. (or 2x r x pi). It it is the swept area of the blades, then it will be 11/14 D squared.

Squaring the radius x pi doesn't seem to relate to anything. But since I went to school about the same time as you, then it could all be totally cocked up with the mists of time.

bones · 26-03-2007, 07:45 AM

Quote:

Originally Posted by Fencing Wire

Some fairly dodgy looking math, there Paul.

I can't remember what "disc area" constitutes now, but it is probably a misnomer. If it is the circumference of the circle, then it is pi D. (or 2x r x pi). It it is the swept area of the blades, then it will be 11/14 D squared.

Squaring the radius x pi doesn't seem to relate to anything. But since I went to school about the same time as you, then it could all be totally cocked up with the mists of time.

Sorry there Cobb&Co, but PB is dead right on the area of a circle, ie disk area, it is definately pi x r sq.
Damn does this mean i have agreed with PB on some thing

see told you i am a changed fella

Aussie_Paul · 26-03-2007, 08:52 AM

Quote:

Originally Posted by bones

see told you i am a changed fella

I can see that Bones.

I am most impressed.

Aussie Paul.

Murray Barker · 26-03-2007, 03:46 PM

Jeff is making his hub bars 1.25 inches thick now? Why? To me that is going the wrong direction, the fatigue is still going to go somewhere, ie:blade straps, blade root and so on down the line.
From the little I have seen of Magni and MT03 this is one area they have right.

bones · 26-03-2007, 04:41 PM

Quote:

Originally Posted by Murray Barker

Jeff is making his hub bars 1.25 inches thick now? Why? To me that is going the wrong direction, the fatigue is still going to go somewhere, ie:blade straps, blade root and so on down the line.
From the little I have seen of Magni and MT03 this is one area they have right.

Add to that the Air Copter blades that The Xenon use, interesting difference the Europians have they seem to be on to something with this i think..

russ · 26-03-2007, 04:57 PM

Onya there bonesy.........don't miss a chance to plug ya new toy.........." them europeans mite be onto something" .....aye what........Exeon slipped in there aye.

Ol "PB" was ......is bashin us with the flame chook.........now you is slippin em in too regarding the exeon.

You smooth talker you..........

Fencing Wire · 26-03-2007, 08:36 PM

Quote:

Originally Posted by bones

Quote:

Originally Posted by Fencing Wire

Some fairly dodgy looking math, there Paul.

I can't remember what "disc area" constitutes now, but it is probably a misnomer. If it is the circumference of the circle, then it is pi D. (or 2x r x pi). It it is the swept area of the blades, then it will be 11/14 D squared.

Squaring the radius x pi doesn't seem to relate to anything. But since I went to school about the same time as you, then it could all be totally cocked up with the mists of time.

Sorry there Cobb&Co, but PB is dead right on the area of a circle, ie disk area, it is definately pi x r sq.
Damn does this mean i have agreed with PB on some thing

see told you i am a changed fella

Yeh, Mark. I know. Just winding the old fella up. 11'14 x D squared is the same as pi x r sq. Didn't think it would do any harm for him to dig out his old school books.