No swash plate

[gdawg]

I am looking to do some research into creating a helicopter without a swatchplate. essentially i would be using jets of air to tilt the helicopter to create the propulsion (not to dissimilar to the NOTAR).

I myslef see no reason why thsi would not work, but i am certainly no expert and was hoping that someone here could give me some info. specifiically, has this ever been attempted before, and is there any reason that anybody can think of as to why this would not work

[bugdevheli]

Cant resist, I think you will find its called a "swash plate". Can not decide why though! .Perhaps its because a gimble surrounded by a rotating housing carrying the pitch adjustment rods that are connected via a bearing to a non rotating star which carries the movement to the rotating star, which is moved by cyclic and collective push rods which are connected to both the cyclic and collective levers both of which are controlled in their vertical plane by the mixing arrangement etc, etc. On second thoughts why not call it a swatch plate. Bug.

[kwachon]

Would this be a battery operated version or wind up?

[Seymour Belvoir]

Not using a swash plate....Sounds like a load of hot air to me.

[Efirmovich]

gdawg..... Assuming you are changing attitude with some sort of thrust vector how do you propose to increase the lift ?

E.

[JimEli]

for starters try google search "individual blade control"

http://halfdome.arc.nasa.gov/research/ibc.html

http://www.wipo.int/pctdb/en/wo.jsp?WO=1990%2F08063&IA=WO1990%2F08063&DISPLAY=DESC

[Agaricus bisporus]

bugdev - Cant resist, I think you will find its(sic) called a gimbal...

[topendtorque]

how do you propose to increase the lift ?



already answered :{


Sounds like a load of hot air to me.


vertical hot air, that is.

[NickLappos]

The X-Wing RSRA had this control design, using Coanda effect and slots to control the lift distribution around the rotor, and it had a set of impressive valving and slotted air distribution channels, but no swash plate.
From Wikipedia:

Instead of controlling lift by twisting its blades as more conventional helicopters do, the craft used compressed air fed from the engines and expelled from its blades to generate a virtual wing surface, similar to blown flaps (http://en.wikipedia.org/wiki/Blown_flap) on a conventional platform. Computerized valves made sure the compressed air came from the correct edge of the rotor, the correct edge changing as the rotor rotated.

The program ran into many technical problems, none crippling but many expensive to solve and it was canceled. It is worth noting that the air needed to feed the Coanda slots required an extra engine that did nothing but pump air, making it an interesting swap - remove a swash plate and add an extra engine. Not a very good bargain, IMHO.

http://www.dfrc.nasa.gov/gallery/photo/X-Wing/HTML/EC86-33555-2.html

[Dave_Jackson]

bugdevheli posted;
"Cant resist, I think you will find its called a "swash plate". Can not decide why though!"
Definitions:
` swash ~ to make violent noisy movements, to move about very rapidly; dash to and fro.;
` swish ~ to (cause to) move quickly through the air making a soft sound.

Alternate definition: Swishplate ~ A device used to control the behavior of gay blades. http://www.unicopter.com/Whip.gif

Dave

[Revolutionary]

Take a look at the Kaman system of pitch control. Functional and requires neither a swashplate nor a swatchplate.

http://www.helis.com/howflies/servo.php

[slowrotor]

"On second thoughts why not call it a swatch plate". Bug.

Got a good chuckle on that one Bug.

I thought it was some kind of data plate upon scanning the posting list.
Oh well, swatch is just a sample of cloth. (looked it up in the dictionary)

slowrotor

[Um... lifting...]

Gimbel's? Nah, they went out of business 20-odd years ago (pommies see 'Miracle on 34th Street' for context)

http://www.city.pittsburgh.pa.us/wt/assets/images/gimbels.jpg

[Farmer 1]

I think you'll find the Swiss have been working on swatchplates for years.

[Westerntribal]

' has this ever been attempted before '
Yes it was called a sea harrier.
http://en.wikipedia.org/wiki/Sea_harrier

Apparently difficult to fly

A more recent development and very cool clip.

http://en.wikipedia.org/wiki/Image:F-35_compilation.ogg

Apparently very easy to fly ( computers keep it all stable )

I watched a doco on it recently the guys at Lockheed Martin said about 5mins to teach a fighter pilot to hover the thing. Helicopter pilots find it way to easy and get bored..

[bugdevheli]

Agaricus Bisporus. Apologies, stand corrected , slip of the mind, but i find the American spelling of this word seems to suit better. Regards Bug.

[Graviman]

Gdawg - a quick response, as i'm still looking for that quiet evening to catch up on heli stuff!

The main problem with your concept is that the puffer jets would ideally need to be controlled by (laser) gyros. This is because Harrier is pitch/roll acceleration control, but a helicopter is pitch/roll velocity rate control, although low hinge offset means there is a brief period of weak accel control until rotor gets mast to follow. Harrier accel control is apparently intuitive to control at wings level with a good horizon, but requires pilot concentration. For more general flying rate control is preferred.

Have a look at how the Apollo/Grumman Lunar Module linked gyros into the flight control systems for the small attitude rockets to give you some ideas. I'll do some digging if i get time, and there is sufficient interest...

http://en.wikipedia.org/wiki/Lunar_Module

[helicfii]

I believe an air-puff system will work, provided you build the aircraft to be large enough to house a sufficient number of helium bags.

[bugdevheli]

Dave Jackson. I note that in your neck of the woods a swishplate is a device to control the behaviour of GAY BLADES. As with gimble or gimbal,its amazing how the spelling can convey other meanings. eg. hood-bonnet, fanny!!. trunk-boot, etc. over here a GAY BLADE might not mean a blade that is swinging out of track :):):)

[Dave_Jackson]

bugdevheli;


The "Reply to Thread." (http://www.unicopter.com/Temporary/Zorro.wav) :):):)


http://www.unicopter.com/Temporary/Zorro.jpg

[Milt]

Swash/Squash Plates

You chopper pilots will probably find that you have been carrying around a few other Swash Plates than the ones controlling your rotating wings.

Jet engines have duplicated fuel high pressure pumps. Many of these pumps are variable stroke multiple piston pumps with the piston strokes varied by a swash plate which adjusts its angle to vary the pumps output. Maybe your hydraulic pumps are similar.

So - How many swash plates do you need to fly Your helicopter?