is a gyro a weight shift or 3 axis

[OptiFuel]

This is an interresting discussion. How does a pilot control change in pitch, roll and yaw? If It boils down to weather a static or aerodynamic force is used at the end of the day then all aircraft including the weight shift are actually 3 axis. Because with a trike shifting your weight forwards or backwards affects the angle of incedence because of the weight of the cabin,which results in an increase or decrease in lift which is an aerodynaimic force. But if you shift your weight left or right does not have a change in the aerodynamic forces, one wing is simply heavier than the other.

So I believe what we should be looking at is not the resultant forces but how the initial forces are applied as far as defining what is a 3 axis or weight shift.

At the end of the day an aerodynamic force is used to affect change in a gyro, but the confusion lies how the forces are applied to the control inputs. On a gyro, without the WEIGHT of the cabin as a referance one could not affect change to the control rods. Where as a "3 axis" the control inputs are linked to a fixed frame to the aerodynamic forces. There is no way that your arm strength could affect change on a spinning gyro of 14m length, but you can shift a 300kg weight.

Stephane

[John Boucher]

Oh boy....

I thought we had sorted this one out Len?

[John Boucher]

Gyro's are not weight shift.... PERIOD!

Not convinced - check this out - makes logical sense

http://www.asra.org.au/Control.htm

[OptiFuel]

Bad Nav, Thanks for the link.

The confusion to me is that the words "3 axis" and "weight shift" is being used to differentiate types of aircraft when I believe we should be be using "aerodynamic" and "weight shift" to differentiate the controlling force . To my knowledge the number "3" is just the amount of axis that a pilot has control over . Like a gyro would be 3 axis (pitch , roll and yaw) and a Trike would be 2 axis (pitch and roll).

The force applied to control the different axis is either weight shift or aerodynamic. Whether we are talking about the resultant force after an control input or the initial force of the control input changes the way we can define the gyro

As I said in my original post, I agree that the resultant force is aerodynamic and in a gyro a pilot has control over 3 axis .As a resultant control force I agree that it is 3 axis or a aerodynamic force and not a weight shift.

If the definitions are based on initial control inputs then I stand by my belief that a gyro is a 3 axis aircraft using weight shift as a control input This is why I say so:

I quote from the article:

> The truth is that the control is entirely aerodynamic. with gravity acting on the body of the gyro to provide the reference direction. The latter gives the illusion of weight shift which in fact it is not.

The fact that gravity provides the reference direction means that without the weight of the cabin there is no reference for the control inputs. Different to the traditional "3 axis" where the reference is the airframe.. In the article he says that no direct torque is applied to the rotors by the rotor head. But direct torque to pivot the head to create the aerodynamic controlling forces is provided by control inputs that shift the weight of the cabin . The Teeter bolt allows for play and no direct torque only in one direction .

[Gyronaut]

John, you called? lol

I aint going there again... but here is a thought... in a weightless environment, a jumbo pilot wouldnt be able to turn the control yoke if he wasnt strapped into his seat...

EK VOLSTAAN WEER!

PS, nice to see Stephane here, just fitted one of his OptiFuel devices to my Gyro and found him most helpful on the phone.

Will report back on its performance after my long cross country starting monday

Rgds

Len