Stick position

[asra]

Ross, The questions you raised about how to fly a gyro are best put to an instructor, as Alan Wardill will atest to, that I constantly do privately because its a private matter.Because this is a public forum, I will continue to take the opportunity to raise issues that seek answers to questions, that you unfortunately think is outside the square. In some ways I feel sorry for you having a closed mind.Ted

[Echo]

Ted, I have met Ross & have seen him fly , I can assure you he doesnt have a'closed mind'. I think you are confusing progress with the simple enjoyment of flying. Which questions about how to fly a gyro did Ross raise that are best put to an instructor? You said yourself this is a public forum , lets hear it. " ..a poor cousin to the US forum..." Not in a million years would I like to be compared to 'them'.

[asra]

Eric,"How about you post some questions on how to fly a gyro, how to land it in a cross wind.......etc, these appear to be the issues you need to address.The answers you get to these questions may help you at your stage of training".Ted

[asra]

Eric, Of the four questions I posted, we have at the time of this post 1043 views and only 75 posts. Lets find a way to increase the posts , by letting the ideas flows. You never know if something may arise which could lead to an improvement in the sport.I know you post a lot and for that I thank you.Ted

[Echo]

You know what I really miss,Ted? Paul Bruty's input.[^]( I still reckon this little guy looks like Paul)

[asra]

Yes maybe we should extend an invitation to Paul to post again. I see him online at the American forum but he's not really into posting there either.Ted

[Waddles]

Gentlemen,I have emerged from the cave for a short while, hence my opinions.The side stick concept originally appeared in military aircraft which were actually flown by computer inputs. Now I know someone will correct me here. However, the fact remains that the side stick inputs data into a computer which then orders the appropriate control input. Even with the original B 747, the control column inputs actually provided commands to a central control actuator which controlled the amount of hydraulic pressure directed to the appropriate place. Feel or feedback that the pilot feels is artificially generated. Remember that these control inputs, whether direct or via hydraulics or computer, actually move small surfaces which cause the major aerodynamic member to move accordingly.Consider an aircraft wing. The pilot does not move the entire wing directly. He moves the ailerons which subsequently cause the wing to change direction or orientation, whatever. What happens in a gyro? Do we move small surfaces against the ambient air pressures, or do we move the whole aerodynamic surface manually? I think the latter.So Ted, in reality, you need a side stick to command a hydraulic actuator(s) to provide the necessary movement of the entire rotor disc. Manually with a side stick, it is not possible in a gyro.Let the bullets fly.Waddles.

[Tim]

quote:Originally posted by WaddlesConsider an aircraft wing. The pilot does not move the entire wing directly. He moves the ailerons which subsequently cause the wing to change direction or orientation, whatever. What happens in a gyro? Do we move small surfaces against the ambient air pressures, or do we move the whole aerodynamic surface manually? I think the latter.G'day Allan, good to see you out of your cave. In my opinion I think you nearly got it (or you did got it and I couldn't quite follow). As you said, control would be easy if you could move a small servo, trim tab or aileron at the tip of the rotor, but the complications of the mechanisms involved makes this impractical. Instead we use the joystick to tilt the teeter bolt and cyclicly change the rotor pitch, which then supplies an aerodynamic force to the disc, which precesses the whole disc its newly commanded position.In some quick manoeuvers the joystick forces become quite high and I agree that they would be too heavy for a computer style joystick.Tim McClure

[NiqueNaque]

Alan,With the fixed wing, the aileron may move, but what it is doing is increasing or decreasing the coefficient of lift (COL) on either side by changing the shape of the wing (ie, bending the aileron down / up). This in turn alters the forces acting on the a/c with respect to its COG. ie, roll left - increase COL on right wing- lift it, decrease COL on left wing - lower it. The same may apply to pitch and yaw, unless the elevators or rudder are fully flying.. in which event the entire surface is moved. No doubt you know all this, but it is here for the benefit of others who may not know it.A gyro is not terribly different from this, we vary the angle of attack on the rotor blades in their flight path around the rotor's axis to achieve the same effect, you may find the rotor thrust vector (RTV) is rotated about the pitch and roll pins in the rotor head in sypathy with the joystick. This moves the line of the RTV forward or onto the COG of the gyro in pitch to nose up and down, I'll note it is not good practice according to Greg Grimminger to take the RTV behind the COG as this may cause a bunt over. The gyro is rolled left or right by moving the RTV to the right or left of the COG. Don't forget that the RTV in normal flight is equal to the weight of the gyro, say 350 lb for a single seater, this represents a very large force and a large moment, hence the sensitivity of gyros in flight with respect to stick movement.Jeff Henly Smith has a side stick on his gyro, though with a *significant lever arm*, enough that he has a large mechanical advantage over the student pilot in front and requires large control inputs. It is not as fancy as an avionics version of a joy stick, but it works.Hope this helps,Nick.

[NiqueNaque]

Ted,Coincedentally, congratulations on becoming the new broom...Cheers,Nick.

[asra]

I am with Ross on this one Ted. It is sound advice to stick with the kiss system until you have sufficient experience for radical thoughts not to become potentially dangerous.Pete

[asra]

TedIf you want to get some very comprehensive gyro information, ASRA has a great library. If you contact Richard you can arrange to borrow some of this stuff.Richard is also the designer of the (soon to be legendary) Douglas Reduction Drive.LibrarianRichard Douglas9 Kaneruka PlaceBaulkham Hills NSW 2153AustraliaPhone: 02 9674 4467E-mail: ricdoug@bigpond.com RegardsRoss B

[asra]

quote:Originally posted by NiqueNaque I'll note it is not good practice according to Greg Grimminger to take the RTV behind the COG as this may cause a bunt over. Nick.Nick, You got that backwards. The RTV needs to be BEHIND the GoG for stability. That way, when lift increases the nose will move down, and when the lift decreases the nose will move up.

[asra]

How we are getting somewhere. Thank you to all those who have put forward some constructive comments in this thread. Now we can start to understand some of this issues.For those of you who are espousing "get some training" you are clearly on the wrong side of the fence. Hopefully you'll give up and stay out of threads like this.Ted

[Waddles]

Gidday All,The bottom line is that we actually move the whole wing with our control inputs, not a small section of the aerodynamic surface. Even with the B747, over zealous use of the controls will be manifested by the onset of stall buffet caused by the inability of the airfoil to react instantly to the rapid control input. In this situation, wing flexing is alarming if one happens to be looking there at the right time. I think that the gyro system is a good move in that with the correct set-up, over-control is difficult. No doubt, in some circumstances rapid response to control input is desired, but for the average sport flyer, it is not desirable especially if the pilot is a low time bloke. The result is called PIO and it kills people.Another shillings worth in the pile.Waddles.