over speeding

[smcb1]

can anyone explain what this is please and how to tell if it is happening during flight.
thanks in advance

[Gate88]

Am I the only one here who has absolutely no idea what you are talking about?

Should there be a video or a photo or something?

[Ross Northcott]

can anyone explain what this is please and how to tell if it is happening during flight.
thanks in advance

when your going faster than you should be, ie over speeding.

[tonystevens]

Usually happens when your not running a gov to keep the headspeed constant. When the head unloads say in a steep descent, you can hear the headspeed rise. Best using a gov

[panosg]

Usually happens when your not running a gov to keep the headspeed constant. When the head unloads say in a steep descent, you can hear the headspeed rise. Best using a gov

Sorry to highjack op.
Tony I never have run gov on my heli's.Something I been thinking to start doing for some time now.
If I set up gov on my Logo 600 will I then have to run a 0, 25, 50, 75, 100 thr curve? I am running a flat curve now.
Sorry probably a very stupid question, but if I don't ask I will never know

[Ross Northcott]

Sorry to highjack op.
Tony I never have run gov on my heli's.Something I been thinking to start doing for some time now.
If I set up gov on my Logo 600 will I then have to run a 0, 25, 50, 75, 100 thr curve? I am running a flat curve now.
Sorry probably a very stupid question, but if I don't ask I will never know

What speed controller or gov you thinking of using?
With mine kontronik esc iam using the built in governor, and i adjust it through the throttle curves, always use a flat line curve in idle 1&2.

[panosg]

Hi Ross
Using the Kontronics 80HV ESC and full size vbar 5.2.
Don't get it . If I use flat curves on my throtle curves is this not the same as using a gov? Confused.....lol

[stanley1]

if mode 4 or mode 11 is programmed then yes a flat line is governed at that %

[Ross Northcott]

Hi Ross
Using the Kontronics 80HV ESC and full size vbar 5.2.
Don't get it . If I use flat curves on my throtle curves is this not the same as using a gov? Confused.....lol

The kontroniks has a built in gov (i'am using mode 11), so you use a flat line throttle curve, cant remember how to disconnect the built in gov, i think you have to remove one of the wires but again iam not sure 100%, maybe someone can confirm.

[tonystevens]

Im the same as Ross, using mode 11 on the Kontronic with a flat line IU curve. A flat line curve as far as im aware wont make the heli work the same as a gov'd one because the power is kept at the constant % you set on your curve and you will get overspeed when the head unloads and underspeed as the head loads up. The gov will keep the headspeed constant as you load/unload the head. If your using a kontronics esc you may as well use the gov, its a bloody good one lol. Just set mode 11 and keep your curve flat.
What mode are you running?

[Steve]

In a nutshell............

Helicopter head control works best when the head speed is constant throughout the entire flight envelope. This is true for full size helis as well as model ones. Head speed is mechanically controlled by the amount of cyclic and collective pitch on the main blades (i.e. resistance), and the amount of power delivered to the drive train (i.e. throttle). This can be achieved by playing a balancing game of collective pitch (i.e. resistance) against throttle input (i.e. power), which is why we have pitch and throttle curves available to us on our transmitters.

Sometimes (.....quite often), this can go a bit haywire when gravity and aerodynamics take over the basic premises, and the head can over-speed the design value as our mechanical control values become over-stretched. A good set of throttle curves and pitch curves, coupled with some decent engine tuning will go a long way to making sure this doesn't happen, or is at least minimised.

Alternatively, and more commonly, people use a governor (a little box of electronic wizardry between the receiver and the throttle servo) that measure the head speed in flight and automatically governs and controls the power delivery, without you having to worry about it. So, you get almost perfect head speed, no matter what you're doing inside the envelope.

To quote Pete Christy's signature.... 'No matter how hard you try to push the envelope, it will still remain stationary.'

[tonystevens]

Good post steve, and as you said, 'in a nutshell'

[smcb1]

yeah Steve thanks this make some sense now and i can hopefully tweek my setup to reduce the possibility of this. Thanks again