Scale Soaring UK

Hi all,

Do you think a proportional or on/off throttle is better for a front electric sustainer (FES) to achieve rise off ground (ROG)?

My other FES has on / off throttle when launching from a dolly, but wonder whether proportional throttle might be better for feeding power in and keeping the prop off the ground.

Thanks

Phill

Proportional throttle is always better in my opinion......if you must use an on/off switch be sure to program a soft start and a ramp up of power.....

And one more thing.....to prevent prop strikes on take off be sure to hold full back elevator stick on roll out and release it once you break ground.

That’s what I do in this video....

Like Tom says, throttle is way better proportional - you can cruise!

On my 1:3 Ash26 there's around 2.5Kw on tap so it's nice to feel in full control rather than at the mercy of a switch, my EDF on the Valenta 213 is also on the throttle, this could more easily be a switch operated job, with a delay on the same switch as the up and go movement - horses for courses. There is no wrong way really.

Ell.

I have used flight modes to select the throttle stick for motor in Power mode or brakes in Landing mode.
Easy enough to do on Frsky gear & probably possible on other sets.
As long as you can flick the mode select switch in a hurry, you can always go around if the approach ends up wrong.

Yes, that's a good point Peter, I use phases/modes too. In Powered throttle is throttle, then Landing, it's airbrakes.

Aren't we clever?

The arrangement I had for eSoaring was to use both a switch and slider. In my case the slider was used to pre-set the power level I wanted to use for the prevailing conditions(calm, windy, distance, etc.) just before hand launching, with the switch used to activate the motor. Coupled to a soft start this worked well in competition. It also had the added attraction of acting as a motor cut-out safety switch when on the ground - although I appreciate that some may prefer a rotary switch with high-powered models as being even safer because it is less likely to get knocked by accident.

Dial forward a few years and I find this arrangement works well for slope flying, both scale and non-scale models. Leaving the slider at a default half-power position (or slightly more, depending on the particular model) and activating the motor by a soft-start on/off switch provides a quick and simple way of overcoming sink and getting back up to a suitable height. And of course, you're still free to increase the power using the slider once the climb is underway. Perhaps a little more complicated when used for ROG, but still workable I would have thought. I appreciate that you can re-purpose the throttle stick as part of flight conditions, but I've learned from long experience that when under pressure I'm less likely to make an error with simple systems. (Modern electronic chart plotters and instrumentation on yachts can be a nightmare from this perspective when unexpected problems always seem to arise in the middle of a very wet, dirty, rolly and windy night, just as you're in the middle of a crowded shipping channel, or at some other critical navigational juncture for example!)

Cheers, Brett