Sunday, 20 April 2014

Coming soon, Thermal Duration / F3J setup for Taranis

It's good to know that a good few people are using my F3F setup, or something based on it, in their models. This has encouraged me to think further, and to perhaps build a family setups for other Fxx classes. The question is: what next?

A few pilots have requested variants for e-glider/F5J and Thermal Duration/F3J. As I have some experience of Open Thermal, and also didn't want to tackle a motor just yet, it's a TD/F3J version which is the subject for my second project.

F3J setup - flight modesadjusters and backlight

Major redesign

Things have changed out of all recognition since I last competed in a thermal event. So I've done a little research on the net. One article I can recommend if you're contemplating an F3J setup is this one by Joe Grini, on the Samba site.

Anyway, out of the fog, a specification has emerged. As always the emphasis is on usability and adjustability (for quick trimming). So:
  • Five flight modes 
  • Spoiler permanently enabled (except during launch)
  • Camber presets, but with manual over-ride for the thermal phase
  • Keep the tasty bits from the F3F setup i.e. calibration mode, and in-flight adjusters
The splendid Companion9X software allowed me to try out different approaches and evaluate them rapidly. I'm now pretty happy with the way it all hangs together, on the bench at least.

Here are some of the features:

Flight modes

The new setup has five flight modes: Launch, T1,T2 & T3, and Landing.

  • Launch mode is for steering the model up the line.
  • Once off the line, the active flight mode is T1, T2 or T3 depending on the position of the main flight mode switch. These correspond to thermal, cruise and speed flight respectively.
  • Landing mode is entered from any of the T- modes by pulling back on the throttle stick. The stick threshold is adjustable. 
Since Landing mode is a proper flight mode, settings for camber and trim are always consistent when landing irrespective of the previously active mode.

Camber control

Each flight mode has a base camber setting (or 'preset'). By default, Landing and T2 have zero camber, T1 and Launch have positive camber, and T3 has negative camber (reflex).

In T1 mode, a slider permits limited in-flight adjustment of the preset. The range of adjustment is 30% either side of the preset value.

The Launch preset is similarly adjustable, but via a knob. Again, the range of adjustment is +/- 30% either side of the preset. The pilot will typically adjust this before the flight according to the wind strength.

Finally, a snapflap mix is available. By default it's enabled in T3 (speed) mode only.


As with my F3F setup, the throttle trim has a dual function - in Landing mode it adjusts spoiler compensation, while in speed (T3)  mode it adjusts the amount of snapflap.

The rudder trim is used to adjust Aileron differential (diff settings are stored per flight mode). As you move the trim to the right, diff decreases and the aileron response increases.

[It's a pity the Taranis doesn't have extra trim levers. For example it would have been great to allow in-flight trimming of combi rudder. FrSky, if you're listening, please sprinkle some trimmer dust on the Horus!]


The consensus is that the sliders were pretty rough on early Taranis sets, and not really good enough for motor or camber control. To FrSky's credit, the sliders on recent sets are a lot better. They're also available as replacement parts (e.g. from T9). I would certainly recommend replacing the original sliders if they are to be used for anything remotely critical.

The next task is flight testing, and polishing up the instructions. In the mean time, I'm always open to suggestions.

Happy Easter flying!


Dan Neelands said...

Nice. I can't wait. I've hacked up your F3F program to do just this including turning on landing mode with the stick. I feel quite confident that your ground-up approach will be even slicker.


RC Soar said...

Thanks Dan. It shouldn't be long now.

Anonymous said...

Your F3F setup is awesome. But I fly thermal duration so I am REALLY anticipating your F3J setup, hopefully to be closely followed by a motorize setup for the ALES flyers. I'll be playing with the F3F setup for now but hurry......:-)

RC Soar said...

Unfortunately appalling weather has delayed flight testing, but I'm aiming for release by mid June.

Nigel Taylor said...

Hi Mike I was taught to fly gliders by a power instructor. I am now trying to convert to a full glider set up I have bought a Taranis as well as a JR 9X2. I fly a Radian Pro as well as Phil Brandreth's old converted Eclipse V. Do you have any advice on where to start? Your F3J set up will no doubt be ideal can't wait for it to arrive. Any advice will be really appreciated. Thx Nigel

RC Soar said...

Hi Nigel, pending the (fairly imminent) F3J setup, you might consider bench-testing the F3F setup on your new model. It would give you insight into what to expect as there are many similarities between the F3J and F3F setups. Hopefully you'd also find out which of your two tx's were more suited to you.