My Biggest Frustration with ETHOS - Trims

 If there's one spot where ETHOS is truly limited, Trims are it.

The actual Trim configuration to use Trims as intended is just fine. In fact it's pretty good and given you can do custom trim steps, doing things like 3-position trim is actually pretty easy. From a pure trimming perspective the only things missing are Instant Trim (ie sticks to trim) and Trim to Subtrim.

The problem is that when you want to use rarely-used trims for anything else, ETHOS makes it VERY difficult.

There's a couple reasons for this.

The first is a shared issue with the pots. Only the Trimmers and Pots (S1/S2) have silkscreened labels on an X20. However NOWHERE in ETHOS are those labels ever used. You can at least rename the Pots in System->Hardware->Pots/Sliders Settings (and I have), but the T1-T4 labels for the trims are used exactly nowhere in the OS. That's just silly. The switches aren't labelled on the X20, but use standard naming while the trims and pots are labelled and don't use the labeled names.

I fly electric and sailplanes, so my Throttle trim is essentially never used. I don't really use rudder trim as a trim either (I always try and center the rudder with Subtrim).

That said, I have a number of use cases for those trimmers. For one, I'm getting sick of constant twiddling of S1 every time I switch models to get gain correct for my stabilizer. That will be the standard application of my throttle trimmer/T3 for now. Flap-Elevator mix adjust will be the sailplane equivalent. For the rudder, Aileron Differential Adjustment is the desired use case.

There is NO way in the canned surface mixes to disable trim. That means if you want trim disabled, you need to disable it in the Trim menu. When you do so, you can no longer get any movement from that trimmer, rendering it useless.

So what to do?

The short answer is I'm going to be replacing my Throttle canned mix with a pair of Free Mixes. Where needed, I'll do the same with Rudder so I can abuse the Rudder trimmer to control Aileron Differential et al.

For the Throttle mix.

The first is very simply mixing Throttle to the Throttle channel(s). Absolutely nothing fancy there.

For throttle cut however you have two options.

1. A 2-point curve added to the throttle mix with both points at -100, and triggered by your throttle cut position

2. A second Free Mix, with source Minimum, Active Condition of your Throttle cut position (or Flight Mode in my case) and type 'Lock'. Again, Output to your Throttle Channel(s). 

I use the second, as the Lock type is an override, nothing will activate throttle when that mix is active.

Now I can re-assign my gain channel input to the Throttle Trim (and argh, it should be Trims->T3)

The good news is that since Free Mixes can target multiple channels, you don't have to do a mixer pair for each channel in a multi-throttle setup.