Skip to content

Tuning

Rotorflight's defaults are chosen to be safe and flyable on any properly set-up helicopter. Most helicopters hover and fly well on them -- but they're deliberately conservative, so with some tuning yours will feel more locked-in and precise.

Before you tune

Tuning only works on a helicopter that's set up correctly. Check first:

  • [ ] The mixer is calibrated: commanded blade angles match real ones. The defaults assume this.
  • [ ] The RPM filter is working, and a Blackbox log shows a clean gyro. Don't raise D on an unfiltered helicopter -- it will cook servos.
  • [ ] The headspeed is steady -- tune the governor first if it isn't.
  • [ ] No slop: worn ball links, a sticky tail pitch slider or a loose servo arm can't be tuned out, and make the helicopter wag or wobble whatever the gains.
  • [ ] Blackbox logging is on, so you can see what happened.

What "too high" looks like

Raise a gain until the helicopter starts to misbehave, then back off. How hard you test depends on how you fly:

You fly Test with
Sport Sharp stick taps; fast forward flight with a sudden stop; hard climb-outs
Aerobatics Flips and rolls with crisp stops; tic-tocs
3D Everything above, at full rates and collective; piro-flips; fast backwards flight

Fast wobbles (5-8 Hz -- a shudder) come from P or D too high. Slow oscillations (around 1 Hz -- a wallow) come from I too high, or P too low.

The order

Follow Tuning Process:

  1. Cyclic cross-coupling and collective-to-pitch compensation, while the gains are still soft and the effects are easy to see.
  2. Cyclic P, then D, then I.
  3. Cyclic F, then B if you want a sharper feel.
  4. The tail: P, D, I, then the stop gains and precompensation.
  5. High Speed Integral for fast forward flight.

Change one thing at a time, and keep notes. A profile per tune (Profile Switching) lets you compare two in the same flight.

Tools that help

  • Blackbox -- logs show what your eyes can't: whether I is doing the work F should, whether a stop overshoots, where the noise is. Open logs in the Blackbox Explorer.
  • Adjustments -- sweep a gain on a knob in flight, then read the value off afterwards.
  • The Lua suites -- change gains at the field between flights.
  • Tune Advisor (2.4, Ethos suite) -- the flight controller measures how the helicopter follows your sticks in rate flight; after each flight the radio combines your recent flights and suggests one change per axis -- for example F and rates when it turns faster or slower than asked, or I-term relax for bounce-back after stops. See Flight Tuning → Tune Advisor in the Ethos suite.
  • Presets -- complete tunes for popular helicopters, as a starting point.

The settings

Each setting is explained on the Profiles tab page, with a "Why these defaults" section and a symptom table.