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Betaflight Launch Control: how to set up a repeatable race start

At a race start, most pilots either rest the quad on a launch pad or try to blip the pitch stick and the throttle at the same moment when the tone goes. Launch Control is Betaflight's answer to that. You arm, tip the quad forward onto its front arms with the throttle still at zero, let go of the sticks, and the flight controller holds that pose. When you push the throttle past a set point, the quad leaves at the same angle every time. When a reader asked Oscar Liang why not just tilt the quad by hand while armed, he answered that Launch Control is more precise, less hassle and gives the same angle every time.

Tue, 27 Oct 2026

The feature has been in Betaflight since 4.0, but the official guide and the current firmware no longer agree on one default. That detail decides whether your quad behaves the way the guide describes, so it is worth checking before the first try.

What happens while Launch Control is active

The Betaflight guide describes the sequence like this: enable the mode with a switch, arm, keep the throttle at minimum, push the pitch stick forward until the quad is at the angle you want, center the sticks and the quad holds the position. Advancing the throttle past the trigger point starts the launch, and from that moment the quad flies normally.

Reading the 2026.6.2 source code shows what the firmware does in the waiting phase:

  • The throttle is held at zero and air mode is treated as on, so the motors still produce the corrections needed to hold the pose.
  • The D term and feedforward are switched off, and the I term runs with its own gain (launch_control_gain) instead of your normal I gain. That is why the quad can lean on its arms without the I term winding up the way it normally would.
  • Your rates are ignored. Full stick deflection gives a fixed, slow tilt rate, so you can set the angle calmly.
  • When the throttle crosses the trigger, the I term is reset and normal flight takes over.

Which mode to choose

launch_control_mode has three values, and the guide pairs each with a type of quad:

  • NORMAL - for launching from the ground with a battery mounted underneath, where the quad balances on the battery and its front arms. Roll and pitch are held. You can still use yaw, but it is not held.
  • PITCHONLY - for race stands, or for quads with a top-mounted battery that sit on their front props when tilted. Roll and yaw are off and the front motors stay at idle. The guide warns not to use this mode when balancing on a battery: the quad will tip forward.
  • FULL - like NORMAL, but yaw is held too. The guide warns that yaw can wind up, and the firmware caps the yaw I term in this mode.

This is where the default matters. The guide lists NORMAL as the default, and Betaflight 4.5.2 shipped with NORMAL. In June 2024 a pull request titled "Move launch control default to pitchonly" was merged, and the 2025.12 and 2026.6 release lines default to PITCHONLY. If your quad stands on a bottom-mounted battery, runs 2025.12 or newer and you never touched this setting, it is in the mode the guide tells you not to use for that setup. Check it in the CLI:

get launch_control_mode

Setting it up

1. Make the mode reachable

In the Modes tab, assign a switch to LAUNCH CONTROL. The guide notes that the mode state is read at the moment of arming, so you have several ways to wire it:

  • a dedicated switch you flip before arming,
  • a momentary switch you hold while arming,
  • the same switch as arming, if you want it on every start,
  • always active.

Launch Control will not activate in a few situations listed by the guide and confirmed in the code:

  • you arm in any self-leveling mode (Angle, Horizon and so on), because it only works from acro,
  • MOTOR_STOP is on and air mode is off,
  • 3D mode is enabled,
  • you use stick arming instead of a switch.

2. Set the trigger and the hold strength

The four main settings are stored per PID profile, so a racing profile can have them while a freestyle profile does not.

Setting Range Default What it does
launch_trigger_throttle_percent 0-90 20 Throttle position that ends the hold. 0 uses min_check. Higher values make the launch more aggressive.
launch_control_gain 0-200 40 I gain used while holding.
launch_angle_limit 0-80 0 (off) Maximum forward pitch, in degrees. Needs the accelerometer.
launch_trigger_allow_reset ON/OFF ON Whether you can re-arm Launch Control after a launch without a power cycle.

For launch_control_gain, the guide's advice is practical: raise it if the quad cannot hold its position, and lower it if the motors speed up while the quad is sitting still. The guide also says to use the lowest value that works: some small movement and some sensitivity to wind are normal and not a reason to raise the gain.

launch_angle_limit does not move the quad to that angle. It only stops it from going further. In the code, the tilt slows down over the last 10 degrees, so the quad settles on the limit instead of overshooting. If the flight controller has no accelerometer enabled, the limit is ignored.

3. Decide how resets work

With launch_trigger_allow_reset = ON, you reset Launch Control after a launch by switching the mode off and on again while disarmed. With OFF, only a power cycle resets it. The guide recommends OFF if the mode is always active or tied to the arm switch, otherwise every re-arm during a race would put you back into the launch hold.

Before the trigger, you can arm and disarm as many times as you like. The guide gives the obvious example: the quad fell off its blocks, so you disarm, put it back and try again.

4. Check the arming angle

Betaflight refuses to arm when the quad is tilted further than the maximum arming angle (small_angle, "Maximum ARM Angle" on the Configuration tab). The default in 2026.6.2 is 25 degrees. If you arm on flat ground and only then tip the quad forward, this does not matter. If you re-arm when the quad is already leaning on its arms, it can block you. Oscar Liang's setup raises the angle to 180 degrees. Keep in mind that this also removes the check that stops you from arming a quad lying upside down or on its side.

5. Add the OSD warning

The OSD warnings element shows "LAUNCH" while the hold is active. With the accelerometer on, it adds the pitch angle, for example "LAUNCH 25". Since Betaflight 4.2 the warning blinks when the throttle comes within 10 percent of the trigger point, which tells you that you are about to go. In Configurator, enable the warnings element and tick "Launch control" in the list of warnings. Oscar's older CLI command set osd_warn_launch_control = ON does not exist in 2026.6.2, where warnings are stored as one bitmask (osd_warn_bitmask), so use the OSD tab instead.

You can also change all four settings from the goggles: PROFILE, then MISC PP, then LAUNCH CONTROL in the OSD menu.

A starting point from Oscar Liang

For a quad that launches from the ground on a bottom-mounted battery, Oscar's settings make a reasonable first test. He enables the accelerometer, sets the arming angle to 180 degrees, assigns a switch in the Modes tab and uses:

set launch_control_mode = NORMAL
set launch_trigger_allow_reset = ON
set launch_trigger_throttle_percent = 30
set launch_angle_limit = 30
save

These are his values, not a rule. A race stand needs PITCHONLY, and the angle that works depends on the quad and the course.

Safety

An armed quad resting on two arm tips is less stable than it looks. Oscar warns that the surface has to be solid and must not move, and that you should stand well away during takeoff. The Betaflight guide adds that you should treat the quad as ready to leap at any moment: keep your hands on the radio and be ready to disarm.

Practice the whole sequence with props off first. Watch the OSD warning appear, push the throttle up to the blinking point and confirm the warning disappears when you cross the trigger. Then do the first real launch in an open field, not on the start line.