Schedule a Burn

ctl/burn is for an impulsive maneuver: one UT plus a three-component CCI Δv. It is not a scalar “go prograde” number. Compute the vector in the parent body’s inertial frame, then let KSA orient and execute the maneuver.

/sim (in guest)

ut=$(cat /sim/time/ut)
t_ap=$(cat /sim/vessels/active/orbit/time_to_ap)
burn_ut=$(awk "BEGIN { print $ut + $t_ap }")

# Example shape only: replace 12 0 0 with your computed CCI delta-v in m/s.
echo "$burn_ut 12 0 0" > /sim/vessels/active/ctl/burn

HTTP (host)

# Same raw file value over HTTP.
curl -X POST --data '123456 12 0 0' \
  http://127.0.0.1:4242/v1/fs/vessels/active/ctl/burn

For circularisation, derive the required direction and magnitude with vis-viva, then express that direction in CCI. The currently prograde vector is not always CCI +X. Read position and velocity, do the frame math, then write the four numbers.

Solver phase

ctl/burn is solver-phase, so it takes effect on the next solver step. It is a planned maneuver, not a promise that a craft with no thrust or propellant can perform the impossible.

Next: React to events when a time is not the right trigger.

Next: React to eventsWait for a launch, flameout, dock, or separation without polling.