Q and E or slider to increase and decrease throttle. W, A, S, D to operate RCS. No sound for engine (yet).
The ΛL's main engine is an increased competence supersonic detonation ramjet that uses Coanda effect air inlets to operate at sub-optimal speeds and when stationary. It's RCS thrusters are hull-inset bell nozzles that, surprisingly, do not operate with monopropellant. Instead, they are rocket engines that feed off the ΛL's main LF+OX supply.