Cartoon-style bomb launch and distant explosion. Doppler shifting whistle starts at centre and pans to extreme right with fadeout. A muted detonation follows at extreme right - a non-realistic and short explosion. Created with ni fm8 running as a vsti inside flstudio 11 with a touch of fl reverb2. The "projectile" whistle is a soft square wave lightly modulated by a sinewave at 6x the frequency of the square wave fundamental to give it a touch of metallic ringing.
This is a small fragment of a human whistling in a special way, with tongue touching the top front teeth (leaving opening for air to flow), producing a sound that resembles a panflute.