I cannot place a wav in the timeline at the correct place

Hi,

Fairly new to After effects but I'm trying the old super hero landing bit and I've got the video sorted but am having troubles with the audio effects.

I have imported a sound while I'm flying into land but I want an explosion when I touch down.

I have a wav of an explosion but when I add it to my layer list, it plays from the start of the clip, while I'm in the air.

I can modify audio levels but I cannot place it at the timeline when I touch down.

I've also noticed that the sound while I'm flying is playing from the start of my footage but that is ok.

There must be a way to place a sound where you want it in the timeline.

Any help appreciated.

Greg