Issues while recording.

[Severum]

While I record with fraps, once an aircraft explodes I get a massive fps drop. I just went from 350+ to 18 when the plane exploded. Gfx are on medium high. I have a 570 GTX, 8 gig ram, i5 3.40ghz processor. So my computer is more than capable of handling the game. I'm just trying to figure out why that fps drop happens.