The heli should not explode when hit by a single missile, unless said missile hits a certain spot (e.g. the fuel tank). I believe it should explode when hit by two missiles at any spot.

How many missiles did you fire and what were you expecting?

1 missile and i was expecting it to explode in mid-air

Nope, not not happenin'.
/downvoted

You need to do some research on what missiles do to aircraft, the missile itself explodes but the aircraft does not. It damages sure, it can even rip off whole parts pending where it hits but the whole aircraft isn't going to blow up.

As an example, this helicopter was hit by an SA-7 http://www.mycity-military.com/imgs2/65178_256640505_AH-64_SA-7.jpg

Mass closing ancient tickets with no activity for > 12 months; assume fixed or too trivial.

If this issue is still relevant in current dev build, please re-post.