In my experience it has always been near impossible for a FJ pilot to correctly V.ID a helo.
And even if you can get the 'type'....chances of being 100% sure its enemy is very slim indeed.
The "good-guys" in NATO operate Russian helos too.
Whilst the USAF did get a kill on a Mil-8 with a LGB in GW1, they also V.ID'd a pair of US Army Blackhawks as Russian Hinds and shot them down in Afganistan (circa 1990).
Its hard to imagine a situation where FJ assets would be used (read 'wasted') on air-to-air helo ops.
That only leaves the targets of opportunity.
a. an FJ heading in to his/her target isnt going to stop for tea with a helo
b. an FJ returning from a mission may have a crack (one pass) but, likewise, isnt going to stop and 'play'. ?One pass, good V.ID.....and a kill......?
Im not saying it wont ever happen but its very unlikely indeed.
All the above said....in ones hyperthetical world.... 1 v 1 the helo will live. 2 v 1, the helo should die.
Question: Would 5 helos make you an ace or just get you some gentle ribbing!!