"Gen. McKenzie says he doesn't believe
#ISIS has the capability to take down an aircraft."
Just seen that - given the amount of MANPADS floating around with at least one Igla photographed in what seems to be ISIS hands (albeit nothing to say it was functional) and the number of "technicals" sporting ZU-23- I wouldn't be so sure (albeit a lot harder to use anti-aircraft guns against aircraft in these circumstances when DIY'd onto pickups, etc.).
Obviously once they'd climbed to altitude they'd be well out of reach of such weapons - but they have to get there first.