I heard the Chinese army airborne pilots crossed the treacherous Altaic Mountain with less problem as the Chinese authority themselves predicted.
The Russian originally seen the mountain crossing as a dangerous flight. But the Chinese pilots confidently insist to fly over because maybe, they had trained and flied their helicopter in an altitude higher than the Altaic Mountain can offer.
Another thing to highlight is the Chinese own ability to deliver their troops across the border despite the long hours of flight, plus the treacherous Central Asian weather. And whats more, this is their first time to do so.