Tricky but manageable, steep descent gradient, high terrain, monsoon season till end of Oct... I have some files that may be of some value for you (Jepp charts for VTKN and some advisory info from Asian carrier operating heavy equipment - B777 there) but do not know how to attach the same to this message. If you know how I'll be more than happy to pass them to you.
And, yes, VNAV APP works fine till 5NM KTN VOR... Preferred landing RWY 02, T/O RWY 20... Low clouds around the MDA, RWY 02 uphill, 45m wide, use higher auto-brake setting, apply reversers, narrow taxiways, congested apron occasionally, and most airlines operate only day time, special engine out procedures to cope with high terrain and limited space, NAVAIDs work fine, reliable, good signal strength... HIALS, PAPI both sides of RWY...
Due high descent gradient you may need to use speed brake in combination with landing flaps... Configure for landing early, preferably pass NOPEN in landing configuration if you are approaching with heavy aircraft, passing 10NM FAP step descent, 70 expect 2000FPM descent rate …
Carry extra fuel to cover possible delays due WX... Alternates available are Dhaka (VGZR) and Calcutta (VECC) ...
Good luck!
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