EMB170
The field elevation is within the GLEX perf charts, so no need for special engineering. BUT, we use Aero Performance Group runway analysis, who does produce a special departure procedure and a runway analysis for VQPR. The IFR weights are quite limiting, about 69,000 for the GLEX at ISA+10. You will need to do the research for your particular plane and planned arrival/departure and show to the Bhutan DGCA. Also, permits are limited, so plan well ahead. You will be required to work with Druk Air. It is all doable, if planned ahead.
GF