Flight Changi Airport departs from Singapore Changi Airport at 10:50 and arrives at Kathmandu Tribhuvan International Airport at 13:25.
The flighttime is about 4h 35m. The distance travelled ("as the bird flies"): 2030 Km. So the average speed is roughly 443 Km.
There is an 2 hour time difference between Singapore and Kathmandu
The best day to arrive at Singapore is Wednesday and it would be best to avoid Monday, as prices are on average 230.52% higher than on Wednesday. (Average prices, based on 52599 datapoints.)
We have a lot more statistics for flights SQ 440 and between Singapore and Kathmandu.