Flight Incheon International Airport departs from Seoul Incheon International Airport at 15:30 and arrives at Singapore Changi Airport at 21:25.
The flighttime is about 6h 55m. The distance travelled ("as the bird flies"): 2923 Km. So the average speed is roughly 423 Km.
There is an 1 hour time difference between Seoul and Singapore
The best day to arrive at Seoul is Monday and it would be best to avoid Thursday, as prices are on average 427.34% higher than on Monday. (Average prices, based on 690593 datapoints.)
We have a lot more statistics for flights TW 173 and between Seoul and Singapore.
