Flight Incheon International Airport departs from Seoul Incheon International Airport at 08:20 and arrives at Hong Kong Hong Kong International Airport at 11:20.
The flighttime is about 4h 00m. The distance travelled ("as the bird flies"): 1621 Km. So the average speed is roughly 405 Km.
There is an 1 hour time difference between Seoul and Hong Kong
The best day to arrive at Seoul is Friday and it would be best to avoid Sunday, as prices are on average 38.42% higher than on Friday. (Average prices, based on 17896565 datapoints.)
We have a lot more statistics for flights GA 171 and between Seoul and Hong Kong.