Flight Suvarnabhumi Airport departs from Bangkok Suvarnabhumi Airport at 09:00 and arrives at Koh Samui Samui International Airport at 10:35.
The flighttime is about 1h 35m. The distance travelled ("as the bird flies"): 113 Km. So the average speed is roughly 71 Km.
The best day to arrive at Bangkok is Tuesday and it would be best to avoid Sunday, as prices are on average 228.79% higher than on Tuesday. (Average prices, based on 5040202 datapoints.)
We have a lot more statistics for flights PG 119 and between Bangkok and Koh Samui.