Flight Achmad Yani International Airport departs from Semarang Achmad Yani International Airport at 07:45 and arrives at Jakarta Soekarno–Hatta International Airport at 08:50.
The flighttime is about 1h 05m. The distance travelled ("as the bird flies"): 415 Km. So the average speed is roughly 383 Km.
The best day to arrive at Semarang is Saturday and it would be best to avoid Wednesday, as prices are on average 40.25% higher than on Saturday. (Average prices, based on 120028305 datapoints.)
We have a lot more statistics for flights QG 9799 and between Semarang and Jakarta.