Flight Achmad Yani International Airport departs from Semarang Achmad Yani International Airport at 13:50 and arrives at Jakarta Halim Perdanakusuma International Airport at 15:00.
The flighttime is about 1h 10m. The distance travelled ("as the bird flies"): 389 Km. So the average speed is roughly 333 Km.
The best day to arrive at Semarang is Tuesday and it would be best to avoid Friday, as prices are on average 13.04% higher than on Tuesday. (Average prices, based on 44745606 datapoints.)
We have a lot more statistics for flights GA 239 and between Semarang and Jakarta.