Flight Achmad Yani International Airport departs from Semarang Achmad Yani International Airport at 19:30 and arrives at Jakarta Soekarno–Hatta International Airport at 20:35.
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 month to arrive at Semarang is March and the most expensive month to fly is July. (Average prices, based on 2769 datapoints.)
We have a lot more statistics for flights CX 247 and between Semarang and Jakarta.