Flight Kualanamu International Airport departs from Medan Kualanamu International Airport at 11:15 and arrives at Sibolga Ferdinand Lumban Tobing Airport at 12:30.
The flighttime is about 1h 15m. The distance travelled ("as the bird flies"): 72 Km. So the average speed is roughly 58 Km.
The best day to arrive at Medan is Monday and it would be best to avoid Sunday, as prices are on average 21.4% higher than on Monday. (Average prices, based on 278513 datapoints.)
We have a lot more statistics for flights IW 1258 and between Medan and Sibolga.