Flight King Khaled International Airport departs from Riyadh King Khaled International Airport at 09:00 and arrives at Ad Dammam King Fahd International Airport at 10:10.
The flighttime is about 1h 10m. The distance travelled ("as the bird flies"): 362 Km. So the average speed is roughly 310 Km.
The best day to arrive at Riyadh is Tuesday and it would be best to avoid Saturday, as prices are on average 221.5% higher than on Tuesday. (Average prices, based on 125647 datapoints.)
We have a lot more statistics for flights SV 1138 and between Riyadh and Ad Dammam.