Flight Amsterdam Airport Schiphol departs from Amsterdam Amsterdam Airport Schiphol at 20:50 and arrives at Madrid Adolfo Suárez Madrid–Barajas Airport at 23:25.
The flighttime is about 2h 35m. The distance travelled ("as the bird flies"): 1606 Km. So the average speed is roughly 622 Km.
The best day to arrive at Amsterdam is Tuesday and it would be best to avoid Saturday, as prices are on average 209.44% higher than on Tuesday. (Average prices, based on 440458 datapoints.)
We have a lot more statistics for flights KL 1509 and between Amsterdam and Madrid.