As Mr. Guggenheimer says, Sch is a nice Dutch letter combination that (apart from the Swiss) hardly any other foreigner can speak out properly. It is like the g in grr...(not the soft k in good) or the j in the Spanish 'jamon'. It was one of the ways Dutch soldiers tried to identify German parachutists in our unhappy 5 days stand against Germany in WWII, May 1940 - asking any unidentified stranger to pronounce 'Scheveningse schapen scheren' (shave sheep from Scheveningen). Or so. No way a German could pronounce this properly. The Dutch Schiphol = pronounced as Sgiphol, and any foreigner will make it Skiphol. Well possible that the FA used proper Dutch pronounciation in one announcement, and the English version in the second.