 The aircraft from 5 Group had practised a time and distance method for bombing; a distinctive point on the surface was used as a datum for the release of the bombs at a set timeand therefore distancefrom it.H2S radar worked best over contrasting areas of ground and open water and 5 Group was to fly an approach run from Cape Arkona on the island of Rügen, to Thiessow to check time and heading.From Thiessow to the islet of Rüden any adjustments were to be made, followed by a timed run to Peenemünde on Usedom.