These airfields were intended for use by returning bombers suffering from low fuel and/or suspected damage to their pneumatic (wheel brake) and/or hydraulic (undercarriage) systems. All three airfields were equipped with one runway,  long and  wide. There was a further clear area of  at each end of the runway.
These airfields were intended for use by damaged bombers, equipped with a single long and wide runway, each with an additional designated area at the end.