Fig. 4
From: An investigation of changes to commercial aircraft flight paths during volcanic eruptions
(A) Flight AZ1743 (ITA) – flight paths for 7 flights between Catania and Milan airports before heightened eruptive activity. (B) Flight AZ1743 which took place during the time period covered by VAAs (20:32 and 21:12 UTC) shown in blue. (C) Flight FR395 (Ryanair) – flight paths for 7 flights between Catania and Malta airports before heightened eruptive activity. (D) Flight FR395 which took place during a time period covered by an advisory (22:57 UTC shown in solid blue line). The aircraft momentarily entered the ash polygon but exited it in less than one minute by dropping in altitude