No. 263 Squadron was deployed to the area around Narvik, a strategically valuable port city in northern Norway then under German control, but fiercely contested by the Norwegians and Allies. Crossing the Norwegian Sea aboard the aircraft carrier HMS "Furious", the pilots took off on 21 May while at sea, in groups of three each led by a Fairey Swordfish of the Fleet Air Arm, and encountered thick mist around the island of Senja; the Swordfish and two Gladiators from one of the groups crashed into a mountain. Hull led the first four aircraft through and landed safely at Bardufoss airfield, about north-east of Narvik, at 04:20. A further 12 Gladiators followed four hours later. Fourteen Gladiators were operational and began flying patrols from Bardufoss on 22 May, carrying out 30 sorties on the first day. Hull and two other pilots together downed a He 111 over Salangen on 24 May 1940, killing two of the five German crew; the other three were captured by Norwegian troops after making an emergency landing at Fjordbotneidet. In all, during its two weeks of operations in northern Norway, No. 263 Squadron was to claim 26 confirmed kills and nine probable victories during 70 dogfights.