On 1 July, 141 Squadron despatched "L6997" on the first Defiant night patrol. In August, the squadron was operating both by day and night; on 15 August, the first possible nighttime success by a Defiant was recorded, and from September onwards, the squadron principally operated at night. In September, as a response to the commencement of heavy attacks upon London by the "Luftwaffe", known as "the Blitz", B Flight of No. 141 moved to RAF Biggin Hill, Bromley, while A Flight relocated to Gatwick Airport, West Sussex in October prior to moving to RAF Gravesend, Kent. Successful claimed interceptions took place, such as two He 111s being claimed on 15/16 September; the first confirmed kill by Defiant of the squadron was made on 22 December, of a single He 111.