Arriving at Northolt, the 315 replaced already famous 303 Squadron which was rested at Speke. The squadron's motor transport left for Northolt on Monday, July 14th. At the same time, part of the ground crew flew over in Handley Page Harrows. During the next two rainy days, the squadron organized itself completely and at new base. Some of the personnel was billeted at Cherry Lane School, few miles from the airfield.
Before 315 "Deblinski" joined the Wing's offensive missions, its pilots where "spread out" among more experienced 306 and 308 squadrons. This wasn't welcomed by 315 pilots, among whom many where already very experienced fighter pilots and who developed a strong feeling for their unit. First to guest fly was S/Ldr Pietraszkiewicz on July 20th and others followed. From 308, Deblinski inherited few Spitfire MkII, as for example P7855, ZF-B which became PK-K and P8387 ZF-U marked PK-H. Six Spits was ferried in from Tangmere, where they were worn out by the 616 Squadron. 

Right: Northolt. July 1941. F/Sgt Krieger's Spitfire after its oxygen installation blew up during a routine pre-flight checking. Krieger barely escaped with his life. He was a pilot with a bad luck and had quite few of mishaps on his account. Some eight month later he died in accident.

Franciszek Kornicki recalls:
    I flew my first mission over France on 23rd July 1941 as a guest of 308 Squadron by way of introduction to the shooting war. I was told to stick to my section leader come what may, keep my eyes open, watch my tail, my neighbors and the sky, not to do anything silly; they wouldn't like to lose me on my first flight.
We took off and met several other squadrons over a pre-arranged point and together with a handful of light bombers we flew to a target in the French coastal area - well over 100 of us. Fighter squadrons positioned themselves around the bombers and above, one lot on top of another. We were over 20K feet with France below us when I heard on RT that enemy a/c were approaching, and later there were reports of attacks and warning shouts - somebody was fighting somewhere. I thought we were moving about a bit nervously when I remembered the golden rule: never fly straight and level for any length of time - and so I too weaved behind me energetic leader, trying desperately not to collide with anybody and not to lose him. I managed, but I didn't see much else except him and my immediate neighbors. Our squadron was not molested and we all came back in one piece. I landed drenched with perspiration, jumped out of my a/c, lit a cigarette and inhaled deeply...

Northolt, Jul 1941. From left: Wolinski, Pietraszkiewicz, Czachowski, Mickiewicz (his back), Falkowski, Dr Jarosz, Tech. Officer Chrzanowski and Cwynar (with Mae West)

    By the end of August I had flown a dozen times over France, mostly as one of a large force comprising a number of fighter wings whose job it was to escort and protect often not more that six Blenheims - probably the lightest bombers in the RAF. They could not do much harm but they challenged the Germans and their escort thew down the gauntlet; come up and fight. And they did. There was a hell of a lot of Germans concentrated in packs along the coast from Amsterdam to Brest in 1941. We became best acquainted with the lot in St. Omer-Lille area and near Le Havre. Their a/c were better than ours. Me-109 was superior in climb, dive and armament, but a Spitfire could out-turn a Me-109 with ease at any time. Sometimes they would attack in packs from several directions, or nibble at the edges, or dive at terrific speed through the whole formation starting from above the top wing, down to Blenheims at 12K feet, firing at anything which might come in sight for a split second and away. It was all terribly fast, guns blazing all around, a/c turning, diving, climbing, in a series of individual dog-fights, people getting hurt, a/c being holed or exploding when hit by a big guns on the ground.
At other times our fighters would go out alone looking for trouble, free from the cumbersome task of protecting the bombers. A surprise attack by either side would result in losses to them or us.
    We flew twice on the 9th August and 315 Squadron had its first victory and first losses; it scored 2-3-3 of Me-109 but we lost F/O Czerniak and Sgt Niewiara. I knew Czerniak quite well, flew on his wing and thought highly of him. I felt his death deeply.
    I shall always remember a spectacular squadron take-off on 16th September, which ended in a disaster. We were spread over the airfield, all twelve a/c taking off from the grass simultaneously in a NE direction, with hangars and the Officers Mess on the left. Sgt Adamiak, being on the extreme left, was squeezed out of space and hit an Army post killing two men and wounding two, but he came out of it with hardly a scratch. I saw it happening and froze for a moment. Northolt wing, minus Adamiak, flew a fighter sweep around St. Omer again, where we met stiff opposition. In the ensuing engagement our squadron scored 3-1-1 for the loss of one of our pilots.