Complex sentence: For a staff pilot, there would a think black line all around the aircraft.Some Day fighter units also used geometric patterns of alternating black and white horizontal stripes on the engine cowling, or using checkerboard patterns on the cowling.
Split into simpler sentences: For a staff pilot, there would be a thick black line all around the aircraft. Some day fighter units also used geometric patterns of alternating black and white horizontal stripes on the engine cowling, or checkerboard patterns on the cowling.