Historic Spitfire Mk1/1a loadout

[Osprey]

In Al Deere's book "Nine Lives" he reports how pilots were crying out of De Wilde ammo but there wasn't enough. The Air Ministry said that incendiary tracer was just as effective in tests but pilots protested. I think their point was that they could see when they were hitting with De Wilde and the Air Ministry eventually relented. Either way, they were in very short supply of De Wilde until later in the BoB.