Brainstorming around that troubled nose. The A-1 models still suffered from the overheating of their BMW 801C-1 engine already identified in the prototypes and A-0’s. The operational life of those engines was quite limited; around 30/40 hours, at much. The A-2 with its modification to the exhaust system and added cooling slits later solved this serious teething problem. The rest is history.
One of the coolest, no pun intended, radial engine cowling affair.