Random thought on IJN aerial arm from late 1930s on:
- A trained pilot is worth it's weight in gold, an experienced pilot doubly so. It would be a prudent thing to protect these sacks of gold while they are in aircraft, and, in case they get downed but survive, the search and rescue service should be around, so start making one.
- Maneuverable but slow-ish fighter will have a harder time to kill enemy bombers when compared with a fast and well-armed fighter. The fast and well armed fighter will be able to catch enemy fighters.
- In order to have fast, well armed fighters with good protection, engines required will need all the help they can get. 850-1050 HP engines will not cut it, so inform Nakajima and Mitsubishi that the more powerful engines will be used on fighters, talk 1200 HP and more. So no mainstream use for the Sakae and Zuisei engine families, focus instead on Ha 41, Kasei and Kinsei.
- Don't allow to Aichi to buy the licence for DB 601A, have them make Japanese radials instead.
- No bespoke floatplanes where a 'normal' 2-seater with floats can be a solution.
- No bespoke recon aircraft, like the Gekko and Saiun, focus on making better fighters instead.
- No bespoke land-based fighters, aim to land base the carrier-capable fighters instead.