Board Thread:Game Updates/@comment-3502824-20170920014601/@comment-1915363-20170930072949

@ Reikku Actually, you need only two New Model Aerial Armament Materials. The third one is for F6F-5N... when you already have F6F-3N that enables carrier NBCI, so you can wait out the future events for that.

If you have time and equipment slots to spare, you can invest on combat rations for extra screws. The Type 3 Active Sonar isn't particularly hard to craft, not to mention that you can just farm them off from Makigumo and Naganami if you have problem procuring them.