countAirAswShipType = (...shipTypes) => {
			return this.ship().reduce((count, ship) => {
				return count + (1 & (
					// Match with specific ship types
					shipTypes.includes(ship.master().api_stype) &&
					// Equip aircraft can ASW with air attack (TB/DB/Autogyro/PBY/SPB/SPR/LFB)
					// on any non zero slot
					ship.equipment().some(
						(g, i) => ship.slotSize(i) > 0 && g.isAswAircraft(false, true)
					)
				));
			}, 0);
		}
Estimate possible type of support expedition from current composition.
@return the same value defined by `api_support_flag`,
        1=Aerial Support, 2=Support Shelling, 3=Long Range Torpedo Attack, 4=Anti-Sub Support
        0=Unmet expedition prerequisite
@see http://kancolle.wikia.com/wiki/Expedition/Support_Expedition
@see http://wikiwiki.jp/kancolle/?%BB%D9%B1%E7%B4%CF%C2%E2