Unit scale is left undefined in A&A. It seems to shift as the game progresses, as armies expand in the game. Another issue is quality. The large German starting force represents their superior quality, so German scale is somewhat different than the other nations. If you must have numbers, the starting point is John Ellis, World War Two, A Statistical Survey 978-0816029716 A posting by Imperious Leader has the following numbers Air: 200-250 Front line Fighters = 1 unit 200-250 Front line Fighter- Bombers= 1 unit 450-500 Front line Bombers= 1 unit