Plane requirements

http://www.war2glory.co.uk/#

Scout plane:
Arms plant (lvl. 3)
Airport (lvl. 1)
Reconnaissance Techniques (lvl. 1)

Fighter: P-38
Arms plant (lvl. 7)
Airport (lvl. 4)
Firepower Technology (lv 7)
Fuel Engine Technology (lv 8)

Bomber:
Arms plant (lvl. 7)
Airport (lvl. 7)
Steelmaking Techniques (lvl. 7)
Fuel Engine Technology (lvl. 7)