Moscow '41: Soviet Aviation and Strategic ToolsExpansion

From BoardGameGeek:

The Soviet Aviation and Strategic Tools expansion provides the Soviets with air capability and changes some game mechanics for air operations. Game mechanics are changed by adding the Defender Air Reaction Segment, inserting Air-to-Air combat, and changing the Anti-Air rule. The term “bomber” is replaced by “Air Units” to more accurately reflect the dual role (Air-to-Air and Airstrike) of participating Air Units. Except for the special German Elite Air Units (replaces the old “Stuka” nomenclature), the two Soviet Air HQ follow the same rules as the two German Air HQ. Thus, if in supply and not exhausted, the two Soviet Air HQ contribute to the total Logistical Value exactly as the two German Air HQ do. The Expansion rules update the base game rules for Air HQ, Air Units, and Air Combat. Part One provides minor updates and Part Two incorporates new rules. -description from the publisher