The United States Army Air Forces during World War II had numerous reconnaissance groups, key among them were:

1. 3rd Reconnaissance Group - This group conducted photo-reconnaissance missions in support of Allied forces in Europe.

2. 5th Reconnaissance Group - Known for its operations in the Mediterranean Theater, performing reconnaissance and mapping missions.

3. 7th Reconnaissance Group - Engaged in photo-reconnaissance and mapping operations, providing vital intelligence.

4. 8th Reconnaissance Squadron - Played a significant role in Pacific Theater operations, contributing to intelligence gathering.

5. 15th Strategic Reconnaissance Group - Specialized in long-range reconnaissance, often over enemy territories.

Beyond these, there were several more units with specific roles and responsibilities within different theaters of operations. The exact number of reconnaissance groups varies over the wartime period due to restructuring and reassignments, but these examples illustrate some of the critical reconnaissance units within the US Army Air Forces of that era.