After the First World War, a torpedo offers a useful attack option for an aircraft able to carry less than 2,000 pounds of weapons. The alternative is a small number of bombs, with uncertainty over both hitting the target and causing sufficient damage. This choice matters particularly to single-engine carrier aircraft, although land-based attackers face the same need to find ships. Searching consumes fuel and works against carrying the heaviest possible weapons load. Reconnaissance therefore remains the first step in a successful strike, and preventing discovery is itself an air-defence objective. Before radar, extending visual observation is one way to gain warning before an approaching aircraft becomes an immediate threat.
Chapter · 36:50-39:02
Torpedo-bomber payloads and the need to find the fleet
Interwar strike aircraft had to divide their capacity between useful weapons and the fuel needed to locate ships before attacking them.