How the PS-1 and US-1A handled rough seas

The PS-1 was the patrol and anti-submarine aircraft in Japan's earlier flying-boat family, while the US-1A performed air rescue. The performance figures given for that family include operation in seas with waves about three metres high and a takeoff run of 220 metres without wind, or 150 metres with wind, for roughly 36 tons of aircraft and load. Those runs were shorter than an Illustrious-class carrier's 225.6-metre length; even a short-bow Essex was longer at 870 feet. The anti-submarine PS-1 carried homing torpedoes, depth charges, and rockets. It could land on the water to use dipping sonar, although sonobuoys were preferred. The airframe needed for water operations added weight and reduced performance, giving conventional patrol aircraft advantages of their own. The development line discussed here reaches back to a first flight in 1967 and service entry in 1971, with the final US-1A retirement in 2017 as the US-2 took over.