Submarine logistics and unreliable reconnaissance

I-366 carried sixty tons of cargo, including aviation fuel, to support the reconnaissance detachment at Truk. The submarine carried Type 13 air-search and Type 22 surface-search radar. A defective shortwave antenna forced an early return for repair. On the renewed voyage, thirty-foot waves flooded the diesels and swept away deck cargo. Enemy air activity also delayed entry to Truk and unloading. The delivery supplied the material and fuel needed by the only flyable C6N, but its reconnaissance found Ulithi without carriers and the attack was postponed.