a stop at Fukuyama, Japan. On 6 June 1945, the submarines and aircraft began training for night air operations in preparation for a surprise Japanese air strike against the Panama Canal in which the submarines would launch ten M6A1 floatplanes, which were to strike the Gatun Locks from the east with six torpedoes and four bombs, emptying Gatun Lake and blocking the canal to shipping for months. During training, the Japanese demonstrated that four trained men could prepare one of the floatplanes for launch from a submarine in seven minutes and that each submarine could assemble, fuel, arm, and launch all three of the floatplanes it carried in 45 minutes. Despite various obstacles—the presence of mines and U.S. Navy submarines and shortages of aviation gasoline—the submarines and aircraft launched a number of simulated air strikes. While Submarine Division 1 was still at Nanao Bay, the expected imminent fall of Okinawa to U.S. forces and the increasing pace of air strikes by Allied aircraft carriers on the Japanese Home Islands prompted Japanese Imperial General Headquarters to cancel the Panama Canal strike on 12 June 1945 and decide instead to use the submarines and their floatplanes to strike the Allied fleet anchorage at Ulithi in the Caroline Islands. The submarines and aircraft completed their flight training on 19 June 1945, with all of the M6A1 floatplanes taking off from the waters of Nanao Bay that day. One failed to return, and the bodies of its two crewmen later washed ashore on Sadogashima. Operation Arashi At 13:25 on 25 June 1945, the Combined Fleet issued orders for the attack on Ulithi, dubbed Operation Arashi ("Mountain Storm"). The orders called for I-13 and I-14 to transport Nakajima C6N1 Saiun (Iridiscent Cloud"; Allied reporting name "Myrt") reconnaissance aircraft to Truk in the Caroline Islands in late July 1945. In Operation Hikari ("Shining Light"), the C6N aircraft were to conduct a reconnaissance of Ulithi, noting the presence and location of Allied aircraft carriers and troop transports. I-400 and I-401 then were to launch a combined total of six M6A1 floatplanes—which were to use the reconnaissance information to assist them in targeting Allied ships—on 17 August 1945 for a nighttime strike under a full moon against the Ulithi anchorage, each pilot receiving a hormone injection to improve his night vision and each plane armed with an bomb. After the strike, the aircraft were to land near the