Islands of Destiny: The Solomons Campaign and the Eclipse of the Rising Sun by John Prados

the Imperial Navy in their sights. A fierce battle ensued. U.S. intelligence initially exaggerated the results, including two heavy cruisers among assorted other victims. But Japanese losses were serious enough: four merchant vessels blasted, plus damage to light cruiser
Yubari
, the seaplane tender
Kiyokawa Maru
, and light damage to three destroyers and other merchantmen. Pilot Nemoto Kumesaka of the
Kiyokawa Maru
recorded this as “our biggest loss since the beginning of the war.” Captain Ban Masami’s
Yubari
had to repair at Truk, out of action for a month.
    Japan’s landings on New Guinea completed the agreed Outer South Seas offensive so far as the Japanese Army was concerned. Despite U.S. air attacks, General Horii Tomitaro’s South Seas Detachment regrouped at Rabaul, replaced on New Guinea by naval troops. But the Imperial Navy continued eyeing the Solomons, and began raids on Port Moresby. By mid-March it had moved a detachment of Zero fighters forward to Lae,where they flew counterair missions against Moresby. A unit of Type 1, or “Betty,” bombers followed. Lae also functioned as a recovery station for bombers damaged in the Moresby raids. On April 1 there were nearly a dozen Japanese aircraft at Lae—but ten more under repair. That day there were only twenty-four planes at Rabaul, all of them at Vunakanau field. JNAF aircraft photographed Port Moresby and, in the Solomons, the island of Bougainville.
    Allied air reconnaissance detected construction at Rabaul as early as March 9. At the end of that month the headquarters of Rear Admiral Yamada Sadatoshi’s 25th Air Flotilla arrived to take closer control of the several JNAF air groups now flying from Rabaul. Conditions were primitive. Only improvised officers’ clubs served the Japanese cadres. One of the several volcanoes surrounding the town had erupted in 1937, and others were semiactive. Rabaul was subject to debilitating vapors and rains of volcanic dust, especially in summer. Ash from Vulcan volcano mountain eroded aircraft fuselages at Vunakanau, and fumes from Tavurvur ate away at fabric wing surfaces at Lakunai, major headaches. Vunakanau had fifteen fighters and nine medium bombers. At Lakunai field on April 10 there were six Zero fighters but twenty-four under repair. A couple of days later an equal number landed from the aviation ship
Kasuga Maru.
They had to be modified for tropical service. Yamada also lacked crews, especially after the one-sided fight with the
Lexington.
The JNAF often maintained only a one-to-one ratio of crews to aircraft, low by the standards of many air forces, and tropical diseases took a toll as great as enemy action. More than a dozen fresh crews were called up from Japan and the East Indies to make up shortages. One section of the flotilla’s bomber group was still training in Japan and had to be called to the front.
    The fifty-year-old Admiral Yamada had never faced anything like this. He had been a flier for half his life and had skippered two aircraft carriers. In fact, Yamada was the only aviator of flag rank in the Imperial Navy. Not just the aviation headaches, but the South Pacific climate and New Britain volcanoes posed challenges. If not on the bridge of a flattop, Yamada would have been more comfortable on the streets of Paris, where he had been a naval attaché, or Tokyo, where he had served with NGS. A resourceful officer, Yamada devised ways to protect aircraft from the elements. The admiral began pressing for new fields farther from the volcanoes. Unfortunatelysurveyors did a poor job selecting the first site, Kerevat, where construction began in June. When completed, its drainage was so bad the field could not initially be used. Allied air attacks were rated as “probable” by the 25th Air Flotilla war diary for this period. As raids picked up, Yamada ordered revetments camouflaged. He established new patrol patterns for scout planes to warn of task forces, searching 600 miles out on several