This image was taken in 1943 during a Kōkūtai 802 patrol in the central Pacific. Note the paint wear on both machines. The 60kg bomb armament was standard for patrol flights against enemy surface vessels and submarines. Photo: ©Izawa
Text: Jan Bobek
Continued from issue 04/2023
In response to the Guadalcanal landing and lacking airfields between that island and the base at Rabaul, the IJN decided to establish a seaplane command in the area from August 28, 1942. It was given the name R-Hōmen Kōkū Butai (abbreviated R-Butai), R being the code name for Rabaul, i.e., R-Area Air Force. It was headed by Rear Admiral Takatsugu Jōjima, who had previously commanded several carriers, the last being Shōkaku. In late June 1942, he became commander of the 11th Seaplane Tender Division, which was the operational part of the newly formed R-Butai.
The seaplane tenders Chitose (with Pete and Jake planes), Sanyo Maru (Petes and Jakes), and Sanuki Maru (Petes) were the first ones under Jōjima's command. During September, they were joined by Kamikawa Maru (Rufes and Petes) and Kunikawa Maru (Petes). These units were tasked with defending the anchorages at Shortland and Rekata Bay off Guadalcanal. The Americans consistently attacked Rekata Bay, where the Japanese were trying to establish a base. Its supplies were provided by the seaplane tenders Akitsushima, Chitose and Nisshin. The seaplanes from R-Butai could not stay overnight in Rekata Bay for safety reasons, so crews flew to this location from Shortland in the early morning hours.
The Kamikawa Maru was completed as a cargo vessel in 1936. The Imperial Navy took her over in 1937 and completed her conversion to a seaplane tender two years later. After deployment in war against China she took part in campaigns in the Malay Peninsula, Borneo and Java. In May 1942, Kamikawa Maru participated in the Japanese landing at Tulagi, took part in Battle of the Coral Sea, and supported the landings in the Aleutians.
In August 1942, the Kamikawa Maru air unit was joined by a fighter Buntai with Rufe aircraft under the command of Lt. Jirō Ôno, who had commanded a seaplane unit aboard the cruiser Chikuma during the attack on Pearl Harbor. Commanding the Kamikawa Maru was Captain Torahachi Shinoda, who had held that position since September 1941. The primary mission of the Rufe pilots was base defense and reconnaissance. However, they also took on the role of ground attack aircraft during the fighting on Guadalcanal.
From the Shortland base near Bougainville, the Kamikawa Maru´s Rufe seaplanes operated from September 4, 1942, that very day their pilots already engaged a reconnaissance bomber B-17 and reported its damage.
Kamikawa Maru anchored off Amoy (Xiamen), China in July 1939, with a deck load of Kawanishi E7K and Nakajima E8N float planes. The Kamikawa Maru was completed in 1936 as an ocean liner but was converted to a seaplane tender a year later and was combat deployed in the aggression against China until the spring of 1941. At the start of the fighting in the Pacific, her air unit was equipped with E13A1 Jake and F1M2 Pete seaplanes. She was sunk by USS Scamp on May 29, 1943 approximately 250 miles north-west of Kavieng. Photo: Naval History and Heritage Command
The first victory was achieved by two pilots on September 13. The two Rufes piloted by CPO Jirō Kawai and W.O. Makio Kawamura took off from Rekata and were tasked with determining if Henderson airfield on Guadalcanal was back in Japanese hands. Although they did not spot Japanese forces at the base, they encountered a lone SBD Dauntless from VMSB-231. They managed to shoot it down and then attacked ground targets. Both Americans were killed, one of them, gunner Cpl. Horace B. Thomas who had survived the Battle of Midway at VMSB-241.
The tables turned the next day when, in the early morning hours, three Rufes under the command of Lt.(jg) Masashi Kawashima conducted another reconnaissance over Henderson Field. However, they encountered a force of seven Wildcats from VF-5 under the command of Lt. Cdr. Simpler. In combat, which ended low over the terrain, the high maneuverability and stability of the Rufe impressed American opponents. However all Japanese were shot down and killed. One of them was gunned while on a parachute by Wildcat pilot.
During the afternoon of the same day, twenty observation floatplanes escorted by two Rufe arrived at Guadalcanal. Their crews were tasked with attacking ground targets with 60kg bombs. The attack took place at dusk and was opposed by five Wildcats from VMF-224 and six machines from VF-5.
The Rufe seaplanes, piloted by Ôno and PO2c Matsutarō Ômura, clashed with Stover and Byler of VF-5. In a dogfight that included frontal attacks, Stover managed to shoot down Ômura. Ôno escaped the fight and claimed one of the Wildcats as downed.
The seaplane bases in Shortland area were attacked in the early hours of 5 October by Avengers and Wildcats from the USS Hornet (CV-8). There was very poor visibility over the target, and coincidentally two Petes from Sanuki Maru and two Rufes as their escort took off to join seven more floatplanes already patrolling. They were tasked to cover the destroyers Oyashio, Kuroshio and Hayashio on their voyage to Guadalcanal. In sudden defense of their own base, they were credited with shooting down five fighter planes.
An even more dramatic encounter occurred on October 10, 1942 during an attack on the Tokyo Express (a convoy of two light cruisers and four destroyers) including the light cruiser Tatsuta, on board of which was Lt.Gen. Hyakutake. Two Rufe seaplanes from Kamikawa Maru and two Pete biplanes from Sanuki Maru were deployed to cover them.
The Americans sent fifteen USMC Dauntlesses and six USMC Avengers against the vessels, accompanied by eight Airacobras and fifteen Wildcats.
Kamikawa Maru fighter planes on her cruise in the summer of 1942 during a transport to the Solomon Islands area. Of note on the YII-101 is the number on the front of the main float pylon and the convex cover on the top of the float, which covered part of the tank purge system located in the float. Photo: ©Izawa
The chunky gray-blue fighter planes of VMF-212, 223, and 224 were mistaken for bombers by the Japanese aviators, who attacked the group of “bombers” from above. The surprise of the Americans must have been no small one when they were attacked by two biplanes and two float Zeros, as the Rufe was then referred to by its enemies.
All the Japanese machines were shot down. A total of seven claims were made for the destruction of the two Pete aircraft, indicating the ferocity of the fight. While 2nd Lt. Gutt, Capt. Marvin and Maj. Smith of VMF-223 each claimed a Rufe shot down. They killed Seaman 1st Class Maruyama (in YII-107) and CPO Kawai (YII-104).
Two American aircraft were shot down by artillery fire from the decks of the ships, and the vessels were not hit. Maruyama and Kawai were among the most experienced seaplane pilots in the area. In September 1942, their aircraft were cited in a commendation by the Commander of the Combined Fleet.
The Kamikawa Maru’s fighter Buntai pilots scored 14 victories and had flown a total of 360 combat sorties in 211 missions by November 7, 1942. But nine of them were killed. After that date, remaining fighter planes and pilots were taken over by Kōkūtai 802.
Seaman 1st class, Takio Maruyama, aviation unit of seaplane tender Kamikawa Maru, Shortland, September 1942
c/n 15, Lt.(jg) Keizō Yamazaki, Kōkūtai 802, Shortland Island, February 1943
Kōkūtai 802, Faisi-Poporang base, Shortland Islands, February 1943
The fight for the Solomon Islands
In mid-October 1942, R-Butai was reinforced by nine Rufes under the command of Lieutenant Toshio Igarashi of the 14th Kōkūtai. Original unit with this designation was armed with Zeros and fought against the Chinese armed forces until the fall of 1940. In April 1942, the 14th Kōkūtai was newly created as seaplanes unit. From Rabaul it soon moved to Shortland and later even to Rekata.
The unit encountered B-17s on October 13 and on following two days, losing one of its officers in the process. It achieved its first victory on October 17 when four Rufes downed a Dauntless from VS-71. The unit had its first encounter with Wildcats on 30 October, when three Rufes from the 14th Kōkūtai and one Rufe from the Kamikawa Maru engaged US Marines with two SBDs from VMO-251 and six Wildcats from VMF-212 in an early morning raid on the Japanese base at Rekata. The Americans claimed three Float Zeros and two Float Biplanes as shot down, which was not far from the truth. In this combat Capt. Jack E. Conger scored his 9th and 10th victory. Two Pete machines from Sanyo Maru and one from Chitose were destroyed. The formation of four Rufes was led by 14. Kōkūtai´s Lt. Hideo Goto, but his machine was hit on takeoff and he managed to land later. The next Rufe to take off was not so lucky, with Teruo Watanabe of Kamikawa Maru perishing in the flames.
U.S. Marine Corps F4F-4 Wildcats of VMF-121 at Henderson Field, Guadalcanal at the end of 1942. Note centerline drop tank on the first F4F and the P-38F Lightnings in the background. Photo: U.S. Navy National Museum of Naval Aviation
In early November 1942, the 14th Kōkūtai was redesignated Kōkūtai 802 and its fighter Buntai was led by Lt. Hideo Goto. This officer, with four of his pilots, got into a large-scale fight on November 7 when, together with four Petes from Kamikawa Maru, they were tasked to provide cover for destroyers enroute to Guadalcanal. Dauntless crews were also headed toward these vessels, escorted by Wildcats from VMF-121, 112 and Airacobras from the 347th FG. In this engagement, Goto and his colleagues were shot down and none of them survived. One Pete also fell victim to the Americans, who lost one Dauntless and three Wildcats, including the machine piloted by the legendary Joe Foss, brought down by the rear gunner of a Pete biplane.
During December, the two remaining Rufe pilots of Kōkūtai 802 were still conducting patrols while preparations were underway in Japan to completely rebuild this unit. During turn of the year and the first half of February, their unit, facing frequent raids on Bougainville, began encountering Lightnings and Warhawks.
For instance,such a clash occurred on January 5, 1943, during the raid of five B-17 from the 26th BS escorted by six P-38 from the 339th FS, 347th FG under the command of Maj. John W. Mitchell. Their targets were Kahili airfield on Bougainville and the port of Tonolei. They were attacked by six Zeros from Kōkūtai 204, two Rufe aircraft from Kōkūtai 802, and several Pete biplanes.
Lt. Murray “Jim” Shubin of the 339th FS poses in front of his P-38G-13 (43-2242) on Guadalcanal. In all, he scored eleven certain victories and one probable victory. He was the only P-38 pilot to achieve five kills in a single combat flight in the Pacific. His unit frequently encountered Rufe fighter seaplanes from Kōkūtai 802 and did not always emerge victorious from the engagements, especially when engaged in maneuver combat. Shubin achieved his first victory on February 2, 1943 over Shortland in a dogfight with Rufe. In an attack from above, he shot down a machine of a PO2c Kiyoshi Akizuki, who bailed out from the burning seaplane. Photo: Fold3
At the controls of the floatplane fighters were PO1c Eiji Matsuyama and his wingman Superior Flyer Shinkichi Ôshima. Early in the fight, Matsuyama, in cooperation with one Pete seaplane crew, hit a P-38 piloted by 1st Lt. Ronald W. Hilken. Lt. Holmes and Lt. Norris tried to save him, but Hilken was last seen descending toward Vella Lavella Island. Matsuyama then attacked a Lightning piloted by 1st Lt. Wallace L. Dinne, Jr., igniting his left engine with cannon fire, the machine went into a spin and that pilot also remains missing.
In the encounter, Ôshima was shot down, bailed out and rescued by the crew of seaplane Pete of Sanyo Maru. He was apparently shot down by Maj. Mitchell, who was the only one to claim the Float Zero. This is the same Mitchell who would lead the strike group of four airmen, including the aforementionned Lt. Holmes, in the attack on the bomber of Adm. Yamamoto and its escort.
In mid-January 1943, 15 new Rufes and 15 pilots arrived at Shortland to reinforce the last remaining Rufe of the original unit. Reinforcements were under the command of Lt.(jg) Takeo Yokoyama, who had previously served as one of the officers of the Kamikawa Maru. His deputy was Lt.(jg) Keizō Yamazaki.
Kōkūtai 802 did not fare badly in these engagements. Their most notable success was their part in the so-called Valentine's Day Massacre. This was the name given to the February 14, 1943, by American airmen after the attack on vessels in the Buin and Shortland area.
F1M Pete aircraft from Kunikawa Maru and Rufe seaplanes at Poporang base in early 1943. Some Rufe aircraft had already received a coat of dark green paint on the upper surfaces. To the far right is Yamazaki's NI-118, note that it does not have the convex cover on the top of the main float that it apparently originally had. Photo: ©Izawa
Nine PB4Y-1 Liberator bombers from VB-101 flew to the target, escorted by ten P-38Gs from the 347th FG and twelve F4U Corsairs from VMF-124. Thanks to Japanese patrols on the islands between Bougainville and Guadalcanal, the Japanese naval fighters got airborne in time. Waiting for the attackers were 13 Zeros from Kōkūtai 204, 18 Zeros from Kōkūtai 252, and Yokoyama with 11 Rufes.
The Americans damaged two freighters but came under strong flak fire and faced attacks from well-prepared Japanese fighters. The Japanese lost only one Zero and two others were damaged. The Americans, however, lost two Liberators, four Lightnings and two Corsairs in fierce fighting. Yokoyama's unit claimed two bombers and one single-engine fighter.
The NI-118 was the fifth Rufe seaplane produced, so it was a rebuilt machine from the A6M2 Model 21 carrier fighter produced by Mitsubishi during its overhaul and rebuild by Nakajima. Pictured here in early 1943, after a year of service, this vintage aircraft shows considerable signs of paint wear. It is possible that the darker areas on the stabilizer are made up of reddish-brown primer. Foto: ©Izawa
Kōkūtai 802 pilots in the Shortland Islands during off-duty time. Photo: ©Izawa
One of the tents that were used to prepare for Kōkūtai 802's combat activities at Shortland. Photo: ©Izawa
To the coast of Australia
In mid-1942, the 36th Kōkūtai was formed in Balikpapan, Borneo. This unit was armed with Pete, Jake and Mavis seaplanes. In November 1942, its designation was changed to Kōkūtai 934, and in late February 1943 a fighter unit was formed. The unit operated first from Ambon and later from Maikoor, Indonesia. While defending its own bases, however, it also fought with four-engine B-24 Liberator bombers. Its primary task, apart from defending own bases, was patrolling against Allied vessels. Patrols usually consisted of one Jake and one Rufe aircraft as fighter escort. The area of operations extended as far as the north-west coast of Australia, so Japanese airmen would face not only Hudsons and Beaufighters, but also Spitfires.
Captured H8K Emily a A6M2-N Rufe seaplanes at Kwajalein Atoll in early 1944. Photo: US Naval History and Heritage Command
Leader of fighter unit of Kōkūtai 934, Lt. Toshiharu Ikeda, fought against Spitfires on August 10, 1943 while escorting the crew of E13A Jake which belonged to his parent unit. On the route of the patrol flight, they reached a point about 50 miles off the Australian coast. An Australian radar operator sent a pair of Spitfires from No. 452 Sqn RAAF against them, with F/O “Fred” Young and P/O “Bill” Coombes at the controls. Early in the engagement, the Japanese first surprised their opponents with the maneuverability of their machines. However, Young eventually managed to shoot down the Jake which crashed into the water in flames. Coombes attacked Ikeda, hitting his Rufe in the central float and fuselage. Although the float tank caught fire, Ikeda managed to return to base. He was not injured, but his machine sank on landing. After the fight, he claimed one Spitfire as shot down.
By the end of 1943 the unit had achieved 21 victories with the loss of four pilots. In early 1944 it also deployed new N1K Rex seaplanes in combat, but in March its fighter unit was disbanded.
A Rufe seaplane at an island base is strafed and set afire by PB4Y-1 Bomber of U.S. Navy Bombing Squadron 106, in the Solomons area, 1943. Photo: US Naval History and Heritage Command
Pacific and Japan
In March 1943, the fighter unit of the Kōkūtai 802 led by Lt.(jg) Yamazaki moved from Shortland to Jaluit Island in the Central Pacific. In October it was integrated into Kōkūtai 902 based on Truk Atoll. The base was often attacked by B-24s, but the massive raid (Operation Hailstone) by American carrier planes on Truk in the early hours of February 17, 1944, had fatal consequences. The Japanese radar operators considered the incoming formation to be their own bombers, and Japanese naval land-based and seaplane fighters only took off during the bombardment. The Japanese lost 81 aircraft on the ground and 31 were shot down. The American airmen were impressed by the raid as if it were a Hollywood movie. Kōkūtai 902 sent eight aircraft and claimed five victories. They clashed successively with Hellcat pilots from VF-5, 6, 9 and 10. However, four Japanese pilots were killed, and three others made emergency landings or parachuted. One of the pilots took off a second time, achieving one victory, but his machine was hit and had to make an emergency landing. In early March 1944, the fighter unit of Kōkūtai 902 was disbanded.
Part of the US enemy aircraft identification manual, dedicated to the Rufe. It was created using captured photographs. Photo: US Naval History and Heritage Command
Sasebo Kōkūtai performing patrol duties in Western Japan had its own Rufe unit. In May 1944, part of Sasebo Kōkūtai including Rufes led by Lt. Teijirō Yonemasu, moved to Chichijima Island for defense against the US Navy. They got into combat very early on July 4 and of nine Rufes, seven were shot down and four pilots were killed. Three victories, including two probables, were scored by the CPO Teruyuki Naoi. Their opponents were the night fighter Hellcats of VF(N)-76. Lt(jg) John William Dear, Jr. claimed three downed Rufes and Lt(jg) Fred LeRoy Dungan even four.
Towards the end of 1944, some airmen were transferred to land-based naval fighter units and the rest of the Sasebo Kōkūtai was incorporated into the anti-submarine Kōkūtai 951.
In Japan, Rufe aircraft served with several units tasked with training, and their assignments later expanded to include patrol operations. Training on Rufe seaplanes was usually a precursor to the more powerful N1K Rex fighter.
An image of the wreck of the seaplane Rufe from Kōkūtai 802 taken in 1944 at Emidj Island, Juluit Atoll, in the Marshall Islands. The reddish-brown base paint is visible on the aircraft. Photo: Jeffrey Ethell Collection
In April 1943, Sukumo Kōkūtai was formed, consisting of twelve fighter and twelve observation seaplanes. It used the base of the same name in Kochi Prefecture. In early 1944 its status changed to a combat unit, redesignated to Kōkūtai 453 and moved to Ibusuki Base in Kagoshima Prefecture. From February 20 it conducted anti-submarine patrols, but on that date its fighter section was disbanded.
Similarly, the Kashima Kōkūtai and Katori Kōkūtai training units were based in Chiba Prefecture. Their aircraft, including the Rufes, sporadically came into conflict with American aircraft.
Japanese seaplane base on Dublon Island under bombing attack on the first day of raids, February 17, 1944. Note bombs falling in lower center, and variety of Japanese planes in the water and on the ground at left. This was the base used by Rufe seaplans of Kōkūtai 902. Photo: US Naval History and Heritage Command
Among the pure training units that also used some Rufes was Kitaura Kōkūtai. In its case, several Rufe were reserved for instructors for the purpose of practice flights and maintaining skills in maneuver combat. One of them, CPO Tsuji, was killed in a dogfight with a Hellcat pilot on February 17, 1945.
One of the seaplane units that participated in Kamikaze missions at the end of the war was the training unit Takuma Kōkūtai. It was established in mid-1943 and its main armament was the E7K Alf and H8K Emily seaplanes. Rufe fighters are documented with this unit as early as 1943.
The Nakajima A6M2-N Rufe fighter seaplanes were already outperformed by their opponents at the time of their introduction into service. But like the A6M2 Zero Type 21, from which their design was based, the Rufe seaplanes remained in first-line service until the end of the war. Sadly, no complete example of this beautiful floatplane survives to this day.
F6F-3 Hellcat fighters landing on USS Enterprise (CV-6) after strikes on the Japanese base at Truk, 17-18 February 1944. Flight deck crewmen are folding planes' wings and guiding them forward to the parking area. Photo: US Naval History and Heritage Command
Kōkūtai 934 at Ambon Base used at least two machines with lightning bolt painting on the fuselage. Its design was different on both aircraft and was apparently painted white. While the seaplane with the lightning bolt and marking 934-116 is captured in several photographs at the shore or during taxiing, the second machine (in this photograph) is not photographed in a way that shows its tail code. In the past, it has been presented by some decal makers with, for example, the code 934-06, but this does not correspond to the marking system of the aircraft of this unit, which are captured in the newly discovered photographs. Photo: ©Izawa
Kōkūtai 802, Emidj Island, Jaluit Atoll, Marshall Islands, October 1943
Ensign Jin´ichirō Ozawa, Sasebo Kōkūtai, Sasebo Air Base, Japan, September 1944
Kōkūtai 934, Ambon island, Moluku Islands, March 1944
Takuma Kōkūtai, Takuma base, Japan, 1944
This aircraft was originally finished with grey paint on all surfaces. Later, at the unit, it was given a dark green paint job on the upper surfaces. By the time it was in service with Takuma Kōkūtai, the green paint was badly worn, with reddish-brown primer and metal surfaces visible in some areas. The stripe on the fuselage was probably the designation of the aircraft flown by leader of fighter unit. Takuma Kōkūtai was established in mid-1943 to train seaplane crews and it included a fighter unit with Rufe aircraft which was also tasked with training, including dogfight practicing. However, the command envisaged the eventual deployment of Rufe aircraft by this unit for the air defense of Japan. A photograph of a Rufe seaplane from the Takuma Kōkūtai exists, showing the mount of Ensign Kyoshi Suga armed with 30 kg bombs for use against B-29 bombers, but there is no evidence that such a combat deployment occurred. In 1945, part of the Takuma Kōkūtai was deployed on Kamikaze missions. Takuma Kōkūtai was disbanded at the end of the war.
Kashima Kōkūtai, Kashima base, Japan, 1944
This late production aircraft was finished in a factory applied dark green paint. Kashima Kōkūtai was established in 1938 as a training unit for seaplane crews. Her fighter unit, armed with Rufe floatplanes, was deployed several times to fight alongside Katori Kōkūtai airmen in the Home Defence and achieved several fighter and bomber kills. It was probably with this unit that the Hellcats of VBF-12 from USS Saratoga (CV-3) came into conflict around Kashima on February 16, 1945 and the Hellcats of VF-29 from USS Cabot (CVL-28) on March 18. In the first mentioned combat, the American fighters reported five Rufe kills and in the latter encounter claimed four victories. In May 1945, the Kashima Kōkūtai training section was cancelled, and a number of aircraft and crews were deployed on Kamikaze missions. Kashima Kōkūtai was disbanded at the end of the war.
I was kindly assisted in the preparation of this article by Messrs Yasuho Izawa, Ota Jírovec, Voytek Kubacki, Nick Millman, Noah Muranishi and the team at Scale Aviation magazine, Ryan Toews and Y. Yoshino. I would like to express my thanks for their support.
CLARINGBOULD, Michael J.: IJN Floatplanes in the South Pacific; Avonmore Books
FRANK, Richard B.: Guadalcanal, The Definitive Account of the Landmark Battle; Penguin Books
HATA, Ikuhiko, IZAWA, Yasuho, SHORES, Christopher: Japanese Naval Aces 1932 – 1945; Stackpole Books
HERDER, Brian L.: The Aleutians 1942 – 43; Osprey Publishing
KAWASAKI, Manabu: Nihon kaigun-no kanjōki to suijōki: Sono kaihatsu to senreki; Dai-Nippon Kaiga co.
LEWIS, Tom: The Empire Strikes South, Japan´s air war against northern Australia; Avonmore Books
LUNDSTROM, John B.: The First Team and the Guadalcanal Campaign, Naval Fighter Combat from August to November 1942; Naval Institute Press
Model Art 439: Heroes of the Imperial Japanese Navy Air Force in 1937 - 1945
MIKESH, Robert. C.: Zero – Combat & Development History of Japan´s Legendary Mitsubishi A6M Zero Fighter; Motorbooks International
MILLMAN, Nicholas: Combat Colours No. 9, An illustrated guide to the colour schemes and markings of the Mitsubishi Zero; Guideline Publications
SAKAIDA, Henry: Imperial Japanese Navy Aces 1937 – 1945; Osprey Publishing Ltd.
WATANABE, Yoji: Pictorial History of Air War over Japan, Japanese Navy Air Force; Gendaishi Shuppankai Co.