Backwater to Frontline
Yap Island was a Backwater of the Pacific War save for a brief period when it became the center of opposition to the bombers of the recently formed Far East Air Force (FEAF) of the United States Army Air Force. On June 15th, 1944 the 5th and 13th Air Forces were joined under the FEAF Headquarters. On the same day U.S. troops stormed ashore at Saipan in a decisive turning point of the Pacific War. Strategically placed east of the Philippines between the Palau Islands and the Marianas, Yap assumed increased importance late in May 1944 when the Allies rapidly advanced westward in New Guinea and Yap became a transit point for Japanese air reinforcements. With the Allied invasion of the Marianas, Yap became a key base for launching attacks against Allied invasion forces. For a time in June and July 1944 it was the primary source of resistance to long range American bomber attacks in the central Pacific.
Movements to and Through Yap
On April 1, 1944 U.S. carrier planes raided Yap incidental to heavy raids conducted against targets in the Palau Islands. At Yap a nearly complete airfield was found under construction but with no planes yet present though there were plans to base some aircraft of the 26th Air Flotilla there when it was completed. A month latter there still were no planes at Yap but a Combined Fleet Operations Order (No. 76, 3 May 1944) projected that the main body of Air Group 265 (up to 54 fighters; a nominal figure, as on that date 265 was in transit with only 32 fighters mainly Zero model 21s) and some of the dive bombers of Air Group 523 (both units part of the 61st Air Flotilla) would be deployed to Yap before the last ten days of May. Yap was designated a dispersal base for other units including the fighters of Air Groups 261 and 263 and the night fighters of Air Group 321. Peleliu, the other Japanese base in the western Caroline Islands, was projected to have an air garrison of about 60 planes. As events turned out responsibility for Yap was shared between the 61st Air Flotilla and 22nd Air Flotilla.
On May 16, 1944 Admiral Michio Sumikawa, commander of the 22nd Air Flotilla at Truk, issued 2nd Air Attack Force (the operational title of his flotilla) Operation Order No. 12. This order specified the disposition of his forces and placed Air Groups (Kokutai, abbr. Ku) 202 and 503 at Yap. The order also stated that the main portion of the ground personnel of both groups would remain at Truk. Another operations order clearly suggested that the units might be recalled to Truk (or possibly moved elsewhere) under certain circumstances. On May 18, 41st Western Air Attack Force (operational title of the 61st Air Flotilla) Operations Order No. 1 was issued by Rear Admiral Keizo Ueno assigning the responsibility for the defense of Yap to Air Group 265. Toward the end of May half of Air Group 523 (Suisei ‘Judy’ dive bombers) was ordered to Yap.
Air Group 202 was a fighter group and Air Group 503 was a dive bomber group. As of the date of Sumikawa’s order the two fighter units (Sento-tai) of Air Group 202 (S301 and S603) had 28 operational Type Zero carrier fighters on Yap. Air Group 503 had 22 Suisei carrier bombers. The crew status report for Air Group 202 from a month earlier showed that none of the fighter pilots was rated “A” meaning suitable for all missions and usually signifying at least 1000 hours flying time. About half the pilots were rated “B” meaning suitable for most missions (400-1000 hours flying time). The remaining pilots included some who had completed a full training course but needed more experience (“C” rating) as well as others who had not completed operational training and even some who had not completed a full course in the training command. Air Group 265 had two pilots rated A, eight rated B, and 26 rated C. It was, however, on the date of the order assigning it to Yap still on Saipan and by the time it got to Yap it soon received orders to move south to Kau on Halmehera.
At this time the Japanese were preparing for a decisive engagement with American tasks forces and invasion fleets that were expected to follow-up their success in attacking Japan’s island bases and invading the Gilbert and Marshall Islands with moves that might include an invasion of the Marianas. While the Japanese carrier forces (1st Mobile Fleet, Admiral Ozawa) could not match the Americans carrier for carrier or plane for plane, it was planned that Japan’s land based air power (1st Air Fleet, Admiral Kakuta) flying from island bases would make up the difference in carrier air strength. Yap was 550 miles from Saipan (even closer to other islands in the Marianas) and well placed to play a role in such an engagement.
On May 27, 1944 American troops invaded Biak off the coast of western New Guinea. Previous plans had been to leave the defense of Biak to forces already in place there. Japanese strategic vision wavered. Ozawa’s carrier force was kept in waiting in the Philippines but at the beginning of June strong surface units were ordered to Biak carrying reinforcements (Operation KON). Since local land based air forces were weak, air support was provided from units at Yap and from the Marianas. As of May 29th a substantial part of Air Group 202 was en route south to take part in the Biak operations. Over a hundred Japanese fighters and bombers staged through Yap from the Marianas to bases in the Halmaheras and to Sorong. The Japanese suffered heavy losses during early June. In addition to transit and combat losses of crew and aircraft, some Japanese aircrews fell victim to tropical diseases. With the invasion of the Marianas, Operation KON was cancelled as quickly as it was inadvisably ordered.
Fighter detachments of Air Groups 202, 261 and 265 suffered particularly heavy losses and many of the aircraft at Yap in early June were apparently those unable to continue the trip to the south or damaged aircraft pulled back to Yap for repairs. The first Liberators over Yap were three Marine PB4Y-1Ps of VMD-254 on June 5th. They photographed Yap from 18,000 feet and observed about 30 fighters parked in rows and numerous other aircraft in revetments. Japanese figures for operational aircraft at Yap on June 5th were: 5 Zeros (202 and 261 Ku), 7 Suisei, 5 Gekko (night fighters), 2 Ginga fast twin-engine bombers, and three transports. Elements of Air Group 265 were also present but, at the time of the report, with no operational fighters (some fighters apparently arrived late that day). Just prior to the carrier strikes on Saipan, American intelligence credited Yap with 24 fighters, 6 dive bombers, 2 medium bombers and 6 night fighters.
The preliminary American carrier raids on the Marianas beginning June 11th inflicted heavy losses on the Japanese fighters and bombers there. American heavy bombers had been hitting Truk for months and on June 9th began attacks on Palau. A few days later raids on Yap commenced. American carrier planes had previously raided these targets, heavily hitting Truk twice and Palau once but doing only limited damage at Yap.
Battle of the Philippine Sea
From the middle of June Japanese fighters and bombers, many recently involved in Operation KON, carried out attacks against the invasion forces in the Marianas. They scored some success but failed to sink or disable a major warship. They had no affect at all on the great carrier Battle of the Philippine Sea or “Marianas Turkey Shoot.” Rarely did they even find the big carriers. An exception occurred on June 15th when attackers from Yap approached Task Groups 58.2 and 58.3 between Rota and Saipan in two waves late in the day. Three Suisei dive bombers escorted by 6 Zeros of Air Group 265 in the first wave were intercepted by eight Grumman F6F Hellcat fighters of VF-51.
The action started when one division of four Hellcats intercepted a twin-engine aircraft identified as a NICK (possibly a Gekko night fighter used as a guide or reconnaissance plane) and shot it down. Fifteen minutes later another division of Hellcats jumped six Japanese aircraft identified as TONY fighters but which must have been the Suiseis and part of their Zero escort. After the action started, two previously unseen fighters identified as HAMPS intervened. The Hellcat pilots claimed five TONYS and a HAMP destroyed. Only one Suisei and one Zero failed to return. The Zeros claimed a Hellcat but none was lost. This attack failed to get close to the carriers and the remaining planes eventually landed on Guam. A second wave made up of ten Gingas (from 521 Ku staging from Peleliu) led by Lt. Cdr. Takeshige Egusa and five Zeros approached at dusk. Two Gingas turned back early. The remaining aircraft were opposed by two F4U-2 Corsairs of VF (N)-101. The Corsairs had their hands full with the escorting Zeros and claimed only one bomber damaged and one fighter probably destroyed. The Zeros at medium altitude were later sighted by the ships and received some of the anti-aircraft fire.
The Gingas came in low and fast through the combined anti-aircraft fire of battleships, destroyers and aircraft carriers. Despite the hail of fire the speedy bombers were nearly within torpedo range before the first was seen to smoke and then careen into the sea. Fleet carrier Lexington was straddled by torpedoes whose “wakes…passed close aboard on each side” of the ship. Two other torpedoes also passed close to Lexington. Another torpedo passed so close to Enterprise “men in the overhanging 40-millimeter mounts had to lean out over their splinter shields to watch it.” Planes from Yap had come within a few yards of disabling or sinking two of America’s big carriers. All the bombers were lost. The attack had been so close and furious that the Americans suffered three killed and dozens wounded, as well as some structural damage to their ships from “friendly” fire.
On the 17th the largest of the raids mounted from Yap threw 31 Zeros, 17 Suiseis, and 2 Gingas against the landing area of Charan Kanoa setting LST-84 on fire. Later the attackers came across several escort carriers and despite interference from a total of 44 FM-2 Wildcat fighters pressed home attacks on several ships causing casualties and minor damage with near misses. Finally they hit escort carrier Fanshaw Bay with one bomb causing significant damage and several casualties. The following day carriers were sighted (actually only escort carriers) by Type 1 land attack bombers from Yap resulting in another big attack by Zeros, Gingas and other aircraft that damaged three fleet oilers, one seriously. Gingas were from Air Group 521 and Suiseis from Air Groups 503 and 523. Type 1 land attack bombers were from Air Group 761. Eight of the Zeros were from Air Group 201 (losing three but claiming two Hellcats destroyed). Others were from Air Groups 202 and 265.
Fighters arriving on Yap from mid-June included those from Air Group 265: six arrived on 14 June and others later, subsequently they went to Palau and from there used Yap as staging base for attacks on the Marianas. Twelve Zeros from Air Group 343 were ordered to Yap on June 17th but were returned to Palau by the end of the month. Remnants of Air Group 261 arrived by the middle of June. A few survivors of Air Group 202 also assembled on Yap. Many of these units suffered losses in sorties against the Marianas. Eleven Zeros from Air Group 201 (prior to reorganization) were at Yap for several days before returning to their base in the Philippines. Eight other Zeros from 201 Ku sortied from Yap and then operated from Guam for several days. Possibly there were stragglers from other units as well. Available Japanese records for this period are far from complete.
Heavy Bomber Raids
Dramatic carrier raids and the “Marianas Turkey Shoot” often obscure the role U.S. Army Air Force bombers played in the central Pacific campaign including the conquest of the Marianas. Although carrier task forces had devastated many important targets in the run up to the Marianas, Army heavy bombers had been keeping up a steady attack on Truk and other targets from bases in the Admiralty as well as from Eniwetok for months. In mid-June Yap became a key target for the B-24s of the 5th and 13th Air Forces. The 13th Air Force initiated the campaign on the night of 12-13 June but returned to day raids for most of its Yap campaign. The B-24s of the 5th Air Force also began their attacks on Yap with a night raid. The first 5th Air Force strike was largely abortive and a B-24 lost (B-24J No. 42-73197) on June 14th probably was not due to enemy action.
Within the newly created FEAF two heavy bomber groups of the 13th Air Force operated alongside of heavy bombers of the 5th Air Force (though administratively part of the 13th Air Force, they had previously been under the tactical control of the 5th Air Force as the 13th Air Task Force) and conducted operations against Yap from Los Negros in the Admiralty Islands. The 5th Air Force heavy bombers (90th Bombardment Group) remained very much a junior partner in the endeavor with few aircraft ever reaching Yap. Some of its bombers did hit Sorol Island and Palau in planned attacks or as secondary targets aborted from Yap. The 5th Air Force bombers were primarily concentrating on targets in New Guinea and islands to the west of New Guinea during this period. The 13th Air Force bombers sometimes struck these targets as well.
The 13th Air Force bombers opened the day campaign on June 22nd with 16 B-24s from the 5th Bombardment Group (BG) and 17 from the 307th BG. The Japanese were apparently caught by surprise not expecting a strike by unescorted land based bombers over so great a distance (over 1,000 statute miles). Japanese warships and cargo vessels were the primary target for this mission. None being found the secondary target, Yap’s airfield, was hit. Forty-four fighters, four twin-engine bombers and a dive bomber were photographed on the field (per Japanese reports there were 31 operational aircraft at Yap on the 20th) and 12 were assessed destroyed and eight badly damaged. One twin-engine bomber was observed engulfed in a bomb blast as it took off. The author has no Japanese sources to confirm these losses but it seems likely the Japanese suffered heavily. Two B-24s were damaged, hit by anti-aircraft (AA or flak) fire. One 90th BG B-24 also bombed Yap.
The next day 30 B-24s returned dropping 45 tons of bombs on the runway and dispersal area but met “aggressive” fighter resistance from a total 10 fighters variously identified as ZEKES (5), TOJOS (2), a HAMP, a TONY, and an OSCAR. Almost without doubt, they were all Zeros. A twin-engine aircraft also flew parallel to the bombers during the bomb run. The 307th got off with an attack from a single ZEKE but the 5th BG was subjected to attacks for 25 minutes. One B-24 (42-110139) had an engine hit and trailed smoke attracting the attention of several Japanese fighters. No. 139 eventually went down and other B-24s were damaged. Gunners claimed two Japanese fighters. The Japanese used six aerial bombs ineffectively and then gunnery attacks. Most, if not all, the intercepting fighters were from Air Group 201 present on Yap with ten pilots under Lt. Torajiro Haruta. Air Group 201 had two “airplanes seriously damaged from force landings” with one pilot seriously injured. This report most probably means the fighters were shot down and essentially verifies the American claims. ZEKE and HAMP were Allied codenames for the Type Zero fighter. TOJO, TONY, and OSCAR were codenames for Japanese army fighters, none of which was present on Yap. The Suisei dive bomber was not infrequently misidentified as the TONY fighter; a mistake made more understandable by the Suisei’s occasional use in interception operations (Air Group 503 had a secondary role to participate in such operations).
On the 24th nineteen 13th Air Force B-24s attacked Yap meeting opposition only from flak. The Japanese navy guard unit on Yap likely manned several 12.7cm and 8cm anti-aircraft guns. The Japanese army had four 75mm anti-aircraft guns on Yap. All these weapons could reach the B-24’s normal attack altitude. U.S. mission reports usually refer to Japanese anti-aircraft fire as “meager” and somewhat or generally inaccurate. Despite this several B-24s suffered damage from AA fire during the campaign.
On the 25th the 5th and 307th BGs each sent two squadrons of six B-24s from Los Negros against Yap Airfield. The 5th BG in the lead targeted the runway. The trailing 307th targeted the revetment area. Twenty-one bombers carried out the attack with abortive aircraft bombing Sorol Island. Bombing was conducted at 165 m.p.h. indicated airspeed or about 200 m.p.h. ground speed from about 12,000 feet. The 5th BG dropped mainly 1000-pound bombs to crater the runway. The 307th dropped 120-pound fragmentation clusters (six 20-pound fragmentation bombs per cluster). Most B-24s carried 30 clusters but a few carried only 20.
According to the mission report of the 307th BG “18 to 20 enemy fighters intercepted from 2 minutes before bombs away for 30 minutes. They consisted of Zekes with 1 Tony and 1 Tojo…About 20-25 passes were made at the formation, being pressed very eagerly – most from the 12 and 6 o’clock low positions. Every trick in the book was tried with two, three and four E/A [enemy aircraft] coordinated attacks developing from positions all around the clock.” Several ZEKES were described as having green fuselages but silver colored wing tips and rudders. The TOJO was possibly thought to be the new Raiden but positive identification was impossible (Raidens were scheduled to reach the central Pacific in June 1944 with Air Group 301 but were left in Japan when the group’s Zeros deployed to Iwo Jima; their presence on Yap cannot be verified and is highly unlikely). The 307th claimed three sure kills.
The 5th reported interception commencing just prior to the bomb run and lasting for 30 minutes. They identified their opposition as seven ZEKES (possibly also HAMPS), three TOJOS, and three TONYS. Most of these were reportedly mottled green and brown. The 5th BG claimed five certain kills.
Shortly after the bomb run B-24 #598 (44-40598) of the 307th BG was attacked by a Zero. The # 2 and 3 engines were hit and flames were seen coming from the cockpit and bombardier’s compartment. The big bomber was seen to perform a perfect loop and then fell off into a spin and crashed into the sea two miles south of Yap’s runway. No parachutes were seen and the entire crew was believed killed in the crash.
Another B-24 was heavily damaged and crash landed at base. Other B-24s suffered lesser damage. Returning bombers of both the 5th and 307th carried crewman with wounds inflicted by the fighter attacks.
Seventeen Zeros intercepted this mission. Four were from S301 of 202 Ku and these claimed a bomber destroyed plus two damaged. Air Group 201 was also involved but it is uncertain what other Zero units intercepted. Possibly Air Group 265 or 343 (both normally based on Palau) contributed as many as nine of the intercepting fighters. The S301 Zeros returned unscathed. Air Group 201 had one aircraft damaged in combat and two others damaged on the ground (bombers observed one plane burning on the ground). What damage or losses the other Zeros may have suffered is not known.
On the 26th the 307th targeted Yap’s runways with 1000-pound bombs (three per bomber) while the 5th BG targeted dispersal areas. Again each group attacked with two squadrons. The mission report of the 307th called the intercepting Japanese fighters the “first team.” The attacking fighters were noted as using tactics different from the high frontal attacks usually encountered in missions to Truk. In contrast some Japanese fighters attacked from below in steep climbing passes hanging on their props and apparently unaware of the B-24s’ effective ventral ball turrets. The report suggested the Japanese fighters might have taken off from Palau after being alerted by the Japanese radio station on Sorol Island. On the previous day nine Japanese fighters from Palau had transferred to Yap just before the B-24 attack tending to verify this observation. An estimated 25-30 fighters intercepted. Most were identified as ZEKES but a TOJO or Raiden was also reported. Seven B-24s were damaged but all returned to base. Three Japanese fighters were claimed by gunners. Air Group 201 had three fighters damaged in combat one of which was seriously damaged in landing. Losses among other Japanese units are not known.
On the 27th both 13th Air Force groups carried heavy bombs with targets for nineteen B-24s being installations in Yap town and the runway. An estimated fifteen to twenty fighters intercepted with seven B-24s being damaged in their attacks. Gunners claimed nine interceptors destroyed. Air Group 201 suffered damage to five of its aircraft (two of which were borrowed from Air Group 202). A Zero and a transport plane were destroyed on the ground. On the following day the B-24s were again opposed by 25-30 fighters. About 25 aerial burst bombs were launched in addition to conventional attacks. Eight B-24s were damaged. Four Zeros of Air Group 201 were hit during this combat.
After this raid the only additional attack until July 3rd was a small night raid which met no opposition. The U.S. submarine Albacore, fresh from playing an important role in the Battle of the Philippine Sea, was operating near Yap on June 29th when a Japanese plane carried out a strafing attack and punched holes in the submarine’s conning tower. The damage was not serious enough to terminate Albacore’s war patrol.
July 1944
As of the beginning of July the 1st Air Fleet, the “Decisive Battle Force”, that was supposed to play a key role in stemming the American advance across the Pacific had been reduced to 100 operational aircraft. Remnants of various units remained on Guam, Truk and at Palau. Japanese bombers, some flying from Yap, carried out desultory raids against American ships near the Marianas, evacuated stranded aircrews, and flew in vitally needed ammunition. At Yap a heterogeneous collection of fighters from various units provided the only substantial force of Japanese fighters capable of opposing American bomber raids against the Caroline or Mariana Islands. The remnants of Air Groups 201 and 265 (they had claimed only one B-24), as well as other units, were withdrawn early in July.
Bomber raids resumed on the 3rd of July when 23 B-24s were over Yap. Despite an interception lasting 45 minutes involving an estimated 15 Japanese fighters (identified as ZEKES, HAMPS and one unidentified) in which eight phosphorus bombs were ineffectively lobbed at the bombers, only four B-24s were damaged. Gunners claimed four Japanese fighters destroyed. A Japanese report claimed two bombers destroyed and ten damaged; one Japanese fighter was reportedly lost. On America’s Independence Day fifteen B-24s were subjected to a thirty minute interception by 15-20 ZEKES using high frontal passes. Some 25-30 aerial bombs were used. Only four bombers were slightly damaged. One ZEKE was claimed. A Japanese report mentioned no fighter victories but claimed six bombers shot down by anti-aircraft fire.
On July 5th two strike forces of twelve B-24s each flew against Yap. The first of these from the 307th BG shrank to eight bombers by the time it reached Yap. The eight B-24s were subjected to a 45 minute interception by about 30 fighters. Ten to twelve aerial bombs were dropped. In this interception there were many high frontal passes. One B-24 (B-24J No. 44-40611) received cannon hits in first one engine and then a second and went down. A second B-24 was crippled and crashed upon returning to its base. Two others were damaged. The second wave of eleven B-24s arrived a couple hours later and met only two fighters and were targets of two aerial bombs. None of the bombers were damaged. Twenty-eight Japanese Zeros opposed these attacks. One source states these were from 261 Ku. Most likely several units were involved.
Two dozen B-24s returned to Yap on the 6th and met only ten or so fighters that dropped aerial bombs within 100 yards of the bombers but then “failed to press the attack.” Yap town, the warehouse area, and radio station were heavily hit. A total of over sixty B-24s hit Yap on the 7th, 9th and 10th of July. They were generally opposed by an estimated 18-25 fighters. B-24 gunners claimed eight kills. Several B-24s were damaged. On the 12th 22 B-24s from the 5th BG were opposed by 15-20 fighters. Only one bomber was hit but one crewman was killed and another wounded.
The Japanese fighter force, already weak, suffered a further blow on July 8th. Six Zeros of Air Group 263 were transferring from the Marianas to Palau led by their experienced leader Lt. Yasuhiro Shigematsu when they were surprised by Grumman F6F Hellcats from VF-31 (CVL Cabot) near Yap and five were shot down. Only the ace Shoichi Sugita made it to Palau. While these fighters would have been a welcome addition to the fighter defenses of either Palau or Yap, their movement probably relates to general reorganization of fighter forces to be described later.
The attacks on Yap had become the exclusive province of the B-24s of the 13th Air Force. Their pattern of operations changed. Instead of sending squadrons from both the 5th and 307th BGs to Yap on the same day, the groups began to attack Yap on alternate days sometimes with a group committing all its squadrons on a strike. On the Japanese side the only change was the introduction of a new aerial bomb. In addition to the familiar 30kg Type 3 bomb that spewed out phosphorus fragments trailing spectacular white-blue streamers, the American bombers began to report projectiles that released small fragmentation bombs and burst with a billow of black smoke.
It is not entirely certain which bomb the Americans encountered. During 1943 the Japanese had developed three bombs of the type described. One weighed 250kg and was most probably not the type used by Zeros over Yap (Suiseis might have used this type bomb, however). The other two each weighed about 60kg and Zeros could carry two such bombs, one under each wing. One of these was also a less than likely candidate. The Type 21, No. 6 land bomb, model 5 ejected five 7kg small bombs but was primarily designed for use against aircraft on the ground. Most likely the B-24s encountered the Type 2, No. 6, Mark 21 bomb, model 1. This was designed for mid-air use and contained 40 small explosive canisters each with a 300g bursting charge.
The mission on July 13th was flown by the 307th BG; each of the four squadrons was to scheduled to participate with six B-24s. Take off was from Mokerang on Los Negros Island. The plan called for squadrons to bomb in trail with flights in javelin down formation within squadrons. The lead squadron (372nd) was to bomb from 13,900 feet with each succeeding squadron 300 feet lower. Squadron lead bombardiers were to sight for range and deflection while other bombardiers were to sight for range only. The target specified was defined in relationship to a causeway and certain roads. Bombing speed was to be 160 m.p.h. indicated. Bomb loads were seven 500-pound general purpose (GP) bombs for 15 aircraft, six 500-pound GP for eight aircraft, and ten 250-pound GP for one aircraft.
Twenty B-24s bombed Yap and four hit the secondary target, the radio station on Sorol Island. Japanese fighters were encountered about five minutes before the bomb run. The 10-15 fighters were identified as predominately HAMPS plus a TONY and a possible TOJO or Raiden and the remainder ZEKES. Frontal passes, both level and high, predominated but some high passes from 6 o’clock (rear) also occurred. These attacks downed one B-24 (B-24J No. 44-40609). Four others were holed by fighter attack, one slightly damaged by one of 30 aerial bombs employed, and two hit by AA fire. Gunners claimed five of the attacking fighters destroyed including one whose pilot was reported to have bailed out and others observed to crash into the sea.
For their part the Japanese claimed three B-24s shot down and reported two others were trailing smoke. The Japanese attack report radioed to their higher headquarters reported two fighters heavily damaged and three others that received hits. “Heavily damaged” in Japanese reports often connotes a total loss.
The 5th BG was over Yap the following day with 22 B-24s. Despite a thirty minute attack with fighters making passes from around the clock, only one B-24 was hit and one crewman injured by fighter attack. Another B-24 was damaged by flak. Astonishingly the official Japanese communiqué announced that intercepting Japanese fighters brought down eight enemy planes without loss to themselves.
Twenty-one B-24s of the 307th dropped 235 250-pound demolition bombs and twelve 500-pound demolition bombs on Yap from 13,500 to 14,700 feet on the 15th. They were met by an estimated 14 to 17 fighters, predominantly ZEKES, which intercepted “aggressively” for 35 minutes. During the fight S/Sgt. James M. Kendall was at his post as a waist ginner in B-24 # 567 when he observed a ZEKE in a firing pass from 2 o’clock high attack an adjacent flight of B-24s. Right after this attack Kendall observed B-24 # 119 (42-73119) to fall off to the left and come down on top of B-24 # 555 (42-73119). The collision caused an explosion and the wreckage of both planes fell into the sea. All 22 crewmen were deemed lost. A third B-24 (42-40857) was shot up and ditched about 240 miles north of Wakde Island. Two damaged B-24s landed at Wakde. One was so badly damaged it was left at Wakde when its crew returned to base. Other B-24s were damaged by fighter attacks and one bomber was damaged by an aerial bomb and one by flak. In the mission report the cause of the collision between the two B-24s was listed as “undetermined.” The Japanese communiqué reported that two U.S. bombers were downed and three damaged. Two Japanese fighters were lost, one listed as “crash dived into an enemy objective” and the other missing.
Final Battles
During July 1944 a major reorganization abolished most of the fighter Kokutai and Hikotai (air units) of the 1st Air Fleet. Many of the units that had fought over, or, passed through Yap, were gone including Air Groups 202, 261, 263, 265 and 343. In their place 201 Ku was enlarged and left as the only remaining fighter group. Within the group four fighter units, a fighter-bomber unit, and a reconnaissance/guide unit were created. Experienced pilots were in short supply and survivors in the central Pacific were sent to the Philippines to join the enlarged 201 Ku. One its four Sento-tai (S306) had been part of 201 Ku before the reorganization and was commanded by Lt. Haruta who had been at Yap for the first bomber attacks. The main body of S306 and Lt. Haruta had moved to Cebu in the Philippines. One buntai of S306 was created primarily from survivors of Air Groups 263 and 343 and assigned to defend Yap.
On July 16th buntai-cho Lt. (j.g.) Naoshi Kanno, formally took over the air defense of Yap with his newly activated squadron. After the reorganization, which officially occurred on July 10th, few experienced pilots remained on Yap. Kanno had graduated from the Naval Academy at Eta Jima and received his pilot’s wings in September 1943. After brief operational training he found himself in an operational theater and soon thereafter in a command position in Air Group 343. Most of Kanno’s pilots, whether from Air Group 263 or 343, had only graduated from an abbreviated pilot training course at the end of 1943 and had been sent to the Central Pacific with sketchy operational training in March 1944.
On the 16th 21 B-24s of the 5th BG braved murky weather to put about half their bombs in the intended target area. They were intercepted by ten fighters identified as seven ZEKES, a HAMP, an OSCAR and a Raiden. Although the mission report stated that fifteen aerial bombs were dropped “with considerable accuracy” only one bomber received minor damage from them. Gunnery passes were “not eager.” One bomber received 7.7mm and 20mm hits and had two crewmen wounded. Gunners claimed a probable and a damaged.
On the 18th the 5th Group returned with two squadrons bombing the dispersal area of the airfield and two squadrons bombing Yap town due to an overcast obscuring the airfield. The formation over Yap town encountered four ZEKES (one crew thought one was a Raiden) and two of these tossed aerial bombs from an arcing approach below the bombers. Two bombs exploded only 25 to 50 feet below one of the B-24s. Two B-24s flew through the white streamers without damage. The few gunnery passes that were made were described as “uneager” and came from the 9 or 11 o’clock low position. There was a different story for the other formation. It encountered seven ZEKES and though the lead squadron received only a few passes the trailing squadron received a number of aggressive passes from all directions including eight described as pressed to 50 yards. Two B-24s were damaged, one seriously. A gunner in 394th BS claimed a sure kill, the fighter seen to hit the water. Two probable kills and a damaged were also claimed. The Japanese communiqué claimed that three B-24s were downed.
Both the 5th and 307th BGs hit Yap on the 19th. Because of heavy weather half of 22 B-24s from the 307th aborted the mission. The eleven that got through found reasonable bombing conditions and, though clouds interfered with observation of the results, those bombs that could be observed struck the center of Yap’s runway. The formation met four fighters of which one crew identified one as a Raiden. The fighters tossed phosphorus bombs with “unusual accuracy” and each made one head on gunnery pass pressed to about 100 yards. Despite this no bombers were damaged. One ZEKE (reportedly with a green fuselage and orange wings) was claimed destroyed and observed by several gunners to crash in the ocean.
The B-24s of the 5th BG also encountered heavy weather and the sixteen that reached the target area did so in three separate formations. Each formation was attacked by at least five and as many as 8-10 enemy fighters. More than 20 aerial bombs were observed “dropped with unusual accuracy.” A total of 20-25 mainly “aggressive” passes were made, some steeply from above and others pressed to 200 yards. One ZEKE was claimed destroyed. B-24 # 594 flown by Capt. Longino, the formation leader, was seen to be hit and a fire was observed near the No. 2 engine. The Liberator (44-40594) made it 60 miles south of Yap before crashing. Ten parachutes were observed. Two other B-24s received minor damage from 7.7mm hits. The Japanese communiqué claimed that eighteen of 27 attacking B-24s were “heavily damaged” and that one Japanese plane was lost.
On July 20th fifteen B-24s of the 307th BG found the primary target obscured by clouds and bombed a secondary target based on observations of the outline of the island through the clouds. They were opposed by six fighters one of which was identified as a TONY. Attacks lasted 20 or so minutes and included phosphorus bombs and several frontal gunnery attacks from the level or slightly high position. The aircraft identified as a TONY was claimed shot down after it made what was reportedly its third head on pass. One ZEKE was claimed as a sure kill and one as a probable. Two B-24s were slightly damaged by aerial bombs.
Prior to the events on the 21st of July one is tempted to believe that Lt. (j.g.) Kanno urged his pilots to greater efforts to bring down B-24s. Saipan had fallen several days earlier and the other islands were threatened. A few Japanese planes continued to operate from Guam. Japanese bombers flew re-supply and liaison missions as well as some attack missions from Yap to support the Marianas campaign. As long as such actions continued Yap remained a key base that had to be defended. On July 21st the Americans invaded Guam. The Marianas campaign was reaching its climax. Perhaps Lt. (j.g.) Kanno recounted the gravity of the situation to his pilots on this day.
Twenty Liberators of the 5th BG challenged Kanno’s fighters on July 21st when they dropped 23 tons of bombs on Yap’s airfield. They were opposed by a reported dozen Japanese fighters of which some crews thought two were Raidens. The mission report stated most of the fighters were a mottled brown though one ZEKE was silver and one Raiden a vivid green. Some crews also thought that some aerial bombs were launched with the help of explosive charges. Many observations reported here and previously in this article (including “sure kills”; pilot bailing out, aircraft hitting the water) are simply not factual though honestly made. Perhaps such mistaken observations from the American side may provide context to the most famous incident of the Yap campaign as reported from the Japanese perspective.
After the initial aerial bomb attack the Japanese pilots began very aggressive attacks, mainly frontal approaches, on the tight American bomber formation during which they “dove into and through cones of fire thrown out by the bomber formation which they should have known were deadly. The Jap pilots saw their own fighters go down one after another and yet continued to press their attacks vigorously…” During these ferocious attacks Liberator gunners claimed no less than seven Japanese fighters destroyed. Upon return, the mission report recorded only two B-24s hit by 20mm fire, one in the vertical stabilizer and one in the rudder and two others hit by 7.7mm slugs. Though Japanese fighters are reported to have passed very close to the bombers, nothing in the report suggests anything as spectacular as an aerial collision occurred. However, an ordnance officer reported a very unusual eight-inch hole in the vertical stabilizer of one of the returning planes (presumably # 259 with the reported 20mm hit).
According to published Japanese accounts Kanno made two ineffective gunnery passes at the B-24s. On his third pass he came straight down the body of the bomber until his propeller gnawed off the rudder in a shattering crash. The impact caused Kanno to black out temporarily. When he regained consciousness he was in a tight spin and compressed into a corner of the cockpit. He responded automatically pushing the stick forward and applying rudder until he regained level flight. He watched the B-24 crash into the sea before returning his badly damaged fighter to base.
It is not certain that the Japanese account relates to this date but unless it does there is nothing as substantial as the unusual gash in the tail of a B-24 to connect it to American reports. Moreover, a Japanese fighter that passed close through the formation was seen with its engine seeming to be “tearing out of the mounting” as it went into a long curving dive. Perhaps this was Kanno’s Zero after his propeller sliced into the tail of a B-24, and though hardly noticed by the crew of the Liberator, left him temporarily unconscious with a disabled fighter. American reports state most Japanese attacks were head on and the Kanno account as recorded by the Japanese indicates his attack was as well. In such an attack the propeller may have struck the vertical fin but was unlikely to “gnaw” it. The closure rate would have been too great for more than a momentary contact, possibly leaving “an unusual gash.”
The fighter with its engine seemingly shaking “out of the mounting” was one of the seven the gunners claimed as kills. Known Japanese losses include Petty Officers Ryuji Tomita and Tetsuo Matsuo who were shot down and killed. This may have also been the action in which Petty Officer Tomokazu Kasai was shot down and ditched his fighter but was rescued.
There were two more raids over Yap that encountered interceptions. The 307th BG attacked with 22 bombers on the 22nd and had to contend with some aerial bombs and 15 or so “half-hearted” passes from 4 to 5 ZEKES. A couple B-24s were slightly damaged and a few ZEKES were claimed as probably destroyed or damaged. The following day 23 Liberators from the 5th BG faced eight interceptors including “a possible Val” and claimed two destroyed. Japanese fighters hit two B-24s and wounded three crewmen.
The final week of battles over Yap resulted in renown for Kanno and his unit. They claimed eight sure kills, nine uncertain victories, and 46 damaged. For these results and Kanno’s ramming “victory” the unit was awarded a commendation for valor. In fact they shot down only a single B-24. One other was seriously damaged and about ten others were damaged to a lesser extent. In return the buntai lost five pilots killed, two of whom were credited with ramming B-24s. Kanno’s buntai was withdrawn from Yap to reunite with its parent unit in the Philippines.
A few days later U.S. carrier planes raided Yap but found the Army heavy bombers had left few targets undamaged. Carrier planes conducted raids in September and again in October. There was no aerial opposition to these attacks. The attacks in October were a prelude to a planned invasion of Yap. Plans changed and Yap was left to rot on the vine.
As it became clear that the Marianas were irretrievably lost the Japanese scaled back their remaining air power in the central Pacific to build up the Philippines. In allocating the remaining air strength eight fighters were assigned to Palau but none to Yap. On August 2nd nineteen B-24s returned to Yap and claimed two aircraft destroyed on the ground. The twenty or so aircraft they sighted dispersed around the airfield were probably all unserviceable. There was no interception. Sporadic air raids continued but there were no more air battles over Yap. Yap returned to the Backwaters of the Pacific war.
This article was previously posted on PacificWrecks.com.