Thursday, October 27, 2016

The ‘I-Go’ Operation

Admiral Isoroku Yamamoto, commander of Combined Fleet, transferred headquarters to Rabaul for Operation I-Go.

A2-2-152 was flown by a wingman of carrier Junyo.

2-1-202 was flown by a wingman of carrier Junyo. Solomon islands, during I-GO operation, April 1943. This plane shows two vertical red bands that means when Junyo was second carrier of 2nd division.
Beginning with the I-Go Operation in April 1943, photos indicate that the aircraft of either of the two carrier divisions assigned to temporary duty in the Solomon islands over painted both the A prefix in their tail codes and the fuselage vertical bands in some aircraft.

The Allies now possessed the initiative in New Guinea and among the Solomons. Their supremacy rested upon their air superiority, due not so much to the quality of material as to the tactics forced upon AirSols by the aggressive Japanese, whose losses in actual combat were far exceeded by the losses involved in all-weather flying at great ranges from their bases. While many American aviators were rescued, or were even able to regain their bases in damaged aircraft, damaged Japanese aircraft were less often able to return the 350 to 650 miles to Buin, Buka or Rabaul, and their chances of rescue after a forced landing were slim.

With the departure of the IJAAF fighters from Rabaul, only the IJNAF’s 11th Air Fleet remained to provide aircraft for the South-West Pacific area. The backbone of the force was made up by eighty-six A6Ms and seventy-two G4M ‘Bettys’, supported by lesser numbers of D3As and B5Ns. The Japanese Army had given up its offensive in New Guinea, but was now intending to stabilise a deteriorating situation by strengthening existing garrisons. At the same time, concern was felt about the American intentions out in the Solomons. To carry the necessary New Guinea movements and to check the Solomons build-up it was clear that temporary air superiority would have to be achieved over both areas. As the IJAAF Staff were intransigent over the matter of providing air units, the IJNAF would have to find aircraft from its own resources.

Only one source was immediately available. The Air Flotillas in the East Indies, Marianas and on Formosa had all had their most experienced personnel siphoned off for the 11th Air Fleet, and only the air groups of the First Carrier Division, Zuikaku, Shokaku and Zuiho, could provide a balanced reinforcement. The groups had been trained after the Battle of Santa Cruz and were only just attaining the level of expertise necessary to engage the American carriers, so that there was considerable opposition from the Combined Fleet (Admiral I. Yamamoto) and the Third Fleet (the operational carriers) commanded by Vice Admiral T. Ozawa, who had relieved Vice Admiral Nagumo in November 1942. The disaster in the Bismarck Sea forced the IJN to take the first fatal step at the end of March 1943, and by 1 April 161 A6Ms and D3As and a score of B5Ns had arrived at Rabaul, Buka, Ballale and Kahili. The dive-bombers and torpedo-bombers were on the Bougainville airfields to bring them within range of Guadalcanal, but the ‘Zeros’ had sufficient range to accompany the ‘Bettys’ all the way from Rabaul to the targets in New Guinea and the Solomons.

Operation PA, as the Solomons neutralisation was codenamed, started on 1 April 1943, with a sweep by fifty-eight A6Ms of the 11th Air Fleet. These aircraft were supposed to inflict maximum casualties upon any American fighters found airborne, but over the Russell Islands they were met by a mixed force of forty-one USMC F4F Wildcats, USAAF Lockheed P-38 Lightnings and USMC F4U-1 Corsairs, the last based at Henderson Field since mid-February. Only six of the defending fighters were lost, but Japanese losses from all causes amounted to eighteen, nearly a third of the force, while the returning pilots made extravagant claims.

The disembarked carrier aircraft were not ready for their first attack until 7 April, when eighty-nine fighters and forty-nine dive-bombers, reinforced by twenty-one fighters and eighteen dive-bombers of the 11th Air Fleet, rendezvoused over Kahili and made for Guadalcanal to attack shipping. The Japanese had chosen a good day for their strike, for there were some forty worthwhile targets in Lunga Roads. Coastwatchers gave ample warning of the approach of the raid, for three hours elapsed between the first report and the development of the attack, which was carried out in a series of waves.

Seventy-six American fighters intercepted, but of these only twenty went for the sixty-seven ‘Vals’, which, not surprisingly, broke through and attacked the ships. A Royal New Zealand Navy A/S trawler was sunk in Tulagi harbour, as were an oiler and a destroyer. The only other damage was to the hulk of a previous casualty, in use as a fuelling wharf. A dozen or so ‘Vals’ were shot down by fighters and the ships’ AA fire, as well as nine of the escorting A6Ms; the American fighters had claimed twenty-seven. The Japanese aircrew who returned overclaimed once again, to the extent that Admiral Yamamoto, who was directing the ‘I’ Operation, believed that the strike had achieved a major success, drawing the teeth of AirSols and weakening Allied merchant and warship potential for some while to come. In fact the fighters defending Lunga Roads had lost only seven of their number, and all but one of the pilots had been recovered.

With Guadalcanal neutralised to his satisfaction, Admiral Yamamoto switched his aircraft to the New Guinea combat zone. On 11, 12 and 14 April no fewer than 456 sorties were flown against Allied transports in Oro Bay, near Buna, and in Milne Bay, and against the Port Moresby airfields. These raids, four altogether, sank one ship and damaged five others: five USAAF and RAAF fighters were shot down, and the IJNAF lost eighteen aircraft. With air reports of a substantial victory, amounting to three warships and twenty-five transports sunk and many others damaged, and 175 Allied aircraft shot down, Admiral Yamamoto decided that the ‘I’ Operation had achieved its aim by 16 April, and it was terminated. A few days later the carrier air groups flew out to Truk, less the thirty aircraft lost during their five strikes. On 18 April, shortly before their departure, they had been standing by at Kahili awaiting a review by Admiral Yamamoto. The USN had learnt of this visit before the Japanese at Kahili, and with the USAAF achieved a masterpiece of intelligence gathering, planning and, literally, execution. Eighteeen P-38s of the 339th Fighter Squadron, USAAF, met Yamamoto’s ‘Betty’ and its escort a few miles short of Kahili and the chosen marksman, Captain Thomas Lanphier, destroyed not only the C-in-C’s aircraft, but also a second ‘Betty’ carrying members of his staff. The loss to the IJN was incalculable, for Admiral Yamamoto had been the only flag officer with experience and expertise enough to direct a holding campaign against the growing strength of the USN. Admiral M. Koga, his successor, was a competent commander, but he had had virtually no sea experience during the war so far, and as yet he was unable to command the respect which had been earned by Yamamoto. Morale was sagging, particularly in the Rabaul area, and his death occurred at an inopportune moment, with the Allies preparing for their next amphibious leap.

The use of CarDiv 1’s aircraft from shore bases had been moderately successful. The losses, some 15 per cent of the aircraft sent to the Solomons, had not been excessive in view of the results claimed. A precedent had been set for the use of carrier groups in land-based operations. The premises upon which subsequent deployments were based were false, and the Japanese carrier fleet’s effectiveness suffered accordingly.

New Georgia

On 17 May 1943 Admiral W. F. Halsey’s Third Fleet in the South-West Pacific was reinforced by the arrival of HMS Victorious and the battleship North Carolina. The carrier had been despatched from Pearl Harbor to join Saratoga in providing distant cover for the forthcoming invasion of New Georgia, a 160-mile leap forward from Guadalcanal, and one which was expected to be resisted bitterly by the enemy.

The Japanese had built airfields on New Georgia Island and Kolombangara Island towards the end of 1942, and IJNAF aircraft had been based there, to strike at Guadalcanal and to protect warships in the ‘Slot’. However, repeated attacks by AirSols had forced their withdrawal as a permanent force, and Munda and Vila airfields were used mainly for staging aircraft based at Rabaul, Buka and the Bougainville airfields. In April 1943, following the withdrawal of CarDiv 1’s aircraft, the IJAAF had been obliged to despatch more aircraft to the Solomons, about sixty in all, most of which were sent forward to Munda. Losses were made good to a very limited extent: replacements arrived at Truk in some numbers, but the extended flight from Truk to Rabaul led to some remarkable non-combat casualty statistics, particularly among the IJAAF aircrew. Up to April 1943 some 6 to 7 per cent of aircraft on ferry sorties failed to arrive, but thereafter the loss rate rose to about 25 per cent for IJNAF aircraft, and in June only two out of one flight of twenty-four IJAAF aircraft reached Rabaul.

At the beginning of June 1943 the IJNAF 11th Air Fleet and the IJAAF 4th Air Army possessed approximately 280 aircraft for operations, nearly 100 of which were G4Ms. On the 10th half-a-dozen of these ‘Bettys’ attacked a convoy bound for Guadalcanal to the southeast of the island. All important shipping movements to and from Guadalcanal had been accompanied by one or more of the escort carriers based on Noumea, and on this occasion Suwanee was in company. Good warning of the raid had been given by the coastwatchers, and the USMC Corsair patrols from Henderson Field shot down all six of the torpedo-bombers before they could close the CVE, their primary target. Aware of Allied interest in New Georgia, and that a major operation was forthcoming, the 11th Air Fleet made a determined attempt to destroy this convoy, first by a night torpedo attack on 10/11 June, and then at midday on 11th, as the ships were entering Lunga Roads. The night attack, by eighteen G4Ms, was evaded, the ships manouevring to force the aircraft to drop their torpedoes from unfavourable positions, and the day attack caused the loss of only one ship. Twenty-four bombers and up to seventy-two A6Ms took part in the daylight raid, and of the former only one returned to Rabaul. Further attacks during the month added nothing to the Allies’ casualty lists but cost the Japanese more aircraft than they could afford; 138 IJNAF aircraft were lost during the month, together with their crews. With a further forty IJAAF aircraft lost, and the high level of non-combat losses, further urgent reinforcements were required, over and above replacements.

For the second time the only source of reserve strength was the carrier fleet, the Third Fleet, and CarDiv 2 was selected to provide their air groups. Less well trained than those of CarDiv 1, they would still be superior to the inexperienced crews arriving as normal replacements. The move was delayed by the torpedoing of Hiyo, hit by one torpedo from the submarine Trigger during the night of 10/11 June. The attack took place fairly close to Yokosuka, a major naval dockyard, so that the problems of immediate salvage and repair were much simplified for the Japanese. Junyo and Ryuho had to embark Hiyo’s aircraft for delivery to Truk, and the short delay which was thus occasioned prevented the 150 A6Ms, D3As and B5Ns from arriving at Rabaul until the invasion of New Georgia was well under way.

For Operation Toenail, the New Georgia landings, Admiral Halsey’s naval forces included three CVEs and two fast carriers. These were to take no direct part in the assault, for with 258 fighters and fighter-bombers and 193 SBDs and TBFs AirSols had sufficient aircraft to provide fighter cover for the transports and the beach-heads, as well as close support and strikes on pre-briefed targets. In point of fact, the distance between the target area and the Russell Islands, the nearest fighter bases, was rather too great (175 miles) and imposed great strain on the pilots. A thirty-two-strong fighter patrol was programmed for daylight hours, for which ninety-six aircraft would be required out of the serviceable total of 213. Losses would reduce the pool required for strike escort and local defence tasks from Guadalcanal to New Georgia. Saratoga and Victorious possessed seventy-two F4F-4s and Martlet IVs (F4F-4Bs) between them, and there were another three dozen aboard the escort carriers. With deductions for self-defence the carriers could have provided another fifty to sixty aircraft for short periods, provided that they themselves were not attacked. The USN had no illusions of complete naval/air superiority, however, in spite of the enemy’s huge losses in June, and the carriers were held back, the fast carriers in company with three fast battleships to cover against an attempt by their Japanese opposite numbers against the invasion shipping. Sangamon, Suwanee and Chenango, with two old battleships, formed a reserve force whose main task was the protection of shipping between Espiritu Santo and Guadalcanal, but which could also fight a delaying action against a Japanese force attempting to break into the Coral Sea by the improbable eastern approach route.

The first landings on New Georgia took place at the eastern end of the island on 21 June 1943. Segi Point was unoccupied by the enemy, and work started on a fighter strip at the end of the month. By 11 July it was ready for emergency operations. No support, other than that of the destroyer-transports which had put the Marines ashore, was provided at Segi Point, and Task Group 36.3, the heavy covering force, did not sail from Noumea until 27 June.

Victorious and Saratoga had exercised together during the earlier part of the month, and, after assessing the particular tactical virtues of the Royal Navy carrier, Rear Admiral D. C. Ramsey, flying his flag in Saratoga, proposed a partial exchange of aircraft between the two ships. Victorious ability to operate the TBF-1 was marginal, in spite of recent modification at Pearl Harbor, but her fighter direction organisation was far superior to that of Saratoga. The advantages of each carrier being responsible for a single task were obvious, so all the TBFs of 832 Squadron were transferred to Saratoga, and twenty-four F4F-4s of the latter’s VF-3 joined the thirty-six Martlets of 882, 896 and 898 Squadrons aboard Victorious. The American carrier retained twelve Wildcats for strike escort and her own selfdefence. Planning, briefing and tactical co-ordination were thus much simplified, and the arrangement whereby one carrier was tasked with defence and the other with search and strike was near to the ideal. How effective the pair might have been in combat was never established, for although TG 36.3 remained at sea for 28 days during Toenail, the circumstances for its direct involvement did not arise.

Landings were made on Rendova Island and two small islands to the east of Munda on 30 June, the first assault on New Georgia Island itself being made on 2 July. Not until mid-afternoon on the first day did 11th Air Fleet aircraft press home an attack, when two dozen G4Ms attacked the transports in the Rendova anchorage, sinking the amphibious headquarters ship McCawley at the cost of all the aircraft which took part. An hour later a similar number of D3As appeared from Kahili, but these concentrated their attentions on the hulk of the HQ ship, scored no hits and lost heavily. Although A6Ms and a few IJAAF aircraft made hit-and-run attacks, these too achieved little at considerable cost.

The pattern was repeated on the next day (1 July), but after losing over sixty aircraft in the two days the Japanese were obliged to slacken their air effort until sufficient aircraft could be made serviceable for another onslaught. By the end of July the IJNAF had lost over 300 aircraft, in combat and through operational causes, during the ‘Munda campaign’.

The IJN faced another Guadalcanal-type problem. Supplies and reinforcements had to be brought from Rabaul and Bougainville in the face of strong Allied opposition, but without a carrier fleet strong enough to challenge the USN’s the scale of the earlier ‘Tokyo Express’ could not be repeated, even if the IJN had possessed sufficient destroyers for use as transports, and the heavy cruisers to cover them. Nevertheless, Japanese destroyers and landing barges did make a number of runs from Shortland Islands to New Georgia and Kolombangara, succeeding in passing undetected on the first occasion, but encountering opposition on four subsequent occasions. The Battles of Kula Gulf (6 July), Kolombangara (13 July), Vella Gulf (6/7 August) and Vella Lavella (17-18 August) in many ways repeated the pattern of battles around Savo Island during the last four months of 1942, with the Japanese destroyer torpedo’s long range inflicting casualties on opposing radar-equipped cruiser groups. The USN and RNZN, with considerable advantages in detection, communications and gunnery, lost one cruiser outright and another three badly damaged, as well as one destroyer sunk, while the Japanese lost an old light cruiser and four destroyers. Most of the troops carried were landed at or near their intended destinations.

AirSols attacked the Buin-Kahili-Shortlands assembly area for the reinforcement runs, TBFs and SBDs being supported by USAAF B-17s, B-24s and B-25s. Air support in the Munda area was provided by the naval and USMC attack aircraft, as many as 105 TBFs and SBDs taking part in a single raid. Strong fighter escorts were provided for the 130 strikes delivered during the five-week campaign, with up to 114 Corsairs, Wildcats, Lightnings and Curtiss P-40 Warhawks at a time to swamp the intercepting ‘Zeros’. Many Japanese warships and transport craft were damaged, including the heavy cruiser Kumano, and four destroyers and the seaplane carrier Nisshin were sunk by the strikes.

The CVEs covered their convoys without incident. The 11th Air Fleet was sufficiently occupied with events closer to Rabaul, and such submarines as were in the Solomons were being used as transports or to attempt the disruption of shipping around New Georgia. The covering position of TG 36.3 was 360 miles to the south of Guadalcanal (550 miles to the south of Munda at the western limit of the patrol line), but six sweeps were made to the north to within 250 miles of New Georgia. These pushes were preceded by TBF and SBD searches out to 230 miles from the carriers, and it was during one such sortie that the Task Group made its only contact with the enemy, an SBD of VB-3 sighting and attacking a G4M 60 miles to the northwest of the ships. The covering force returned to Noumea on 25 July. The Munda airfield had not yet been captured, but the beach-head was secure and it was clear that the main strength of the Japanese fleet was not going to be committed to the campaign.

The operations off New Georgia were the last extended carrier deployment during the Solomons campaign. Once the airfields at Segi Point and Munda had been developed, Rabaul was within comfortable fighter and dive-bomber range of AirSols. The US Fifth Air Force in New Guinea and Australia was already attacking in strength with its heavy and medium bombers. Japanese air and shipping losses continued to mount, and although the arrival of CarDiv 2’s 150 aircraft brought a temporary stiffening to the 11th Air Fleet in mid-August, this was counterbalanced by the complete withdrawal of the IJAAF component in the area. The occupation of Vella Lavella Island, between the New Georgia group and Bougainville, at the beginning of September provoked strong reaction from the 11th Air Fleet, as a result of which the Buin-based CarDiv 2 air groups suffered heavily and were forced to withdraw to Rabaul to re-form. During the same month Allied troops landed at Lae and Finschafen in New Guinea, and the remaining Japanese air effort had to be divided between the two fronts, with consequent heavy attrition. By early October 1943 it was clear that the last IJNAF reserves would have to be committed if the steady advance on Rabaul was to be checked, let alone stopped. CarDiv 2, Junyo and Ryuho, had been unable to train new air groups as they had been almost continuously engaged in ferrying replacement aircraft from the Home Islands to Truk since sending their own to Rabaul in early August, so CarDiv 1 was obliged to give up its trained crews for the second time in eight months. The IJN could have hardly chosen a less appropriate moment to emasculate its carrier force.

Friday, August 12, 2016

Japanese Army Air Force - China 1942

During early 1942, the enemy gradually strengthened its air forces in south China, especially around Hengyang and K'weilin. Also, aerial pictures taken by the 1st Air Brigade in late March showed that the runways on Chuhsien, Lishui and Yushan airfields had been increased from 700 meters to 1,500 meters; that ammunition and fuel were gradually being accumulated and that additional installations were being built. Furthermore, an airfield had been constructed at Chienou. This work was carried out under the protection of fighters that flew almost daily from Hengyang and Kweilin.

In early April, the 1st Air Brigade (using about 50 planes, including fighters and reconnaissance planes) attacked and destroyed a newly built enemy airfield in the Chekiang sector, destroying the runways and the majority of installations. Although the Brigade repeated these attacks again and again, each time the enemy succeeded in rebuilding the field.

Imperial General Headquarters foreseeing that airfields in the Chekiang area could be used to advantage by the enemy as terminals in raids against Japan from air bases and carriers in the Pacific, as well as from other bases on continental China, ordered the China Expeditionary Army to destroy enemy air bases in the Chekiang area.

On 16 April, Imperial General Headquarters drafted an operation-al plan, an extract from which read:

Objective: The primary mission will be to defeat the enemy in the Chekiang area and to destroy the air bases from which the enemy might conduct aerial raids on the Japanese Homeland.

It further stated that the new enemy airfields and their attach-ed installations were being skilfully camouflaged and decentralized and that they should be sought out and destroyed. On 20 April, a further directive was issued stating:

The Air Forces of the United States, Britain and China will seek bases in China from which to bomb Japan. They may also attempt to carryout air raids on Japan from Midway, Morell, the Aleutians and from aircraft carriers, in which event the logical terminal would be airfields in Chekiang Province.

Air and ground units will be employed to capture and secure airfields in the vicinity of Lishui, Chuhsien and Yushan. Other airstrips in Chekiang Province will be neutralized by our air units at an opportune time.

Consideration will be given as to whether certain air bases, together with the accompanying military installations and important lines of communication, will be destroyed completely or whether they will be occupied for a certain period of time.

In order to reinforce the 1st Air Brigade during its attacks against the airfields in Chekiang Province, in early April the Southern Army was directed to send the 62d Air Regiment (28 heavy bombers)and the 90th Air Regiment (20 light bombers) to central China.

On 30 April, Imperial General Headquarters ordered the Chekiang-Kiangsi Operation to be undertaken at the earliest possible date. The operation proceeded smoothly with the 1st Air Brigade cooperating with the ground units when required. Not only did the Brigade sup-port the ground forces by bombing the opposing forces but its reconnaissance planes greatly assisted the operation by supplying information in regard to enemy ground movements, positions and strength.

Subsequent to the occupation of the captured areas, by mid-August units of the 13th Army had destroyed the Yushan, Chuhsien and Lishui airfields. The enemy, however, continued to reinforce their air force around Hengyang and Kweilin and, with the withdrawal of the Eleventh and Thirteenth Armies, it was feared that using air-fields in Kiangsi and western Chekiang Provinces as staging areas, they would bomb the Homeland. The 1st Air Brigade, therefore, in spite of the fact that its fighting strength was gradually diminishing, repeatedly attacked and damaged airfields in this area.

Degraded Performance of the Japanese Navy Air Force (JNAF)

Pacific Glory, by Nicolas Trudgian (P-38 Lightning vs Mitsubishi Zero)
By 16 June photographs showed that aircraft at Rabaul had increased to 245; the subsidiary ‘ring’ airfields were also full of planes. There followed the single largest air battle of the entire Solomon Islands Campaign; 120 Japanese aircraft went up against 104 defenders in a dogfight over Savo Island, Tulagi and Cape Esperance. The Allies scored a remarkable one-sided victory with 49 Zeros and 32 dive-bombers, 81 planes in aggregate, downed for the loss of just 6 aircraft. While the Japanese were still able to commit large forces to the battle, the victory on 16 June continued the pattern of an increasingly one-sided battle for air supremacy. From April to early June 1943 the ratio of the Allies’ kills-to-losses averaged about 3:1; on 12 June the Allies scored a 5:1 victory and ten days later the win ratio jumped yet again to 13:1. What was happening?

A 3:1 win:loss ratio for the Allies was already a substantial advantage that spoke volumes about the advances made by Allied equipment as well as the quality of their pilots in the first half of 1943. By comparison at the start of the war Japanese Naval and Military Air Forces had overwhelmed the Allies throughout the Asia-Pacific Region, often winning air battles by ratios of 10:1 or more. In the first half of 1943 the Commander of Air Forces in the Solomons (COMAIRSOL) had already achieved a startling turnaround in performance. From the middle of June 1943 there was another huge leg up in comparative performance of Allied fighter forces. As with Lieutenant-General Kenney’s remarkable victory at the Battle of the Bismarck Sea, it seems that a number of disparate factors had led to a tipping point moment. The gradual erosion of the Guadalcanal Campaign was putting increasing pressure, not so much on the availability of aircraft, but on the availability of trained pilots. It was systematic of the entire structure of the Imperial Japanese General Staff that war was planned as a short-term project with the emphasis on attack. The Japanese Navy, even more than the Imperial Japanese Army, was particularly unprepared for a war of attrition; their psychology, inherited from their great victory at the Battle of Tsushima, was to focus energy and resources on the winning of a single transformative engagement rather than planning for a long war.

The Japanese Navy was not only failing to train enough pilots, it was also failing to protect them. It is instructive to consider that very few US pilots died when their planes were shot down. In part it was because, unlike their Japanese counterparts, US fighters had better armored cockpits. Moreover without self-sealing fuel lines, Japanese Zero frequently blew up when hit by tracer bullets, killing the pilot instantly. When US pilots ditched or parachuted into the sea, the US Navy had a well-organized search and recovery capability. The Japanese Navy did not. Advantageously most of the dogfights in the April–June 1943 period took place closer to US held areas. US pilots were also better conditioned, with rotation and rest and recreation (R&R) built into the whole logistic framework of the various forces operating under COMAIRSOL.

New Japanese fighters also had to face a multiplicity of challenges given the diversity in capability of the six types of Allied fighter planes with which they were likely to engage. By contrast US pilots in the South Pacific only had to develop tactics to combat the Zero. On 28 March 1944, the US Flight Test Engineering Branch concluded after testing a captured Mitsubishi Zero, “The airplane is highly maneuverable, has a fair rate of climb, and good visibility; however, its speed in level flight is low, it is lightly armed, has no armor protection for the pilot, and the fuel tanks are not self sealing. The cockpit layout is fair, leg-room is insufficient for an average sized man …” The Zero had abundant good qualities; it was reliable, had an extraordinarily long range, and was, above all, maneuverable and easy to fly. Even with the swathe of more advanced US fighters now arriving in the South Pacific, it was not wise to get into a prolonged dogfight with a Zero.

Nonetheless, Allied pilots learned to exploit the Zero’s weaknesses. Allied fighters with a superior ‘ceiling’ capability would look to swoop down on a Zero and then skedaddle before the enemy fighter could make his better maneuverability count. By shooting and then diving, US pilots realized that their Japanese counterparts could not follow because of poorer diving speeds. Moreover by working in teams US pilots learned to thwart the Zero’s superior maneuverability in dogfights.

In Tokyo the developing catastrophe in the air was being hidden from senior commanders. Although losses were heavy, Japanese crews were reporting massively inflated results for transport ships sunk and enemy ‘kills’. On 14 April 1943 Yamamoto ordered a two-pronged force, codenamed Y-1 and Y-2, consisting of 75 fighters and 23 dive-bombers from the Third Fleet (Y-1) along with the 11th Air Fleet’s 54 fighters and 44 medium bombers (Y-2), to make a major attack on Milne Bay, which had become an important logistical center for the Allied advance in New Guinea and the Solomons.

Japanese pilots claimed to have shot down forty-four Allied aircraft. In fact Allied losses amounted to a single P-40 and its pilot killed; four others were shot up and a P-38 crash-landed. Similarly exaggerated claims were made for ships sunk. Supposedly four transports had been sunk and six others heavily damaged. The reality was that only one ship was heavily damaged out of the three that received hits. Admiral Ugaki noted happily in his diary, “Today’s operations of Y-1 and Y-2 a great success. Congratulations! But at the same time our losses gradually increased too. This was natural.” On this occasion the loss of eight Japanese aircraft was far from a disaster but the action reports of Japanese crews were far from ‘natural.’ Ultimately the gross misinformation provided by both Army and Navy aircrews prevented their commanders from taking realistic action to change tactics, attempt to upgrade equipment and training, or take other measures to improve results.

Japan’s senior commanders were not the only ones deluded in the performance of their aircrews. The Naval General Staff, after briefing Emperor Hirohito on the superb performance of Operations Y-1 and Y-2, sent Admiral Ugaki a message from His Majesty with the pleasing words then recorded in his diary, “… convey my satisfaction to the Commander in Chief, Combined Fleet, and tell him to enlarge the war result more than ever.”

By October 1943 it had become clear that the air battle over the Solomon Islands was taking its toll on the Japanese Navy Air Force (JNAF). An American intelligence report written in that month noted that Japanese pilots made glaring tactical mistakes, unnecessarily exposed themselves to gunfire, got separated and lost mutual support, and at times seemed to be completely bewildered. Both bomber and fighter pilots ceased to display the aggressiveness that marked their earlier combat. Bombers ceased to penetrate to their targets in the face of heavy fire, as they had formerly done; they jettisoned bombs, attacked outlying destroyers, gave up attempts on massed transports in the center of a formation. Fighters broke off their attacks on Allied heavy and medium bombers before getting within effective range, and often showed a marked distaste for close-in contest with Allied fighters.

Some Japanese officers were also becoming aware of deficiencies in the performance of the JNAF. Commander Ryosuke Nomura, who took over the role of air operations officer at Rabaul in 1943, became acutely aware of a decline in pilots performance. He attributed this to America’s better aircraft, an inability to sustain a high level of maintenance of their own equipment, and a decline in the experience and quality of available pilots. By the beginning of 1943 the number of experienced pilots, normally defined as having more than 600 hours flying, had fallen by 25 percent from its peak and in February the tipping point was reached, which saw pilots with between 300 to 600 hours outnumbering experienced pilots for the first time.

Within several months the JNAF would be sending pilots into battle with less than 200 hours flying time. These new pilots were not only disadvantaged in combat but also in the seeming basic task of preserving their equipment. In February 1943, operational losses of aircraft began to significantly exceed combat losses; 161 were lost on take-off, flight or landing mishaps while 104 were shot down by enemy action. The high command of the JNAF either seemed unaware of the need for rotational relief or simply did not have the resources to provide it. Combat flying is an exhausting and high stress activity and many experienced Japanese pilots must have perished because their levels of concentration collapsed. In the JNAF, pilots literally flew until they dropped.

Sunday, March 13, 2016

B7A Ryusei

In June 1944, IJN Taihō, the only Imperial Japanese Navy aircraft carrier then large enough to operate the B7A Ryusei in its intended role, was sunk during the Battle of the Philippine Sea before enough B7As were even available to embark. Thereafter, the B7A was relegated to operating from land bases, primarily with the Yokosuka and 752nd Air Groups. The Japanese completed only one other carrier capable of operating the B7A, IJN Shinano, but she was sunk by an American submarine.

Aichi B7A1/B7A2 differences
I believe there are some minor differences in the cowling and exhausts because of the difference in the two versions engines.

According to Francillon, just 9 B7A1s were built. I have a picture of one with tail marking "Ko-B7-7", so this was presumably the 7th built, and it has a retractable tailwheel. I have not found any pictures purporting to be of B7A1s in service, and all in service seem to have had the fixed tailwheel.

The B7A1 was overweight and there were also structural problems in the wings. The wing internal structure was totally redesigned among other things, so there may be differences in panel arrangements.

According to Francillon, the only differences were a slightly improved engine version, and replacement of the rear 7.92mm gun with a 13.0mm.

The same two engine models were used interchangeably in the Ki-84 I (Ha[45]11 and Ha[45]12) with no alteration in outward appearance.

British CAP Interception
The four 'dusk' patrol Hellcats from the 1844 NAS detachment embarked in Formidable were airborne at the time, and they were quickly vectored onto a quartet of Aichi B7A 'Grace' torpedo-bombers flying at 20,000 ft on a heading for the ships. The Hellcats, flown by Sub Lts Atkinson, Foster, Mackie and Taylor, made short work of the rarely seen B7As, as is described in the official Royal Canadian Navy history;

'During his attachment to Formidable, Atkinson achieved a rare distinction on the night of 25 July. Four Hellcats were scrambled on a night combat air patrol. These were conventional Hellcat IIs without radar, but their pilots had been trained in night flying. Shortly after assuming patrol, incoming Japan- ese aircraft were detected. Two Hellcats were forced to return to the carrier unserviceable. Sub Lt Atkinson assumed the lead of the remaining two Hellcats and was vectored out on an intercepting course.

'Under a full moon, Atkinson identified the bandits as big, single-engined "Grace" torpedo-bombers, and took his New Zealand wingman, Sub Lt R F Mackie, into the attack. Atkinson latched onto a pair of "Graces" and shot them both into the water, while Mackie dumped the third. Then, in routing the other bandits, a fourth "Grace" went down and the enemy attack was completely broken up.

An intact and unused cockpit canopy discovered in Kumamoto Prefecture, Japan, has been conf rmed as an Aichi B7A Ryusei (Shooting Star) torpedo/dive- bomber. It is generally believed to be the only known part of the aircraft type, which was also used in kamikaze attacks, to exist in Japan. A spokesman from the local industrial heritage study group, said: "The canopy has historical value as it shows Japan's aeronautical industry heritage and conveys the tragic reality of war."

The Ryusei, which served the Imperial Japanese Navy, is sometimes referred to as the 'last suicide attack plane' because naval records show that two Ryusei aircraft departed on kamikaze missions on August 15, 1945, the day Japan surrendered to the Allies. Ryusei production began in April 1944 and its cockpit canopies were manufactured in Yatsushiro, Kumamoto Prefecture. Around 110 Ryusei aircraft were completed. The relic is considered a precious historical record because most Japanese wartime equipment was destroyed. The only remaining Ryusei is at the Smithsonian National Air and Space Museum in Washington, DC.