Hi Kopfdorfer,
47 Dokuritsu Chutai or Kawasemi Butai (Kingfisher Force)
KINGFISHER FORCE
Prior to Japan's attack on the Western Allies in December 1941, its Army Air Headquarters had watched the conflict in Europe with close interest. Secret intelligence reports from the air attaches in Berlin and London included not just assessments of the capabilities of Luftwaffe and RAF aircraft, but also the development of air doctrine over Europe and the influence of combat experience from both sides.
An awareness of an increasing emphasis on altitude, hit-and-run tactics and an expectation that the RAF would deploy the Spitfire to defend their Far Eastern possessions accelerated commitment of the Shoki to Japan's initial attack. Consequently it was decided that the aircraft's pre-production trials would not be confined to China, but would instead become part of the Japanese attack on Malaya. An experimental unit of pre-production Ki-44s would be formed to test the aircraft — and its concept - in battle. Here was the second departure, because the Ki-44 would be committed from the outset to an offensive fighter role, which was somewhat challenging to its design profile.
In August 1941 leadership of the JAAF's experimental unit was assigned to 31-year-old Maj Toshio Sakagawa from Hyogo Prefecture. He had served with the 11 th Rentai and 24th Sentai in China, but had had little opportunity to engage in combat. Sakagawa was, however, a dynamic and proficient leader who would later command the Ki-43 'Oscar'-equipped 25th Sentai almost throughout the entire campaign in China, before being killed in the accidental crash of a transport aircraft returning him to Japan from the Philippines on the night of 19 December 1944. He would be credited with approximately 15 victories at the time of his death.
Sakagawa's new experimental unit was formed at Tachikawa airfield, in Japan, in early September 1941. Staffed with experienced personnel assigned from the JAAF's Flight Test Centre, it was designated the Dokuritsu 47th Hiko Chutai (Independent 47th Air Squadron). Its name was said to be in recognition of the legendary Japanese tale of the 47 Ronin, a band of samurai who took revenge for their assassinated leader. However, the unit became unofficially known as the Kawasemi Butai (Kingfisher Force), reflecting the new tactics that were to be pioneered, or rather more informally the Shinsengumi ('newly selected band' or 'chosen ones'). On 5 September seven pre-production aircraft and the second and third Ki-44 prototypes were issued to the new unit as its primary equipment.
The engine chosen for the new fighter was the Nakajima Ha-4l of 1250 hp that had been developed for heavy bombers, and whose powerful bulk was fitted to the Ki-44's airframe with skilful streamlining. The aircraft also had a slab-sided fuselage behind the centre of gravity to improve stability. Pre-production models were capable of reaching speeds of 374 mph at an altitude of 12,860 ft, with an impressive rate of climb.
The design team had mated the large Ha-4l engine to the smallest airframe possible, with wings of only 161.46 sq ft creating a high wing loading of 30 lb/sq ft. Professor Hideo Itokawa had suggested the unusually small wing in order to address the Koku Hombu requirement for the aircraft to possess excellent gun platform characteristics. Professor Itokawa advised that a short span wing with strictly limited dihedral would reduce excessive lateral stability, whilst an increased fuselage profile area would achieve the directional stability required. During high-speed trials at Ota, senior Nakajima test pilot Hayashi had dived the aircraft 9840 ft to reach a speed of 528 mph, without experiencing any adverse handling characteristics whatsoever.
In a further departure from the norm for JAAF fighters, the new aircraft was relatively heavily armed. The Ki-27 had only two synchronised 7.7 mm rifle-calibre machine guns firing through the propeller, and early examples of the Ki-44's contemporary, the Ki-43, had the same limited armament (although by the outbreak of the Pacific War the Ki-43 was armed with either one or two 12.7 mm machine guns). Pre-production models of the Shoki introduced wing armament in the form of two 12.7 mm Army Type 1 Ho-103 machine guns firing to a muzzle velocity of 2657 ft/sec at 900 rounds per minute, with 250 rounds of belted ammunition in each wing. The Ki-44 also retained the then-standard JAAF fighter armament of two synchronised Army Type 89 kai 7.7 mm machine guns (with 500 rounds each) in the upper cowling firing through the propeller.
Another innovation to benefit the Ki-44 was the fitting of special Fowler-type wing flaps which, as well as providing the aircraft with additional lift for take-off and landing, could be used in flight to decrease the turning circle during combat. To facilitate this, the flaps were operated by two buttons on the top of control column. These were often mistaken for gun firing buttons. These devices became popularly known as a 'butterfly' flaps. Some Japanese sources state that they were first fitted to the 12th limited production machine serial number 112 following development for the Ki-43, which means that the aircraft supplied to the Kawasemi Butai lacked the flaps. However, it seems more probable that they were installed from the outset on all Ki-44s. The prototype aircraft had been constructed in August 1940, while the butterfly flaps were first introduced on the 11 th Ki-43 pre-production aircraft serial number 4311, which was constructed during that same month. In other words, the technology was an integral part of the Ki-44 design, and the flaps' success was exploited to improve the Ki-43.
In addition to Commander Sakagawa, the pilots assigned to the Kawasemi Butai were Capts Susumu Jinbo and Yasuhiko Kuroe, lLt Shunji Sugiyama, WOs Etsuji Mitsumoto, Tokutaro Takakura and Naosuke Okada and MSgts Takao Ito and Satoshi Tanaka. The Chutai was organised into three Hentai (Flights) of three aircraft each, commanded by Sakagawa, Jinbo and Kuroe respectively.
The 'chosen ones' had little time to familiarise themselves with the new aircraft before being ordered to move to Saigon in French Indochina (occupied by the Japanese in 1940). The 47th left Tachikawa on 3 December 1941 for Canton in China, where it learned of the outbreak of hostilities on 8 December. The following day the unit moved on to Saigon to be assigned to the Southern Area Army's direct command in preparation for combat operations. The Ki-44s were hastily camouflaged with brown paint to match the predominant earth colour of the region, before being committed to battle. The insignia chosen for the new unit - the design on the Yamaga-ryu drum used to signal the attack of the 47 Ronin - was painted beneath the cockpit of each fighter.
From Saigon the squadron moved on to Don Muang, in Thailand, on 24 December 1941, but Sakagawa and two other pilots suffered mechanical problems en route, resulting in the unit being reduced to just six serviceable aircraft. The move had been prompted by disastrous bomber attacks against Rangoon on 23 December, where the aggressiveness of the Allied fighter defence - Tomahawks of the American Volunteer Group (AVG, the famous 'Flying Tigers') and the Brewster Buffalo fighters of the RAF's No 67 Sqn - had taken the Japanese by surprise.
Although requested to participate in the next wave of air attacks on Rangoon by providing a potentially lethal top cover, Sakagawa had to scrub the mission for the 47th because the Ki-44 had insufficient range to fly such distances, and he could not risk using the rough and limited staging fields at Raheng and Phitsanulok. The experimental unit was therefore relegated to protecting the bombers as they staged through Don Muang on their way to bomb Rangoon.
In early January 1942 the 47th had its first taste of what was to become a common theme for the JAAF fighter units when it was suddenly switched to support air operations over Malaya. The 47th moved to Kuantan, on the east coast of Malaya, and on 15 January flew its first mission over Singapore when the Ki-44s joined Ki-43 'Oscars' of the 59th Sentai and Ki-27 'Nates' of the 1st Sentai escorting bombers raiding Tengah and Sembawang.
Kuroe, Jinbo and two wingmen were flying together when they spotted the Buffalo of 26-year-old New Zealander Pit Off Greville 'Butch' Hesketh of No 243 Sqn leading a section of No 488 Sqn Buffaloes up against the bombers. Kuroe made a diving attack on the Buffalo followed by Jinbo, both pilots scoring hits and then using the Ki-44's power to climb away. Kuroe attacked the disabled enemy aircraft again, and after five bursts of fire the Buffalo was shot down. Seriously wounded in the attack, Hesketh managed to crash-land beside the oil tanks near Alexandra Hospital, but he was dead by the time rescuers reached his wrecked aircraft. The Ki-44s were not recognised, being identified instead as 'Navy Type O' (Zero) fighters.
On the night of 20 January a bombing raid on Kuantan by Hudsons of No 8 Sqn RAAF resulted in four of the 47th's Ki-44s being damaged. Six days later Kuroe and Jinbo participated in the interception of a mixed force of RAF bombers that were attempting to destroy a large Japanese convoy approaching Endau. Kuroe, who had been aloft for some time, appears not to have attacked until Jinbo joined him. Of the ten Vildebeests lost over Endau by the RAF, the 47th claimed two, together with the No 232 Sqn Hurricane of Fit Sgt J Fleming.
By the end of January only one Ki-44 was serviceable, seriously limiting
the unit's further participation in the air operations leading to the fall of Singapore. During the fighting Kuroe had claimed three RAF Hurricanes shot down. After a period of refit and repair, four aircraft had been returned to serviceability by 8 February, which meant that the unit could help in the provision of air cover for the Japanese landings on Singapore Island. No further victories were scored, however.
On 9 February the 47th was ordered to prepare to participate in the final air attacks on the RAF's Burma airfields, and ten days later the four serviceable aircraft were flown to an ex-RAF dispersal field at Mudon, south of Moulmein in south-eastern Burma, where they were able to refuel with aviation fuel left behind by the British. The unit was assigned to Gen Eiryo Obata's 5th Air Division, which was planning to conduct a knockout blow against Mingaladon airfield on the outskirts of Rangoon.
Five days after the 47th's arrival, the airfield was strafed by Allied fighters, which set one of the Ki-44s on fire, destroying it. The following day (the 25th), the three remaining Ki-44s, piloted by Sakagawa, Mitsumoto and Kuroe, participated in a fighter sweep over Mingaladon with 44 'Nates' from the 50th and 77th Sentai. Three AVG Tomahawks and a single RAF Hurricane from No 17 Sqn, flown by American pilot Sgt J F 'Tex' Barrick, contested the sweep. A confused and swirling dogfight resulted in AVG and RAF claims for five 'Nates' shot down.
The Japanese pilots stated that they had been in combat with at least 20 fighters, and claimed no fewer than 16 shot down, two of which were credited to the Ki-44 pilots. In fact neither side had lost a single aircraft. Barrick was attacking a 'Nate' (which he claimed destroyed) when Sakagawa jumped him. As he tried to evade his opponent with a tight turn, one of the Hurricane's gun panels came open, causing the aircraft to 'flick' in the air. Barrick believed this had saved his life, for Sakagawa's Ki-44 was in a perfect firing position behind him. Unable to follow the Hurricane's sudden turn, the Japanese pilot dived away instead, followed by the remaining two Shokis. Barrick's Hurricane received no hits in the encounter, while the Ki-44s returned to Moulmein to refuel and re-arm.
That afternoon the Japanese struck Mingaladon again, this time with 12 Kawasaki Ki-48 'Lily' bombers from the 8th Sentai, escorted once more by the 'Nates' of the 50th and 77th Sentai and the three Ki-44s of the 47th. The JAAF force was met by AVG Tomahawks and 12 Hurricanes from Nos 17 and 135 Sqns. None of the Allied pilots reported seeing the new Japanese fighters during their engagements and, as had previously been the case, if the Ki-44s had indeed been noticed they were identified as 'Navy Zeros'. The Ki-44s were flying in line astern, with Sakagawa in the lead, when a Tomahawk suddenly attacked him in a gunnery run from his left. Evading this attack by skilfully jinking his machine, Sakagawa quickly latched onto another Tomahawk. Mitsumoto briefly pursued a second Tomahawk before being attacked by a third AVG fighter. Kuroe was flying too far behind to intervene, but he saw the encounter;
'This was the most dangerous moment, because Sakagawa and Mitsumoto were attacking and could not look around, so they did not see the enemy fighter that was positioned outside the battle area which now came in to attack. I went after him, but I was not fast enough. The enemy fired at Mitsumoto, then turned upside down and got out of the battlefield by diving fast.'
Mitsumoto's aircraft had been hit and he had been wounded in the attack, but he was able to return safely to Moulmein.
These operations had taken their toll on the Ki-44s, and their pilots were somewhat dissatisfied with the performance of the aircraft on operations, complaining about the lack of visibility from the cockpit, high landing speed and lack of manoeuvrability. These were pilots with combat experience in the nimble Ki-27, and they had watched the participating sentais equipped with these familiar aircraft engaging the Allied fighters in classic dogfights throughout the campaign to date. On the other hand, the new fighter's high speed when diving, excellent roll rate and heavy armament were appreciated.
As a result, even before the experimental assignment of the Kawasemi Butai had ended, the Koku Hombu decided to authorise the limited production of a further 40 Ki-44s after considering it to be suitable as an anti-bomber or interceptor fighter. These first limited production aircraft, designated Ki-44-Is, were fitted with the Ha-4l engine. The first four (serial numbers 111-114) were ferried to the 47th in Burma as much needed reinforcements immediately after their completion in January and February 1942. The 47th's original brown camouflage had been deemed unsuccessful over the verdant landscapes of South-East Asia. Indeed, it highlighted the new fighter's slightly Buffalo-like appearance, causing several near-miss 'friendly fire' incidents. Consequently, the reinforcement Ki-44s were painted a dark olive green.
On 4 March four Ki-44s of the 47th conducted a sweep over the Sittang area, encountering four Bristol Blenheim I bombers of Nos 45 and 113 Sqns that had sortied from Magwe to attack targets in the same area. In their first pass, the Ki-44s damaged all four bombers, before concentrating on the Blenheim I piloted by Fit Lt F S Lee. Three of the Shokis repeatedly attacked the bomber from the rear, whilst the fourth, flown by Sakagawa, made a head-on run at it, firing into the cockpit. Lee was mortally wounded in this attack and the Blenheim I crashed 60 miles east of Pegu. The Ki-44s followed it down and strafed the wreckage. Only the air gunner, Sgt L Walker, survived, managing to return on foot.
On 21 March the 47th joined a formation of 52 Mitsubishi Ki-21 'Sally' bombers, escorted by 14 Ki-43s of the 64th Sentai, on a raid against the RAF/AVG airfield at Magwe, where there was a concentration of Allied aircraft. A second wave of ten Mitsubishi Ki-30 'Ann' light bombers, escorted by 14 Ki-27s, followed. In response, six Hurricanes and three AVG Tomahawks rose to challenge the JAAF formations in a series of confusing dogfights over the airfield. During this fighting lLt Shunji Sugiyama of the 47th became the unit's first combat fatality when he was shot down and killed. The remaining Ki-44s moved into Pegu, in Burma, at the end of March.
Following the raid on Tokyo on 18 April 1942 by Col Jimmy Doolittle's B-25 Mitchell bombers, which had taken off from the carrier USS Hornet (CV-8), the 47th was ordered to return to Japan. Seven days later the unit left Burma for the Homeland. The combat debut of Nakajima's Shoki was over.
Capt Kuroe did not return with the unit, having been transferred to the 64th Sentai on 24 April and appointed commander of its 3rd Chutai as a replacement for Capt Katsumi Anma, who had been killed on 8 April. Kuroe would have a successful career with this unit, becoming one of the 64th's leading aces with a tally of more than 30 aerial victories. In January 1944 he was transferred to the JAAF's Air Inspection Department, where, as a major, he evaluated experimental aircraft and new weapons systems, including large-calibre cannon and air-to-air rockets, during operational sorties against B-29s.
Source:
OSPREY AIRCRAFT OF THE ACES 100,
Ki-44' Tojo' Aces of World War 2,
Nicholas Millman
I can try to help, squeeze sth. out, but it's not much I seem to find about that certain campaign. My main trustworthy source is of french descendance. A triple series in a aviation mag called Avions 119-121.
Ah, OK, good to know, 18. February, mmhh, so let's start there...
Ki-44-I series production began at january in Ota, as late as february 47 Dokuritsu Chutai received it's first
Ki-44-I (113), last aircraft (152) as late as May 1942. Initial batch of Ki-44-I was counting 40 a/c, serialed 113-152.
Capt. Yasuhiko Kuroe left the unit and was posted to command 64th Sentai's 3rd Chutai leader.
...
On their return leg in May to Japan 47 Dokuritsu Chutai was ordered to mainland Japan after the initial Doolittle's B-25s raid.
They took up base at Chofu, in early september moving to Kashima (Chiba prefecture).
Maj. Toshio Sakagawa gave command to Capt. Susumu Jimbo, who was known to have test-flown the Fw190 A-5 together with his 1st Chutai Pals.