Hey Gang,
The early war Japanese twin bombers are represented by only the Ki-21 Sally. While I would love to see the G3M Nell represented for its virtuous early exploits, it was built in fewer numbers, and lasted a shorter time in front line operational service than the Ki-48 Lily.
Impressed with the qualitiesof the Soviet SB-2 encountered in the Sino-Japanese War in 1937, the Japanese requested and recieved permission to develope a light twin engine bomber of like attributes. Kawasaki Aircraft Ltd. was issued the specifications in December 1937. These called for a twin-engined light bomber with (a) a top speed of 298 mph at 9,845 feet; (b) a cruising speed at the same altitude of 217 mph; (c) climb to 16,405 feet in 10 minutes; (d) a bombload of 882 pounds; (e) engines to be Nakajima Ha-25 radials; (f) defensive armament of three or four flexible 7.7mm machine guns; and (g) ability to operate under the extreme winter conditions prevailing in Manchuria and North China.
As the designer ( Takeo Doi) was already involved with other design work (the Ki-45) the Ki-48 was not ready for flight until July 1939.
The cantilever wing was mid-mounted to allow an internal bomb bay. The crew of four was to consist of the pilot, a bombardier/nose gunner with a 7.7mm weapon at his disposal, a radio-operator/gunner manning the dorsal 7.7mm machine gun, and a navigator/gunner utilizing the ventral 7.7mm gun.
Normal bombload was to be 24 x 33-lb. bombs or 6 x 110-lb. bombs, and the twin engines were, as per the requirements, Nakajima Ha-25s driving three-bladed variable-pitch propellers.
The prototype easily met all performance requirements and won praise from Army test pilots for its manoeuvrability and handling characteristics, but it suffered from severe tail flutter. Five further prototypes, built between September and November of 1939, tested various tail-surface modifications, until it was found that raising the horizontal stabilizers approximately 13 ¾ inches and generally strengthening the rear fuselage was the combined solution to the flutter problem. Very late in 1939, quantity production of the new light bomber commenced under the designation Army Type 99 Twin-Engined Light Bomber Model 1A, or Ki-48-Ia.
The first production Ki-48-Ia was completed in July of 1940, and by that autumn, the 45th Sentai (Group) was re-equipped with the new aircraft and deployed to the North China battlefront, where the Ki-48 swiftly won a high reputation with its crews. Facing largely token Chinese opposition, the Ki-48 performed satisfactorily, winning much praise for its high speed. In addition to daylight tactical sorties, night strategic attacks were pioneered by the 45th Sentai, in preparation for similar attacks on the forces of the Western Allies in the upcoming Pacific War. Late production Ki-48-Is were designated Ki-48-Ib, differing from the earlier model solely in having minor internal equipment changes and improved machine gun mountings.
When the Pacific War began, the Ki-48 was the most important JAAF light bomber outside the Chinese front; the older single-engined Ki-30 and Ki-32 were retained for China service. Aircraft of the 8th, 27th, 75th, and 90th Sentais were deployed against Commonwealth forces in Malaya and Burma, and against the Americans in the Philippines, before being transferred to the Dutch East Indies, and later to New Guinea.
But against Allied fighters of more modern vintage, the Ki-48-I fared badly; the high turn of speed it was so praised for over China was too slow to allow the Lily, as the Allies code-named it, to avoid interceptors. Also, its defensive armament was wholly inadequate, its bomb load was too small, and it lacked any form of crew or fuel-tank protection. To limit combat losses, the early model Lilies were used for night attacks whenever possible, reducing their effectiveness even more.
Ventral MG
Dorsal MG
Bombay Open
An improved model of the Lily was already being developed as the Pacific War commenced. The Ki-48-II differed little from its predecessor, but it incorporated a slightly lengthened fuselage, improved engines (Nakajima Ha-115s with a two-stage blower), some fuel-tank protection, and some armour for the crew, including a 12.5mm plate behind the bombardier's seat, a 6.5mm plate under the pilot's seat, 16.5mm armour behind the pilot's seat, and 16.5mm plates to protect the dorsal and ventral ammunition boxes. Within two months of its first flight, the Ki-48-II entered production as the Ki-48-IIa. These production planes differed from the prototypes only in minor details, such as local strengthening of the fuselage. The Ki-48-IIb was a dive bomber, fitted with retractable dive brakes under the outer wings (these were of the "snow-fence" variety).
The maximum bomb-load of the Ki-48-II was double that of the -I, but it was still a great deal less than that of the standard Allied light bomber, the A-20 Havoc. And although the speed of the Ki-48-II was superior to that of the -I, it was still not fast enough to outrun the improved Allied fighters of the later-war period. But its worst failing was its woefully inadequate defensive armament, which had not been improved since the prototype first flew. The Lily proved to be "easy meat" in the air, and large numbers were also destroyed on the ground in New Guinea despite Japanese efforts to disperse and camouflage the planes on their jungle airstrips.
The final production variant, the Ki-48-IIc, received a 12.7mm machine gun in a flexible dorsal mounting, plus a second nose-mounted 7.7mm machine gun; the bombardier could use either gun as needed (one at a time!!). Still, despite all attempts to keep the Ki-48 a viable warplane, it was obvious the type was obsolescent, and so production ended in the autumn of 1944, as noted above. Some Ki-48-IIs continued to serve in a conventional bombing role, mainly at night, in the Philippine and Okinawan campaigns. But most surviving Lilies were expended in daylight suicide attacks in the latter campaign, usually en masse, in the Kikusui (Floating Chrysanthemum) raids. A number of Ki-48-IIs were modified as Ki-48-II-KAI special attack planes by the Army Air Arsenal at Tachikawa. These carried a 1,764-lb. bombload, triggered upon contact with the target by means of a long rod protruding from the aircraft's nose like a mosquito's proboscis.
Four Ki-48-IIbs were used in 1944 to test the Kawasaki I-Go-I-B air-to-surface guided missile, and another Ki-48-II was used to test the experimental Ne-O turbojet in flight; to accomplish this, the bomb-bay doors were removed and the jet engine was slung under the fuselage. In addition, two proposed but never-built variants were the Ki-81 formation commander's aircraft, heavily armed and armoured; and a single-seat special attack aircraft, the Ki-174.
Kawasaki Type 99 Ki-48 (Lily) Technical Data
Type:
Twin-engined light bomber, of all-metal construction with fabric-covered control surfaces.
Accommodation:
Crew of four in enclosed cockpit/cabin.
Powerplant:
(Prototypes and Ki-48-I) Two Nakajima Ha-25 fourteen-cylinder air-cooled radial engines, rated at 1,000 hp for take-off and 980 hp at 9,845 ft.
(Ki-48-II) Two Nakajima Ha-115 fourteen-cylinder air-cooled radials, rated at 1,130 hp for take-off, 1,070 hp at 9,185 ft., and 950 hp at 18,375 ft.
Armament:
(All except Ki-48-IIc) Three flexible 7.7mm machine guns, one each in the nose, dorsal, and ventral positions.
(Ki-48-IIc) Two nose-mounted flexible 7.7mm machine guns, one ventral-mounted flexible 7.7mm machine gun, and one dorsal-mounted flexible 12.7mm machine gun.
Bomb load:
(Ki-48-I) Normal, 661 lb.; maximum, 882 lb. (Ki-48-II) Normal, 882 lb.; maximum, 1,764 lb.
Dimensions, weights, and performance:
Ki-48-I 557 of Ki-48Ia and Ki-48Ib built :
Wingspan, 57 ft. 3 25/32 in.;
length, 41 ft. 1 1/16 in.;
height, 12 ft. 5 19/32 in.;
wing area, 430.555 sq. ft.;
empty weight, 8,929 lb.;
loaded weight, 13,007 lb.;
maximum weight, 13,338 lb.;
wing loading, 30.2 lb./sq. ft.;
power loading, 6.5 lb./hp;
maximum speed, 298 mph at 11,485 ft.;
cruising speed, 217 mph at 11,485 ft.;
climb to 16,405 ft., 9 minutes;
service ceiling, 31,170 ft.;
normal range, 1,230 miles;
maximum range, 1,491 miles.
Ki-48-II 1,408 of Ki-48IIa, Ki-48IIb, Ki-48IIc built:
Wingspan, 57 ft. 3 in.;
length, 41 ft. 9 31/32 in.;
height, 12 ft. 5 19/32 in.;
wing area, 430.555 sq. ft.;
empty weight, 10,031 lb.;
loaded weight, 14,330 lb.;
maximum weight, 14,881 lb.;
wing loading, 33.3 lb./sq. ft.;
power loading, 6.3 lb./hp;
maximum speed, 314 mph at 18,375 ft.;
cruising speed N/A;
climb to 16,405 ft., 8 min. 30 sec.;
service ceiling, 33,135 ft.;
normal range, 1,274 miles;
maximum range, 1,491 miles.
A Little "Loving and Giving" for Friday
PS no dis for Max the Hitman who had this aircraft high on his list also.
kopfdorfer
Author
Topic: Friday's Child - Kawaski Ki-48 Lily (Read 8620 times)
