CHAPTER 4 - WWII JAPANESE AIR SERVICE - SECTION 1



TABLE OF CONTENTS








SECTION I - GENERAL



1. GENERAL.

Japan does not have an independant air force. The Japanese army air force is an integral part of the army. As the Japanese naval air force is of the navy. Most of this section of the website deals with the army aviation. However, some information about naval aviation operations is provided.

2. HISTORICAL SUMMARY.

a. The Japanese army began experimenting with airplaned in 1911. It laid out the foundation of its air branch under the guidance of French military aviation instructors in 1919. In that year an aviation section was created in the War Ministry. The first military aviation school was opened at Tokorozawa in 1920 and two years later, schools were established at Shimoshizu and Akenogahara.

b. By 1935 there were eight Hiko Rentai (air regiments) believed to have been controlled by several ground headquarters of the army. The Hiko Rentai were later renamed Hiko Sentai , a more dynamic term. These air regiments were not put under the Koku Hombu (air headquarters), which wasorganized under the war ministry in 1935 to centralize control of manufacture, supply and other aspects of the air arm.



c. In 1936, however, a form of administrative and operational headquarters called Koku Heidan (air groups), was created to provide the first separate operational control of the flying units. This type of headquarters was expanded in 1938 into Hikoshudan (air groups). The Hikodan (air brigades) were created in 1940 presumably as intermediate headquarters between the Hikoshudan and Hikosentai (air regiments).

d. In the spring of 1942, the administrative and operational setup for controlling flying and oher field units of teh air arm was greatly expanded. The Hikoshudan (air groups) were conveted into Hikoshidan (air divisions) in April 1942, and Kekugun (air armies) were established on 1 June 1942 to control the several Hikoshidan .


e. Throughout the reorganizations, the successive operational headquarters were under divided supervision, taking operations orders from the Army's Inspector General of military training until the Koku Sokambu (Inspector General of Aviation) was established in December 1938 to control aviation training.



3. CONTROL OF THE ARMY AIR FORCE.

a. Supreme command of the Japanese Armed Forces, both army and Navy, is lodged in the Daihonei (Imperial General Headquarters), a war time organization superimposed on the peace time organizational structure. This headquarters comprises Chiefs of the Army and Navy, and specially designated officers.

b. The Army Air Force follows the pattern of division of authority of the Japanese Army itself in that:
The Chief, Army General Staff is responsible for mobilization and operations.
The Inspector General of Aviation supervises aviation training.
The Chief, Air Headquarters, under the War Minister, controls administration, supplpy, personnel, and technical training (See fig 65).

c. The same man consistently has been both Inspector General of Aviation and Chief, Air Headquarters. He is thus the administrative head of the Army Air Force, controlling it in all respects except aviation training; in directing training he is subordinate only to the Emperor (in wartime presumably to Imperial General Headquarters).


SECTION II - ORGANIZATION OF THE ARMY AIR FORCE



1 ADMINISTRATIVE.

A. Koku Sokambu (Inspector General of Aviation)

(1) The Inspectorate General of Aviation was established in December 1938 to plan and supervise the training of flying and maintenance personnel. There was precedence for the new organization in the Army, Where the Inspector General of Military Training was on an equal footing before the throne with the Chief, Army General Staff and the war minister, and therefore to some degree, in peacetime at least, independant in his sphere.

(2) The Inspector General of Aviation took over functions for the army air force similar to those the Inspector Generalof Military Training performed for the army ground forces. He was ranked "with but after" the three principal army officials (Chief of the Army General Staff, War Minister, Inspector General of Military Training), and was made responsible only to the Emperor for Army Aviation Training. This move gave the Army Air Force prestige and to a considerable extent appeased pressure for an independant air force.

(3) All the inspector General of Aviation have been concurrently chiefs of Air Headquarters, which is primarily concerned with procurement and supply. Further, most of the Section Chiefs of the Inspectorate General of Aviation have been concurrently chiefs of corresponding sections of Air Headquarters. As a result of this practice, the training procurement and supply of the Army Air Force are substantially in the hands of one chief and staff,although the men have posts in two headquarters.

(4) The creating order in December 1938 provided for three departments and the Inspectorate general of Aviation, and there are indications that no change has been made up to early 1944. The departments , which principal duties assigned are as follows:

(a) General affairs department: Organization and ordnance of subordinate schools; fiscal, supply and general duties.
(b) Training department: Training of air personnel and supervision of subordinate schools.
(c) Medical department: General medaical functions and training of personnel in aviation medicine.



B. Koku Hombu (Air Headquarters)

(1) Air Headqurters was established under the War Ministry in July 1935 to control all functions of the air arm except operations and aviation training. It supervided manufacture and supply of materiel and fuel, air signal communications and the meteorological service. These functions were performed via six headquarters departments and five subordinate organizations.

(2) The order creating Air Headquarters, as ammended in 1941, provided for four departments, namely General Affairs Department and department Nos 1,2 and 3. The number of departments was expanded to six in a reorganization effective in October 1942. The Maintenance department established on October 1942 was renamed the Supply Department in February 1944; the Chief and most of the personnel were retrained.

(3) The six departments of air headquarters with principal duties assigned as of October 1942 are as follows:

(a) General affairs department: General affairs. Personnel and allowances; general matters relating to airfields, bombing and firing ranges; air intelligence and counterintelligence; air consciousness propagabda.

(b) Training department: Use of airfields and ranges; air signal communications; metereology; training of air technical officers and men (inspectors amd ordnance men assigned to air depots, etc.)

(c) Maintenance department (renamed Supply Department February 1944): Maintenance of aircraft ordnance and storage of fuel; promotion and supervision of air ordnance industries; purchase, storage, distribution, exchange, repair, and inspection of aircraft ordnance and fuel (presumably including aircraft); matters relating to raw materials, power and machine tools needed for aircraft production and for expansion of aircraft factories.

(d) Technical department: Design and experimentation with aircraft ordnance (presumably including aircraft); designation of model nmumbers (standardization) for aircraft ordnance and fuel; supervision of aviation research agencies; repair of air navigation equipment and equipment in fixed radio stations.

(e) Intendance department: Air budget abd settlement of air accounts (presumably for purchases and payments for the Army Air Force); contracts, buying and selling, and loans.

(f) Medical department: Research in aviation medicine; medical supervision of agencies subordinate to Air Headquarters.

(4) Air Headquarters , under the direction of the war ministry, also controls the following five organizations:

(a) Koku Gijutsu Kenkyujo (Air Technical Research Laboratory). The Koku Gijutsu Kenkyujo is charged with research and experiment on aircraft ordnance and on aviation fuel, oil, medical supplies, clothing, and provisions.



(b) Koku Shinsabu (Air Examination Department)
  1. The Koku Shinsabu is responsible for the examination and inspection of aircraft ordnance, aviation fuel, oil, medical supplies, clothing and provisions, in addition, it conducts initial trainingwith new types of aircraft.
  2. The Koku Shinsabu was established in October 1942. It apparently supervised the Hiko Jikkenbu (Air Testing Department, sometimes translated as Air Experimental Department. Both Shinsa and Jikken sometimes appear in translations as "investigation"). The Hiko Jikkenbu was established under Air Headquarters in December 1939. No references to Hiko Jikkenbu have been seen since September 1942. One of its functions, training in the use of new plane types, has been assigned to the Koku Shinsabu (Air Examination Department), but it has not been deternmined which agency took over Hiko Jikkenbu's principal duty, flight tests of new planes.
(c) Kokusho (Air Depots)
  1. The highest administrative supply office under Air Headquarters is the Kobu Honsho (Air Main Depot) in Tokyo. Subordinate to it are the Koku Shisho (Air Branch Depots). Recent evidence indicates a reorganization at least involving the droping of "branch" from the names of the subordinate depots.
  2. The Koku Honshu (Air Main Depot) and its subordinate depots are responsible for purchase, storage, preservation and supply of aircraft ordnance and aviation fuel. they also repair aircraft ordnance and dispose of obsolete weapons and equipment.
  3. In June 1941 the Koku Shisho (Air Branch Depots) were instructed to set up technical training schools to give three-year engineer apprentice courses and one-year special technical courses for employees of the air depots and of materiel depots at the air schools.
(d) Koku Kosho (Air Arsenal) The Koku Kosho produces aircraft in its own factories and supervises production in non-military plants. It consists of four sections (General Affairs, Planning, Inspection and Finance); aircraft factory (or factories); Engine factory (or factories); and Technicians Training Center. On request, the Koku Kosho repairs aircraft.

(e) Kishobu (Meteorological Department). Established in April 1938, under the divided supervision of the War Minister, rge Chief of the Army General Staff, and the Chief, Air Headquarters, the Kishobu subsequently (October 1942) was placed under the Chief, Air headquarters. Its duties include research and compilation of statistics for military metereology, supervision of metereological supplies, and training of metereological personnel.It also is the administrative headquarters for metereological stations.

C. Miscellaneous Administrative Organizations

(1) Koku Tekisei Kensa (Air Qualification Examination Department). Organized in January 1944, the Koku Tekisei Kensa is headed by a colonel and staffed by medical officers, some of whom also are attached to air schools. The department appears to be in charge of physical examination of Army Air Force personnel, a function formerly supervised by the Air Headquarters. Its subordination has not yet been determined.

(2) Koku Yosubu (Air Transport Department). The Koku Yosubu appears to be responsible for the central direction of air transport and the ferrying of replacement aircraft. Until January 1944, the ferrying system operated through departments at Tachikawa and Kagamigahara . In January the system was reorganized and ferrying was placed more directly under the Koku Yusobu . Its subordination is not known.




2. TACTICAL.

a. Kokugub (Air Armies) The Kokugun are the highest Army Air Force headquarters for control of flying and service units in the field. They operate in clearly defined areas covering, in addition to Japan, Manchuria, and Korea, the whole of Japanese occupied territory. The Kokugun , as a type of headquarters, was created on 1 June 1942; commanders of the 1st and 2nd Kokugun were appointed on that day, and the commander of the 3rd Kokugun was appointed soon afterward, on 9 July 1942. The creating order places the Kokugun commander under divided supervision, making him responsible to the Chief , Army General Staff, for mobilization and operations; to the War Minister for administration and personnel; and to the Inspector General of Aviation for training (see fig 65). In the field, the Kokugun receives its orders through the Theater Commander. Kokugun are for the most part administrative headquarters, however, and in many instances the Hikoshidan (air Divisions) - The next lower echelon - received their operations orders directly from the Theater Commanders or from area or numbered ground armies rather than from Kokugun . Kokugun headquarters include six sections; operations, adjutant, ordnance, intendance, medical, and judicial. from the standpoint of function, a Kokugun is roughly equivalent to a United States Theater Air Force (strategic and tactical).

b. Hikoshidan (Air Divisions) (See figure 66)
  1. The Hikoshidan are the largest tactical units of the Japanese Army Air Force. Subordinate to the Kokugun , though sometimes directly controlled by an area or numbered ground army, the Hikoshidan have operational and administrative control of the air units within specific areas, which change in accordance with the strategic situation. Hikoshidan correspond roughly to teh Air Forces of the United States Army.
  2. The Hikoshidan were created as a type of headquarters in April 1942. They superseded the Hikoshudan (Air Groups), which had been set up in June 1938. This reorganization was coincidental with the expansion of the Army Air Force and was in preparation for the establishment of three Kokugun (Air Armies) a few weeks later. Although the establishing order set up the type of organization without mentioning the number of units, the droping of the term Hikoshudan for Hikoshidan is an indication that several Hikoshudan in Japan and overseas were simply expanded and redesignated in preparation for regrouping under three Kokugun .
  3. ten Hikoshidan have been identified. The commander is usually a lieutenant general, but may be a major general. The Hikoshidan normally controlled two or more Hikodan (Air Brigades) and an equal number of Koku Chiku Shireibu (Air Sector Commands), the latter being charged with administrative and servicing functions at the level of a brigade.
c. Hikodan (Air Brigades) The Hikodan , organized in July 1940, and modified in June 1942, are flexible and mobile tactical organizations. They consist of a small headquarters, a reconnaissance squadron, and usually three Hikosentai (Air Regiments), although the composition and strength vary with the mission. Hikodan comprise any combination of fighter, bomber, and reconnaissance regiments. Two or more Hikodan may operate simultaneously in an area. The commander is usually a major general or a colonel, but may be a lieutenant colonel. Hikodan are more or less equivalent to a United States wing or division.




d. Hikosentai (Air Regiments) . The Hikosentai are the basic tactical units of the Japanese Army Air Force. Each Hikosentai normally has a single type of aircraft, although in a few cases a reconnaissance squadron is included with fighter or bomber squadrons. The table of equipment strength of a fighter Hikosentai is 49 aircraft organized into three Chutai (Squadrins) of 16 aircraft each, plus the commanding officer's plane. Bomber units have a table of equipment strength of 37 aircraft, including three Chutai of 12 aircraft each. Operational strength, however, is usually below the T/E strength, abd there are some indications that the T/E strength is variable. Hikosentai are usually commanded by a lieutenant colonel or a major. Usually subordinate to a Hikodan or Hikoshidan , they sometimes are placed directly under the control of ground armies. A Hikosentai compares in some respects with a United States group.

e. Dokuritsu Hikotai (Independant Air Units)
The Dokuritsu Hikotai were organized as administrative headquarters controlling one or more Dokuritsu Hikochutai (independant Air Squadrons), performing long distance reconnaissance, army cooperation, anti-submarine patrol, and similar tasks for armies. These are indications, however, that some of them are being reorganized into standard Hikosentai . The commander usually is a lieutenant colonel or a major.

f. Dokuritsu Hikochutai (Independat Air Squadrons) Dokuritsu Hikochutai are operational flying units with a table of equipment strngth of 12 aircraft. These units originally were reconnaissance units attached to Hikoshidan or Hikodan headquarters, or operating under Dokuritsu Hikotai (Independant Air Units). Some however, have been identified as bomber squadrons , and at least two have been identified as fighter units. The commander usually is a captain or a first lieutenant.

g. Chokkyo Hikotai (Direct Cooperation Units). Chokkyo Hikotai, established in April 1942, are attached to armies or divisions for reconaissance, liason, and artillery observation and fire control duty. They are equipped with obsolescent light bomber-reconnaissance aircraft and usually are commanded by a Captain.

h. Koku Shashin Tai (Air Photography Units). Only one Koku Shashin Tai (the 1st) has been identified. The unit has Dinah, Topsy, and Helen aircraft.

i. Teishin Tai (Raiding Units) a Teishin Dan has under its control two or more Teishin Rentai (raiding Regiments) and one or more Teishin Hikosentai (Raiding Air Regiments). The Teishin Rentai are believed to be composed of ariborne and parachute troops. The Teishin Hikosentai are equipped with transport planes are are used to mobilize the airborne and paratroopers. One Teishin Hikosentai has been identified, but its relation to the other unit has yet to be determined. Note that the word "Teishin" when applied to troops not using aircraft translates to "Commando".

j. Kakkuki Hikosentai (Air Glider Regiments)
Beyond the implications of its name, the Kakkuki Hikosentai's functions are not known. The first regiment was organized in August 1943, with a lieutenant colonel as commander.