Interrogation of: Rear Admiral KATSUMATA, Seizo, I.J.N. (Retired), was Head Instructor at the Naval Mechanical and Engineering School in YOKOSUKA,.8 December 1941 to September 30, 1942; Commander of SAGAMINO Flying Corps at KANAGAWA, 21 April 1943 to 31 March 1944; Commander of 18th Combined Flying Corps at KANAGAWA, 1 April 1944 to 28 February 1945; Commander of 22nd Combined Flying Corps at KYUSHU, 1 March 1945 to 20 July 1945; Commander of 101st Flying Squadron at MIE-KEN, 22 July 1945 to 10 October 1945.

Interrogated by: Lieut. Comdr. R. P. Aikin, USNR.

Allied Officers Present: Lieut. Robert Garred, USNR.


1. Until the summer of 1944 when an air ferrying command (101 KOKUSENTAI) was organized, replacement aircraft for tactical units overseas were generally delivered by combat pilots who returned to the EMPIRE where they picked up new planes. The division of responsibility between maintenance and delivery crews (i.e. combat pilots) resulted in excessive ferrying losses. To centralize this responsibility and thereby reduce wastage, an air ferrying command was established.

2. Prior to 1943 planning was based on a flight personnel attrition rate of 20-30%. In 1943 this rate revised upward to 50% and the pilot training program accordingly accelerated.

3. Gasoline shortages necessitated abandoning the intermediate phase of the pilot training program late in 1943. This increased operational losses.


Said Rear Admiral KATSUMATA: Before my entrance into the 101 KOKUSENTAI, I was attached to an educational maintenance unit. I am not familiar with the figures of aircraft losses. I remember hearing much on the subject, but do not feel qualified to estimate attrition rates. The main reason for the formation of the 101 KOKUSENTAI was to reduce the attrition rate by overcoming problems in poor maintenance, unskilled flight personnel and too close figuring on allowable gasoline consumption. We felt by forming the 101 KOKUSENTAI to reduce this figure by giving aircraft the proper maintenance before leaving for tactical units and by supplying properly trained flight crews for delivery of the aircraft to the units. Previously, delivery had been made by members of tactical units returning to the EMPIRE to ferry the planes to their units.

I believe the reason for the excessive attrition rate in delivery of aircraft, was the division of responsibility between maintenance and delivery crews--the lack of coordination between the two departments. It was the job of the 101 KOKUSENTAI to centralize this responsibility. We were successful in reducing losses.

I have heard that the attrition of aircraft in training units was excessive. I also heard that attrition in tactical units was much greater. Tactical losses were caused to a large degree by the gasoline shortage and the resultant lack of adequate training. It is true that we saw the gasoline shortage coming in 1943 and at the same time increased our pilot training program. We hoped that someway we could get adequate gasoline supplies. The necessity for obtaining trained pilots was so great that we increased our training program in the face of an impending fuel shortage.

Q. Had tactical losses during 1942 exceeded pre-war estimates?
A. As nearly as I know, 1942 losses were no greater than expected.

Q. Why was the training program accelerated in the spring of 1943?
A. In 1943 we operated on the assumption that 50 percent of our flight personnel would be necessarily expended. Before 1943, our estimate of the attrition rate had been 20 to 30 percent. I don't know what caused this upward revision. I believe the Battle of GUADALCANAL and the actions at RABAUL had more to do with the revision than the Battle of MIDWAY. Toward the end of 1943 our operational losses were aggravated by the discontinuance of the intermediate phase of the pilot's training program. Operational training was carried on with tactical units and in combat aircraft. This change in the training program was made because of the gasoline shortage and the need for pilot replacements. It resulted in heavy losses.


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