Japanese Shipboard Fighter A5M2 - Update
by Nikolai Kruglov
Samolety Mira (Airplanes of the World) No. 3-4 March-April 1997
transl. By George Mellinger, Twin Cities Aero Historians
                After publication in the previous article of the journal, additional information has appeared about the testing of the Japanese shipboard fighter.  Lost in an accident, the A5M2 was delivered to the NII-VVS (Scientific Research Institute of the Air Forces) on October 28, 1938, which disproves the previously given theory about the capture of this machine in the course of military action at Khalkin Gol.  Most likely the aircraft came from China, but it is impossible to rule out the military conflict with Japan at Lake Khasan.[1]
                As was already stated, the motor was assembled from motors from three crashes.  Also, two blades of the standard propeller, had to be replaced by blades specially prepared at Factory No. 28 Soviet specialists were able to determine the remaining service life of the motor at 20 hours, and this did not permit completion of a complete flight testing regimen.
                Jumping forward, I note  that during testing the motor supercooled, particularly during gliding, even with the cowling opening completely shielded.  Attempting to improve the temperature conditions, the upward deflectors were removed from the cylinders, and at the front of the cowling and on the main cylinder heads were installed individual winter cowlings from an I-5 aircraft.
                The first flight of the A5M2 was completed by the pilot G. P. Kravchenko[2] on May 13, 1939.  Also flying the machine was A. I. Filin, the Chief of the NII-VVS.  In all, they completed 28 flights totaling 15 hours and 15 minutes.
                Servicing the aircraft seemed very simple, but preparing the aircraft for flight required no fewer than three people.
                From the evaluations of the results of flight testing it was noted that “the recorded data may be considered as approximations as the motor was not conditioned for the changed width of the blades of the propeller and profile.
                The flight characteristics of the aircraft were extraordinarily simple and accessible even for pilots of below average qualifications.
                Stability of the aircraft was good relative to all axes, thanks to the forward center of gravity (23.4% SAKh), the great angle of the wings (7%), and a fortunate ratio of the area of the tail unit and the length of the fuselage.  Aerial maneuverability was good. 
                At the same time  “...according to our flight data, in maneuverability and armament... the I-96 is less than the new maneuvering fighters of the VVS-RKKA  (Red Air Forces).”
                Attention of the specialists studying the machine is drawn to the suspended (supplementary) fuel tank.  Development of an analogous mechanism for the I-16 should give worthwhile results.
                Not long ago found documents permit the supplement of performance characteristics of the fighter, attained during testing.: Time to achieve altitude of 3000 meters - 4.3 minutes; take off and landing runs did not exceed 200m & 300 m respectively.  Time for a for a serial turn at a height of 1000 meters - 15 seconds, which was 0.5 seconds less than for an I-16 aircraft
                In addition to the A5M2, other Japanese aircraft were tested in the Soviet Union,   But more about that later.

[1]Ed. Note: Yes it is possible to rule out Lake Khasan which, like Khalkin Gol, was an area of JAAF responsibility.  Further, all evidence, including other Russian sources, shows that while the Soviet air units were active at Lake Khasan, the Japanese, for unknown reasons,  declined to commit their air units.
[2]Grigorii Panteleevich Kravchenko, twice Hero of the Soviet Union, flew as a volunteer in China in 1938 scoring 5 victories.  Over Khalkin Gol in 1939 he scored 10 more victories.  During WWII, in spite of assignment as a senior commander, he scored 5 victories against the Germans before being shot down and killed in 1943.