In the early stages of the war, the designation "Zero" probably was used erroneously
as a generic term for almost any type of Japanese fighter aircraft, and this has resulted
in a certain amount of confusion. As a matter of fact, the term "0" or "Zero" was derived
from the Japanese year 2600 which coincides with our year 1940, and merely indicates that
the aircraft was put into service originally in 1940.
The phrase "Zero" may refer to a single place carrier-borne fighter or to a similar version
on floats. In addition, it may be used to designate a float reconnaissance-biplane or
a two-engine land-based reconnaissance-fighter. As a matter of fact, Zero models of all
the aircraft mentioned above have been identified. They are known today by their code
names, "Zeke," "Hap," "Rufe," "Pete," and "Dinah." In addition, there is a bomber
called "Gwen" and a small submarine based float biplane called "Glen," both of which
bear the Zero classification.
At the present time, there are two Zero fighters, "Zeke'' and "Hap." "Zeke" is designated
by the Japanese as the Type Zero, Mark I, Carrier-borne Fighter, Model 2. The
designation of "Hap" is the same, except that "Hap" is Mark II where "Zeke" is Mark I.
"Zeke" is the fighter which has been encountered frequently in current operations in the
Southwest and South Pacific Areas. It is capable of a maximum emergency speed of about
326 miles per hour at an altitude of 16,000 feet. An outstanding feature of this aircraft
is its high rate of "zoom." It can "zoom" nearly vertically, and the "zoom" can be continued
for 1,500 to 2,000 feet depending upon the starting speed. This should not be considered,
however, as indicative of the rate of climb of this aircraft. The maximum rate of climb at
sea level has been found to be approximately 2,750 feet per minute. The service ceiling is
estimated at 38,500 feet. The normal range of this airplane is believed to be about 1,100 miles, but
by addition of a belly tank, which can be dropped at will, a maximum range of
some 1,700 miles at economical cruising speed is believed possible.
"Zeke's" low wing loading, steep angle of climb, well streamlined structural design and
exceptionally sturdy construction make it a highly maneuverable aircraft at moderate
speeds. However, in recent tests where "Zeke" was flown in combat maneuvers against
several of our aircraft, two points of weakness were detected in the Japanese fighter: (1) at
high speeds, the rate of roll is extremely slow, and (2) the engine cuts out if the
nose is lowered suddenly to enter a dive. In addition to these points, the vulnerability
of "Zeke's" fuel and oil tanks is well known since these aircraft carry neither armor nor
self-sealing protection for the tanks. In some instances in the past, it has been
reported that wings have been torn off Zero fighters when recovering from extended
dives at high speed. The model tested, however, although intentionally designed for
light construction, appears capable of reasonably high diving speeds if properly handled.
There are several other types of Japanese fighters at present in operation. Prominent
among these is "Hap," a new fighter with nearly square wing tips, reported as superior
to "Zeke" in maneuverability and to have an even higher speed and rate of climb. It is
reported that Japanese pilots of this plane have not hesitated to follow our fighters
in power dives, which may indicate an increase in structural strength.
"Nate" is another Japanese fighter which has seen service in many of the Pacific areas. This
is an older model (Type 97) and does not equal the speed or performance of the more
recent "Zeke" or "Hap." "Nate" is believed to have a top speed of approximately 250 miles
per hour at 13,000 feet altitude. With maximum fuel, at economical cruising speed, it is
believed to have a maximum range of slightly over 1,000 miles.
"Oscar" (Type I) is believed to be a more recent modification of "Nate." It has greater
maneuverability and a good rate of climb but is believed to be about 20 miles per hour
slower than "Zeke" at top speed. Like "Zeke," "Oscar" has an exceptionally long range
when carrying maximum fuel and is believed capable, under these circumstances, of
obtaining approximately 1,700 miles at economical cruising speed.
In addition to the land based fighters mentioned above, there is also a Zero floatplane
fighter called "Rafe." Except for substitution of the floats to replace the wheeled landing
gear, this aircraft is believed to be practically the same as "Zeke" structurally. It is
reported, however, to be considerably slower than "Zeke" and less maneuverable.
All of the Japanese fighters mentioned above, are powered with radial air-cooled
engines. "Nate's" engine has nine cylinders and is estimated to produce about
790 horsepower at an altitude of 11,500 feet. The engines used on the other fighters
are twin-row with fourteen cylinders, and are believed to produce 900 to 1,000 horsepower
at about 11,500 feet. The armament of "Zeke," "Rufe," and "Hap" consist of two 20-mm
Oerlikon type cannons, one in each wing, and two 7.7-mm machine guns firing through
channels in the upper part of the engine cowling and synchronized with the
propeller. "Oscar's" armament is believed to consist of one 7.7-mm and one 12.7-mm
machine gun firing forward through the propeller disc. Wing guns for this model
have been reported but not confirmed. "Nate's" armament is believed to be the
same as "Oscar's," although it is reported that a second 7.7-mm gun is substituted, on
some occasions, for the 12.7-mm.
Other Japanese fighters less frequently encountered include "Perry," "Claude," and "Dick." So
far as known, these are little used at the present time. In addition to these fighters of
native Japanese design, it is known that the Japanese Air Force has in operation a small
number of Messerschmitt 109 E fighters. Whether these are copied from German models
or obtained intact from Germany is not known. Up to the present, they have been
encountered only in small numbers.
It is well to bear in mind that Japanese fighter aircraft appear to be used with minor
alterations by both the Army and Navy Air Services. "Zeke" and "Hap," although used
prominently by the Navy, have been reported in operation with Army units
also. Likewise, "Nate" and Oscar," which have been reported most frequently in use
by the Army, have, upon occasions of emergency, been used by the Naval Air Service.