The Imperial Army's Carriers
Even though Classic Wargames aren't the usual
119694_avalanche Press products, we do hope to maintain
our tradition of including unusual historical
units, vehicles or ships in them.
War at Sea: Leyte Gulf definitely
follows in this path. Just as Bomb
Alley has a German helicopter carrier
and helicopter, so does Leyte Gulf boast
not one but two sent to sea by the Japanese
Army. That's correct — not the Imperial
Navy, but the Army.
The Japanese services fought a nasty bureaucratic
war throughout the period from the end of
World War I until Japan's surrender in 1945.
Japanese generals became disenchanted with
what they saw as the Navy's inability and
unwillingness to do enough to supply Army
garrisons on isolated Pacific islands.
They started by purchasing civilian freighters
for use as transports, but by the middle of
the war they had gone even further. The Army
laid down a class of transport submarines
to help run supplies to the islands, and to
help protect its surface fleet it assigned
a pair of amphibious assault carriers (themselves
a radical concept) to escort duty.
These two ships, Akitsu Maru and
Nigitsu Maru, had been laid down
as passenger liners and converted to landing
ships by the Army. They had stern doors for
launching their 20 landing craft, and short
flight decks as well.
Originally these had been intended to fly
off aircraft that would then land at airfields
captured by the landing forces. But by 1944,
when these ships were commissioned, the Japanese
Army was no longer doing much capturing. However,
the Army had an aircraft available that could
make full use of the short flight decks for
take-off and for landing, and promised to
show good qualities in anti-submarine warfare
The Kayaba Ka-1 autogyro was based on an
American design, imported to Japan in 1938.
An autogyro is a hybrid of helicopter and
airplane; while it has a rotor blade chopping
overhead, it also has a propellor. Juan de
la Cierva, a Spanish engineer, invented the
concept and flew an autogyro over the English
Channel in 1923. But the autogyro did not
gain widespread acceptance.
The Army liked the craft's short take-off
span, and especially it slow maintenance requirements.
In 1941 production began, with the machines
assigned to artillery units for spotting.
These carried two crewmen: a pilot and a spotter.
In its ASW configuration, the spotter gave
way to two depth charges. Ka-1 anti-submarine
aircraft operated from shore bases as well
as the two small carriers. They appear to
have had one successful submarine sinking.
Had the Army and Navy been able to cooperate
on the program, the Ka-1 could have been made
devastatingly effective: the Navy had developed
a precursor of what later navies would call
"dipping sonar," perfectly suited
to autogyro use.
American submarines eventually sank both
of the carriers.