The was a one-man '' kamikaze'' aircraft developed by the Imperial Japanese Army Air Force in the closing stages of World War II in

1945 1945 marked the end of World War II and the fall of Nazi Germany and the Empire of Japan. It is also the only year in which nuclear weapons have been used in combat. Events Below, the events of World War II have the "WWII" prefix. Januar ...

. The Imperial Japanese Navy called this aircraft Tōka (藤花, " Wisteria Blossom").

Historical context

The aircraft's intended purpose was to be used in ''kamikaze'' attacks on Allied shipping and the invasion fleet expected to be involved in the invasion of Japan,

Operation Downfall Operation Downfall was the proposed Allied plan for the invasion of the Japanese home islands near the end of World War II. The planned operation was canceled when Japan surrendered following the atomic bombings of Hiroshima and Nagasaki, th ...

, which in the end did not take place. Because the Japanese High Command thought that Japan did not have enough obsolete aircraft to use for ''kamikaze'' attacks, it was decided that huge numbers of cheap, simple suicide planes should be constructed quickly in anticipation of the invasion of Japan.

Construction

The aircraft was very simple, being made from "non-strategic" materials (mainly wood and steel). To save weight, it was to use a jettisonable undercarriage (there was to be no landing), so a simple welded steel tube undercarriage was attached to the aircraft.Tsurugi closeups. Col. Scott Wille
article
/ref> This, however, was found to give unmanageable ground-handling characteristics, so a simple

shock absorber A shock absorber or damper is a mechanical or hydraulic device designed to absorb and damp shock impulses. It does this by converting the kinetic energy of the shock into another form of energy (typically heat) which is then dissipated. Most sh ...

was then incorporated. The cross section of the fuselage was circular and not

elliptical Elliptical may mean: * having the shape of an ellipse, or more broadly, any oval shape ** in botany, having an elliptic leaf shape ** of aircraft wings, having an elliptical planform * characterised by ellipsis (the omission of words), or by conc ...

as were most planes of this size and type; such a fuselage was easier to make. ''Tsurugi'' had an instrument panel with some flight instruments, rudder pedals, a joystick type control column and a place for a radio. Flight controls included both ailerons and elevators and (in production versions) flaps. The Ki-115 was designed to be able to use any engine that was in storage for ease of construction and supply, and to absorb Japan's stocks of obsolete engines from the 1920s and 1930s. The initial aircraft (Ki-115a) were powered by Nakajima Ha-35 radial engines. It is not known if any other engine was ever actually fitted. After testing the first production aircraft were fitted with the improved undercarriage and two rocket units. These may have assisted with take-off or may have been designed for the final acceleration towards the target.Kamikaze and the Nakajima Ki 115 Tsurugi
/ref>

Performance

The aircraft had a top speed of and could carry a bomb weighing as much as , large enough to split a warship in two. However, it was otherwise unarmed, and heavily laden with its bomb, would have been an easy target for enemy

fighter aircraft Fighter aircraft are fixed-wing military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air superiority of the battlespace. Domination of the airspace above a battlefield ...

. The controls were crude, the visibility terrible, and the performance abysmal. ''Tsurugi'' had very poor take-off and landing performance and could not be safely flown by anyone other than experienced pilots. There were fatal crashes during testing and training. However new, better versions with improved controls and better visibility were under intensive development. The Japanese High Command had plans to construct some 8,000 per month in workshops all across Japan. The war ended before any flew in combat. Individually, they would have been rather inefficient weapons, but used in waves of hundreds or thousands they could have been quite destructive.

Variants

* Ki-115 Tsurugi: Single-seat suicide attack aircraft, production version. * Ki-230: Single-seat suicide attack aircraft. projected version, none built.

Surviving aircraft

Of the 105 examples produced, two airframes are known to exist. One example of the Ki-115 on loan to the Pima Air & Space Museum in Tucson, Arizona from the

National Air and Space Museum The National Air and Space Museum of the Smithsonian Institution, also called the Air and Space Museum, is a museum in Washington, D.C., in the United States. Established in 1946 as the National Air Museum, it opened its main building on the Nat ...

. Another, once displayed as a

gate guardian A gate guardian or gate guard is a withdrawn piece of equipment, often an aircraft, armoured vehicle, artillery piece, or locomotive, mounted on a plinth and used as a static display near to and forming a symbolic display of "guarding" the main ...

at Yokota Air Base, was since 1952 turned over to Japanese authorities and is reportedly at a Japanese museum.

Specifications (Ki-115a)

References

;Notes ;Bibliography * (new edition 1987 by Putnam Aeronautical Books, .) * Gunston, Bill. ''The Illustrated Encyclopedia of Combat Aircraft of World War II'' London: Salamander Books, Ltd., 1978. .

External links

{{Imperial Japanese Navy official aircraft names Ki-115, Nakajima Ki-115, Nakajima Ki-115 Single-engined tractor aircraft Low-wing aircraft Aircraft first flown in 1945