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Mitsubishi Ki-73 (Steve)

Long Range Escort Fighter Proposal

Mitsubishi Ki-73 (Steve)

Long Range Escort Fighter Proposal

OVERVIEW
SPECIFICATIONS
ARMAMENT
VARIANTS
HISTORY
MEDIA
OVERVIEW



The Mitsubishi Ki-73 made it to the design stage and no further - Allied intelligence reports assigned it the name of Steve believing it was to enter service soon.
National Flag Graphic
ORIGIN: Imperial Japan
YEAR: 1944
MANUFACTURER(S): Mitsubishi - Imperial Japan
PRODUCTION: 0
OPERATORS: Imperial Japan (cancelled)
SPECIFICATIONS



Unless otherwise noted the presented statistics below pertain to the Mitsubishi Ki-73 (Steve) model. Common measurements, and their respective conversions, are shown when possible.
CREW: 1
ENGINE: 1 x Mitsubishi Ha-203-II 24-cylinder horizontal H liquid-cooled inline piston engine developing 2,600 horsepower.
SPEED (MAX): 466 miles-per-hour (750 kilometers-per-hour; 405 knots)




ARMAMENT



ESTIMATED:
4 x 20mm cannons in wings (two per wing element)
VARIANTS



Series Model Variants
• Ki-73 "Steve" - Base Series Designation


HISTORY



Detailing the development and operational history of the Mitsubishi Ki-73 (Steve) Long Range Escort Fighter Proposal.  Entry last updated on 9/21/2015. Authored by Staff Writer. Content ©www.MilitaryFactory.com.
During May of 1943, Japanese authorities delivered a new requirement for a single-seat, single-engine long-range escort fighter to protect bomber formations from interception by Allied warplanes beginning to gain the advantage in the skies over the Pacific and Southeast Asia. The Mitsubishi Ki-73 by Tomio Kubo was one result of this requirement but the type was not furthered beyond a sole, incomplete prototype before the war's end in 1945. Kubo managed to find success with his earlier twin-engine Ki-46 "Dinah" and eventually moved on to the promising "Ki-83" twin-engine, long-range heavy fighter design of which four prototypes ultimately emerged when the Ki-73 was abandoned for good.

Rather unique for a Japanese-originated wartime fighter design was the use of a contra-rotating propeller arrangement in which two three-bladed systems were in play. These were driven by a single Mitsubishi Ha-203-II 24-cylinder, liquid-cooled "horizontal H" inline piston engine of 2,600 horsepower which was essentially two 12-cylinder engines paired and driving the twin propeller units. The rest of the overall design arrangement was conventional - the engine in the nose, a single-finned tail at rear and the cockpit set over center mass. Wings were straight monoplane appendages with clipped tips and the undercarriage was a "tail-dragger" system made fully retractable.

Issues with the early prototype form arose centering on the complex engine fit and there were growing concerns about the structure and control scheme particularly at the speeds anticipated. Eventually work on the troublesome compound engine was ended which, in turn, ended development of the Ki-73. While the Ki-73 was never formally adopted for service and never entered serial production, captured documents by the Allies - who believed the type was to come online soon - ushered in the codename of "Steve" for the series which never was.

The proposed maximum speed for the Ki-73 was 750 kilometers per hour, about 466 miles per hour, making it one fast mount aided through its powerful engine setup and contra-rotating blades. The slender, streamlined fuselage was also clean from nose to tail. Armament would have most likely been all-cannon in keeping with Japanese fighter traditions late in the war, perhaps 4 x 20mm systems buried in the wings (two units per wing).




MEDIA









Our Data Modules allow for quick visual reference when comparing a single entry against contemporary designs. Areas covered include general ratings, speed assessments, and relative ranges based on distances between major cities.

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Relative Maximum Speed Rating
Hi: 500mph
Lo: 250mph
    This entry's maximum listed speed (466mph).

    Graph average of 375 miles-per-hour.
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Unit Production Comparison
Comm. Market HI*: 44,000 units
Military Market HI**: 36,183 units
0
0

  * Commercial Market High belongs to Cessna 172.

  ** Military Market High belongs to Ilyushin Il-2.


Supported Roles
A2A
Interception
UAV
Ground Attack
CAS
Training
ASW
Anti-Ship
AEW
MEDEVAC
EW
Maritime/Navy
SAR
Aerial Tanker
Utility/Transport
VIP
Passenger
Business
Recon
SPECOPS
X-Plane/Development
A2A=Air-to-Air; UAV=Unmanned; CAS=Close Support; ASW=Anti-Submarine; AEW=Airborne Early Warning; MEDEVAC=Medical Evac; EW=Electronic Warfare; SAR=Search-Rescue