The Douglas XB-43 Jetmaster is an American 1940s
jet-powered
Jet propulsion is the propulsion of an object in one direction, produced by ejecting a jet of fluid in the opposite direction. By Newton's third law, the moving body is propelled in the opposite direction to the jet. Reaction engines operating o ...
prototype
bomber
A bomber is a military combat aircraft designed to attack ground and naval targets by dropping air-to-ground weaponry (such as bombs), launching aerial torpedo, torpedoes, or deploying air-launched cruise missiles. The first use of bombs dropped ...
. The XB-43 was a development of the
XB-42, replacing the
piston engine
A reciprocating engine, also often known as a piston engine, is typically a heat engine that uses one or more reciprocating pistons to convert high temperature and high pressure into a rotating motion. This article describes the common featu ...
s of the XB-42 with two
General Electric
General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable energ ...
J35 engines of 4,000 lbf (17.8 kN)
thrust
Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that syst ...
each. Despite being the first American jet bomber to fly, it suffered stability issues and the design did not enter production.
Design and development
United States Army Air Forces (USAAF) leaders in the
Air Materiel Command
Air Materiel Command (AMC) was a United States Army Air Forces and United States Air Force command. Its headquarters was located at Wright-Patterson Air Force Base, Ohio. In 1961, the command was redesignated the Air Force Logistics Command wi ...
began to consider the possibilities of jet-propelled bombers as far back as October 1943. At that time, Douglas Aircraft was just beginning to design a promising twin-engine bomber designated the XB-42. Reciprocating engines powered this aircraft but they were buried in the fuselage, leaving the
laminar flow
In fluid dynamics, laminar flow is characterized by fluid particles following smooth paths in layers, with each layer moving smoothly past the adjacent layers with little or no mixing. At low velocities, the fluid tends to flow without lateral mi ...
-
airfoil
An airfoil (American English) or aerofoil (British English) is the cross-sectional shape of an object whose motion through a gas is capable of generating significant lift, such as a wing, a sail, or the blades of propeller, rotor, or turbine.
...
wing clean of any drag-inducing pylon mounts or engine cowlings. The airframe appeared ideally suited to test turbojet propulsion. Douglas confirmed the feasibility of the concept and the USAAF amended the XB-42 contract in March 1944 to include the development of two turbojet-powered XB-43 prototypes, reduced from an initial order of 13 test aircraft.
[O'Leary 1994, p. 75.]
The Douglas design team convinced the Army that modifying the XB-42 static test
airframe
The mechanical structure of an aircraft is known as the airframe. This structure is typically considered to include the fuselage, undercarriage, empennage and wings, and excludes the propulsion system.
Airframe design is a field of aerospa ...
into the first XB-43 was a relatively straightforward process that would save time and money compared to developing a brand new design. Douglas replaced the two Allison V-1710 engines with a pair of
General Electric (GE) J35 turbojets (the first American axial-flow jet engines ever used), then cut two air intakes into each side of the fuselage, aft of the pressurized cockpit. Removing the propellers and drive shafts freed enough space for two long jet exhaust ducts. Without any propellers present, there was no chance of striking the blade tips on the runway, so the entire ventral fin/rudder unit of the earlier XB-42's full four-surface
cruciform tail __NOTOC__
The cruciform tail is an aircraft empennage configuration which, when viewed from the aircraft's front or rear, looks much like a cross. The usual arrangement is to have the horizontal stabilizer intersect the vertical tail somewhere ...
was omitted. Douglas compensated for the loss of yaw stability by enlarging the dorsal fin/rudder unit.
Douglas Aircraft was keen to mass-produce the new bomber and the USAAF considered ordering 50. The company was poised to roll out as many as 200 B-43s per month in two versions: a bomber equipped with a clear plastic nose for the bombardier, and an attack aircraft without the clear nose and bombing station but carrying 16 forward-firing .50 in (12.7 mm) machine guns and 36 5 in (127 mm) rockets. Nothing came of these plans. The USAAF was already moving ahead with a new bomber, the
XB-45 Tornado, designed from the outset for turbojet power and promising major improvement in every category of performance.
Operational history
![XB-43 Color takeoff](https://upload.wikimedia.org/wikipedia/commons/d/da/XB-43_Color_takeoff.jpg)
As Douglas predicted, the work itself was not overly complex but almost two years were required to ready the aircraft for flight due to delays in obtaining the J35 powerplants.
The end of World War II caused a general slowdown within the aviation industry and GE was late delivering the engines. When they were at last installed and tested on the ground, one of the units failed catastrophically. Compressor blades exploded through the engine casing, damaging the surrounding airframe and injuring a ground technician. Another seven-month delay ensued for repairs. America's first turbojet bomber finally flew from
Muroc Army Air Base
Muroc (also, Rogers, Rod, Yucca, and Rodriguez) is a former settlement in Kern County, California in the Mojave Desert.
It was located on Rogers Dry Lake east of Edwards, at an elevation of 2283 feet (696 m).
Muroc still appeared on maps as of ...
on 17 May 1946, piloted by Douglas test pilot, Bob Brush, accompanied by engineer Russell Thaw.
Caught in a momentous technological shift, the XB-43 contributed to developing procedures for flying the new jet bombers, and it gave yeoman service testing new turbojet engines. Douglas completed the second prototype, AAF serial number ''44-61509'', flying on 15 May 1947 and delivered it to Muroc Air Force Base, California, in April 1948.
The USAAF soon replaced one J35 turbojet engine with a General Electric J47. Douglas delivered the second prototype, designated YB-43, in April 1948. That aircraft was nicknamed ''Versatile II'' by USAAF personnel. When the clear plastic nose began to crack from variations in temperature at high and low altitudes, mechanics fashioned a more durable replacement made from plywood. To keep it flying, the US Air Force cannibalized parts from the first XB-43 after it was damaged in February 1951. ''Versatile II'' flew more than 300 hours until its retirement in December 1953.
The U.S. Air Force only considered the first prototype to fall under the XB-43 designation. The second prototype, though functionally identical to the first, was designated YB-43, consistent with its status as a follow-on prototype under the Army's
designation system for aircraft. At one point, the aircraft may have also been designated as "attack" aircraft, A-43 (not to be confused with the
Curtiss XP-87, a project which started as an attack aircraft under the same designation.) The A-43 was to have eight machine guns in a solid nose replacing the bombardier's position.
Aircraft disposition
* 44-61508: destroyed when used for target practice in the desert.
* 44-61509: in storage awaiting restoration in the Restoration Hangar at the
National Museum of the United States Air Force
The National Museum of the United States Air Force (formerly the United States Air Force Museum) is the official museum of the United States Air Force located at Wright-Patterson Air Force Base, northeast of Dayton, Ohio. The NMUSAF is the ...
in
Dayton, Ohio
Dayton () is the sixth-largest city in the U.S. state of Ohio and the county seat of Montgomery County. A small part of the city extends into Greene County. The 2020 U.S. census estimate put the city population at 137,644, while Greater Day ...
. The YB-43 was turned over to the Smithsonian Institution in 1954. It was stored while awaiting restoration at the
Smithsonian's Paul Garber Facility (
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 ...
) in
Suitland, Maryland
Suitland is an unincorporated community and census designated place (CDP) in Prince George's County, Maryland, United States, approximately one mile (1.6 km) southeast of Washington, D.C. As of the 2020 census, its population was 25,839. Prio ...
. In late 2010, it was transferred, along with the sole surviving
Douglas XB-42 Mixmaster
The Douglas XB-42 Mixmaster was an experimental bomber aircraft, designed for a high top speed. The unconventional approach was to mount the two engines within the fuselage driving a pair of contra-rotating propellers mounted at the tail in a p ...
, to the
National Museum of the United States Air Force
The National Museum of the United States Air Force (formerly the United States Air Force Museum) is the official museum of the United States Air Force located at Wright-Patterson Air Force Base, northeast of Dayton, Ohio. The NMUSAF is the ...
in
Dayton, Ohio
Dayton () is the sixth-largest city in the U.S. state of Ohio and the county seat of Montgomery County. A small part of the city extends into Greene County. The 2020 U.S. census estimate put the city population at 137,644, while Greater Day ...
where they are awaiting restoration in the Restoration Hangars. Once completed, they will be displayed in the museum's Experimental Aircraft Hangar.
"YB-43 Jetmaster/44-61509."
''National Museum of the United States Air Force.'' Retrieved: 10 May 2013.
Specifications (XB-43)
See also
References
Notes
Bibliography
* Jones, Lloyd. ''U.S. Bombers''. Fallbrook, California: Aero Publishers, 1974. .
* O'Leary, Michael, ed. "America's First Jet Bomber" ''America's Forgotten Wings'', Volume 1, 1994, pp. 66–75.
* Wagner, Ray. ''American Combat Planes''. New York: Doubleday & Company, Inc., 1968. .
External links
National Museum of the United States Air Force: XB-43 Data Sheet
{{USAF bomber aircraft
Twinjets
B-43 Jetmaster
Cancelled military aircraft projects of the United States
Douglas B-43 Jetmaster
Aircraft first flown in 1946