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Republic XF-103 (Thunderwarrior)

United States (1956)
Picture of Republic XF-103 (Thunderwarrior) Supersonic Mixed-Propulsion Interceptor Proposal
Picture of Republic XF-103 (Thunderwarrior) Supersonic Mixed-Propulsion Interceptor Proposal Picture of Republic XF-103 (Thunderwarrior) Supersonic Mixed-Propulsion Interceptor Proposal

The XF-103 was a Republic response to the Soviet heavy bomber threat of the early Cold War years - a missile-armed, supersonic turbojet-and-ramjet-powered interceptor.


Detailing the development and operational history of the Republic XF-103 (Thunderwarrior) Supersonic Mixed-Propulsion Interceptor Proposal.  Entry last updated on 12/28/2016. Authored by Staff Writer. Content ©www.MilitaryFactory.com

Before ground-based missiles provided the basis for viable air defense systems, the "interceptor" combat aircraft was the primary counter to high-flying, long-range heavy bombers. During the 1950s, amidst the growing threat (and inherent nuclear-delivery capabilities) of Soviet jet-powered bombers, the United States Air Force (USAF) sought various solutions to the problem at hand resulting in a bewildering array of conceptual, developmental, and production aircraft to suit the role.

One development of the mid-1950s became the Republic XF-103 "Thunderwarrior" (Company Model "AP-57") which sought to fulfill a USAF requirement begun in 1949 for a supersonic, technologically-advanced, missile-armed interceptor. The nature of this requirement dictated a most aerodynamically-refined shape with swept-back wing surfaces and a powerful propulsion system beyond what was conventional for fighters of the period. The USAF program sought to combine such an air vehicle with a new Fire Control System (FCS) - the Hughes "MA-1" - and new air-to-air missile technology. The initaitve was dubbed the "1954 Interceptor" and recognized formally as "Weapon System WS-201A".

From six competing proposals came three selected submissions in 1951 in the Convair XF-102 (based on its dimensionally smaller XF-92), the Lockheed XF-104, and the Republic XF-103.The Republic entry was a sleek offering showcasing a slim, slab-sided fuselage with pointed nosecone. Smallish triangular wing mainplanes were affixed at shoulder level near midships and the trailing horizontal tailplanes were mid-mounted along the fuselage's aft sides. A single vertical fin capped the empennage and all wing surfaces were highly swept along their leading edges. The cockpit, a retractable capsule, was held at the front of the design overlooking the nose in the usual way - the capsule held the ability to be raised for ground-running and collapsed for supersonic flight. All of the weaponry would be held internally to preserve the aerodynamic qualities of the interceptor. A tricycle undercarriage would be in play consisting of a single-wheeled nose leg mounted well-aft of the cockpit floor and a pair of single-wheeled main legs installed at the fuselage between the wing mainplanes and horizontal planes. The technology aboard the aircraft allowed just one crewman to be used. The FCS held the ability to take the aircraft to the target area, track the target, and engage the target on its own. Standard armament centered on 6 x Hughes GAR-3 "Falcon" Air-to-Air Missiles (AAMs) with a battery of 36 x Folding Fin Aerial Rockets (FFARs) also carried. Alternatively the interceptor could field 4 x Hughes Falcon missiles and 2 x Nuclear-tipped AAMs.


Picture of the Republic XF-103 (Thunderwarrior) Supersonic Mixed-Propulsion Interceptor Proposal
Picture of the Republic XF-103 (Thunderwarrior) Supersonic Mixed-Propulsion Interceptor Proposal


One of the more in interesting design qualities of an already advanced aircraft became the mixed powerplant. Primary cruising thrust would be from a standard turbojet engine - the developmental Wright XJ67-W-1 - seated in tandem with another developmental offering, the Wright XRJ55-E-1 ramjet. The ramjet added supplementary power to the turbojet installation but required a minimum operating speed before it could be engaged effectively. It was estimated that the streamlined aircraft could reach speeds of Mach 3, operate at 60,000 feet altitudes, and sport a rate-of-climb of 19,000 feet-per-minute.

A shared intake vent at the belly of the aircraft fed air into the engines. The ductwork was such that it could be rerouted to feed the ramjet or turbojet and any given time. The ramjet provided much higher thrust and thusly greater operating speeds for the proposed interceptor. However, ramjet engines of the period were notoriously fuel-thirsty and only delivered efficiency beyond Mach 1 speeds.

Republic readied a mockup which was reviewed during March of 1953 and, from this, came a contract for three total prototypes in June of 1954. Because of the inherent nature of high-speed flight, in which high temperatures developed despite the cold environment, titanium would figure largely into the aircraft's construction. As titanium was never a material to prove easy to work with, this complicated the already-complex aircraft. The engines themselves faced mounting delays and the project's budget ballooned beyond comfortable levels. The 1954 Interceptor program was effectively cancelled in 1957 and the XF-103 fell to the pages of Cold War history. Meanwhile, the competing Convair XF-102 went on to have a healthy career as an interceptor along different lines - becoming the F-102 "Delta Dagger" (detailed elsewhere on this site). Similarly, the Lockheed submission went on to become the Mach 2-capable F-102 "Starfighter" and had a notable service career all its own.

The aforementioned mockup was all that was completed of the XF-103.






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: 5000mph
Lo: 2500mph
    This entry's maximum listed speed (2,600mph).

    Graph average of 3750 miles-per-hour.
City-to-City Ranges
NYC
 
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LON
 
  PAR
PAR
 
  BER
BER
 
  MOS
MOS
 
  TOK
TOK
 
  SYD
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  LAX
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  NYC
Graph showcases the Republic XF-103 (Thunderwarrior)'s operational range (on internal fuel) when compared to distances between major cities.
Aviation Era
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Useful in showcasing the era cross-over of particular aircraft/aerospace designs.
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.


Altitude Visualization
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National Flag Graphic
Origin: United States
Year: 1956
Type: Supersonic Mixed-Propulsion Interceptor Proposal
Manufacturer(s): Republic Aviation Corporation - USA
Production: 0
Global Operators:
United States
Historical Commitments / Honors:

Military lapel ribbon for Operation Allied Force
Military lapel ribbon for the Arab-Israeli War
Military lapel ribbon for the Battle of Britain
Military lapel ribbon for the Battle of Midway
Military lapel ribbon for the Berlin Airlift
Military lapel ribbon for the Chaco War
Military lapel ribbon for the Cold War
Military lapel ribbon for the Cuban Missile Crisis
Military lapel ribbon for the Falklands War
Military lapel ribbon for the French-Indochina War
Military lapel ribbon for the Golden Age of Flight
Military lapel ribbon for the 1991 Gulf War
Military lapel ribbon for the Indo-Pak Wars
Military lapel ribbon for the Iran-Iraq War
Military lapel ribbon for the Korean War
Military lapel ribbon for the 1982 Lebanon War
Military lapel ribbon for the Malayan Emergency
Military lapel ribbon for the attack on Pearl Harbor
Military lapel ribbon for the Six Day War
Military lapel ribbon for the Soviet-Afghan War
Military lapel ribbon for the Spanish Civil War
Military lapel ribbon for the Suez Crisis
Military lapel ribbon for the Vietnam War
Military lapel ribbon for Warsaw Pact of the Cold War-era
Military lapel ribbon for the WASP (WW2)
Military lapel ribbon for the World War 1
Military lapel ribbon for the World War 2
Military lapel ribbon for the Yom Kippur
* Ribbons not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective campaigns/operations.
Measurements and Weights icon
Structural - Crew, Dimensions, and Weights:
Unless otherwise noted the presented statistics below pertain to the Republic XF-103 (Thunderwarrior) model. Common measurements, and their respective conversions, are shown when possible.

Operational
CREW


Personnel
1


Dimension
LENGTH


Feet
77.10 ft


Meters
23.5 m


Dimension
WIDTH


Feet
34.45 ft


Meters
10.5 m


Dimension
HEIGHT


Feet
16.73 ft


Meters
5.1 m


Weight
EMPTY


Pounds
24,956 lb


Kilograms
11,320 kg


Weight
LOADED


Pounds
42,869 lb


Kilograms
19,445 kg

Engine icon
Installed Power - Standard Day Performance:
1 x Wright XJ67-W-3 turbojet engine developing 15,000lb of thrust; 1 x Wright XRJ55-W-1 ramjet engine developing 18,800lb of thrust.

Performance
SPEED


Miles-per-Hour
2,600 mph


Kilometers-per-Hour
4,185 kph


Knots
2,260 kts


Performance
RANGE


Miles
1,553 mi


Kilometers
2,500 km


Nautical Miles
1,350 nm


Performance
CEILING


Feet
80,052 ft


Meters
24,400 m


Miles
15.16 mi


Performance
CLIMB RATE


Feet-per-Minute
19,000 ft/min


Meters-per-Minute
5,791 m/min

Supported Weapon Systems:

Graphical image of an air launched nuclear weapon
Armament - Hardpoints (0):

PROPOSED:
36 x 2.75" (70mm) Folding-Fin Aerial Rockets (FFARs) held in an internal weapons bay.
6 x Hughes GAR-1/-3 AIM-4 "Falcon" AAMs held in an internal weapons bay.

ALTERNATIVE:
4 x Hughes GAR-1/-3 AIM-4 "Falcon" AAMs held in an internal weapons bay.
2 x Nuclear-tipped AAMs held in an internal weapons bay.
Variants: Series Model Variants
• XF-103 "Thunderwarrior" - Base Project Designation