From Wikipedia, the free encyclopedia

C-123 Provider
A United States Coast Guard HC-123B Provider.
Type	Military transport aircraft
Manufacturer	Fairchild
Maiden flight	14 October 1949
Primary users	United States Air Force United States Coast Guard

The C-123 Provider, designed originally as an assault glider aircraft for the United States Air Force by Chase Aircraft, was developed into a powered transport aircraft by the Fairchild Company, and went on to serve most notably with various armed forces in South East Asia. The aircraft itself would also be the testbed for a number of experimental versions designed at improving its Short Take-Off and Landing (STOL) capabilities, and was even developed into a bomber that was tested by the USAF.

Contents 1 Design and development 2 Operational history 3 Experimental projects 3.1 Black Spot and other special military C-123s 4 Operators 5 Specifications (C-123K Provider) 6 References 7 External links 8 Related content

The C-123 Provider was designed originally as an assault glider aircraft for the United States Air Force (USAF) by Chase Aircraft as the XCG-20 (Chase designation MS-8 Avitruc)^[1]. Two powered variants of the XCG-20 were developed during the early 1950s, as the XC-123 and XC-123A. The only difference between the two was the engine. The XC-123 used two Pratt & Whitney R-2800-CB-15 air-cooled radial engines, while the XC-123A used two General Electric J47-GE-11 turbojets, the same as those on the Boeing B-47 Stratojet. It was initially well regarded for tactical troop transport for its ruggedness and reliability and ability to operate from short and unimproved airstrips, which meant the low slung turbojets, prone to ingesting foreign objects, were dropped in favor of the more conventional option. The XC-123A had its engines replaced with R-2800s and was redesignated YC-123D.

By 1953, Henry J. Kaiser purchased a majority share in Chase Aircraft, feeling that after having completed C-119s for Fairchild under contract, he could take control of the impending C-123 contract. Two airframes were completed at Kaiser's Willow Run factory in Ypsilanti, Michigan, before personal politics led to Kaiser's being told that no further contracts would be honored with him. The C-123 contract was put up for bid, and the two completed airframes scrapped. The contract was finally awarded to Fairchild Engine and Airplane, who assumed production of the former Chase C-123B, a refined version of the XC-123.^[2]

The first recipients of C-123 aircraft would be USAF transport units, soon followed by the United States Coast Guard (USCG) who used the aircraft for search and rescue missions, and even the US Air Force Demonstration Team, the "Thunderbirds," would use C-123s for a time. The type would also be widely exported under various US military assistance programs, directly from USAF stocks.

The aircraft was nearly ignored by the USAF for service in Vietnam, but a political rivalry with the US Army and the Army's use of the CV-2 Caribou and later pre-production order for the C-8 Buffalo, led to a decision to deploy C-123s there. To compete with the well-performing CV-2, the USAF and Fairchild furthered development on the C-123 to allow it to do similar work on short runways. This additional development increased the utility of the aircraft and its variants to allow it to perform a number of unique tasks, including the HC-123B which operated with the USCG fitted with additional radar equipment for search and rescue missions and the C-123J which were fitted with retractable skis for operations in Greenland and Alaska on compacted snow runways.

By 1962, the C-123K variant aircraft was evaluated for operations in Southeast Asia and their stellar performance led the Air Force to upgrade 180 of the C-123B aircraft to the new C-123K standard, which featured auxiliary jet pods underneath the wings, and anti-skid brakes. In 1968, the aircraft helped resupply troops in Khe Sanh, Vietnam during a three-month siege by North Vietnam^[1].

A number of C-123s were configured as VIP transports, including General William Westmoreland's White Whale. The C-123 also gained notoriety for its use in "Operation Ranch Hand" defoliation operations in Vietnam. Oddly enough, the USAF had officially chosen not to procure the VC-123C VIP transport, opting instead for the Convair VC-131D.

The first C-123s to reach South Vietnam were part of the USAF's Special Aerial Spray Flight, as part of Operation Ranch Hand tasked with defoliating the jungle in order to deny rebels their traditional hiding places^[3]. These aircraft began their operations at the end of 1961. Aircraft fitted with spraying equipment were given the U prefix as a role modifier, with the most common types being the UC-123B and the UC-123K. Aircraft configured for this use were the last to see military service, in the control of outbreaks of insect-borne disease. The C-123 was also used as "jump aircraft" for U.S. Army Airborne students located at Lawson Army Airfield, located at Fort Benning, Georgia in the late 1970s and early 1980s. This aircraft was used in conjunction with the C-130 Hercules and C-141 Starlifter.

C-123s are sometimes used in movies where scenes call for large cargo aircraft, e.g. Air America and xXx. A C-123 was the main setting for the action film Con Air, as well as Operation Dumbo Drop, and was featured in a 2007 television commercial for Ford pick-up trucks which supposedly showed their braking power.

In 1954, the YC-123D, formerly the XC-123A prototype, flew in its modified state after being converted by Stroukoff Aircraft. While the most obvious change from the original XC-123A was the switch of engines, the YC-123D also had a Boundary layer control (BLC) system fitted. This system directs air from the engines at high speed over the top of the wing, making the wing act as if the aircraft is flying at a much higher airspeed. As a result, the YC-123D had a greatly reduced take-off and landing distance. Compared to the C-123B, the YC-123D could land in 755 feet instead of 1,200, and take-off with only 850 feet of runway instead of 1,950, with a 50,000 pound total weight.

In 1955 Stroukoff, under contract from the USAF, produced a single YC-123E, designed to be able to take off from any surface, and also equipped with BLC. The new aircraft also featured Stroukoff's Pantobase system, combining a ski system with a sealed fuselage and wing mounted floats, while retaining its normal landing gear. The skis worked both on snow and water, and the system effectively allowed the aircraft to land on water, land, snow or ice.

See Also YC-134

In 1956 the USAF awarded a contract to Fairchild to design an improved version of the C-123 under the designation C-136, but the contract was cancelled before the aircraft was built^[4].

At much the same time the YC-123H was under development, the product of a Fairchild modification program started in 1956 and completed in 1957. A "Jet Augmentation Program" for existing C-123Bs had been initiated in 1955 at the behest of the USAF, and in the YC-123H contract the USAF expanded it to allow the mounting of two pod-mounted General Electric CJ-610 (later developed as the military J85) turbojets. Perhaps more impressive was the new wide-track main landing gear, noticeable since the larger gear and tires required the removal of the landing gear doors. The new gear reduced the aircraft's turning radius and improved the Maximum Take Off Weight (MTOW) of the aircraft, along with being rugged enough to stand up to unimproved runways, all important factors for the C-123's mission profile. Testing both in the United States and in South Vietnam continued until the YC-123H crashed in an accident in 1963. However, many of the design improvements were carried over to the C-123K.

In 1979, the Royal Thai government, seeking to extend the life of their C-123 fleet, placed a contract with the Mancro Aircraft Company, supported by the USAF, to convert a single C-123B to turboprop powerplants. Allison T56-A-7 turboprops were used and by the time the aircraft, dubbed C-123T, was complete it had new "wet" wings, an Auxiliary Power Unit (APU) to assist with power movement of the control surfaces, and a heating system for the cargo compartments that also fed a new deicing system. Budgetary restrictions forced the Thai government to abandon the program in 1981, and with a lack of interested parties development of the C-123T stopped. However, it concluded the life of the C-123 by making it the only aircraft (at least this is claimed) to operate under jet, internal combustion and turboprop engine power, and as a glider,^[5] during its history.

During the conflict in Vietnam, a number of C-123s were modified for specialized roles. Most of these modifications were on a one- or two-aircraft level. Only the usage of C-123s as "flare ships" to illuminate targets for fixed wing gunships such as the AC-47 and AC-119G were more numerous. These aircraft, operating under the call-sign Candle were flown by the USAF's 14th Special Operations Wing.

A single C-123B was tested as a possible replacement for the Candle aircraft, with its rear loading ramp removed and replaced with a large box with 28 large lights. The airplane could continuously light a 2 mile circle from an altitude of 12,000 feet. This aircraft, under the provisional designation NC-123B was dropped because the lights, fixed to the aircraft, made it far easier for enemy gunners to track compared to the earlier flare ships.

The "Candle" aircraft had an extended life when several UC-123K's were transferred to Nakhon Phanom Royal Thai Air Force Base in Thailand. During that period, it was used as a flare ship as well as a forward air control (FAC) aircraft. The flare duties were generally used for troops in contact (TIC) while the FAC mission directed air strikes in Laos over the Ho Chi Minh trail.

Another NC-123B was used as a radio relay aircraft over the Ho Chi Minh trail, with equipment to read the signals from various sensors on the ground designed to pick up enemy truck activity.

Main article: Operation Shed Light

The most drastic modifications involve two C-123Ks in 1965, under Project Black Spot. This was to create aircraft with what was described as a "self-contained night attack capability", the modifications being completed by E-Systems of Greenville, Texas. These aircraft, designated AC-123K, had their nose section lengthened by over 50 inches. On this new nose, the AC-123K had a sensor turret fitted with a Forward Looking Infrared (FLIR) system, a Low Light Level TV (LLLTV), and a combination laser illuminator and range-finger. In addition, both aircraft were fitted with doppler radar and weapon release systems.

The AC-123K's armament consisted of a specially-built cluster system which allowed cluster bombs to be dropped through 12 ports in the aircraft's belly, with the weapon "box" loaded in the cargo area over these slots. Each of the 12 slots could be opened and closed separately, and each slot held 3 complete Cluster Bomb Units (CBU; for a total of 36). Depending on the type of CBU used, the Black Spot aircraft could carry anywhere from 2,664 to 6,372 bomblets. A version with a second box installed over the first one was tested, but it drastically cut the aircraft's effective range and was dropped.

The AC-123Ks were deployed first operationally at Osan Air Base in South Korea between August and October 1968, and operated against North Korean infiltrators approaching by boat. The operations in Korea met with a certain level of success and the AC-123Ks were transferred to South Vietnam in November 1968, mainly against the Ho Chi Minh trail and the Mekong Delta Regions. The aircraft operated until January 1969, and were returned to the United States to Hurlburt Field, Florida where in May 1969 a second round of training occurred. Four crews attended ground school in Greenville, Texas and returned to Hurlburt where they flew and became proficient in this aircraft. In October, two crews flew the aircraft to Ubon Royal Thai Air Force Base and the other two crews arrived in early November. After attending jungle survival training at Clark Air Base, missions over Laos commenced. Two missions a night were flown from Ubon with two A-1 Skyraider escorts from Nakon Phanom (NKP) flying cover and providing additional fire power. The area of responsibility for the first six months was approximately 100 nm east-southeast from NKP. After that, the area of coverage was a river in southern Laos. Missions terminated in early July and the aircraft flew to the "boneyard" at Davis-Monthan AFB, were restored to C-123K standard, then delivered to South Vietnam still wearing their camouflage and black undersides, and returned to transport duty. The Black Spot project had been successful, but had never been intended for operational use.

There is some debate about whether or not the designation AC-123K was official, but it does appear in official US government documentation, and the more-often applied designation, NC-123K appears in the same documentation in reference to the aircraft after they had been demodified (in the document it says "partially demodified") and returned to service in the transport capacity.

 Cambodia

 Republic of China

 El Salvador

 Laos

 Philippines

 Saudi Arabia

 South Korea

 South Vietnam

 Thailand

 United States

• US Air Force
• United States Coast Guard

 Venezuela

General characteristics

• Crew: 3
• Capacity: 62 passengers
• Length: 76.25 ft (23.92 m)
• Wingspan: 110 ft (33.53 m)
• Height: 34 ft (10.36 m)
• Wing area: 1,223 ft² (113.6 m²)
• Empty weight: 35,366 lb (16,042 kg)
• Loaded weight: 60,000 lb (27,000 kg)
• Powerplant:
  • 2× General Electric J85-GE-17 turbojets, 2,850 lbf (13 kN) each
  • 2× Pratt & Whitney R-2800-99W "Double Wasp" 18-cylinder radial engines, 2,300 hp (1,715 kW) each

Performance

• Maximum speed: 228 mph (198 knots, 367 km/h) with jets
• Range: 1,035 mi (899 nm, 1,666 km) combat
• Service ceiling: 29,000 ft (8,800 m)
• Rate of climb: 1,150 ft/min (5.8 m/s) without jets
• Wing loading: 49 lb/ft² (240 kg/m²)
• Power/mass (prop): 0.077 hp/lb (130 W/kg)
• Thrust/weight (jet): 0.10

• Green, William and Pollinger, Gerald. The Aircraft of the World. London: Macdonald, 1955.
• Gunston, Bill. The Encyclopedia of the World Air Power. New York: Crescent Books, 1980. ISBN 0-517-53754-0.
• ________. The Illustrated Encyclopedia of the World's Modern Military Aircraft. London: Salamander Books, 1977. ISBN 0-86101-010-8.

• Joe M. Jackson's mission in C-123 that earned him a Medal of Honor
• Page detailing the world's only C-123T "Turbo Provider" conversion

Designation sequence

• XC-120 - C-121 - C-122 - C-123 - C-124 - YC-125 - C-126

Related lists

• List of military aircraft of the United States
• List of military transport aircraft

v • d • e Lists relating to aviation
General	Timeline of aviation · Aircraft · Aircraft manufacturers · Aircraft engines · Aircraft engine manufacturers · Airports · Airlines
Military	Air forces · Aircraft weapons · Missiles · Unmanned aerial vehicles (UAVs) · Experimental aircraft
Notable incidents and accidents	Military aviation · Airliners · General aviation · Famous aviation-related deaths
Records	Flight airspeed record · Flight distance record · Flight altitude record · Flight endurance record · Most produced aircraft