The design of the Lockheed L-188 Electra began in 1954, and in the following year the company received a launching order from American Airlines.

By the first flight, 144 were already on order. The prototype, first flown on 6 December 1957, was a low-wing monoplane of conventional configuration with retractable tricycle landing gear and powered by four Allison 501D-13, 501D-13A or 501D-15 turboprop engines. Standard accommodation was for 66 to 80 passengers, but a high-density arrangement was available optionally to seat 98.

Several crashes occurred in 1959 that caused Lockheed Corp. to make a few improvements including a stronger wing structure and engine nacelles plus thicker wing skins.

Built initially as the L-188A, the Electra became available also as the longer-range L-188C with increased fuel capacity and operating at a higher gross weight. A total of 170 had been built when production ended unexpectedly early as a result of passenger loss of confidence in the type after two had disintegrated in flight, and by the time remedial modifications had been, incorporated customer airlines were interested in turbojet- rather than turboprop-powered aircraft. About half of the total built remained in service in 1992, many of them converted by Lockheed Aircraft Service for convertible passenger/cargo or all-cargo use.

Gallery

L-188A Electra
Engines: 4 x Allison 501D-13, 2796kW / 4600 hp
Propellers: Hamilton Standard
Max take-off weight: 51256 kg / 113001 lb
Empty weight: 26036 kg / 57400 lb
Wingspan: 30.18 m / 99 ft 0 in
Length: 31.85 m / 104 ft 6 in
Height: 10.01 m / 32 ft 10 in
Wing area: 120.77 sq.m / 1299.96 sq ft
Cruise speed: 652 km/h / 405 mph
Ceiling: 8655 m / 28400 ft
Range: 3541 km / 2200 miles
Crew: 5
Passengers: 44-98

Engines: 4 x 4,050 h.p. Allison 501 D15 turboprop.
Length 104.5 ft. (31.81 m.)
Wing span 99 ft. (30.18 m.)
Weight empty 57,300 lb. (25,990 kg.)
MTOW: 113,000 lbs (51,227 kg).
Pax cap: 99.
Max cruise 405 m.p.h. (650 km.p.h.)
Ceiling 28,400 ft. (8,655 m.)
Range 2,770 miles (4,458 km.) with 18,000 lb. (8,165 kg.) payload
Cabin width: 10 ft 8 in.
Takeoff run 4,720 ft
Landing roll 4,300 ft

Lockheed’s C 130 Hercules was designed to meet a specification issued by the USAF Tactical Air Command in 1951.

The prototype C-130 flew on August 23, 1954. Production models were delivered from 1956 and remained in production in 1999 in latest C-130J form with fully integrated digital avionics, advanced engines and propellers, and other improvements.

Older espionage-variants of the Hercules, the C-130A-II and the C-130B-II, had been noted at Rhein-Main around 1955. The metal-coloured aircraft, which externally were no different from the freighters operating regularly from Rhein-Main, belonged to the 7406th Combat Support Squadron.

The RC-130 carried out COMmunications INTelligence (COMINT) for the USAF in Europe under the auspices of the National Security Agency. The RC-130s flew not only to West Berlin (Operation Misty Creek), but also on eavesdropping missions along the Iron Curtain and the borders of other countries, including the Middle East.

One of the C-130A-IIs from Rhein-Main lost its bearings in the early hours of 2 September 1958 during a COMINT mission for NSA along the Turkish-Soviet border, and was shot down near the town of Jerevan in Armenia by a group of five MiGs. Of the 17 crew and NSA eavesdropping specialists six lost their lives. What happened to the remaining eleven is still unknown in Washington. The Soviet Union has never admitted that the RC-130, which took off from the Turkish airfield at Incirlik, was shot down.
In turn, the US Government has never admitted that the Hercules in Armenia was on a reconnaissance flight. The purpose of the flight was stated to be ‘a study of the propagation of radio waves’. Washington released for publication the radio transmissions, received by an American listening post in Turkey, between the MiG pilots and a Soviet Ground Control Interception station, relaying speech from shortly before to shortly after the attack. There was no admission from the Soviets.

The 1958 Ground Proximity System uses a cargo hook dangling from the open tail door which snares a ground cable, which pulls cargo out. Up to 13,000 lb can be pulled out.

In December 1963 Lockheed was building 15 Hercules a month, with almost 600 delivered already.

Lockheed C-130 Hercules Article

In June 1965 it was reported that Malaysia protested to the US that C-130s operated by the Indonesia AF dropped para-troopers on Malaysian soil. The US had sold ten C-130s to Indonesia in 1960 for non-military use, but cut-off supplies of spare parts in 1964 when Indonesia had violated the agreement.

In 1967 Lockheed rebuilt the company’s C-130 demonstrator to the stretched L-100-20 civil freight version. The main change was the addition of a 100in fuselage insert.

It was reported in 1964 that the RCAF had bought 16 C-130E, with deliveries to be spread over a year, at $55 million including spares. The RCAF were then operating four C-130B.

C-130 in RAF Service

The four-turboprop Hercules tactical transport is available in advanced C-130H and stretched C-130H-30 versions. The latter is 4.5m (l5ft) longer than the C-130H, and has a 16.8m (56ft)-long cargo compartment, which can accommodate seven cargo pallets. The C-130H-30 can carry 128 troops or 92 paratroops, compared with 92 and 64 respectively in the standard C-130H. Similarly, the H-30 can lift 97 stretchers in the medevac role instead of the 74 of the C-130H. The RAF’s ‘stretched’ C.Mk 3 carries up to 128 troops, 92 paratroops, or freight. The C-130J C.4 being longer than the C.5.

Electronic warfare versions of the Hercules include the EC-130H Compass Call of the USAF and the EC-130Q TACAMO of the USN.

On 21 March 1973, Mirage aircraft of the Libyan Air Force attacked an RC-130 from the 7406th CSS at Rhein-Main which was eavesdropping along the coast of Egypt and Libya, The NSA operators on board the Hercules heard via their headsets that the Mirages were ordered to shoot down the four-engined American aircraft. The pilot, who was warned, managed to evade the stream of bullets from the Libyan jet fighters by flying into cloud. According to the Pentagon the attack took place about 80 miles / 130 km from the Libyan coast. As late as 1973 Washington was unable to confirm that the RC-130 was on an electronic reconnaissance flight. It did become known that the Americans were using Hellinik airfield near Athens as the start and finish for their spying flights.

The RAF operated the C 130K Hercules C Mk.1 and Hercules C Mk.1(P) (for probe).

Lockheed Martin delivered fully configured KC-130J tanker aircraft to the United States Marine Corps. Using wing and external tanks, the KC-130J has a 57,500-lb (8,455 US gallon) fuel off-load capability while performing a 500-nm radius mission, compared with 38,000 lbs (5,588 US gallons) for the KC-130Fs. The aircraft is also configured to accept a fuselage tank if desired, adding another 24,392 lbs (3,600 US gallons) of fuel to a mission. The aircraft use the probe-and-drogue configuration.

The ‘air snatch’ HC 130H, was used by the USAFs Aerospace Rescue and Recovary Service. It has scissor like folding probes on the nose designed to make pick ups from the ground or in mid air, by using the probes to engage parachute lines or balloon cables attached to the man or equipment to be recovered. First flown on 8 December 1964.

The MC-130E Combat Talon I and MC-130H Combat Talon II provide infiltration, exfiltration, and resupply of special operations forces and equipment in hostile or denied territory. Secondary missions include psychological operations and helicopter and vertical lift air refuelling.

Both aircraft feature terrain-following and terrain-avoidance radars capable of operations as low as 250 feet in adverse weather conditions. Structural changes to a basic C-130 include the addition of an in-flight refuelling receptacle and strengthening of the tail to allow high speed/low-signature airdrop. Their navigation suites include dual ring-laser gyros, mission computers, and integrated global positioning system. An extensive electronic warfare suite enables the aircrew to detect and avoid potential threats. If engaged, the system will protect the aircraft from both radar and infrared-guided threats.

Both the MC-130E and MC-130H are equipped with aerial refuelling pods to provide in-flight refuelling of special operations forces and combat search and rescue helicopters and vertical lift assets.

The primary difference between the MC-130E and MC-130H involves the degree of integration of the mission computers and avionics suite. The Combat Talon I was conceived originally and developed during the 1960s, and although extensively upgraded in the 1980-90s it still features analog instrumentation and does not fully integrate the sensors and communications suites. The Combat Talon II, designed in the 1980s, features an integrated glass flight deck which improves crew coordination and reduces the crew complement by two.

The MC-130E Combat Talon first flew in 1966 and saw extensive service in Southeast Asia, including the attempted rescue of Americans held at the Son Tay prisoner-of-war camp in 1970. Also, the MC-130E landed in the Iranian desert in April 1980 in support of Operation Eagle Claw, the attempt to rescue American hostages held by Iran.

The MC-130E saw combat in Grenada in 1983, delivering U.S. Army Rangers to Point Salinas Airfield in the opening moments of Operation Urgent Fury, and subsequently performing psychological operations leaflet drops. In 1989 they led the joint task force for Operation Just Cause in Panama, helping to seize the airfield at Rio Hato.

In 1990, MC-130Es were employed in Operation Desert Storm, where they dropped 11 BLU-82 15,000-pound bombs and more than 23 million leaflets in a highly effective effort to encourage Iraqi soldiers to surrender. They also conducted numerous aerial refuelling of special operations helicopters with combat search and rescue operations.

The MC-130H Combat Talon II first arrived at Hurlburt Field, Fla., June 29, 1992, and after acceptance testing, began official flying operations Oct. 17, 1992. Since then, the MC-130H has played a role in AFSOC operations including the evacuations of non-combatant Americans and other civilians from conflicts in Liberia in 1996. Also, in 1998, a Combat Talon II aircrew was awarded the Mackay Trophy for the involvement in the evacuation of civilians from the Republic of the Congo (1997); and they participated in combat operations in the Balkans during Operation Allied Force.

In 2001, MC-130Hs were employed to seize an airfield in southern Afghanistan delivering U.S. Army Rangers to commence ground operations in Operation Enduring Freedom and later in 2003, the MC-130H was the first US aircraft to land at Bagdad International to initiate missions supporting Operation Iraqi Freedom. Since Oct 2001, both aircraft have been used extensively in Operations Enduring, Operation Enduring Freedom-Philippines, and Iraqi Freedom in a variety of roles.

In 2001 10 MC-130E were operational with the Reserves, and 20 MC-130H with the Active force.

One of the measures considered for a second hostage rescue attempt in Iran was a project to develop a “Super STOL” aircraft, to be flown by Combat Talon crews that would use a soccer stadium near the US Embassy as an improvised landing field. Called Credible Sport, the project acquired three C-130H transports from an airlift unit in late August 1980, one as a test bed and two for the mission, and modified them on an accelerated basis.

Designated as the XFC-130H, the aircraft were modified by the installation of 30 rockets in five sets: eight firing forward to stop the aircraft, eight downward to brake its descent rate, eight rearward for takeoff assist, four mounted on the wings to stabilize them during takeoff transition, and two at the rear of the tail to prevent it from striking the ground because of over-rotation. Other STOL features included a dorsal and two ventral fins on the rear fuselage, double-slotted flaps and extended ailerons, a new radome, a tailhook for landing aboard an aircraft carrier, and Combat Talon avionics, including a TF/TA radar, a defensive countermeasures suite, and a Doppler radar/GPS tie-in to the aircrafts inertial navigation system.

Of the three aircraft, only one received full modification. The program abruptly ended when it crashed during testing on October 29, 1980, and international events soon after rendered another rescue attempt moot.

The C-130J-30 is a stretched variant and is 15 ft longer and can carry two extra cargo pallets compared to C-130H (30% more). A key to the C-130J-30’s increased performance is a mission computer linked to the four new, electronically controlled (by Lucas Aerospace’s FADEC (full authority digital electronic control) system) Allison AE-2100D3 turboprops. Flat rated to 4,691 shp (down from 6,148 shp), the engines still generate 29 percent more thrust and they are 15 percent more fuel-efficient than the E model’s. An all-composite six-blade Dowty Aerospace R391 propeller is lighter and has fewer moving parts than previous Hercules C-130 propellers. Lockheed-Martin were to develop and produce six WC-130J weather reconnaissance aircraft.

The AC-130 is the gunship variant of the C-130 Hercules. The first flight of the AC-130A was in 1967. The missions of the AC-130 are: close air support, air interdiction and armed reconnaissance, perimeter and point defense, escort, drop and extraction zone support, forward air control, limited command and control (c2), and combat search and rescue (CSAR).

The AC-130A Spectre is similar to the C-130 in terms of external dimensions. It is 97 feet, 9 inches long, 38 feet, 3 inches tall, and has a wingspan of 132 feet, 7 inches. Originally, the AC-130A did not have the capability to refuel in flight. With a full load, these AC-130As had a range of 2450 miles. However, once modified with aerial refueling capabilities, the range was limited only by crew endurance. The AC-130A was sent to Vietnam on September 20, 1967, and flew its first mission one week later. The AC-130A destroyed over 10,000 enemy vehicles during the course of the Vietnam War. The last AC-130A was retired on September 10, 1995.

Between November 1968 and November 1989, only four, and later six, AC130 gunships were operating over the Trail, pending delivery of more advanced ‘Spectres’.

The first AC-130 gunship had arrived in Vietnam for field trials in September 1967, and its success led to the decision to modify more of the type. However, the Air Force could not spare any of its C-130 fleet, they were all needed for airlift duties throughout South-East Asia. Seven early-model C-130s were available though, and the first of these was converted to gunship configuration by June 1968; combat operations began with four aircraft in October 1968.

The AC-130 was armed with four 7.62mm minigun modules and four 20mm gatting cannon. Two of each were mounted forward of the main landing gear on the port (left) side of the aircraft and two each aft of the gear. In addition, a Night Observation Device (NOD) or Starlite Scope was carried – a sophisticated piece of equipment which enables the user to see targets on the ground by utilizing the available star or moonlight. The NOD and a primitive infra-red sensor were fitted to the port side of the aircraft and a bread-board computer was also carried to co-ordinate all the variables involved in a side-firing weapons system. These early AC-130s were operated by the newly formed 16th Special Operations Squadron at Ubon Royal Thai Air Force Base, and the Commander of Spectre Crew Number One was Lieutenant Colonel William Schwehm.

The AC-130H (also Spectre), which initially worked with the AC-130A, replaced it in 1995. The H-model has computers which can tell whether a target is friendly or not, thus, reducing the amount of casualties due to friendly fire. In the Persian Gulf War, one AC-130H was lost, along with all 14 crew.

The AC-130U Spooky is an advanced gunship. It can support special operations forces, in addition to its primary mission (gunship). It has a fire control system, which is capable of attacking two targets at once. With advanced computers, all guns can be slaved to computers if the need should arise.

The first RAAF C-130J-30 Hercules II, A97-464, was officially handed over at RAAF Richmond on 7 September, 1999. The first of 12 to replace the 37 Sqn C-130Es.

During 1964 a C-130E Hercules flew 25 hr 1 min 8 sec without landing as a prelude to FAA certification for civilian cargo use. The red, white, and blue aircraft was built as a cooperative venture by Lockheed and 57 suppliers of engines, parts, and systems for C-130’s. Once airborne it flew the endurance run at 140 kt on two engines.

Hercules commercial transports have an L 100 series designation. Largest of these, the L.100 30 entered service in 1970, can lift a maximum payload of more than 23 tons.

1,814 aircraft of all versions had been deliv¬ered by June 1987. Total Hercules sales had reached 1,845 by June 1987.

In July 1997, the company set-up then included Lockheed Martin Aeronautical Systems tasked with production and support of the C-130.

In 2005 an RAAF C-130J operating in Iraq was fired on by a surface-to-air missile over Baghdad and forced to deploy counter-measures and take evasive action. The Hercules was not damaged.

By 1999 well over 2,200 Hercules, still in production, had been built.

Hawkins & Powers enveloped civil conversions of of C-130 and P2V-7 under TC A19NM, A30NM, and A34NM in the Restricted category as borate bombers for forest fire control.

Gallery

C 130 Hercules
Length : 97.736 ft / 29.79 m
Height : 38.255 ft / 11.66 m
Wing span : 132.612 ft / 40.42 m
Max take off weight : 175032.9 lb / 79380.0 kg
Max. speed : 330 kts / 611 kph
Service ceiling : 22638 ft / 6900 m
Range : 4083 nm / 7562 km
Engine : 4 x Allison T56-A7A, 3995 shp
Crew : 4+92
Armament : 8862kg Freight

C-130A
Engines: 4 x Allison YT56-A-11 turboprop, 3,750 e.h.p.
Wingspan: 132 ft 7 in
Length: 97 ft 9 in
Basic weight: 67,000 lb
Loaded weight: approx. 124,200 lb.
Max fuel: 40,000 lb
Cruise: 320 mph
Max. speed: approx. 400 m.p.h.
Typical range: 2,900 miles at 350 m.p.h. at altitude, with 40,0001b. payload
Armament: None
Crew: 5

C-130E
Wing span: 132 ft 7 in (40.41 m)
Length: 97 ft 9 in (29.78 m)
Height: 38 ft 3 in (11.66 m)
Engines: 4 x Allison, 4050shp
Max TO wt: 175,000 lb (79,380 kg)
Max level speed: 384 mph ( 618 kph).

C-130H Hercules
Engine: 4 x Allison T56-A-15, 4,190 shp
Installed thrust: 13,440 kW
Propellers: 4-blade
Span: 40.4 m
Length: 29.8 m
Wing area: 162 sq.m
Height: 11.7m
Empty wt: 34,686 kg
Max AUW: 70,450kg
Maximum Alternate AUW: 79,380 kg
Payload: 19,365 kg
Cruise speed: 595 kph
Initial ROC: 415 m / min
Ceiling: 10,060 m / 40,000 ft
T/O run: 1091 m
Ldg run: 518 m
Fuel internal: 36,636 lt
Range 14,000kg payload: 5,100km
Range with 19,765 kg: 3790 km
Ferry range: 7400km
Capacity: 92 pax or 64 paratroopers
Medivac config: 74 stretchers
Freight config: 6 cargo pallets
Air refuel: Yes
Crew: 2 pilots, 1 navigator, 1 flight engineer, 1 loadmaster.

Lockheed Martin C-130J Hercules
Engine: 4 x Allison AE2100D3 turboprops, 4,590 shp
Propellers: 6-blade variable-pitch
Length: 34.37m
Height: 10.1m
Wingspan: 132.579 ft / 40.4m
Wing area: 1745.06 sq.ft / 162.12 sq.m
Maximum weight: 79,380kg
Maximum payload: 19,500kg
Max. speed: 348 kts / 645 kph
Normal operations cruise: 625km/h
Initial climb rate: 2106.30 ft/min / 10.70 m/s
Range 18,155kg payload: 5,100km
Ceiling: 35,000 ft
Crew: Two pilots, loadmaster
Accommodation: 128 troops / 74 paratroops / 74 stretcher, two attendants

C-130J-30
Engines: 4 x Rolls-Royce Allison AE 2100D3, 4591 shp.
Props: Dowty R391 6 blade composite.
Cruise: 348 kts.
Range: 3262 sm (with 40,000 lb payload).
Max payload: 41,790 lbs.
MTOW: 155,000 lbs.
Ceiling: 29,000 ft.

EC-130H
Engines: 4 x Allison T56-A-15 turboprop, 4508 ehp (3362 kW).

EC-130Q
Engines: 4 x Allison T56-A-15 turboprop, 4508 ehp (3362 kW).

HC 130H
Engines: 4 x Allison T56 A 15 turboprop, 4,500 esh.
Prop: 13 ft 6 in (4.11 m) dia 4 blade.
Wing span: 132 ft 7 in (40.41 m).
Length: 98 ft 9 in (30.10 m).
Wing area: 1,745 sq ft (162,12 sq.m).
Gross weight: 155,000 lb (70,310 kg).
Max speed: 384 mph (618 km/h).
Typical range: 2,450 miles (3,945 km).
Crew: 10.

LC-130H3
Engines: 4 x Allison T56-A-15 turboprop, 4508 ehp (3362 kW).
Fuel cap: 64,654 lbs.
MTOW peacetime: 155,000 lb
MTOW wartime: 175,000 lbs.
Cargo bay: 12x3x3m.
Payload: 12,270 kg.

MC-130E
Primary Function: Infiltration, exfiltration, and resupply of special operations forces
Engines: Four Allison T56-A-15 turboprop, 4,910 shaft horsepower
Wingspan: 132 feet, 7 inches (40.4 meters)
Length: 100 feet, 10 inches (30.7 meters)
Height: 38 feet, 6 inches (11.7 meters)
Speed: 300 mph
Load: 53 troops, 26 paratroopers
Ceiling: 33,000 feet (10,000 meters)
Maximum Takeoff Weight: 155,000 pounds (69,750 kilograms)
Range: 2,700 nautical miles (4,344 kilometers)
Crew: Two pilots, two navigators and an electronic warfare officer (officers); flight engineer, radio operator and two loadmasters (enlisted)
Date Deployed: 1966
Unit Cost: US $75 million

MC-130H
Primary Function: Infiltration, exfiltration, and resupply of special operations forces
Contractor: Lockheed
Engines: Four Allison T56-A-15 turboprop, 4,910 shaft horsepower
Wingspan: 132 feet, 7 inches (40.4 meters)
Length: 99 feet, 9 inches (30.4 meters)
Height: 38 feet, 6 inches (11.7 meters)
Speed: 300 mph
Load: 77 troops, 52 paratroopers or 57 litter patients
Ceiling: 33,000 feet (10,000 meters)
Maximum Takeoff Weight:155,000 pounds (69,750 kilograms)
Range: 2,700 nautical miles (4,344 kilometers)
Crew: Two pilots, a navigator and electronic warfare officer (officers); flight engineer and two loadmasters (enlisted)
Date Deployed: June 1991
Unit Cost: US$155 million

L-100-30
Engines: 4 x Allison, 4050shp
Wing span: 132 ft 7 in (40.41 m)
Length: 112 ft 8.5 in (34.35 m)
Height: 38 ft 3 in (11.66 m)
Max TO wt: 155,000 lb (70,308 kg)
Max level speed: 377 mph ( 607 kph).

Hercules C.Mk.1
Wing span: 132 ft 7 in (40.41m)
Max cruise: 386 mph (621 kph).

AC-130H
Engines: 4 x Allison T56-A-15 turboprop, 4,910 shp
Length: 97 ft, 9 in / 29.8 m
Height: 38 ft, 6 in / 11.7 m
Wing span: 132 ft 7 in / 40.4 m
Max Take-Off Weight 155,000 lb / 69,750 kg
Max level speed SL: Mach 0.4 / 300 mph (482 km/h)
Service ceiling: 25,000 ft / 7,576 m
Armament: two 20mm guns, one 40mm cannon and one 105mm cannon;
Crew: Five officers (pilot, co-pilot, navigator, fire control officer, electronic warfare officer) and eight enlisted (flight engineer, TV operator, infrared detection set operator, loadmaster, four aerial gunners)

AC-130U
Engines: 4 x Allison T56-A-15 turboprop, 4,910 shp
Length: 97 ft, 9 in / 29.8 m
Height: 38 ft, 6 in / 11.7 m
Wing span: 132 ft 7 in / 40.4 m
Max Take-Off Weight 155,000 lb / 69,750 kg
Max level speed SL: Mach 0.4 / 300 mph (482 km/h)
Service ceiling: 25,000 ft / 7,576 m
Armament: one 25mm gun, one 40mm cannon and one 105mm cannon;
Crew: Five officers (pilot, co-pilot, navigator, fire control officer, electronic warfare officer) and eight enlisted (flight engineer, TV operator, infrared detection set operator, loadmaster, four aerial gunners)

A government advisory group in 1959 recommended that a full-size V/STOL aircraft was required, with specific requirements for the Navy and Army. Previous VTOL programs had been built to illustrate a particular principle, but few of these concepts had any operational military capabilities. With the XC-142, it was decided that this system would be tested in an operational environment. It was decided that the system would fulfill requirements for all three military services. The first tri-service VTOL.
In 1961, a Request for Proposal was released, and in September, the proposal from Vought-Hiller-Ryan was announced as the winner. It was also announced that the Air Force would manage the program with the cost of the program to be shared equally by each of the services.
Vought Aeronautics Division of Ling-Temco-Vought was the prime contractor, with Hiller and Ryan serving as the major subcontractors. Vought subcontracted the design and fabrication of the empennage, aft section, engine nacelles, and wing to Ryan. The overall transmission system and selected components were subcontracted to Hiller, which was also responsible for the flap and aileron fabrication.
The XC-142 grossed out at about 16900kg loaded with an empty weight of about 10780kg. The plane had a fuselage length just exceeding 17.7m, with a maximum height of 7.9m and a sizable wing span of 20.6m. The model carried a single tall vertical tail that provided 12sq.m of area. The wings carried large trailing double-slotted flaps the entire length of each wing and were mounted high on the fuselage.
The fuselage was designed to carry significant cargo, with the cargo compartment being 9.15m in length with a 2.1m height and width. That volume equated to about 32 full-loaded troops and gear, or four tons of cargo. In addition to that capability, there was also the ability to carry 370 litres of fuel. There was also a planned capability for auxiliary tanks which would greatly add to the range.

Power consisted of four 3080hp General Electric T64-GE-1 engines, mounted in nacelles on the wings, which were all cross-linked together. Each drove a four-bladed 4.7m Hamilton-Standard fiberglass propeller, the tips of each practically overlapping each other.
Later in the program, Hamilton Standard would provide an improved version of the propeller using the 2FF blade design, which featured a wider planform, rounded tips, and a more pronounced twist than the earlier 2EF blades. The goal of the new design was to improve aerodynamic load distribution and overcoming a static load problem.
The four engines also drove a fifth propeller, a three-bladed fiberglass type, in the tail through an interconnected gear and shaft train. Therefore, power was available to turn all five propellers when one, two, or three engines were shut down. The tail propeller rotated in a horizontal plane and was declutched and braked for cruise flight.
Through cross-shafting gearboxes, the rotation from each engine was brought together at the top of the fuselage. The power was then sent back to the tail rotor through a tail propeller shaft, into the tail propeller gearbox, and on to the variable pitch tail propeller.
The propulsion system of the XC-142 was over powered. The plane could lose an engine on take-off and still clear a 15.25m barrier in 122m carrying a 4500kg payload. Also, with all engines operating, the plane had a rate of climb at sea level of 34.5m/s. On a hot day, even with an engine out, the XC-142 showed a climb rate of 17.8m/s.
Roll control was by differential propeller pitch. Pitch control was accomplished by the eight-foot, three-bladed variable pitch tail rotor. Yaw control was provided by ailerons powered by propeller slipstream deflection, actually a second VTOL concept being employed in the XC-142.
The craft main lift system in the wing was capable of rotating through 98 degrees instead of the expected straight-vertical position. The wing tilt mechanism consisted of two screw-jack actuators driven by a centrally-located hydraulic motor. The tilt was controlled by a variable rate switch on each collective lever, or by a constant rate switch. This allowed the plane to hover in a stationary mode in a tailwind condition.
The trailing edge of the wings carried three-section, double-slotted flaps in three sections, with the center and outboard sections operated also as ailerons. The flaps were programmed automatically with changing wing tilt, although the pilot had an override capability. Leading edge slats were used for stall suppression, and were mounted outboard of each engine nacelle and operated automatically as a function of flap position. The vertical tail was operated as a standard rudder-and-fin set-up, which supported the slab-type unit horizontal tail assembly.
A fully-powered irreversible type with artificial feel forces and powered by dual independent hydraulic systems was fitted. Dual cockpit controls, consisting of conventional rudder pedals, control sticks, and collective levers for all take-offs and landings, provided the highest technology of the system.
The tail rotor was rigged to fold to the port side to reduce the storage length and protect against damage during a loading operation.

The first XC-142 was rolled out in early 1964 with its first conventional flight being made in September 1964, its first hover three months later, and the first transition from hover to horizontal flight and return on 17 January 1965. The Air Force extensively tested the XC-142’s capabilities with cargo flights, cargo, and paratrooper drops, along with desert, mountain, rescue, and carrier operations.

In 1966, one of the XC-142s passed operational tests to prove the model in carrier operations. In quick succession, the plane accomplished 44 short take-offs and landings, along with six vertical take-offs and landings from the USS Bennington.

The carrier trails were accomplished using the number five prototype, which was crewed by both USMC, Navy, and Army pilots. The flight regime covered VTOL operations at a variety of speeds, which occurred at wind conditions from 10 to 55km/h. A large variety of wings and flap tilt angles were used during the testing. Also, there were landings accomplished with three and six degree glide slopes. In an amazing demonstration, the plane negotiated a 360-degree turn within the width of the flight deck. That same year, one of the prototypes was also tested in an overwater pickup operation. The plane lifted a man from a life raft to determine its capability for rescue and recovery. A standard Navy horse collar sling was attached to 38m of cable and then lowered through a floor hatch just aft of the cockpit. The tests proved that there were no problems with effects of the propeller downwash or slipstream turbulence.

The program called for the building of five prototypes, 62-5921-5925, but cross-shaft problems, along with some operator errors, resulted in a number of hard landings causing damage to the complete fleet.

The most serious of the mishaps, resulting from a tail rotor driveshaft failure, caused three fatalities. The May 1967 accident took place near the Dallas, Texas, LTV plant and occurred in a heavily-wooded area where fire started after the impact.
The flight plan for the ill-fated prototype included a rapid decrease in altitude from 2440m to 915m, effectively simulating a pilot rescue under combat conditions. A nose-over at low altitude followed, from which the crew could not recover. The crash aircraft was XC-142 #1 which had flown 148 times at the time of the crash. The pilots on the fatal flight were Stu Madison, Charlie Jester, and John Omvig.

Other incidents included the following:

Aircraft #2 – On October 19, 1965, this craft experienced a ground loop causing extensive damage to the wing and propeller.

Aircraft #3 – On January 4, 1966, this model made a hard landing in the vertical mode. There was significant damage to the fuselage. The wing of this plane was late mated to the Number #2 for further testing.

Aircraft #4 – On January 27, 1966, an engine turbine failure caused the overriding clutch to engage, causing extensive damage to the wing, outboard aileron, the number two nacelle, aft engine shroud, and fuselage. It was later used by NASA for further research.

Aircraft #5 – ln December of 1966, a ground accident caused major damage to the fuselage, nose, wing, and propellers. The incident was caused by pilot error who failed to activate the hydraulic system, which resulted in no brakes or nose wheel steering.

The final decision on the disposition of the aircraft occurred during the Category II Operational Suitability Program, which was conducted at the Air Force Flight Test Center. The testing consisted of 113 flights, totaling 163.9 hours, which was accomplished between July 1965 and August 1967.
Three of the XC-142s also participated in a major operational test demonstration during the program, where the planes participated in demonstrations of VTOL, STOL, and movement of Jeep-mounted 106mm recoilless rifles, unloading of three-quarter ton trucks with towed 105mm Howitzers, dump trucks, and 450-kg A-22 containers.
For a typical XC-142 design mission, the plane could operate with a gross weight of 16900kg, including a four-ton payload. At that weight condition, the plane could take off vertically, cruise 370km near 480km/h, hover for ten minutes, and then land.
One of the limitations found in the plane, even though the overall test results were very positive, was an instability between wing angles of 35 and 80 degrees which was encountered at extremely low altitudes. There were also high side forces which resulted from yaw and weak propeller blade pitch angle controls.
Another XC-142 complaint was the excessive vibration and noise in the cockpit, when coupled with an excessively high pilot workload, and which presented a considerable challenge in the cockpit. The program involved 39 different pilots flying the prototypes for a total of 420 hours.

The greatest national exposure the XC-142 received during its flight test program occurred when the #4 prototype participated in the 1967 Paris Air Show.

The only remaining XC-142, #2 62-5924 / NASA522, was on display at the Air Force Museum at Wright-Patterson Air Force Base near Dayton, Ohio.

XC-142A
Crew: 2
Passengers: 24-44
Engines: 4 x General Electric T-64 turboshaft, 2095kW
Wingspan: 20.6m
Length: 17.8m
Height: 8.0m
Wing area: 49.7sq.m
Empty weight: 10250kg
Max speed: 667km/h
Ceiling: 7620m
Range with max fuel: 756km
Range with max payload: 370km