Updated: Mar 22, 2022
The USAF faced a dilemma during the Korean War. While its World War II era transport aircraft, such as the Douglas C-47 Skytrain, Curtiss C-46 Commando and the Fairchild C-119 Boxcar were adequate for current demands, a transport with a larger capacity and a loading ramp was needed. The aircraft that met these requirements proved to be one of the best transport aircraft ever conceived, the Lockheed C-130 Hercules. During this blog, we'll trace the development and history of the Hercules, as well as its many adaptations.
The requirements for the new transport included a capacity of ninety-two passengers, seventy-two combat troops or sixty-four airborne troops in a cargo compartment which measured 41ft. long by 9ft. high and 10ft. wide. The C-130 was designed as a transport plane from the start, as opposed to earlier transport aircraft, such as the Douglas C-47 Skytrain, which was converted from the Douglas DC-3 airliner. While both the Boeing C-97 Stratofreighter and the Douglas C-124 Globemaster had rear and front ramps, respectively, they could only accommodate vehicles driving into or out of the plane, while the ramp of the Hercules could also be used to airdrop cargo, later including a low-altitude parachute-extraction system from which to drop armored vehicles, as well as the capability to drop large, prepared daisy cutter bombs for ground attack. Another difference between the 130 and previous military transports was its engines. The World War II designs used in Korea were powered by piston engines, while those of the Hercules were turboprops. The initial C-130s were powered by Allison T56-A-9 turboprops, specifically designed for the C-130. The T56 engine gave the 130 a greater power to weight ratio than earlier piston-engine transports in addition to a greater range over turbojet engines, since it used less fuel. However, one disadvantage of the T56 engine was the configuration of having the propeller connected to the compressor, which could result in structural damage to the plane if an engine failed. Safety devices were later designed to reduce propeller drag. The Air Force issued a General Operating Requirement (GOR) in February 1951 to Boeing, Douglas, Fairchild, Lockheed, Martin, Chase Aircraft, Northrup, North American and Airlifts, Inc. Fairchild, Martin, Northrup and North American declined to participate with Lockheed awarded the contract in July of that year after a close competition with a four engine Douglas turboprop design. The first flight of the YC-130 took place in August 1954 in Burbank, California with deliveries of the C-130A to the United States Air Force beginning in December 1956.
Not long after the C-130A entered service, the limited range of the aircraft became an issue. Though the initial design had a range of 1,100 miles, the majority of the plane's missions were at the upper end of its range limit. To surmount this, 130s assigned to the Tactical Air Command (TAC) had additional pylon-mounted fuel tanks outboard of the engines. This modification added 6,000 pounds of fuel capacity for a total of 40,000 per plane. Once the TAC aircraft became operational the pylon tanks were added to all C-130 aircraft. In late 1958, the C-130B model was delivered to USAF transport wings. The B model incorporated several improvements over the A model, such as increased fuel capacity due to auxiliary fuel tanks built into the center wing sections. C-130Bs came equipped with four-bladed Hamilton Standard propellers, which were an improvement over the three-bladed units in use on the earlier A models. The B mode also had an updated AC electrical system. Shortly after the 130Bs were introduced, an electronic reconnaissance variant of the C-130B was developed. Designated as the C-130B-II, these aircraft provided signal intelligence by the use of antennas disguised as wing fuel tanks, though they were slightly larger than the conventional fuel tanks used on other 130 aircraft. The majority of these planes featured a swept blade antenna on the upper fuselage, in addition to extra wire antennas between the vertical fin and the upper fuselage, not found on other C-130s. Radio call numbers were regularly changed on the planes as to confuse observers as to the true nature of their missions. That same year, the tanker version of the C-130 entered service. The KC-130 tankers, originally designated C130F were first flown by the United States Marine Corps (USMC) and are equipped with a removable 3,600 gal. stainless steel fuel tank carried inside the cargo compartment. The two wing-mounted hose and drogue aerial refueling pods each transfer up to 300 gal. per minute to two aircraft simultaneously, ensuring a rapid fueling cycle.
The Hercules began flying missions to Antarctica in 1960. These were flown by the LC-130, sometimes designated as the Snowbird. In a challenging environment, such as the arctic, with ever-changing weather conditions, requires a durable aircraft. The Snowbirds utilize a ski-equipped landing gear, which prevents uncontrolled sliding on snowy or icy surfaces. When the Snowbird needs to land on conventional surfaces, the landing gear can be exchanged for a traditional wheel. Another mission of the 130 is that of Hurricane Hunter. The USAAF first began flying these missions in 1943, using B-17s and B-25s, with the first organized reconnaissance formed a year later. The C-130s who flew these missions were known as WC-130s and became dedicated Hurricane Hunters by 1963, proving to be one of the most reliable weather reconnaissance aircraft. The C-130 was also one of the first aircraft to fly by JATO (Jet Assisted Take Off). Developed by Ernst Heinkel during World War II, the JATO system utilizes rockets attached to the rear of the plane to increase take off thrust. While not used in everyday situations, JATO units allow an aircraft to take off from unimproved runways requiring a shorter distance. In the early 1960's The National Science Foundation used an NCAR-130 to conduct scientific research at high altitudes. Their payload carried a variety of instruments, which measured icing, cloud properties and turbulence, as well as samples of atmospheric and oceanic
emissions. In 1963 the 130 scored a first by being the heaviest aircraft to land on an aircraft carrier. Experiments were conducted aboard the USS Forrestal in October and November of that year, with the aircraft payload gradually increasing to 30,000 lbs. The aircraft involved completed 21 unarrested full-stop landings while completing 29 touch-and-go take offs and landings. The C-130 was the largest plane to land on a carrier, as well.
Due to the configuration of its aft loading ramp and door, the 130 can carry a variety of oversized cargo, including palletized cargo and personnel, as well as armored vehicles and utility helicopters. During the Viet Nam War, the delivery of palletized loads became of prime importance in order to supply isolated artillery fire bases, surrounded by Viet Cong and North Vietnamese forces making conventional delivery nearly impossible. To surmount this, the C-130s delivered supplies and equipment to the fire bases by sliding the pallets off the rear loading ramp while the aircraft was flying near the ground at a low rate of speed. Upon touching the ground, the pallets were able to slide by skids attached underneath. The 130s also parachuted smaller loads above the fire bases during both day and night, depending upon the needs of the ground forces. Speaking of artillery, the C-130 added a new mission to its inventory during Viet Nam, that of aerial field artillery. The AC-130 gunship, known as Super Spook, flew its first fire support mission in late 1967, replacing modified C-47 (AC-47) cargo planes. The C-130s had the advantages of a larger fuel capacity, allowing more time over the target, a larger payload of ammunition, as well as a substantially bigger cabin area, accommodating radar and other electronics. In 1968, an improved version of the AC-130, the AC-130A Spectre gunship began supporting US Army special forces on the ground with armed reconnaissance and close air support. By 1969, a number of modifications to the gunship enhanced its capabilities, such as Gatling guns with an analog fire control system mounted along the left side of the airframe, in addition to 20mm rotary autocannons and 40mm Bofors cannons. By the end of the war, C-130Es had joined the fray with an active tv system to monitor ground targets, as well as the punch of a 105 mm cannon. The 130s even did some bombing during the war, dropping the BLU-82 ( Big Blue 82, Daisy Cutter) bombs into dense vegetation, wiping out sections of forests in order to prepare landing zones for Huey helicopters. The BLU-82 system consisted of 15,000 small bombs, which were released by the activation of a handle. The bomb's extraction parachute deployed and helped the bomb drift to its target before it exploded with a huge concussive shockwave. They were later used as psychological warfare tools in Desert Storm.
The C-130 also has a number of civil applications. Converted C-130 tankers have fought forest fires in the western United States for over thirty years, proving to be an effective fire control system, with no casualties to the crews involved. For twenty years, C-130 crews have participated alongside the US Coast Guard to conduct oil spill control exercises, to ensure the US military has a credible response, should such a disaster happen. Hercules crews also sprayed insecticides over east Texas in the aftermath of Hurricane Harvey in 2017. C-130 crews have also flown both medical supplies and teams in response to natural disasters around the globe. With eleven versions of the aircraft produced, the C-130 is perhaps one of the most versatile aircraft ever made, with two models still in production. Its missions have spanned the globe for sixty-five years, making it truly a transport extraordinaire.