(C-5A image). The USAF launched the requirement known as “Heavy Logistics System” (CX-HLS), in view of the need for an aircraft that could carry outsized loads such as missile systems thousands of kilometers in direct flight. Although the USAF had huge fleet of C-130 Hercules, C-133 Cargomaster and C-141 Starlifter in the early 1960s, all of these models had limitations regarding the dimensions and capacity of their cargo bays. It is true that the C-133‘s cargo bay was the largest, but its piston engines limited its speed and were poorly suited for strategic transport.(C-5A image). The CX-HLS program requirements specified that the new model had to carry 4 jet powered engines that would allow the aircraft to reach 800 km/h cruising speed. The maximum payload should reach 81.6 tons and the cargo bay should be 30.5 meters long, 5.24 meters wide and 4.11 meters high with front and rear access doors. The initial order would be 58 aircraft with the option of subsequent contracts for a total number of 115 units.(C-5A image). In the spring of 1965 the 3 main manufacturers of military transport aircraft, Boeing, Douglas and Lockheed, presented their projects to the USAF, which in 5 months considered Lockheed the winner of the contest. Apparently the USAF preferred the Boeing design, which turned out to be the embryo of the successful B-747 Jumbo Jet airliner, but the cost of the Lockheed aircraft was lower and tipped the balance in its favor. At the same time, a competition had also been opened to equip the new aircraft with new engines, with Pratt & Whitney and General Electric as competitors, resulting the latter as the winner.(C-5A image). After its victory, Lockheed began to propose different variants for the new aircraft with what it expected sales of several hundred units. Paradoxically, the total orders have been only 131 units, while the “loser”, the Boeing 747 Jumbo Jet model, has been one of the greatest successes in commercial aviation with 1,558 units sold to airlines and users around the world. Sometimes, the “last” will be the first …., and not only in the Kingdom of Heaven.(C-5A image). Lockheed started with design and manufacturing, having to abide by very severe weight restrictions. At the end of 1966, a team of engineers was created for this purpose, which was in charge of analyzing any new component that would add a weight of more than 125 grams. Despite all efforts, the aircraft that made the maiden flight, in the summer of 1968, weighed 1,000 kg more than the maximum required weight. The weight of the external paint of the gigantic C-5 is around 1 ton, so if the aircraft had flown without it, the objective would have been met, as observed from Lockheed.(C-5A image). On March 2, 1968 the first C-5 Galaxy left the manufacturing plant in Marietta, Georgia, but it was not until June 30 that it made its maiden flight. The huge aircraft soon became embroiled in controversy due to technical problems and rising costs, prompting a Congressional investigation during 1968 and 1969. However, the trial period continued despite everything, even after give the C-5 the dubious honor of being the first development program to go over budget by 1 billion dollars (1,000 millions).(C-5A image). At this time the C-5 Galaxy was the largest aircraft in the world, and unfortunately, also the most expensive, with a unit price of 60 million dollars. This price was 50% higher than estimated of around 40 million/unit, causing initial estimates of 115 aircraft to be drastically reduced to only 81 units. So dire was the economic situation for Lockheed that in 1971 the U.S. Government granted several loans to the company to avoid bankruptcy.(C-5A image). The huge weight of the aircraft was a constant problem and in July 1970 it was decided to lower the payload capacity from 100 to 86 tons due to wing problems. In addition, a serious fatigue problem arose in the airframes, calculating that only 10% of the C-5 fleet would meet the expectation of 19,000 flight hours without cracking the wings. To add insult to injury, in October 1970 a C-5 suffered a fire, killing a Lockheed worker and in September 1971, another C-5 suffered a gruesome breakdown. While it was taxiing, it suffered the fall to ground of a running engine, which rose several tens of meters and fell on the runway. This incident meant that all C-5s were grounded for a time.(C-5A image). In 1976 a new program began so that from 1980 onwards new wings could be installed throughout the fleet so that they could operate at full load capacity again. In 1980, due to serious fatigue problems detected during the continuous tests, it was decided to lower the payload in peacetime operations to 23 tons!. Finally, the change of the wings took place between 1980 and 1987 at a cost of about 1,500 million dollars.(C-5A image). Unfortunately for the Galaxy, its contact with the ground crews earned it a lot of unloving nicknames due to the amount of mechanical and maintenance problems. The best known were the “Big MAC”, “White Elephant” or “Fat Albert”, and the worst of all, “F.R.E.D.”, which was the acronym for “Fantastic (or Fucking) Ridiculous Economic/Environmental Disaster”.(C-5A image). On April 4, 1975 there was the most catastrophic accident of the Galaxy‘s career. During Operation Babylift, which consisted of the evacuation of children and orphans from Saigon, the rear loading ramp broke loose, damaging the rear of the fuselage and the tail hydraulics, leaving the aircraft almost unmanageable. During the emergency landing, 144 people died, including 78 children. Fortunately, there have been no more accidents as tragic as this one, but there are at least eight other incidents to count. Considering the number of units and its busy career, this aircraft cannot be said to be a “widowmaker”, but once it has gained fame, it is very difficult to get rid of.(C-5A image). The C-5 Galaxy has a continuous cargo bay that extends over the entire length of the aircraft with the cockpit located above it. The aircraft has cargo doors in the front and the rear, so loading and unloading can be done simultaneously. At the rear there are two large doors that open outwards while the entire front part (the nose) opens upwards, allowing the entry of huge loads. The cargo deck has dimensions of 37 meters long, 5.80 wide and 4.10 meters high.(C-5A image). Above the cargo bay, an upper floor was installed that can accommodate up to 80 passengers and the crew in charge of loading and unloading tasks. The floor of the cargo deck has a built-in roller system that facilitates the movement of standardized USAF pallets. Inside the cargo bay, up to thirty-six 463L Master Pallets can be placed. At each end of the cargo deck there are full width ramps that allows quick loading and unloading tasks.(C-5A image). Despite the problems, the cargo capacity of the C-5 Galaxy is really impressive, being able to carry 2 Abrams MBTs, or 4 Sheridan light tanks, or 5 Bradley IFVs, or 10 LAV-25 APCs, or Chinook helicopter, or 6 AH-64 Apache attack helicopters or seating can be installed for a total of 363 passengers. The Galaxy rests its weight of almost 400 tons on a main landing gear made up of 28 wheels. This system can be lowered hydraulically so that the floor of the cargo deck is lower and thus facilitate loading and unloading.(C-5B image). In 1982, Congress approved funds to build a new version of the C-5 Galaxy designated as C-5B. Fifty new aircraft are ordered and delivered from January 1986 to April 1989. The acquisition of this aircraft began to be considered in 1980 after a study by Congress in which it was requested that USAF be capable of transporting 66 million ton-miles per day. At the time, USAF transportation capacity was around two-thirds of that figure.(C-5B image). It is said that the construction of this second batch of C-5s was possible, several years after the first one was delivered because Lockheed did not destroy the tooling for its construction. According to the contracts, each time a series of aircraft is finished, the USAF orders the destruction of all tooling, but in this case it is unknown if that was requested or if Lockheed did not obey the order. According to the legend that runs by Lockheed, when the USAF gave the order of destruction, an executive of the company ignored and the tooling was stored and kept out of sight.(C-5B image). Lockheed after learning about the congressional study approached the USAF and offered them an additional batch of C-5s for a fixed price. It was decided that the new aircraft would be virtually the same as the modernized C-5A but with added enhancements, such as a new flight data recording system (AFCS), a solid state MADAR II malfunction analysis system, and a simplified landing gear. Finally, a new batch of fifty C-5B was contracted at a price of 120 million dollars per unit. On this occasion there were no protests as the price of each of these aircraft was half of the projected C-17 Globemaster III.(C-5B image). It is certain that the cost savings of the new C-5B had a lot to do with the tooling issue stored at Lockheed and that it appeared to have an estimated price of about 1,000 million dollars. The new aircraft was a success from the start and set several world records, such as the launch on June 7, 1989 of 73 paratroopers and 4 Sheridan light tanks totaling 86,313 kg, the largest load dropped in flight by an aircraft.(C-5B image). The new C-5Bs left the factory with the new wings designed for the entire C-5A fleet, which was to allow them a 30,000-hour lifetime. They also received the new Bendix AN/APS-133 color weather radar. Subsequently, all C-5Bs received IR and electronic countermeasures kits within the Pace Snow program of the early 1990s. These kits consisted of several AN/ALE-40 flare dispensers and an AN/AAR-47 missile warning system. Despite a fresh offer of more additional aircrafts from Lockheed, the USAF declined, considering the current fleet of C-5s sufficient.(C-5C image). In the early 1990s, two C-5As were converted to the “Space Container Modification” configuration to carry out large container transports for NASA. The upper compartment for troops was eliminated, the rear part of the cargo bay was modified and the two rear cargo doors were replaced by others with “accordion type” opening. These two aircraft were designated as C-5C, although the manuals contain the reference “C-5A (SCM)“. These two aircraft were converted in 2017 to the C-5M variant, the only one currently in service.(C-5B image). At the end of the 90s, the avionics of the C-5A/B began to become obsolete and the GE TF-39 engines were also considered old compared to the current ones. To solve these problems, two programs called “Avionics Modernization Program (AMP)” and “Reliability Enhancement and Re-engining Program (RERP)” were started. The AMP program will be applied over all existing C-5 fleet, but the RERP program will be only fitted in C-5B aircrafts. With these improvements, it was hoped to improve the availability of the aircraft to a minimum of 75%. It is also calculated in a saving of about 20,000 million dollars until 2040.(C-5M image). The AMP program started in 1998 and consisted of the installation of a traffic collision avoidance system (TCAS), a new autopilot, a ring laser navigation system with GPS receiver, a full authority digital engine controls (FADEC) and the replacement of all the analog elements of the instrument panel with a flatscreen “glass” cockpit. In addition, all communications and avionics have been modernized. All these improvements allow the Galaxy to operate within the Air Force Global Air Traffic System. The first modified aircraft flew in 2002.(C-5M image). The RERP program consisted of the replacement of the original GE TF-39C engines with new GE F138-GE-100 and new improvements in the landing gear, pressurization systems and certain parts of the airframe. The new engines are 20% more powerful allowing the Galaxy to shorten takeoff run by 30% and improve the initial climb rate by almost 40%. These improvements allow even greater load capacity and improve its range due to the lower consumption of the new engines. The first C-5B modified through the RERP program flew in June 2006 under new designation C-5M “Super Galaxy“. The first Super Galaxy was delivered to the USAF in December 2008 and the last of the 52 upgraded aircraft was delivered in August 2018.(C-5A image). The first operational aircraft designated as C-5A Galaxy was delivered in June 1970 to the 437th Airlift Wing based in Charleston AFB, South Carolina. Deliveries continued until 1973, when the expected 81 units were reached. The first flight to Vietnam took place in August 1970, and the fear that the huge Galaxy was a clear target for the Viet Cong, caused the aircraft to be unloaded and was back in the air in less than an hour from its arrival.(C-5A image). As the Vietnam War progressed towards its end, the work of the C-5A Galaxy intensified and the weight restrictions were relaxed. The C-5 proved that it was capable of carrying almost anything, tanks, helicopters, construction machinery and even six partially disassembled F-5 fighter-bombers at a time. This aircraft was capable of unloading up to 60 tons of material in less than 20 minutes, something never seen before.
