Is This the Largest Plane Ever? 5 Surprising Facts About the C-5M Super Galaxy

Is This the Largest Plane Ever 5 Surprising Facts About the C-5M Super Galaxy

The Lockheed Martin C-5 Galaxy family of aircraft includes the original “A” model, the “B” model, the “C” model, and the “M” model. Lockheed Martin produced 81 “A” models and 50 “B” models, and all 120+ aircraft in the fleet have since been upgraded to the C-5M Super Galaxy configuration.

As of now, 52 C-5Ms remain in active service, while the rest of the fleet is in long-term storage at the 309th Aircraft Maintenance and Regeneration Group (also known as the “Boneyard”) at Davis-Monthan AFB in Tucson, Arizona. The C-5M is stationed across five bases in the United States:

  • Westover Air Reserve Base, MA
  • Travis AFB, CA
  • Dover AFB, DE
  • Joint Base San Antonio-Lackland, TX
  • Robins AFB, GA

Early Strategic Airlifters and the Development of the C-5

In the late 1950s, the U.S. Air Force relied on two strategic airlifters: the Douglas C-124 Globemaster II (introduced in 1949) and the larger Douglas C-133 Cargomaster (introduced in 1956). While both were reliable and had large payloads for their time, they had a major limitation: slow cruising speeds. The C-124 flew at 200 knots, and the C-133 at 312 knots. In contrast, the Lockheed C-141 Starlifter, which replaced them, cruised at 495 knots.

To address this, the Air Force acquired 60 C-135 Stratolifters, which were designed as cargo-only aircraft. Although their cruising speed was similar to the C-141, their payload capacity was lower, and they could not carry oversized cargo. This limitation was overcome by the C-141, which could carry large items like a fully assembled Minuteman ICBM. However, some oversized items still couldn’t fit, leading to the use of the Douglas C-133, which had a much larger cargo bay.

The introduction of the C-5A in 1969, capable of carrying even larger loads, effectively replaced both the C-124 and C-133 within two years.

The C-5M Super Galaxy: The Largest U.S.-Built Aircraft

The C-5M remains the largest American-built aircraft ever to enter service, both military and civilian, and it continues to serve after 55 years. Following the introduction of the C-141 Stratolifter in 1963, the Air Force was satisfied with its performance but still needed a larger aircraft for oversized cargo. The C-5 program was initiated in response to this need.

In 1962, the Air Force issued a Request for Proposal (RFP) for a replacement, which led to the development of the C-5. Lockheed won the contract in 1965, and the C-5A entered service in 1969. The C-5’s vast cargo capacity and ability to transport oversized loads made it a key component of the Air Force’s strategic airlift capability.

C-5M Conversion and Upgrades

The conversion of older C-5 models to the C-5M configuration involved several critical upgrades:

  1. New Engines: The C-5M is powered by the G.E. F138 turbofan engine, a significant improvement over the original TF39 engines, providing better fuel efficiency and thrust.
  2. Wing Reinforcement: During maintenance, non-destructive testing (NDT) revealed cracks in the wing roots of C-5A models. After engineers redesigned the wings, the new C-5B production model incorporated these changes.
  3. Avionics Overhaul: The most significant change in the C-5M is the complete overhaul of its avionics, including a glass cockpit, a new autopilot system, and modernized navigation equipment.
  4. Extended Service Life: Through a reinspection, the Air Mobility Command (AMC) confirmed that with the new wings and upgrades, the C-5’s service life could be extended to 30,000 flight hours, ensuring its continued utility for years to come.

The Evolution of the C-5’s Engine

The C-5’s development faced significant challenges, particularly with its engines. Initially, six engines were required to meet the aircraft’s size, speed, and payload requirements due to the underpowered and inefficient engines of the time. This led to the use of six traditional jet engines, which were not fuel-efficient.

In response, the Air Force issued an RFP for a new, more efficient engine, ultimately choosing General Electric’s TF39 turbofan engine. This engine, which featured a high-bypass ratio, significantly improved the C-5’s fuel efficiency and thrust, enabling longer flight ranges without the need for mid-air refueling.

In 2006, the Air Force began re-engineering the C-5 fleet with the F138-GE-100 engines, which provided even better performance, delivering 22% more thrust, a 30% shorter takeoff run, a 38% higher climb rate, and longer range capabilities.

C-5 Features and Capabilities

The C-5 is known for its massive cargo compartment, which is capable of carrying:

  • Up to five UH-60 Blackhawk or AH-64 Apache helicopters
  • 36 standard USAF 461L air cargo pallets
  • 81 soldiers with their gear for deployment
  • A wide range of combat equipment
  • Six MRAP (Mine Resistant Ambush Protected) vehicles

In a notable demonstration in 1974, a C-5A successfully air-dropped an 86,000-pound Minuteman ICBM over the Pacific Ocean, proving its ability to launch an ICBM from the air.

The C-5’s cargo bay is so large it could fit an eight-lane bowling alley, and by 1973, all 81 C-5As on order had been delivered. The production line was restarted in 1982 after President Reagan approved it, leading to the creation of 50 updated C-5Bs.

Current C-5M Squadrons and Future Prospects

At its peak in the early 2000s, there were 15 C-5 squadrons across active duty, the Air Force Reserve Command, and the Air National Guard. By 2007, most of the fleet had been upgraded to the “M” configuration. Today, the fleet is reduced to 52 aircraft across nine squadrons, including both active duty and reserve units:

  • Travis AFB squadrons: 22nd Airlift Squadron (active duty), 312th Airlift Squadron (reserve)
  • Dover AFB squadrons: 9th Airlift Squadron (active duty), 709th Airlift Squadron (reserve)

Additional reserve squadrons include the 773rd Airlift Training Squadron and the 339th Flight Test Squadron, which provide training and test support for the C-5M fleet.

The C-5Ms still in long-term storage will be invaluable to the U.S. military should a future conflict arise, as they can be quickly reactivated to support large-scale airlift operations.

Source