The Boeing C-17 Globemaster III and Lockheed C-130 Hercules are two of the largest military cargo aircraft in the world. There are some parallels in their design, capabilities, and use, but they vary in particular aspects. Below is a detailed comparison between the c17 vs c130.
History
C130
After World War II and the Korean War, it became clear to the United States Air Force (USAF) that piston-engine aircraft were not powerful enough. In February 1951, the U.S. Air Force issued new General Operating Requirements to the top aircraft manufacturing companies, including Lockheed, Boeing, Fairchild, Chase Aircraft, Martin, Northrop, North American, and Airlifts Inc.
They needed a tactical aircraft with a cargo compartment that would be 41feet long, 10 feet wide, and 9 feet high. It would accommodate 72 combat troops or 64 paratroopers or 92 passengers and have a combat transport aircraft design with a hinged loading ramp at the rear.
Lockheed, Boeing, Chase, Douglass, and Airlifts Inc. sent their proposals, while Fairchild, Martin, Northrop, and North American declined. The leading proposals were L-206 by Lockheed and a four-turboprop design by Douglas.
Lockheed won and proceeded to design the YC-130. Initially, it made two prototypes, and only one flew. After the prototype was confirmed, it delivered the first units to the U.S. Air Force in 1956 and manufactured 2,300 over the decades.
C17
In the 1970S, the U.S. Air Force (USAF) was actively looking for a more powerful tactical cargo aircraft. To find a suitable designer and manufacturer, it conducted the Advanced Medium STOL transport competition.
Boeing and McDonnell Douglas entered, proposing the YC-14 and YC-15, respectively. Both were great options that met and exceeded the USAF design requirements. However, they did not proceed to the development phase as USAF canceled the competition before announcing the winner.
The need for a powerful tactical aircraft continued to get dire. In 1980, the USAF reached out to McDonnel Douglas to design the C17, which partnered with Boeing.
The C17 design was inspired by several of its predecessors, including the Douglas C-74 Globemaster, Douglas C-124 Globemaster II, and the YC-15. It was mainly a redesign of the YC-15 with swept wings, a more powerful engine, and more space.
The design and development phase was quite expensive as the USAF incurred a loss of about $1.5 billion. The airlifter made its maiden flight on 15 September 1991, one year behind schedule due to limited funding as some key stakeholders felt that there could have been a more cost-effective alternative. Only 120 aircraft were produced and released in the market, rather than the 210 units initially proposed.
The C17 entered the USAF service on 17 January 1995. In 1996, the DOD ordered the production of an additional 80 units. In 1997, Boeing and McDonnell Douglas merged and continued to produce the C17. The most recent variant of the aircraft was released in November 2015.
Application
The C17 is primarily for strategic and tactical airlifting missions, such as transporting troops and cargo to war zones, and sometimes for medical evacuation and airdrops.
Aside from being used by the USAF, Australia, Canada, Qatar, United Kingdom, United Arab Emirates, Kuwait, and the Heavy Airlift Wing have also used it. This plane played a critical role during the Iraq and Afghanistan war and helped deliver humanitarian aid during the 2010 Haiti earthquake and 2011 Sindh floods.
The C130 is a medevac and cargo transport aircraft. However, it found wide application in other areas, including search and rescue, airborne assault, gunship, aerial fighting, aerial refueling, and weather reconnaissance. It is now mainly used as a tactical airlifter.
Like the C17, it was used worldwide, including in Argentina, Australia, Colombia, Canada, Belgium, Indonesia, the United Kingdom, Norway, and Saudi Arabia.
Size and Cargo Payload
The Boeing c17 is 174 feet long with a wingspan of about 169 feet. The cargo compartment is 88 feet long by 18 feet wide by 12 feet 4 inches high. For cargo operations, there is room for three crew members: a pilot, copilot, and loadmaster.
Its standard design includes rollers on the cargo floor for palletized cargo. However, the floor flips to provide a flat floor for loading vehicles and other rolling stock. It can accommodate three Stryker armored vehicles, one M1 Abrams tank, or two M2 Bradley armored vehicles.
It has a maximum payload of about 170,900 pounds with a maximum takeoff weight of 585,000 pounds. It can also carry troops as follows:
- 102 paratroopers or;
- 134 troops with sidewall and palletized seats or;
- 54 troops with sidewall seats or;
- 54 ambulatory patients and medical attendants
With a payload of about 170,900 pounds, it can cruise at an altitude of 28,000ft unrefueled for up to 2,400 nautical miles. Its average cruise speed is 450 knots (850km/h). When unloaded, it can cover a distance of up to 6,230 nautical miles.
It operates on short and narrow runways – 3500ft long and 90ft wide. The runways can be paved or unpaved, and thrust reversers make it possible to do a three-point turn on narrow taxiways. The aircraft has high-performance speed brakes that enable rapid deceleration and maneuvers. Each flight hour requires 20 manhours of maintenance.
Comparatively, the C130 has a higher crew capacity but lower load capacity overall. The cabin has room for up to five people, including two pilots, a flight engineer, loadmaster, and CSO/navigator. Its maximum payload is 42,000 lbs, and its troop capacity is as follows:
- 92 passengers or;
- 64 airborn troops or;
- 74 litter patients with 5 medical crew or;
- 6 pallets
It can fit two to three humvees, two M113 armored personnel carriers, or a CEASER self-propelled howitzer.
Engine
The C17 is powered by four Pratt & Whitney F117-PW-100 turbofan engines based on the Pratt & Whitney PW2040 used in the commercial aircraft Boeing 757. Each of the four engines is rated to produce 180kN thrust.
The engine thrust reversers direct exhaust air forward and upwards, reducing the risk of foreign objects such as runway debris from getting in. The reverse thrusters provide adequate torque to back up the aircraft while taxiing, and the torque also provides adequate drag in maximum rate descents. Vortex surfing tests indicate that the C17s have up to 10% fuel saving.
On the other hand, the initial model of the C130 was powered by four Allison T56-A-11 or nine engines. It has since been upgraded and is now powered by the Allison T56-A-7 turboprop engines. The engines continue to upgrade over the years with the development of new versions of the C130.
One of the most powerful engines on a C130 was the Allison T56-A-15, which was fitted on the C-130E. It improved the performance of the aircraft significantly.
The latest model, the C130J is outfitted with the Rolls-Royce AE2100D3 turboprop engine coupled with a six-blade composite propeller. This engine design has delivered unprecedented performance compared to previous models.
Specifications Summary and Comparison
| C17 | C30 | |
| Crew | 3 | 5 |
| Capacity | 170,900lb | 42,000lb |
| Length | 174 feet | 97ft |
| Wingspan | 169 feet | 132ft |
| Height | 55 feet | 38ft |
| Wing Area | 3800 sq.ft | 1,745 sq.ft |
| Empty Weight | 282,500lb | 75,800lb |
| Maximum Takeoff Weight | 585,000lb | 155,000lb |
| Fuel Capacity | 35,546 gallon | 8,455 gallons |
| Cruise Speed | 450kN/520mph/830km/h | 292kN/336mph/541km/h |
| Service Ceiling | 45,000ft | 33,000ft |
| Landing Distance | 3,500ft | 1400ft |
Variants
Different models of the C17 and C130 have been developed over the years. The C17 has had fewer model variations than the C130.
C17 variants include:
- C17A. The initial version of the C17.
- C17A – ER. An upgrade of the 17A was incorporated in 2001. It had an additional center wing tank providing an extended range.
- C17B. A tactical airlifter version of the C17A with double-slotted flaps, additional main landing gear, more powerful engines, and systems for shorter take-off and landing distances. Boeing provided the U.S military with the C17B in 2007 as an aircraft for carrying Future Combat Systems and other equipment.
- MD-17. Proposed variation for civilian operation. It was later renamed the BC-17.
There are more than 40 variants of the C130 on the market, including civilian aircraft. While some had minor upgrades of the previous models, others were a total overhaul of certain parts. Below is a brief overview of the most common C130 aircraft.
- C-130A. The earliest model of the tactical airlifter.
- C-130B/E/F/G/H/K/T. Progressive upgrade of the C130A.
- C-130A-II. Incorporated the early version of the Electronic Intelligence/Signals Intelligence aircraft’s system.
- C-130J. Had newer engines, updated systems, and avionics.
- C-130B BLC. An upgrade of the C-130B that was fitted with a double Allison YT56 gas generator pod.
- C-130K. Designated C-13OJ for the Royal Air Force service.
- AC-130A/E/H/J/U/W. Gun shipping variants.
- C-130D/D-6. A ski-equipped version of the C130 for use specifically in snow and ice operations by the Air National Guard Department of the U.S Air Force.
- C-130E/H/J Hercules. Particularly designed for the Canadian Armed Forces.
- C-130M. An upgrade of the C-130H was specifically produced for the Brazilian Air Force.
- DC -130A/E/H. Used for drone control by the USAF.
- EC-130E/J/H/V. Used by the Air National Guard for psychological operations such as procedural air-to-ground attack control and airborne control and attacks.
- HC-130 B/E/H/P/N/J. Specific variants were used for different operations such as combat search and rescue, aerial refueling, and airlift.
- JC-130. Used for spying and drone recovery.
- KC 130F/R/T/J. Aerial refueling.
- TC-130. Aircrew training.
- VC-130H. Vip transport.
- WC-130A/B/E/H/J. Weather reconnaissance.
Accidents
Generally, the C130 has had low accident incidents. According to a Royal Air Force investigation, the C130 recorded an accident rate of one aircraft per 250,000 flying hours over 40 hours.
On the other hand, the C17 has had more incidents of accidents. The first notable incident happened in September 1998 when one of the C17s suffered a landing gear failure when landing in Iceland. Although there were no significant injuries or fatalities, the landing gear sustained major damage.
In January 2009, a C17 made a gear landing at the Bagram Air Base. Upon investigation by the USAF Aircraft Accident Investigation Board, it was established that the landing error was a result of the crew’s failure to adhere to the landing protocol.
In July 2010, another C17 crashed at the Elmendorf Airforce Base in Alaska while practicing for the Arctic Thunder Air show. It killed all the four crew members that were on board. Post-crash investigations revealed that the aircraft had crashed due to a pilot error.
Two more pilot error incidents were reported in 2012. The first happened in January 2012 in the Forward Operating Base Shank in Afghanistan. The pilot had miscalculated the stopping distance and crashed into some structures. There were no injuries or fatalities. The other happened in July 2021 when the pilot mistakenly landed at the Peter O. Knight Airport instead of the MacDill Airforce Base.
The most recent accident happened in April 2021 when a C17 caught fire in the undercarriage at the Charleston Air Force Base. Although the fire had begun spreading to the fuselage, it was extinguished in time without any injuries or fatalities.
Conclusion
Both the C17 and C130 are military transport aircraft. They were designed on request by the United States Air Force to meet the need for powerful strategic and tactical aircraft. The C17 has been around for longer and has numerous variants. The C17 is a newer type of tactical cargo aircraft with fewer variants.
The C17 is much bigger in terms of cargo space and size. It also offers superior performance with a higher cruise speed than the C130. Both land and take off across a short distance on both paved and unpaved runways.
The models are still operational in different parts of the world and continue to be upgraded to incorporate advancing technological features. Although more C17 accidents have been reported, they were mostly a result of pilot error.
