Lockheed C-5 Galaxy
Global Airlift: Anything, Anytime, Anywhere
The Lockheed C-5 Galaxy is a heavy logistics military transport aircraft
designed to provide world-wide massive strategic airlift. The CONUS-based
fleet can provide delivery of palletized, oversized and outsized cargo, as
well as passengers or combat-ready troops, anywhere in the world on short
notice. The aircraft can takeoff and land in relatively short distances
and taxi on substandard surfaces during emergency operations. The C-5 also
plays a limited role in the airdrop and special operations arenas.
In 1963, realizing that they needed a jet-powered replacement for the
exhausted, turboprop-powered C-133 Cargomaster, the United States Air
Force began to study very large logistic transports. After reviewing
several airframe designs, they eventually choose one similar to that of
the C-141A Starlifter featuring a high-set wing (swept 25 degrees), four
underwing jet engines and a T-tail.
This enormous aircraft, first known as the CX-HLS (Cargo
Experimental-Heavy Logistics System) transport, was required to carry a
payload of 125,000 pounds (56,700kg) over a distance of 8,000 miles
(12,875km), or twice that load over a shorter distance. It also had to be
able to operate, at maximum weight capacity, from the same runway lengths
and semi-prepared runways as the C-141A (8,000 feet (2,438m) takeoff /
4,000 feet (1,219m) landing). Another major requirement, and the most
controversial, was the design-life factor for the wing; it must survive
for 30,000 flying hours.
The design competition was between Boeing (which entered its initial
designs for the Model 747, before it was incorporated as a commercial
passenger carrier), Douglas and Lockheed-Georgia. Lockheed won the
contract in October 1965 with a design that was an extension of the
company's Hercules/Starlifter series. With a gross weight of 764,500
pounds (346,771kg), Lockheed's Model 500, later designated C-5A Galaxy,
dwarfed not only other Air Force transports but also every other type of
aircraft in existence.
Construction of the prototype began in August 1966. The first C-5A Galaxy
(#66-8303) was "rolled out" on 2 March 1968 and prepared for initial
flight trials at Lockheed's Marietta plant, located adjacent to Dobbins
AFB in Georgia. The maiden flight took place on 30 June 1968 and lasted 94
minutes; Lockheed pilots Leo J. Sullivan and Walter E. Hensleigh were at
the controls. (Note: This aircraft was lost following a ground fire on 17
The first phase of manufacturer's flight trials proceeded without major
problems (except for the loss of a main wheel during a routine landing;
the media had a field day with this event). In July 1969, full-scale
structural ground static tests resulted in a premature wing failure at 84
percent of the scheduled maximum design load. Nevertheless, while
corrective measures were devised, flight tests proceeded in Georgia and
California, where the 2nd C-5A had been delivered to Edwards AFB on 4 June
1969 to take part in the 6-month joint Air Force/contractor Category I
Commonly described as, "The Box That The C-141 Came In," the C-5A Galaxy
was presented to the United States Air Force, for training purposes, in
December 1969. The first operational aircraft were delivered to the 437th
Military Airlift Wing (MAW), Charleston AFB, SC, in June 1970.
In the mid-1970s, wing cracks were found throughout the fleet.
Consequently, all C-5A aircraft were restricted to a maximum of 50,000
pounds (22,680kg) of cargo each. To increase their lifting capability and
service life, 77 C-5As underwent a re-winging program from 1981 to 1987.
(In the redesigned wing, a new aluminium alloy was used that didn't exist
ten years prior.) The final re-winged C-5A was delivered in July 1986.
In 1982, a new production version, the C-5B, was authorized in which all
modifications and improvements evolved in the C-5A program were to be
incorporated, including upgraded TF-39-GE-1C turbofan engines,
extended-life wings, Bendix colour weather radar, triple Delco inertial
navigation systems (INS), an improved automated flight control system (AFCS)
and a new, more advanced Malfunction Detection Analysis and Recording
System (MADAR II). The C-5B dispensed with the C-5A's complex crosswind
landing gear system.
The first flight of the C-5B (#83-1285) took place on 10 September 1985.
Delivery of the 50 new aircraft commenced in January 1986 and ended in
April 1989. All C-5Bs are scheduled to remain in the active duty force,
shared by comparably sized Air Force Reserve associate units.
In the late-1980s, NASA had two C-5As (#68-0213 & #68-0216) modified to
accommodate complete satellite and space station components. In each
aircraft, the troop compartment, located in the aft upper deck, was
removed and the aft cargo-door complex was modified to increase the
dimensions of the cargo compartment's aft loading area. Both aircraft are
currently assigned to Travis AFB in Fairfield, California and have been
redesignated as C-models. (Some unofficial sources claim this modification
also enables the C-5C to be used for covert transportation of classified
material between Lockheed's Skunk Works in California and the test centre
at Groom Lake, Nevada, also known as Area 51. Lockheed and the U.S.
government will neither confirm nor deny the authenticity of this
Until the introduction of the Russian An-124 "Condor" (1982), the C-5A
Galaxy was the largest and heaviest aircraft in the world. With its
massive payload capacity, it has the capability to carry fully-equipped,
combat-ready troops to any area of the world on short notice and provide
the field support necessary to maintain a fighting force. Since 1970, it
has opened unprecedented dimensions of strategic airlift in support of
national defence and is invaluable to the Air Force mission and world-wide
humanitarian relief efforts.
Exterior Setup - Four turbofan jet engines, high-set wing (swept 25
degrees), T-tail, forward and rear cargo loading assemblies, and a
visor-type upward-hinged nose.
Upper-Deck Accommodations - The forward upper deck (flight deck) seats a
cockpit crew of six, a relief crew of seven, and eight dignitaries or
couriers; it also has two bunk rooms with three beds in each. The rear
upper deck (troop compartment) seats 73 passengers and two loadmasters.
Both upper deck compartments are fully pressurized, air-conditioned and
incorporate galleys for food preparation and lavatories.
Cargo Compartment - Capacity: 36 fully-loaded 463L-type cargo pallets (88"
x 108" @ 10,000 pound (4,536kg) capacity); 270 passengers in the air-bus
configuration*; six transcontinental buses; two M1-A1 Abrams main battle
tanks; seven UH-1 Huey helicopters; one U.S. Army 74-ton mobile scissors
bridge. (A combination of pallets and wheeled vehicles can be carried
together when required.)
The Galaxy's massive cargo compartment, with its upward-hinged visor in
the nose and outward-opening "clamshell" doors in the rear, accommodates
drive-through loading/unloading of wheeled or tracked vehicles using
full-width ramps at each end. To accommodate faster, easier loading of
outsized or unpowered equipment, each ramp contains an internally-housed
For rapid handling of palletized equipment, the forward and rear ramp
assemblies can be repositioned to truckbed height, approximately 10 feet
(3.0m) above the ground, and the entire cargo floor converted into a
rollerized conveyor system. Thirty-six standard 463L cargo pallets can be
loaded aboard in about 90 minutes. When palletized cargo is not being
carried, the roller conveyors can be turned over to leave a smooth, flat
surface to accommodate wheeled or tracked vehicles.
The C-5 Galaxy has a 121 foot long cargo floor (one foot longer than the
Wright Brothers first flight at Kitty Hawk, North Carolina) and nearly
35,000 cubic feet of available cargo space — five times greater than that
of the C-141A Starlifter! The entire cargo compartment is pressurized and
* The C-5 only carries passengers or troops in the lower-deck cargo
compartment during emergency operations or on special missions authorized
by Headquarters AMC.
Landing Gear - The enormous C-5 Galaxy has a very unique landing gear
system consisting of a single nose strut, four main bogeys and a total of
28 wheels. The complex system offers "high flotation" capability for
unpaved surfaces, freewheel castoring to facilitate ground manoeuvring,
and an offset swivelling capability (20 degrees left or right) for
crosswind landings**. The landing gear system also has the capability of
raising each set of wheels individually for simplified tire changes or
brake maintenance. Size aside, the aircraft can takeoff or land just about
anywhere in the world.
To provide maximum logistical flexibility, the C-5's landing gear assembly
also has a three-position "kneeling" system, which can be utilized to
lower the aircraft's cargo floor to truckbed height. "Kneeling" of the
aircraft is especially needed when loading outsized or long wheel-based
equipment because it reduces the angle of the forward or aft ramp critical
** Not adapted to the second production B-model aircraft, and has since
been removed from all A-models.
Power Sources - The electrical system has four engine-driven generators,
each powerful enough to supply the aircraft with sufficient electricity.
Each of the two main landing gear pods carries an auxiliary power unit (APU)
and air turbine motor (ATM) to supply electric/pneumatic and hydraulic
power, respectively, for engine starts, ground air conditioning and
heating, main landing gear kneeling operations, and forward/aft cargo door
Engines - Four General Electric TF39-GE-1C turbofan engines, rated at
41,000 pounds (183kN) of thrust each, mounted on pylons under the wings
power the C-5 Galaxy. Each engine pod is nearly 27 feet (8.2m) long,
weighs 7,900 pounds (3,583kg) and has an air intake diameter of more than
8.5 feet (2.6m).
During engine development, a Boeing B-52E (#57-0119) was modified for use
as an engine testbed. The engine was mounted on the right inboard pylon in
place of the two J57s normally installed there. The single TF-39 turbofan
had nearly as much thrust as four standard J57 turbojets.
Fuel Capacity - The C-5 Galaxy has 12 integral wing tanks with a capacity
of 51,450 gallons (332,500 pounds) of fuel — enough to fill more than six
standard railroad tankers!
Inflight Refuelling Capability - The C-5A Galaxy was the first transport
aircraft to incorporate inflight refuelling capability as an original
design feature. The ability to aerial refuel allows the aircraft to stay
airborne indefinitely. With aerial refuelling, crew endurance is the only
limit to the aircraft's range. (Relief crews are carried on long flights
to minimize the crew fatigue factor.)
MADAR - An automatic trouble-shooting system constantly monitors more than
800 test points in the various subsystems of the aircraft. The Malfunction
Detection Analysis and Recording System (MADAR) uses a digital computer to
identify malfunctions in replaceable units. Failure and trend information
is recorded on magnetic tape for analysis.
Avionics - The C-5 Galaxy has sophisticated communications equipment and a
triple inertial navigation system (INS), making it nearly self-sufficient.
It can operate without using ground-based navigational aids.
Countermeasures - Under the Pacer Snow project, two C-5s received
installation of ALE-40 flare dispensers and an AAR-47 missile warning
system to provide a measure of self-defence.
The C-5 Galaxy is specifically designed to transport all types of military
fighting equipment and associated personnel. The entire spectrum of
military inventory, anything and everything that the Army ever intended to
be airlifted — rolling and tracked armoured equipment (including main
battle tanks), bridge launchers, helicopters, bulk cargo, troops, etc. —
can be transported swiftly and efficiently aboard the C-5. inflight
refuelling capability gives the aircraft nearly unlimited range and
increases its flexibility for troop and cargo delivery.
In the airdrop arena, the C-5 Galaxy is capable of delivering up to 60,000
pounds (27,216kg) of equipment per drop. Standard airdrop operations
include the following types of hardware: Hummers, Bradleys, tanks, road
graters and Howitzers. The C-5's aerial-delivery system is compatible with
airdrop platforms of 8, 12, 16, 20, 24, 28 and 32 feet in length. Most
personnel drops consist of 73 combat-ready troops.
In 1984, a re-winged C-5A flew at a then world record gross weight of
920,836 pounds (417,684kg) after being air refueled. Less than five years
later, a C-5B set a new airdrop record of 190,493 (86,406kg) pounds. The
drop, consisting of four 42,000 pound (19,051kg) Sheridan tanks and 73
combat-ready troops, occurred over Fort Bragg, North Carolina on 7 June
1989. The C-5 Galaxy also holds the "unofficial" world record for the
heaviest drop over a single zone ... two 60,000 pound (27,216kg)
The most dramatic display of the Galaxy's capability and value was during
operations Desert Shield and Desert Storm. Galaxies comprised only 12
percent of the combined airlift fleet, yet they carried 44 percent of all
airlift cargo and flew 23 percent of all strategic airlift missions.
Ninety percent of Air Force C-5s were used in Desert Shield/Storm, the
rest were flying high-priority missions elsewhere around the world.
Overall, the strategic airlift to the Persian Gulf was the largest since
World War II. By the cease-fire, Air Force airlifters had moved 482,000
passengers and 513,000 tons of cargo. Viewed in ton miles, the airlift of
Operation Desert Shield/Storm was equivalent to repeating the Berlin
Airlift, a 56-week operation, every six weeks.
Since 1968, only two C-5s have crashed; both were assigned to the 60th
Military Airlift Wing (MAW) at Travis AFB, California. The first loss
(#68-218) occurred during Operation Babylift on 4 April 1975 near Saigon,
South Vietnam. The second loss (#68-228), crewed by members of the 433rd
MAW at Kelly AFB, Texas, occurred during Operation Desert Shield on 29
August 1990 at Ramstein AB, Germany.
The Future: Modernization
The U.S. Air Force took delivery of the first C-5A in 1969. The fleet was
later retrofitted with a new wing in the mid-1980s. With a projected
structural service life of over 50,000 hours, structurally, the C-5 could
last well into the 21st century, depending on the model and other factors.
However, system obsolescence, reliability and maintainability, operating
costs, impacts of corrosion, and required repairs all factor in the
service life of an aircraft. Currently, the C-5 has the highest operating
cost of any Air Force weapon system.
While the C-5 Galaxy has been the backbone of America's strategic airlift
fleet since the early-1970s, reliability rates are dropping because the
engines and avionics are showing their age. However, testing and analysis
reveal that the C-5 has 80 percent of its structural service life
remaining. With modernization, "C-5 operators can realize a 34 percent
less cost-per-flying-hour and 44 percent less cost-per-ton-mile of cargo —
all at 20 percent of the cost of comparable new aircraft."
Lockheed Martin has submitted a proposal to the C-5 Galaxy Modernization
Program to replace existing avionics with a modern, highly-reliable
digitalized system on all 126 C-5s in the U.S. Air Force fleet. Partnered
with LMAS, Honeywell Defence Avionics Systems is providing a Versatile
Integrated Avionics package, an FAA-certified system developed by its
commercial sister divisions that is the latest implementation of
Honeywell's integrated modular avionics technology.
Modernization of the Galaxy's propulsion system would be a follow-on
program to the avionics modernization. While the U.S. government has not
authorized funds for a new C-5 powerplant until 2003, the program could be
moved up after an Analysis of Alternatives has been completed.
Lockheed Martin is teaming with GE Aircraft Engines to offer a new
propulsion system anchored by the popular General Electric CF6-80C2
engine. Backed by more than 40 million hours in service, the CF6-80C2
engine can assure operators "like new" aircraft reliability and
dramatically improved performance.
With the CF6 engines, the C-5's initial cruise ceiling will increase from
24,000 feet to 33,000 feet. Also, the new engines will provide the Galaxy
with 22 percent greater takeoff thrust, 30 percent less takeoff roll, and
58 percent less time-to-climb than with the C-5's current TF39 engines
while operating at a 17 percent derate.
490 kt / 564
5,526 km /
span 67.88 m /
222 ft 8.5 in
length 75.54 m / 247 ft 10 in
height 19.85 m / 65 ft 1.5 in
kg / 374,000 lb
max. take-off 379,657 kg / 837,000 lb
four 19504-kg (43,000-lb) dry thrust General Electric TF39-GE 1C