When Lockheed engineers began work on the massive C-5A Galaxy during the mid-1960s they faced a myriad of aerospace design challenges:
- The weight of the aircraft itself- even when empty.
- Flex in the wings, the fuselage itself, and the extended T-tail.
- How to utilize the space above the cargo hold.
- Pressurization of thousands of cubic feet of space in that cargo hold.
- Access to the cargo hold itself.
- Internal dimensions of the cargo hold required to haul specific pieces of equipment.
- Engines with enough thrust to make the entire aircraft worth building in the first place.
Answers to these and hundreds of additional challenges were found during both development and use of the Galaxy over the last 47 years. New wings, new engines, and new cockpit avionics have all been or are being fitted to the C-5 fleet. Of the 131 C-5s originally built by Lockheed about 100 of them are still in service.
One of the most interesting facets of the C-5’s design is its landing gear. Built to support a maximum takeoff weight of 840,000 pounds (that’s 420 tons to you and me), it consists of a single steerable nosegear strut and four main gear bogeys mounting a total of 28 wheels. The complex system can be a maintenance challenge but it allows for use on rough or unpaved surfaces, castoring to improve ground handling and maneuvering, and originally had the ability to “crab” for crosswind landings that has now been eliminated.
In order to simplify tire changes or brake maintenance, each set of wheels can be retracted individually. 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 down to truck-bed height and reduce the angle of entry to the forward or aft ramps.
Bonus Video: Listen to those TF-39s whine as a C-5 takes off. Watch those landing gear spin!
Bonus Video 2: Another TF-39-equipped C-5 takes off- shot from a unique perspective…look at those doors flapping!