Wednesday, September 16, 2015

The complexity of operating the USAF's biggest freighter

There's a fascinating article over at Foxtrot Alpha titled 'What It's Like To Fly America's Biggest Jet, The Gargantuan C-5 Galaxy'.  It goes into great detail on how one gets to fly it, the sort of missions it undertakes, the current modernization program for the jet, and many other aspects of the plane.

A C-5 Galaxy swallows the fuselage of a smaller C-130 Hercules freighter

What I hadn't realized was how extremely complex the planning, preparation for and execution of a C-5 mission can be.  It involves far more than just the flight crew.  Here's an excerpt giving more details.

The C-5 is also a massive demonstration of the coordination required to do any mission. There will be multiple pilots, engineers, loadmasters and crew chiefs on every mission. The pilots primarily maneuver the airplane. The engineers are key, they know the ins and outs of every system on the plane and how to make it work best. They control the fuel balancing, the pressurization, cooling and the expansive high pressure hydraulic systems. They also calculate the takeoff and landing data for the pilots. They are super smart and I could not do their job.

The loadmasters are masters of their craft, knowing how to build a load onto a jet in the most efficient and safe manner, along with complexities like if there are multiple destinations for the cargo and how to arrange it so that it can be unloaded efficiently. They regularly have to use trigonometry to create nests of chains to distribute the weight of strange shaped or super heavy cargo so that it won’t move in any axis in flight. They figure out how the airplane needs to be configured to load and unload best, does it just need to stay as is, or level kneel so that the bottom of the jet is only inches from the ground, or forward kneel to create a smoother ramp surface to unload rolling stock.

The crew chiefs are flying representatives of our ground maintenance and the airplanes are their babies. They know how to fix any of our problems and how to interface with the local maintenance to get the jet fixed and back on the road in a timely manner. Along with all the aircrew, the C-5 relies on all the various types of ground crews, from the airmen that empty the latrines to the ones that refill the liquid oxygen and nitrogen systems and who replace our tires, to the ones in base ops that file flight plans and provide weather and knowledge about the locations we’ll be going. It’s a complex undertaking to get a C-5 mission on the road and it takes the teamwork of many personnel in order to ensure that the mission occurs successfully. Overall, our support is awesome.

There's more at the link, along with many photographs and a video clip.  Very interesting reading for aviation buffs, and of real value for those interested in military logistics.



Murphy's Law said...

I saw some of this behind-the-scenes stuff when the C-5s were based at my airport. Every take-off and landing was a big production deal, and I nmiss them, both because they were awesome to watch fly and because they rarely flew, which meant that I had unfettered access to their huge runways.

BobF said...

When I joined the Air Force I was assigned to a B-52 maintenance outfit and couldn't believe something that large could fly, never mind loaded with bombs. Year later I was assigned to C-141As and C-5As. Working on, and year later later load planning, the C-5 was an experience all itself. The bird was a test bed of sorts for a few systems that garnered a lot of groans, but all in all it was a hell of a bird. And then they began later generations after my time. Except for wiring problems and having to go up the T-tail I loved that bird.

AuricTech said...

"He ain't heavy; he's my brother."

Anonymous said...

Generally called a static display due to the fact that they fly one sortie and then sit for days waiting for parts. They pretty much were a program that was an operational failure/mistake, but I wasnt around in the early days so I dont know the details.

In cargo there is a significant difference between bulk and gross. While the C5 can do bulk (large size objects) it is a relative lightweight in terms of gross (max gross load weight). I think it is only about a 600,000# t/o weight aircraft while the 747 went up to 833,000#.

Surprisingly, as far as pilot jobs, the C5 was considered the kiss of death wrt flying career. While it was probably fun to fly, see static display above.

lpdbw said...

I did flight following software for all the MAC (later AMC) non-classified airlift.

C-5 planning meant long logistics tails for the spare parts, mostly engines.

The joke was 2 sorties per engine replacement.

When they decommissioned the C-141s before the C-17s came fully online, we didn't know how we were going to get enough airlift.

Wandering Neurons said...

C-5 used to be maxed out takeoff at 769,000, max landing 840,000. Yeah, go figure. Emergency Wartime Takeoff was 840,000. Now with the new engines and other mods, the regular max TO GW is now the old EW weight of 840k. Figure two M-1A Abrams tanks @ 125,000 each plus their support crew. 332500 lbs of fuel max, all in the wings, 375,000 lbs empty weight. 1500 lbs of liquid nitrogen for fuel inerting.
I spent five years as a Flight Engineer on the planes during the first half of the '90s. Desert Storm, Desert Shield, Somalia, Armenia, South America, Roswell, NM, and a bunch of other really cool places. Low level, airdrop, NVG qualified.
Maintenance was always a problem, especially as money was shorted as a means to force adoption of the C-17. But with qualified maintenance, the planes could fly quite well.
The article was actually very good, though told by a very new barely-qualified crew member. There's some really good stuff on that site.