|Aeroplane upgrades could futureproof US Air Force fleet|
By David Axe |04 October 2010
SkyLifter blimp could carry entire buildings 1,000 milesSocial network connects driversRenault goes electro-bonkers at the Paris Motor ShowEven four decades later, its dimensions are awe-inspiring. The C-5 Galaxy cargo plane, built by Lockheed Martin, is 247 feet from nose to tail. Its wings measure 223 feet across. Resting on its 28 wheels, the airlifter towers 65 feet over the tarmac. Fully loaded with up to 135 tons of cargo, the C-5 weighs more than 380 tons and can still reach speeds of up to 520 miles per hour. The biggest aeroplane in the world by some measures when the first of 127 copies entered US Air Force service in 1970, today the Galaxy has been eclipsed by the slightly larger Russian An-124. But it's still one of the biggest machines ever made.
For all its impressive dimensions, the C-5 has been a lacklustre performer. Just five years after entering service, the Galaxy fleet began to suffer structural cracks that required building all-new wings for the first 77 copies -- a process that lasted until the mid-1980s. In the meantime, the Air Force restricted the plane's payload to a modest 25 tonnes. Ten years later, the Galaxy's TF-39 turbofan engines -- four per plane providing 43,000 pounds of thrust per engine -- began acting up.
The Air Force's stated goal was that three-quarters of C-5s would be ready to fly at any moment. In reality, just over half were in flying condition. By the turn of the century, the giant plane had developed additional problems. Its avionics, state-of-the-art when designed in the 1960s, couldn't meet the UN's Global Air Traffic Management standards, meant to ensure flight safety in crowded airspace. Increasingly unsafe and often unable to fly, the C-5 was "getting old," said Lorraine Martin, a Lockheed vice president.
In 2000, the Air Force took a hard look at its biggest aeroplane. There were two basic choices: replace the C-5 with newer but smaller Boeing C-17s, or do something to fix the Galaxy's reliability and safety problems. The results of that study led directly to a cavernous hangar at a Lockheed facility in Marietta, Georgia, where today a highly-skilled workforce is using specially-developed tools and procedures to conduct industrial surgery on a steady procession of finicky old C-5s. The result is an essentially brand-new aeroplane -- and potentially a new philosophy for the world's biggest and most powerful air force.
The C-5 has forced the Americans to redefine what "old" really means for military aeroplanes. Where once planes were simply discarded after a preset number of flight hours, today with carefully considered upgrades they can keep going and going. The implications are enormous for the military, and for the taxpayers that fund it.
Diagnosis and prognosis
The Air Force's study of the C-5's health concluded three things: the aluminium airframe with the new wings had 80 percent of its life remaining; the engines, and the avionics, did not. Fixing the latter might cost $150 million per aeroplane, compared to $250 million for a factory-fresh C-17. But if $100 million bought another 40, 50, even 60 years of service for the biggest aeroplane in the Western world, it was well worth the cost, proponents argued. Against the wishes of many elected officials, the Air Force decided to buy new engines and avionics for the 52 healthiest C-5s rather than funnel that money into newer C-17s. The new aeroplane would be designated the C-5M Super Galaxy -- "M" for "Modernised."
First, Lockheed needed partners. For avionics, the Maryland-based, number-two US arms-maker tapped Honeywell in New Jersey. Honeywell would provide new radios, autopilot, collision-avoidance sensors and electronic displays to replace the 1960s-style, round dials in the cockpit. General Electric, the Connecticut-based company that built the C-5s original TF-39 engines, won the contract to provide more powerful, reliable and fuel-efficient and also quieter CF-6 engines as replacements.
Lockheed and the Air Force were bullish about the project's prospects. They estimated that the C-5M fleet would save a million dollars a day in maintenance and fuel costs compared to the unmodified C-5s. General Norton Schwartz, then chief of US Transportation Command, anticipated a big improvement in the percentage of Galaxies ready for action. "For me, 75 percent is the floor, not the ceiling," he said.
While the Air Force inspected its C-5s at eight different air bases scattered across the US, in order to find the best candidates for surgery, Lockheed prepared its Marietta facilities to receive the first giant airlifter. That meant installing tailor-made, six-story scaffolding in four of the site's massive hangars. "The scaffold looks like a web that encompasses the aircraft," Martin explained. "Our folks can work right up to the aircraft with their eyeballs next to the [wing] leading edge."
Lockheed was familiar enough with the Galaxies to know that each one would require special treatment. Over the years and thousands of flight hours apiece, the Galaxies have stretched, compressed and warped in different ways. That especially applies to the support pylons that connect the engines to the wing. "None of the original holes and fittings are in the same place from aeroplane to aeroplane," program official Jeff Armentrout said. "You must fit the new pylon very precisely. It's meticulous work ... a lot of it done by hand from inside the fuel tank" in the wing.
To get a perfect fit the first time, every time with the new, custom pylons, Lockheed brought in laser scanners capable of precisely measuring the distance between rivet holes. In total, Lockheed spent $24 million getting Marietta ready for C-5 work. Outfitted with lasers, standing atop the new scaffolding, Lockheed's 350 C-5 surgeons were ready to receive their first patient. It arrived in 2005. After the plane's leftover fuel was carefully offloaded, work got underway.
In the beginning, surgery took between 12 and 18 months per jet. The first C-5 rolled out of the hangar in May 2006 and flew for the first time in June. It and the next two Super Galaxies would spend the next three years in testing in Marietta and at an Air Force base in California. In 2007, Wade Smith, one of the engineers on the test program, reported cautious optimism. "We have no problems with the engines," he said. "The increased thrust has been very impressive."
By 2009, cautious optimism had given way to outright bragging. At a base in Delaware, the Air Force loaded up one of its new C-5Ms with 80 tons of cargo, intending to bust several altitude, payload and time-to-altitude records. In a 90-minute flight, the Super Galaxy broke 41 records, including one set in 1989 by a supersonic Russian bomber. "This doesn't happen very often ... not in one flight," said Kristan Maynard, an official from the record-keeping National Aeronautic Association.
Armentrout dubbed the improved C-5 a "rocketship." It might have taken 40 years, but the one-time biggest plane in the world was finally living up to its potential.
While the first three C-5Ms conducted tests and broke records, Lockheed kept bringing additional planes into its hangars for modification. Confidence increasing, the company said it would hire more workers to boost the production rate to 11 or more Super Galaxies per year.
Testing began shifting into war zones. In February, a C-5M delivered cargo to Iraq for the first time. And in July, two C-5Ms teamed up with eight older Galaxies for a comparative exercise delivering 100 US Army helicopters to Afghanistan from a Navy cargo yard in Rota, Spain.
The contrast between the new and old Galaxies was stark. The eight older C-5s together managed just 23 missions, compared to 23 missions for the two C-5Ms, according to Colonel Patrick Cloutier, one of the mission's commanders. The C-5Ms carried 55 percent of the total cargo, despite flying one fewer mission than their older kin. The Super Galaxy ended the 30-day operation with a 96-percent reliability rate. The older C-5s scored 82 percent. "In short, the C-5M did what it was designed to do: deliver cargo more effectively and efficiently than its predecessor," Cloutier said.
As such, the Super Galaxy promises to relieve some of the headaches associated with the war effort in land-locked Afghanistan. Owing to restrictions on shipping arms through China, Russia and Iran and Taliban attacks on convoys through Pakistan, roughly a quarter by weight of all supplies for the NATO war effort arrives by air. The air bridge accounts for a growing percentage of the cost of the war. As it proved in July, the C-5M could help reduce those costs. Not bad for an aeroplane that's older than most of the people who fly it.
"This really is a modern aircraft for a modern Air Force," boasted Lieutenant Colonel Mike Semo, an Air Force officer attached to the modernisation program. But it's a modern aircraft with its origins in the 1960s. For an Air Force that has traditionally fixated on always buying the latest, brand-new hardware -- F-22 and F-35 stealth fighters, C-17 cargo planes, killer drones -- the C-5M is a powerful reminder that newer isn't always better. With the right design and some careful surgery, old aeroplanes can evolve.