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Sunday, June 1, 2008

Aviation Maintenance: Military: Rebirth of a C-17

Allan T. Duffin

Allan T. Duffin is a freelance writer, television producer and veteran of the U.S. Air Force. As a maintenance squadron commander, he deployed to Southwest Asia for Operations Iraqi Freedom and Enduring Freedom and received the Bronze Star for outstanding leadership in a combat zone.

Engineers, maintenance crews turn crippled aircraft into fleet workhorse.

The gigantic cargo plane descended onto the 12,000-ft. runway in the middle of a dusty, barren plain. The aircraft was a C-17 Globemaster III, the relatively new workhorse of the U.S. Air Force. The wheels touched down on the asphalt, and suddenly the plane began to roll off the runway, striking part of an aircraft arresting system. Veering right, the C-17 then hit a three-foot-high dirt berm. The nose gear collapsed and the right main landing gears were damaged. Finally the airplane ground to a halt, its fuselage resting on the dirt berm and the port wing hanging over the edge of the runway.

Fortunately, none of the crew aboard the C-17 was injured. The airplane, on the other hand, was in poor shape. The accident rendered it unflyable; the loss of the landing gear had resulted in massive structural damage to the nose and fuselage. Worse yet, the incident occurred at Bagram Air Base in eastern Afghanistan — right in the middle of a combat zone.

Rescuing a Wounded Bird

A recent addition to the Air Force inventory, the C-17 replaced the aging C-141 Starlifter as the primary strategic airlift platform for cargo and troops. The Globemaster can also perform airdrop and aeromedical evacuation missions and is designed to use runways as short as 3,500 ft. Bagram Air Base, site of the C-17 accident, is located in eastern Afghanistan, 25 miles north of the capital city of Kabul. The Air Force unit stationed there provides airlift and close air support for military operations on the ground.

With a Class A mishap (damage estimated at $1 million or more) on his hands and combat missions waiting to use the blocked runway, the base commander at Bagram needed to relocate the crippled C-17 as quickly as possible. Army and Air Force personnel rushed to the aircraft to survey the damage and figure out what to do.

Meanwhile, at the airplane’s home station of Charleston Air Force Base (AFB), S.C., Ken Crumpler received a phone call on Aug. 6, 2005 in the middle of the night. Crumpler, an engineering manager, was responsible for Boeing’s field service engineers. "We’ve had a C-17 incident at Bagram Air Base in Afghanistan," he was told. Crumpler immediately got to work.

While the Air Force performs day-to-day operations on the C-17 fleet, Boeing takes care of repairs, supply issues and depot maintenance through its Globemaster III Sustainment Partnership, or GSP. The contract, estimated at $4.9 billion, provides worldwide, round-the-clock support of the 150 C-17s in the Air Force inventory. Boeing has engineers stationed at Ramstein Air Base in Germany, plus others who rotate through Al Udeid Air Base in Qatar and Incirlik Air Base in Turkey.

Jon Buresh, GSP program manager, is a former Naval aviator, maintenance officer and 23-year Boeing employee. "We’re paid by how well the C-17 fleet performs," he says, "and we’ll do whatever it takes to support this aircraft."

And so they did. Within 24 hours of the C-17 accident, Boeing engineers from Ramstein and Charleston traveled to Bagram Air Base to conduct an initial damage survey. Before the week was out a team comprised of five Air Force and 12 Boeing personnel, including Crumpler, arrived at Bagram to assist with the recovery. The Boeing technicians came from the company’s Recovery and Modification Services (RAMS) team, trained to assist with rescuing damaged aircraft; while the Air Force personnel were battle damage repair specialists from Charleston and the Warner Robins Air Logistics Center in Warner Robins, Ga.

Together the military and civilian teams carefully maneuvered the crippled C-17 off the runway using a crane and a flatbed trailer, which served as a wheelchair for the broken landing gear. Because the aft door was unusable due to the tilt of the aircraft, 55,000 lbs. of cargo were removed, piece by piece, through the crew door. Engineers clicked together metal airfield matting over the ground to keep their makeshift system from slipping, then nudged the C-17 back onto the runway and over to a parking spot.

A Careful Return Home

Next came a fateful question: What should be done with the airplane? The nose had buckled so severely that it looked like one-third of the aircraft would need to be rebuilt. The Air Force considered its options, including scrapping the C-17 outright — a $200 million loss. Crumpler and the Boeing engineers wanted the chance to put the airplane back together.

The only way to repair the C-17 would be to limp it home to its birthplace — the production line at Long Beach, Calif. — where Boeing personnel could patch the fuselage back together properly. It would be expensive, but nowhere near as expensive as replacing the aircraft with another one. Rather than scrap the airplane, the Air Force gave Boeing the go-ahead to rebuild it. "We closed all of the gaping holes and got the aircraft back into shape so it could fly," says Crumpler.

Battling desert winds that raced up to 40 kts. (about 46 miles per hour), the Boeing team worked with local military personnel to stabilize the C-17 and identify recovery equipment, tooling and parts that were needed to bring the crippled airplane back to minimal flying standards.

Finding the right tools took some ingenuity. "We went to the boneyard, borrowed tooling from the MD-11 (which last rolled off the assembly line in 2000), and modified it for the C-17," says Crumpler. Also adapted for the C-17 was specialized tooling that Boeing had previously used to convert passenger airliners into cargo planes. Everything was collected and shipped to Bagram.

On October 16th — 72 days after the aircraft had fallen off the runway in Afghanistan — the C-17 took to the air, followed by a KC-10 tanker serving as a chase plane. During the next five days an Air Force crew hop-scotched the C-17 across the globe: to Al Udeid Air Base in Qatar; the Naval air station at Sigonella, Spain; Lajes Field in the Azores; and finally across the rest of the Atlantic Ocean to its home station, Charleston AFB. There the C-17 was serviced for the final leg of its flight to Long Beach, Calif.

When the C-17 — known to Boeing by its production number, P-96 — touched down at Long Beach, technicians were slightly apprehensive but ready to go. Crumpler notes that the GSP program has its own hangar — on the opposite side of the runway from the production line hangar — where Boeing accomplishes minor repairs on C-17s. "But this was not a minor repair," says Crumpler. Technicians were brought in from various Boeing locations across the country to supplement the experts at Long Beach.

Unbuilding and Rebuilding

The project team held twice-daily meetings to review progress on the damaged jet. "My job was to make sure we had all the right people there as fast as they were needed," says Buresh. "We had to get engineering support and talk to our manufacturing people. We asked ourselves a lot of questions: How do you take out a part? How do you unbuild an aircraft and then rebuild it?"

The first step of the process required gutting a portion of the aircraft. "We took out a 20-ft-long section of underbelly out," Buresh explains. As manufacturing technicians "unbuilt" the fuselage, engineers kept careful watch to ensure that no further damage was inadvertently being done to the nose. Every part removed from the C-17 was laser-leveled to avoid decompression, tension or stress.

During the next 10 months Boeing personnel carefully rebuilt aircraft P-96. Boeing’s records reflect the massive undertaking, listing as needing repair the "lower fuselage area, 11 ft. by 28 ft.; Sta. 227 bulkhead; forward and aft right hand main landing gear assemblies; nose landing gear assembly; and the right hand forward pod." No one had ever attempted a C-17 repair this extensive.

Parts were manufactured as needed, from wherever they were needed. "The biggest major assembly we had to rework was the barrel assembly, a huge underbelly structure that’s made in Macon, Ga.," recalls Stan Perez, a modification development specialist who served as a project manager and was tasked with the unenviable job of estimating and tracking the overall budget.

The second major assembly that Boeing had to manufacture was a new right-hand pod to replace the one that crumpled when the C-17 rolled off the runway at Bagram. That part would be assembled in St. Louis, Mo. "We coordinated with management at two Boeing facilities and worked out a schedule to build these assemblies without interrupting other production flow," explains Perez, a former Navy maintainer with 33 years in the aviation business. "We did the same thing with smaller assemblies like line replaceable units (LRUs)," he adds.

The parts were then shipped to Long Beach, where 53 Boeing employees — technicians, quality inspectors, managers and asset managers — worked two shifts a day, seven days a week, to rebuild the airplane. Air Force oversight came from the local Defense Contract Management Agency (DCMA) office. On the factory floor, P-96 waited as 15 mechanics on each shift flitted around its damaged fuselage. "A lot of folks were moving parts back and forth," describes Perez, "replacing bad ones for good ones." Skin panels, clips, huge assemblies — piece by piece, maintainers accomplished the painstaking work of putting the aircraft back together.

When the repair team had completed its work, the aircraft was repainted in the Air Force’s characteristic gray camouflage color. Then it was time to put the aircraft through its paces. To return to the Air Force’s active fleet, P-96 had to prove that it was as robust as any brand-new C-17 rolling off the assembly line. Among the tests completed were three check flights to test aircraft systems.

Just Like New

After 10 months, 88,500 manhours and the installation of more than 5,000 parts, Boeing was ready to re-deliver the aircraft to the Air Force. Total cost: $25 million — one-eighth of what it would have cost the Air Force to replace the entire aircraft. Better yet, the complex project finished under budget. "Looking at P-96 today, you wouldn’t have a clue what this airplane has been through during the last year and three months," said Buresh at the time. "It was a wise investment for the Air Force."

On November 17, 2006 — 15 months after the accident — employees at Boeing’s Long Beach facility celebrated the rebirth of P-96. "It looked just like a brand-new aircraft that had just come off the factory floor," says Perez. During the delivery ceremony, the C-17 was unveiled with a new name stenciled on its nose: Spirit of Enduring Freedom.

Lt. Gen. Christopher Kelly, commander of Air Mobility Command, the organization accepting the aircraft back into its fleet, attended the ceremony on behalf of the Air Force. "‘We can, we must, we will’ — you have truly said those things in the craftsmanship and attention to detail, most importantly the grit and determination you showed in bringing back to life P-96," he told the Boeing staff.

The reborn airplane, a phoenix of metal and glass, lived up to its reputation. During its first six weeks back in the lineup, Spirit of Enduring Freedom chalked up a 92.3-percent mission-capable rate over 54 missions and 86 sorties. For fiscal year 2007, the airplane scored an 86 percent mission-capable rate, among the best in the C-17 fleet.

And in July of last year, Spirit of Enduring Freedom arrived at McChord AFB in Washington to compete in the Air Force’s annual Rodeo event, which pits aircraft and their crews in more than 60 competitions. The airplane’s owners, the 437th (active duty) and 315th (associate reserve) Airlift Wings, took home the award for Best C-17 Maintenance Team — a fitting tribute to the men and women who maintain the C-17 every day.

Today aircraft P-96 is fondly remembered by the people who spent over a year stitching its fuselage back together. "This project was the most exciting thing in my maintenance career," says Buresh. "We took an aircraft that was going to be scrapped with a forklift and turned it into one of the best-performing aircraft in the fleet."

Neal Freeman and Bradley Mudd of Boeing contributed to this article.

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