Tests of newly upgraded C-5 Galaxy airlifters, which were wrapped up in January, have proved that the giant aircraft can be rendered operationally relevant for several decades to come. The results, in conjunction with a soon-to-be-released major mobility study, may reopen debate about the proper mix of strategic lift aircraft.
The operational evaluations were conducted throughout late 2009. They demonstrated that C-5s equipped with new engines, new avionics, and about 70 other improvements will climb faster, fly farther, and break far less often than the standard Galaxy.
A C-5M is heavily modified with new engines and more than 70 other improvements.
This gives the Air Force a more reliable and useful asset. In fact, the improved C-5s broke many aeronautical records with a large payload, and made dozens of trips to the Middle East without interim stops or enroute aerial tanking. The results have impressed the Air Force leadership, which may reconsider its C-5 strategy later this year.
“The tests thus far have been very positive,” said Air Force Chief of Staff Gen. Norton A. Schwartz in late January.
Plans call for the Air Force to submit its final C-5 operational test report sometime this month. Schwartz noted that it will be considered in light of the new Mobility Capability and Requirements Study, to determine just how many C-5s USAF will seek to retain, and how many of those get re-engined.
The last major mobility study, completed in 2005, talked about roughly 300 airplanes in the strategic lift fleet, noted Schwartz. When the new MCRS is complete, he went on, “we’ll make a determination—based on cost of operations—on what’s the right mix, and how do we maintain the right number of platforms that will provide the reliability and cost of operations that we can effectively carry forward.”
In other words, the Air Force will try yet again to find the right balance between new C-17s and upgraded C-5s, modified for extended service lives.
The C-5 fleet was divided into two main batches: the C-5As, which date back to the 1960s, and the C-5Bs, which were built in the 1980s. Two C-5Cs, converted from C-5As, are specially configured to carry exceptionally large cargo, such as rocket sections.
All C-5s are getting an upgrade called the AMP, for Avionics Modernization Program. The AMP provides modern navigation and communication equipment so that C-5s can function in modern civil-controlled airspace around the world. The AMP also provides a “digital backbone” for the airplane, solving many reliability problems stemming from analog electronic systems that are obsolete, and for which parts are no longer available. In the cockpit, pilots now have modern flight controls and amenities such as moving map displays and color multifunction displays to replace vast rows of “steam gauges.”
The AMP is the prerequisite for the second, more elaborate upgrade, which for now is only being performed on the younger C-5Bs. That second upgrade is the RERP, for Reliability Enhancement and Re-engining Program. The RERP replaces the C-5’s old engines with a new variant of the General Electric CF6, which is employed on large commercial aircraft such as the 747 and 767 and USAF KC-10. The new motors provide far more power, and require far fewer overhauls and service events, meaning the RERP will greatly reduce the C-5’s downtime.
Lt. Col. Michael Semo, C-5M program officer at Dover AFB, Del., noted that the new engines only need to be taken off the airplane every 10,000 hours for a major service, versus 2,000 hours for the existing engines.
“Multiply that by four engines per aircraft, ... and you see that this is a tremendous improvement in capability for us,” he said. “That translates directly into a better mission capable rate.”
Most problems that plague unmodified C-5s can be chalked up to engine headaches, although there are many other “bad actors” that hobble the aircraft as well. The RERP encompasses about 70 improvements, ranging from engine replacement to structural, hydraulic, and electrical enhancements, flight controls, and landing gear.
Shown, back to front, are a C-5, C-17, and “stretched” C-130. Modified with a major upgrade, C-5Ms like the one below broke time-to-climb records and moved massive amounts of cargo in a surge exercise.
Aircraft that have received both the AMP and RERP upgrades are now designated C-5M.
In January, there were 59 C-5As, 46 C-5Bs, two C-5Cs, three C-5Ms, and one well into conversion, for a total of 111 aircraft.
The Air Force began its own internal debate on what to do with the C-5s a decade ago. The aircraft at that time were poor performers, with mission capable rates dipping as low as 50 percent. The somewhat smaller C-17 offered an attractive capability in a brand-new airframe, able to carry outsize and oversize gear directly to shorter forward airstrips where the C-5 could not go. It was also assumed that the C-5As, already several decades old, were not worth updating because of their age.
However, fleet viability assessments showed that the C-5s were not really in very bad physical shape, despite their age. In 2004, a physical teardown analysis of a C-5A confirmed that the Galaxys had a probable life of more than 45,000 flying hours when they were built, of which about half has been consumed. Destructive testing of a C-5A in 2006 found no major structural problems.
“This aircraft is going to fly to 2040. Or beyond,” said Lorraine Martin, Lockheed Martin vice president for the C-5 program. “2040 is really the minimum that they did the analysis against, but it can fly past that.”
Once it was determined that the C-5 could go the distance, structurally, it remained to be seen whether the planned improvements in the RERP would actually deliver the on-time reliability and improved efficiency USAF needed to see to justify the upgrade as worthwhile. However, development costs of the RERP began to climb, and the project was deemed to be in breach of the Nunn-McCurdy Act, a law that stipulates that programs must be terminated or restructured if their costs grow unacceptably. The Pentagon responded by slashing the scope of the RERP to the C-5B models only. The C-5As, top Pentagon leaders decided, would get only the AMP to render them able to operate safely under new global air traffic management protocols.
While the RERP appeared to be in trouble, Congress continued to add C-17s to the Air Force’s budget, even though the service did not request them and maintained that it only needed around 300 strategic airlifters, based on the 2005 mobility study.
When he was head of US Transportation Command, Schwartz in 2008 told Congress that the Air Force would have to cut back on something else if it were to afford the operation and maintenance of the unrequested C-17s.
“If you build above 205 C-17s,” Schwartz said in budget testimony two years ago, “it means taking capacity out elsewhere, which probably means C-5As.” Congress banned the Air Force from retiring any C-5s until the RERP testing was completed. In the meantime, Congress funded the Air Force for 223 C-17s, about 50 more than when the service first said it had enough.
This year, Schwartz seemed not to have changed his mind about reducing the size of the strategic fleet.
(Lockheed Martin photo)
“I would say, we’re going to retire some C-5As,” Schwartz said in January, before the 2011 defense budget was unveiled. “Certainly, we’re going to propose that, both to the leadership in the Pentagon and on Capitol Hill.” However, he added that “it is not necessarily a closed door what will happen with the remaining aircraft that will stay with us some number of years,” indicating that the Air Force may, indeed, petition to have the C-5As reinstated in the RERP.
As a surge test in the four-month operational evaluation, the three initial examples of the C-5M—one converted C-5A and two converted C-5Bs—flew 34 sorties in 31 days, flying war supplies directly from Dover to Incirlik AB, Turkey. They moved so much cargo—3.8 million pounds—so fast that Incirlik became bottlenecked; the Air Force couldn’t move the supplies on to their final destinations in-theater as quickly as the C-5Ms were bringing them in.
The on-time and surge performance was unprecedented for C-5s, long notorious for takeoff delays and scrubbed missions due to system breakdowns. However, the fact that the Incirlik missions were flown directly signified a new capability. A C-5A or B would have made a stop in Spain or required an aerial refueling tanker en route, or both, with a need for additional air and ground crews and the likelihood of an on-ground maintenance problem along the way—and at either end.
Versus unmodified C-5s, the C-5Ms saved more than 354 hours by going directly—nearly 15 days of additional capacity. Avoiding the enroute stop and flying at more efficient altitudes also saved 1.32 million pounds of fuel, or nearly 200,000 gallons.
“We achieved 103 percent mission reliability,” said Semo. “We had 33 missions scheduled and flew 34” in the time allotted. The cargo flown was mostly “pallet trains” that roll on and roll off.
“That’s what modern technology engines do for you,” said Schwartz. The improvement was “significant,” he said.
Capt. Cory Damon, a C-5 pilot and a participant in the surge test, said, “This is the C-5 you’ve always wanted. ... The performance is fantastic.”
All programs are judged against what are called Key Performance Parameters, or KPPs. In the case of the RERP, the C-5Ms met all those required performance marks with room to spare. Mission capability, for example, had to be raised from the 50-to-60 percent range to 75 percent or better, which would bring it in line with USAF’s standards. During the Air Force Operational Test and Evaluation Center tests, the C-5M racked up a 77.4 MC rate and a 94.4 percent launch rate.
The modified aircraft beat by nearly five minutes the required 25 minute climb to 31,000 feet on a hot day with a large payload, allowing them to rapidly reach what Damon called “the sweet air” of favorable flying altitudes. They surpassed the noise and emissions requirements of the FAA and foreign aeronautic agencies, achieved a break rate of 8.5 per 100 sorties, against a requirement for 10.5 or fewer, and surpassed the repair rates after four, 12, and 24 hours by a comfortable margin.
MSgt. James J. Busbea, a C-5M flight engineer involved in the operational test and evaluation, said the C-5A which was converted to a C-5M “in the surge, did as well as the [converted] B models.” There were only “minor differences” in repair of the two flavors of C-5M, he said.
The results—which were still unofficial in late January—more than met the minimum performance USAF demanded in order to win approval to go ahead with modifying a significant portion of the C-5 fleet.
A1C Justin Fleming (l) and Amn. Alisha McKinney change a fuel probe on a C-5’s wing. Galaxys receiving new engines will require fewer maintainers.
Not a No-brainer
In January, Pentagon acquisition chief Ashton B. Carter approved completion of the first low-rate initial production aircraft in the RERP. His actions gave the green light to finish three aircraft, start modifying five more, and buy parts for modifying a further seven.
“What’s been most satisfying to me is that the operational results we’re seeing today really do match or exceed what our engineering models were telling us back when we were designing this program,” said Lockheed Martin mobility programs vice president Jim Grant.
“What we’ve seen with the first three test airplanes, and what we’ve seen in production now, is that ... those predictions are in fact accurate.”
Quoting an Air Force estimate, Grant said the C-5 RERP “pays for itself” over the coming decades, based on the reduced cost of ownership and reduced usage of fuel.
Because it is a larger airplane than the C-17, the improved C-5M can also now fly farther than the C-17, while carrying twice the number of pallets and, in most cases, twice the number of outsize vehicles such as mine-resistant, ambush-protected all-terrain vehicles (M-ATVs), Apache helicopters, tanks, or armored personnel carriers.
By January, 60 C-5s had received the AMP, at program acquisition unit cost (in 2006 dollars) of $12 million apiece, and an average unit cost of $8 million (the first number includes research and development and facilitization; the second is the cost of just buying and installing the upgrade). The RERP, in 2008 dollars, costs $136 million a copy including R&D, and $109 million without counting start-up costs.
Congress has compared the AMP and RERP on the C-5—between $117 million and $148 million each, depending on how you count—against the cost of a brand-new C-17, with a pricetag of between $200 million to $250 million a copy. So far, it has funded both.
Applying the RERP to the C-5As, however, is “not the no-brainer it would appear,” a senior Air Mobility Command official said.
Speaking on background, the senior official noted that the current schedule will not modify all the C-5Bs to C-5M configuration until 2016. At that point, he said, the C-5As will have aged another decade since the teardown analysis that evaluated their remaining life.
A Galaxy is masked in preparation for paint removal. Sharply improved C-5 reliability will give USAF the equivalent of dozens more airlifters.
“We will have to see, in six years, whether that would still be an economical use of dollars, which we will not have in unlimited supply,” the official said.
Gen. Duncan J. McNabb, head of TRANSCOM, said a year ago that he would be happy to “grow the force structure a little bit” with the increased capability that would come with performing the RERP on the C-5As as well as Bs. The additional capability could help offset the heavy use of C-17s, whose service lives are being consumed at a much faster rate than planned, he told a House Armed Services subcommittee. However, the extra RERPs would only be possible if the cost of the modification continues to come down.
That could happen. Lockheed Martin has been very aggressive in pursuing cost reductions on the RERP, Lorraine Martin said. In the cavernous hangar at Lockheed Martin’s Marietta, Ga., plant where the RERP is performed, scaffolding has been erected all around the C-5s receiving the modification, as well as within them. Everything workers need to do their job is at their fingertips; otherwise, they would have to climb down and then up what amounts to a seven-story building to get parts and tools. It’s part of an overall effort to find any time or process savings possible.
Jigs have been created that reduce alignment time of some parts from weeks to hours, Martin noted. In each of the four spaces available for the RERP in Marietta, the company has invested $6 million to streamline the process, she reported.
“The savings we’ll see, not only in touch labor but in time, are going to be fairly dramatic,” she said. “We expect to get the 12-month process that we’re using on this aircraft down to eight months when we’re at full rate. That’s a fairly significant benefit, getting the aircraft back in the fight four months earlier.”
Lockheed Martin will ramp up to a rate of 11 C-5M modifications per year at Marietta. It is using the same hangar space to do the RERP as it did in assembling the behemoths 25 years ago.
One of the first C-5s, circa 1970, in the “European One” camouflage scheme. The C-5s are now expected to serve to 2040 at least.
Low Hanging Fruit
She said the RERP contract is of the “fixed price, not-to-exceed” variety, meaning it behooves Lockheed Martin to make as many efficiencies as it can. If cost reductions are substantial enough, the government and the company will each share in the savings.
Martin said that in working on the As and Bs, the only apparent difference is that “the wiring is a little older” in the As, but Lockheed has found no major differences in the condition of the As and Bs. The aircraft, however, are inducted for the RERP upgrade having already gone through the AMP and a programmed depot maintenance, which is in itself a comprehensive overhaul.
The build rate of 11 C-5Ms could be increased, Martin said.
“We would love [to have] a higher build rate ... to have a more efficient line. And we’ve already shared our thoughts with the Air Force either for the current program, if things were to change for them, or if they want to add additional aircraft.”
She said that Lockheed Martin could “add a couple easily” to go up to around 13 RERP aircraft a year, “or we could start earlier. We don’t get to 11 until five years from now; we could start that earlier and we could add a couple of aircraft. If we wanted to go higher ... than 11 plus two or three, then we would look for additional infrastructure,” since the giant hangars at Marietta would be full-up. She said the company has explored using facilities in other locations around the country “that are well-suited for C-5 maintenance, size-wise.”
The most that could be done would be 15 to16 a year without adding more facilities and people to the process, Martin said.
The C-5M converted from an A model “performs just as smoothly” as the two converted from C-5Bs, Martin said, “so it’s a capability that’s there for the Air Force, Guard, or Reserve to use those aircraft, should they decide to do it.”
The 70 or so items included in the RERP did not capture the entire list of things the Air Force wanted to improve on the C-5; some were left off to make the program more affordable. Those items not making the cut included landing gear modifications and other “low hanging fruit” that the C-5 depot, Warner Robins Air Logistics Center, Ga., is considering “as they go through their sustainment and supportability working groups with AMC,” Martin noted.
The C-5s are also being fitted with the Large Aircraft Infrared Countermeasures (LAIRCM) system to give them protection against heat-seeking missiles. Without the countermeasures, they could only be flown to the most secure airfields, but the addition of the self-protection system will allow the C-5s to operate anywhere the Air Force has a runway of sufficient size. The LAIRCM is also being installed in Marietta.
The senior Air Mobility Command official said his organization has only done some preliminary planning for how the C-5M will be utilized in the force.
“Certainly, it will be able to go more places, ... more hot, high fields,” though not necessarily shorter fields. He said, “It’s really too early to think along those lines until we get the MCRS and know how many slots we’ll have available.” However, even if the C-5M is used “in just the same way” that AMC has used the C-5As and Bs, “we will be saving a whole [lot] of gas, and that will be a huge force multiplier in the years to come.”
Read the day's top news on the US Air Force, airpower, and national security issues.
Daily Report: Read the day's top news on the US Air Force, airpower, and national security issues.
Tweets by @AirForceMag