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Geriatric Aircraft

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This an excellant Navy League document that highlights the problems the Navy is having with its aging aircraft.

http://www.navyleague.org/sea_power/nov06-31.php

Aircraft Geriatrics

With the oldest fleets in naval service history, the Navy and Marine Corps adopt new tactics to keep their aircraft flying

By OTTO KREISHER, Special Correspondent

Pilots of the Navy’s electronic warfare aircraft were told in recent years not to maneuver their planes aggressively, and the Marine Corps’ 40-year-old CH-46 helicopters were placed under weight restrictions for months. The Navy today is struggling to keep its P-3C Orion patrol planes flying despite fatigue cracks and other maladies that threaten to curtail their remaining years of service.

These are among the problems facing the Navy and Marine Corps as they deal with the geriatric condition of their 3,880 aircraft, which now comprise the oldest aviation fleets in their history.

With no hope of procuring enough new planes to lower the fleets’ age profile in the near future, the two services are adopting several tactics to keep their existing aircraft flying effectively and safely despite their age and the continued stress of operations in Afghanistan and Iraq. Older aircraft are being retired, others have been fitted with new engines and the services are applying special tapes and coatings to the vital parts of aircraft operating in the fine sands of Afghanistan and Iraq.

The inventory of Navy and Marine aircraft has an average age of about 18 years, said Robert P. Ernst, director of the Aging Aircraft Integrated Product Team at Naval Air Systems Command (NAVAIR). It rose from an average of about 14 years in the mid-1980s mainly “because we didn’t buy that many (aircraft) in the 1990s,” said Laurence Stoll, a former NAVAIR official now a consultant to Ernst’s team.

And just as individuals pay more in medical bills as they age, old aircraft become increasingly more costly to keep flying.

Nick Kunesh, deputy assistant Navy secretary for logistics, said, “As things age — weapon systems, moving parts, electro-mechanical, electrical parts — they become more and more difficult and costly to repair.”

Maintaining and replacing electronics and avionics is “the biggest cost driver,” he said.

Retired Adm. Vern Clark, the former chief of naval operations, believed that the cost of operating aging ships and aircraft was consuming money needed to recapitalize, or buy new equipment, and initiated programs to retire the oldest planes in the fleet.

However, Ernst said, “we can’t sacrifice today’s readiness for tomorrow’s recapitalization.”

For example, returning the EA-6B electronic warfare plane and the CH-46 helicopter to a higher operational status cost hundreds of millions of dollars. Marine Lt. Col. Harry Hewson, program manager for the CH-46s, said the services spent a total of $408.6 million to upgrade the rotor and engine drive train and remove the weight restrictions.

The CH-46s also are going through a $281.3 million Engine Reliability Improvement Program that will almost quadruple the time between engine replacements, reducing the load on maintenance personnel, Hewson said.

The average age of the naval air fleet peaked in about 2002 and “may drop a bit, not because we bought our way out … but basically because we retired some of our older aircraft. We’ve downsized some of the fleet, waiting for recapitalization,” Ernst said.

But the problems of the Navy and Marine Corps are not as severe as those of the Air Force, which has an air fleet with an average age of 23.6 years, pushed skyward by its KC-135 airborne tankers and B-52 bombers that are approaching 50 years of age.

The age of the Air Force fleet continues upward, due in part to congressional restrictions against retiring 1,033 of its oldest aircraft that are the most costly to maintain, including C-130s, C-5s, KC-135s and B-52s.

Those aircraft are the main rationale for the continued existence of some air bases, and members of Congress blocked their consignment to the military’s airplane boneyard, fearing their loss would make the bases vulnerable in last year’s Base Realignment and Closure process.

There were no similar restrictions on the Navy and Marine Corps, largely because their planned aircraft retirements would not have left any air station without a significant mission.

Thus, the Navy has retired a large number of aircraft, including all of its F-14 Tomcats, most of its S-3B Vikings and nearly all of the Navy Reserve’s P-3Cs.

In a session with reporters this spring, Adm. Michael Mullen, the current chief of naval operations, said of the Tomcats and the Vikings: “Those are two airplanes … that served exceptionally well but were extraordinarily expensive to keep up, which was one of the reasons that we needed to get rid of them.”

And despite retiring many old Orions, Mullen said the P-3Cs are “the part of my aircraft fleet I am most concerned about.”

Ernst agreed that there was “a huge issue with some of our P-3s … to try to keep them viable until the P-8 gets here.”

Initial units of the Boeing-built P-8 Multimission Maritime Aircraft are expected to be deployed in 2013 but will not replace all of the P-3Cs until about 2023.

To fill that gap, Ernst said, “the P-3 community did a full-scale fatigue test and SLEP,” or service life extension program, enabling the Navy to anticipate some of the aging problems, retire older aircraft with fatigue cracks or other service life issues and reconstitute a smaller, more capable fleet.

For the longer term, the preferred solution is “to really recapitalize the fleet and to get down to some numbers we’d like,” such as an average age of about 16 years.

To do that, naval aviation would have to procure about 170 aircraft a year, but is only buying 125-130.

The Navy’s 2007 budget projected an increase in aircraft procurement from 134-269 annually by fiscal 2010. But earlier projections of increased buys have been reduced due to continuing budget constraints and development problems with the replacement systems.

Mullen has ordered a detailed study to determine the size and shape of the future aviation force, similar to that which produced the current 30-year shipbuilding plan.

Ernst cautioned that age is not really an accurate metric of the problem because, for example, the services utilize their aircraft in different ways. Fleet operators tend to pick their newer, more capable aircraft for deployments, wearing them out faster than older planes, which have endured fewer flying hours.

Moreover, the operational costs of newer platforms may be higher than for older models because the avionics are obsolete. That is caused partly by the rapid evolution in electronics and computers in the commercial world and the military’s increasing use of commercial-off-the-shelf products.

In the past, electronic components would remain in production for 10-15 years, making it easy to obtain replacements, Ernst said.

“We’re now seeing microcircuits going out of service in two or three years, requiring us to do a tech refresh probably every seven or eight years,” he said.

“You could have an aircraft that has lots of fatigue life (or flying hours remaining) but can’t do anything because you can’t get the avionics repaired.”

Aircraft aging also is affected by other factors, including different theaters of operations. A prime example is the prolonged operations in places such as Iraq, Afghanistan and Kuwait where the sand wreaks havoc with helicopter rotor blades and aircraft engines, avionics and wiring.

“We’re seeing some early failure modes because of the deployments into Southwest Asia,” Ernst said.

The U.S. military learned of the harm sand can do as far back as the failed rescue of American hostages at the Embassy in Tehran in 1980 and in Operation Desert Storm in 1991. But those operations lasted one day and several months respectively, compared to five years in Afghanistan and three in Iraq, Ernst said.

Today, the services are struggling with “two different environments, two different sand types” that affect aircraft and their components differently, he added.

Because those problems affect all of the armed services, they formed the Joint Council on Aging Aircraft, which Ernst chairs, to solve them.

“The first thing we had to figure out was what was kicking our butts over there,” he said.

The goal was to analyze the different types of sand in the region, develop a model to predict its effects on aviation systems and look for new technologies to alleviate the problems.

Remedies included better inspection methods, new ways of cleaning out wiring bundles, changing the aircraft washing procedures and applying coatings to the leading edge of helicopter rotors.

Marine Col. David Dowling, program manager for the CH-53 helicopters, said the Corps also conducted an engine reliability program to deal with the sand problems, which included a titanium nitrite covering for the compressor blades.

And, working from the experience of Desert Storm and the early months in Iraq, they “double taped” the leading edges of their rotors to reduce wear from the sand, he said.

“That’s a maintenance workaround, rather than a real solution,” so they have started a “science program working with Sikorsky” to find a long-term cure, Dowling said. Sikorsky Aircraft Corp., Stratford, Conn., is a major manufacturer of military helicopters.

A key part of dealing with the older aircraft, Ernst said, is a recent shift to proactive maintenance, supported by a new focus on collecting and analyzing data on the effects of age and other factors on the condition of aircraft and their systems.

Today’s maintenance teams are urged to forecast incipient component failures and make changes to improve reliability and avoid an inopportune failure. The traditional practice was to inspect and repair or replace failed parts.

The services also have been developing better diagnostic systems to help monitor wear and anticipate failures.

As a result, the services have “a much better understanding of the health of our aircraft,” Stoll said. The emphasis is on “using analysis to try to solve problems, instead of just lamenting that we have an older fleet.”

One of Ernst’s priorities is to avoid conditions that occurred in the past, when older aircraft began to fail in flight and fliers died.

“We’re going to have that kind of situation over my dead body. … We are not going to let these aircraft be unsafe,” he declared.

Ernst acknowledged that “we are not always getting the funding” to make all the upgrades he would like, due to the severe competition for resources.

However, “I’m very confident that with the leadership we have today, and the systems in place, we are not going to have an unsafe condition.”
 
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