Should there be a retirement age for aircraft?

Critics say not enough scrutiny is given to wiring and other components in older jetliners. Others say it's not age that matters, but how well a jet

By BILL ADAIR

© St. Petersburg Times, published August 27, 2000

WASHINGTON -- When investigators from the National Transportation Safety Board found cracked wires in the wreckage of TWA Flight 800, they decided to look at other planes.

What they found dismayed them: wires with cracks and gouges. Some with burn marks from short-circuiting. Others stained from lavatory leaks.

There was a clear pattern: They found more problems in older planes.

Their findings have renewed the debate about whether an old plane is as safe as a new one.

Last week, the NTSB said the 1996 explosion of the TWA plane most likely was caused by a short circuit that ignited a fuel-air mixture in the Boeing 747's center fuel tank. The board said it could not directly link the explosion to old or poorly maintained wiring, but it called on the government to improve inspections of old wire.

NTSB Chairman Jim Hall said the aviation industry is not paying enough attention to aging aircraft issues.

"Most people understand that as you get older, things degrade," Hall said.

John Goglia, a safety board member and former USAir mechanic, said what matters is proper maintenance, not the age of a plane.

"A properly maintained airplane can last forever," Goglia said.

The debate about old airplanes has simmered since 1988, when an 18-foot fuselage section on an Aloha Airlines 737 peeled away in flight, killing a flight attendant. The accident, which was blamed on the airline's poor maintenance, led to widespread improvements in the inspections of older planes.

Despite those improvements, critics continue to say the airlines and the government are not doing enough.

Presidential candidate Ralph Nader recently called for mandatory retirement of older planes because he thinks they are not safe.

But statistics don't back up Nader's claim. The overwhelming majority of accidents are caused by human error.

In the past 20 years, there has been no correlation between crashes and aircraft age.

Indeed, mechanics say there actually are benefits from older planes because they discover the glitches over the years and fix them.

"Airplanes talk to you," said Tony Ristuccia, a New York aviation consultant who worked in TWA's maintenance department for 39 years. "If you understand what it's saying, you can find your problem and increase safety."

'Hard time'

With new paint jobs and modern interiors, it's hard to tell a plane's age when you climb on board. The inside of an old, refurbished plane looks pretty much like a new one.

A typical plane flown by the major airlines is about 11 years old, but the average is 16 years when all airlines are included.

Many airliners are more than 25 years old. TWA has 29 DC-9s with an average age of 31 years.

The average age for the entire U.S. fleet continues to get older. It was 12.7 years in 1988 and will be nearly 20 by 2007.

Airline pilots must retire at age 60, but the government has no retirement age for their planes.

As long as an aircraft meets federal standards, it can continue to fly. To comply, airlines must constantly inspect the planes and replace or refurbish key parts.

Take a 25-year-old plane, for example.

It's likely that the frame and fuselage skin are the originals, but most other components have probably been replaced at least once. Some equipment, such as landing gear and engines, has a "hard time" limit, which means it must be replaced or refurbished after a certain number of flights or a specific period of time.

Other parts are replaced when they malfunction or get worn out.

As a result of the refurbishment, many old planes flying today have been retrofitted with state-of-the-art gadgets.

Peek inside the cabin of a DC-9 and you'll see sophisticated computers that weren't invented when the plane came off the assembly line.

"Most older airplanes out there are in better condition than they were when they were delivered because we have been making continuous improvements," said Don Andersen, manager of wiring for Boeing.

Planes ultimately get retired, not because they become unsafe, but because they are too costly to maintain.

But despite the generally good track record of older planes, NTSB investigators said last week that they were concerned that aging wiring had not gotten sufficient attention.

Bernard S. Loeb, NTSB's director of aviation safety, said hazards such as cracked wiring "increase the potential for short circuits to occur."

He said maintenance procedures by the airlines "do not adequately protect aircraft electrical wiring, especially with regard to older airplanes."

Dissecting in the desert

In the desert of New Mexico, inspectors from the Federal Aviation Administration are dissecting dead planes.

Aircraft at the Sandia National Laboratories are being dismantled so inspectors can study the effects of aging and try new techniques to find hidden problems.

As they pick apart the cadavers of a 747, 727, a Lockheed L-1011, an Airbus A300 and two DC-9s, the inspectors have seen the same kinds of wiring hazards the NTSB did: chafed and cracked insulation and metal shavings that have piled up on wires. (The metal shavings pile up when mechanics drill a hole but don't clean up their mess.)

FAA inspectors have noticed a pattern in the old planes: Damaged wires are usually in areas where mechanics have done frequent work. Wires in areas that weren't accessible to mechanics are in pristine condition.

That illustrates the crucial issue with older planes: It's not the age of the plane that matters, it's how well it has been maintained.

Elizabeth Erickson, the FAA's director of aircraft certification, said the findings from Sandia indicate the need for better training of mechanics, so they will be more careful when they are working around wiring.

"We definitely need improvements in maintenance and design practices," Erickson said.

Erickson said that since the Aloha Airlines accident, the FAA's effort to beef up inspections of airplane structures -- the skin and bones of a plane -- has been highly successful. "We've not seen an aging-structure accident since then," she said.

Now, the FAA is focusing on problems with aging wiring, electrical devices and flight controls. Wiring will be the agency's top priority because the government and manufacturers have not had many requirements for regular inspections.

Examining airplane wiring isn't easy. A 747 contains 200 miles of wires, much of it in bundles that can't be seen by mechanics.

Researchers at Sandia are experimenting with new devices that might warn of a potential short circuit or detect damage that mechanics cannot see. The government also plans to make improvements to a manual that many mechanics say is confusing.

Last week, NTSB officials praised those efforts, but said the FAA needs to do more.

"I personally feel anything that is in an aging system needs more attention," said Hall, the NTSB chairman. "I don't feel the (FAA and the industry) have taken that into consideration."

Hall said the FAA should not become complacent because some planes have aged well.

Planes are like people, he said, and "anybody that has been to a high school reunion knows that people age at different rates."

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