• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

AA Checks Faulty MD80 Fuel Gauges

Posted on: Tuesday, 21 February 2006, 12:00 CST

By Staff and Wire Reports

The problem likely stems from microbes growing in water in the fuel.

American Airlines is inspecting the fuel systems on about half its planes after pilots said fuel gauges were not working.

The problem, found on some of the airline's Boeing Co. MD80 aircraft, is probably caused by microbes growing in water in the fuel, American spokesman John Hotard said Friday. The microbes are attaching to sensors that measure fuel level, he said.

Aircraft mechanics at American's Maintenance & Engineering Center in Tulsa are examining the fuel tanks and the fuel sensors, Hotard said. The MD80s receive major overhauls, or C checks, at the Tulsa base, the largest aircraft maintenance, repair and overhaul facility in the world.

"The (major) work is being done in Tulsa, where they're looking at the tanks, replacing the fuel probes if necessary," Hotard said. "Draining the water pumps in the wing (tanks) at night is done at the larger maintenance stations overnight. By far the largest amount of work by engineers, managers and employees is being done in Tulsa."

American is the largest operator of MD80s, with 327, and the planes make up 47 percent of its fleet. The problem isn't limited to American, said Alison Duquette, a Federal Aviation Adminis tration spokeswoman.

"We've been aware of the issue for several months and have been working with American to resolve it," said Duquette, who was unable to name other carriers that had reported the same problem. The FAA is trying to determine if the problem extends to other aircraft types, she said.

American flew 491,528 MD80 flights in 2005, and there were 50 instances in which MD80 fuel gauges were found to be inaccurate. Of those, three were found to be related to other issues. The airline did not provide comparable numbers for 2006 flights.

Alaska Air Group Inc., which flies MD80s, declined to comment. Delta Air Lines Inc. said nothing unusual had been reported involving fuel sensors on its MD88 and MD90 aircraft.

The affected gauges usually are off by 200 to 300 pounds of fuel, well below the 4,000- to 4,500-pound reserve carried by the planes, Hotard said.

"The bottom line is, these are safe aircraft flying around out there," he said in an interview.

American is trying to fix the problem by draining the pumps used to remove water from the fuel more often, and using a biocide to kill the microbes, Hotard said.

Water is present in jet-fuel tanks because repeated heating and cooling causes condensation. It normally does not affect a plane's operation, he said.

The problem began shortly after hurricanes hit the Gulf Coast in September and disrupted fuel supplies from refineries. There has been speculation that added water might have gotten into the fuel from flooding near pipelines. The problem probably would not be limited to MD80s if that were the case, Hotard said.

American also is testing fuel supplies at various U.S. airports and trying to determine if the age of the MD80s has any correlation to the problem. American's MD80 fleet has an average age of 16 years.

Boeing gives carriers guidance in manuals for getting the microbes out of the tanks, said Liz Verdier, a company spokeswoman.

"This isn't an unusual problem," she said. "Bugs in the fuel have been around a very long time."

Gregg Overman, a spokesman for the Allied Pilots Association, said the union's members are aware of the problem.

"We're quite comfortable with the response the airline has taken," he said. "It's just one of those things you want to be very careful about."

This story was written by Mary Schlangenstein of Bloomberg News, with contributions from the Tulsa World business staff.

Source: Tulsa World

More News in this Category