Airliner Dumps Fuel Over Lake Michigan

Officials are working to determine why an All Nippon Airways Boeing 777-300ER bound for Japan was forced to make a single-engine return approach to Chicago's O'Hare International Airport Monday morning... while residents expressed concern about the environmental impact from the fuel the heavy airliner was forced to dump over Lake Michigan.

Initial reports said the airliner (type shown above) may have suffered a bird strike on climbout from ORD, requiring the right engine to be shut down... but FAA spokeswoman Elizabeth Isham Cory told The Chicago Tribune the engine became inoperable due to unspecified "metal fatigue." The exact cause remains undetermined.

In order to land within weight limits, the airliner had to dump about 1,450 gallons -- or 4 percent -- of its fuel load over Lake Michigan, the nearest unpopulated area near Chicago... causing some concern from Chicago residents.

However, officials said only about two percent of the fuel probably reached the lake, since the fuel was dumped above 5,000 feet, allowing much of it to evaporate on the way down. That leaves about 32 gallons, all of it in small droplets, which will likely be broken down within a week by the combination of sunlight, wind, and hydrocarbon-hungry bacteria present in the lake.

April Markiewicz, associate director of the Institute of Environmental Toxicology at Western Washington University, told the Tribune those bacteria usually feed on naturally-occurring hydrocarbons, such as those found in discarded wood.

City officials will monitor the lake, to make sure none of the fuel makes it into the municipal water supply.

FMI: www.ohare.com, www.flyana.com