Weight Is Focus of Plane Safety[1]

By MATTHEW L. WALD

 WASHINGTON, Jan.27 - Saying that overloading may have contributed to a fatal plane crash this month in North Carolina, federal aviation officials announced today that thousands of passengers flying on small planes over the next month will have to tell ticket agents how much they weigh, or step on a scale, to check whether existing estimates of average passenger weight are accurate.

The Federal Aviation Administration is ordering all 24 airlines that operate the small planes to collect weight information from a sampling of their flights. Investigators suspect that a Beech 1900 that crashed on takeoff in Charlotte, N.C., on Jan. 8, killing all 21 people on board, was overloaded. Flawed weight estimates could have contributed. If studies show that average passenger weights have increased, that could require airlines to leave some passengers or baggage behind, especially on flights requiring full fuel loads.

Standard guidance from the agency to airlines flying small planes, including US Airways Express, which operated the Charlotte plane, is to allow 180 pounds for each adult in winter and 175 pounds in summer. Both figures include clothing and shoes and 20 pounds for carry-ons. Children ages 2 to 12 are assumed to weigh 80 pounds, year round.

These figures were developed before obesity became the public health problem it is today.

No recent studies have confirmed the current validity of the government's figures, said Lou Cusimano, deputy director for flight standards. "If we find the weights cannot be validated," he said, "we'll take the next step."

That would probably mean a bigger study that would weigh more people, he said. If the agency concludes that its averages are too low, it could raise the figures that airlines must use. The paperwork for the Charlotte plane showed it was within about 100 pounds of its maximum load, according to the National Transportation Safety Board, which is still investigating the accident. If passengers or their bags weighed more than assumed under the aviation administration's estimates, it may have been overweight. The plane's flight data recorder showed that it climbed at takeoff at an angle of 52 degrees before it crashed. It pitched up more and more steeply until it was pointed too high to fly. Investigators are looking into whether too much weight in the back of the plane caused the nose to pitch up.

The airlines will be adding 10 pounds to whatever passengers tell them that they weigh. Peggy Gilligan, director of flight standards at the agency, said that she expected people to fib about their weight, but that "they usually lie in the single digits." But officials said passengers generally do not consider the weight of their clothing and shoes. The airlines will also be weighing bags to verify that assumptions about their weight are still correct. The standard allowance is 25 pounds per bag for domestic flights and 30 pounds for international flights.

Aviation agency officials said they had been using the 180-pounds-per-person estimate since 1995 and possibly longer.

The rule issued today applies to 24 airlines that operate planes with 10 to 19 seats. There are 223 such planes in airline service, made by a number of manufacturers. The planes include the Beech 1900, the DeHavilland Twin Otter and the Embraer Bandeirante.

The airlines must ascertain the weight of all passengers and bags on a sampling of their flights, covering 30 percent of their routes. They must pick flights at varying times of day, and on a Sunday, a Monday and a Tuesday.

Mr. Cusimano of the aviation agency said that assumptions on weight were now used only for regular passenger service. If a small plane were being used as a charter for a football team or for a group of soldiers with heavy equipment, he said, the airline would have to weigh each bag and ask about the weight of each passenger.

Soon after the crash in Charlotte, investigators asked gate agents if there had been any "large-statured people" among the passengers, said John Goglia, the safety board member at the scene. Mr. Goglia said they had not, thus far, asked next-of-kin about the passengers' weights and would do so "only if concern got higher" in the overweight theory. Investigators tried to weigh the luggage, which was difficult because some of it had burned.

The plane was taking off in clear weather and a light wind for a scheduled 45-minute trip to the Greenville-Spartanburg airport in Greer, 84 miles to the southwest. It nosedived seconds after taking off, slamming into a maintenance hangar and bursting into flames. In another response to the Charlotte crash, the agency also ordered that all airlines flying Beech 1900's complete by Friday new inspections of the tail assembly to ensure that the elevators, the parts that control the nose-up or nose-down attitude, could move as far as they were supposed to.

The Beech in the Charlotte crash was serviced a few hours before the crash. Investigators suspect that the cables that run from the cockpit controls back to the tail were misrigged when they were reattached and that the elevators may not have been able to move as far into the nose-down position as they were designed to. The order to check the tail assemblies covers 368 Beech 1900's registered in the United States. There are 688 such planes in the worldwide fleet, including some in cargo use and some in corporate fleets.

Operators will now have to check the rigging after each time the tail is serviced, to ensure it moves properly.

The safety board can take more than a year to determine the cause of some plane accidents. Investigators in the Charlotte crash have said they are focusing on the cables that work the tail surfaces, the overall weight of the plane and whether too much of the weight was concentrated in the tail.

Officials at the aviation administration said that there was no direct evidence that the tail was misrigged and emphasized that it was not their agency but the safety board that would determine a cause. The safety board is an independent body, but the FAA. is one of the participants in its air crash investigations, along with the airline involved, the aircraft manufacturer, and other specialists, depending on the circumstances of each crash.