WASHINGTON - Air travel would be safer if airlines weighed their passengers from time to time to make sure they know how much weight their planes are carrying, the National Transportation Safety Board says.
After its investigation into a commuter plane crash last year in North Carolina, the NTSB said Thursday that airlines should at least periodically make passengers step on a scale.
The safety board also recommended the Federal Aviation Administration require improvements to training, oversight and procedures for maintenance personnel.
The crash of US Airways Express Flight 5481 at Charlotte-Douglas Airport killed 21 people, the deadliest U.S. aviation accident in nearly 212 years.
The Beech 1900, operated by Air Midwest, was virtually uncontrollable because of two fatal mistakes, the safety board concluded.
First, the airline's guidelines for estimating the weight of passengers and baggage were inaccurate. The pilots, therefore, didn't realize the plane's rear section was too heavy.
Second, mechanics had improperly rigged cables connected to the elevator, the tail flap that controls the up-and-down direction of the aircraft's nose. The errors meant the elevator's downward motion was restricted to half its normal range, according to the NTSB.
Without a fully maneuverable elevator, the pilots couldn't force the nose of the plane down to compensate for its heavy tail, investigators said.
As a result, the plane pitched sharply upward just seconds after takeoff for Greer, S.C., then fell from the sky.
Soon afterward, the FAA ordered airlines to weigh some of their passengers to determine the accuracy of current guidelines - for example, adults in winter were calculated to weigh 185 pounds on average.
The survey showed what many suspected: Passengers and their bags had gotten heavier. The FAA issued temporary guidelines adding as much as 10 pounds to its estimate for passengers and 5 pounds to checked luggage.
The NTSB said those guidelines don't go far enough. The board recommended that the FAA require airlines operating planes with 10 or more seats to weigh passengers periodically to determine when they might be heavier.
The FAA is working on that. Since June, a committee has been examining the average weights of passengers and baggage and how they vary according to season or geography.