Posted on 05/12/2003 7:40:31 PM PDT by Archangelsk
May 13, 2003
Estimated Passenger Weight Raised in Air Safety Effort
By MATTHEW L. WALD
WASHINGTON, May 12 — The Federal Aviation Administration today ordered airlines that fly planes with more than 19 seats to raise the assumed average weight of each passenger by 10 pounds and the assumed weight for each checked bag by an additional 5 to ensure that their planes are not overloaded.
The notice, which was sent to all airlines, gave them 90 days to adopt the new weight rules or to conduct their own surveys of passenger and luggage weight. The actions were prompted by the January crash of a US Airways commuter plane in North Carolina that may have been within current weight limits but may still have been overloaded. The National Transportation Safety Board is set to open hearings into that crash next week.
Since 1995, most airlines have assumed a weight of 180 pounds for each adult passenger in summer and 185 pounds in winter; checked bags are assumed to weigh 25 pounds each.
Some airlines that fly small planes with 19 or fewer seats have already raised their weight allowances by about 30 pounds, the F.A.A. said today. That followed an order from the agency earlier this year to 15 airlines asking them to survey passengers and bags and adjust their weight assumptions accordingly.
Some industry experts said the new weight requirements would mean that on some flights, mostly on smaller planes, cargo might have to be left behind or some seats unsold.
"It's going to have an impact," said Diane Spitaliere, a spokeswoman for the agency.
The order today is interim until the agency can set up a committee of private and government experts to study the issue further, an effort that is expected to take months or years.
Because the weight issue involves safety, no airline publicly disputed the agency's action, though some executives said closer surveys of actual weights might demonstrate that the new allowances were too high. Executives at several airlines said they had not yet seen the text of the order and so declined to make specific comments about it.
Even so, Ginger Hardage, a spokeswoman for Southwest Airlines, said such a change would most likely have an effect in the summer, when flights have more passengers and temperatures are higher. In hot weather, the air at ground level is thinner and a plane requires a longer runway to get airborne.
That could making runway length a limiting factor in some cases.
"There could be situations when we have to re-evaluate the number of people who are able to go on that aircraft," Ms. Hardage said.
Lisa Bailey, a spokeswoman for American Eagle, the commuter affiliate of American Airlines, said her airline already weighed bags individually on some flights from Kennedy International Airport, Miami and San Juan, P.R., because the actual weights were less than the old assumed weight, 25 pounds.
Ms. Bailey said she did not know what her airline would do when the assumed weight was raised to 30 pounds. The airline does not weigh its passengers, she said.
At US Airways, David Castelveter, a spokesman, said, "clearly there will be some impact on revenue, either from the passenger side or the cargo side, not on every flight every day, but in some circumstances." In places like Phoenix, Mr. Castelveter said, airlines already have to leave cargo or passengers behind on the hottest days. The new weight rules would just add to the number of days when that happened, he said.
The calculation of maximum weight is already done separately for each flight by airline dispatchers, who note the prevailing winds and calculate how much fuel a plane must carry to reach its destination; circle in a holding pattern there; and divert to another airport if necessary. On long flights the weight of the fuel can limit the plane's ability to carry passengers and cargo.
The order today modifies an F.A.A. system that set requirements for the "weight and balance" program that each airline must maintain. The airlines can either weigh each bag and ascertain the weight of each passenger (by asking, or by having the passenger step on a scale), or make an estimate about average passenger and bag weight.
Only airlines flying small planes weigh each passenger; Ms. Spitaliere said that probably few big airlines would do so.
"It's not going to make your customer very happy," she said.
Airline executives also said that weighing passengers would be cumbersome. Many passengers check in at machines, and weighing them would require more ticket agents.
Formally, the F.A.A. said today that it was adding 10 pounds for "personal items," which Ms. Spitaliere said included "coats, laptops, cameras, diaper bags, briefcases, purses, those kinds of things." But she added, "It's really 10 pounds per person."
And the F.A.A. added five pounds for each checked bag on domestic flights. International flights are covered by separate regulations.
Ms. Spitaliere said the airlines conducted surveys after the January crash and some found that passengers — once clothing and personal items were factored in — weighed an average of 20.63 pounds more than assumed; carry-on baggage weighed 5.72 extra pounds; and checked bags, 3.81 pounds, a total of 30.16 pounds than the assumed average.
The weight of checked bags is a separate issue on small planes, where the cargo hold is often behind the passengers, not below them, and thus not only affects the total weight of the plane but also the center of gravity. If the center of gravity is too far back, the pilots may be unable to control the plane's pitch. This may be what happened in Charlotte, N.C., combined with a problem in the pitch-control system.
As the F.A.A. acted, the safety board was preparing for hearings next Tuesday on the crash of that plane, a 19-seater, US Airways Express 5481, shortly after takeoff from Charlotte-Douglas International Airport, in North Carolina, on Jan. 8.
Today the F.A.A. played the air traffic control audio tape from that crash, in which the plane, possibly overloaded and possibly tail-heavy, pitched up at takeoff and became uncontrollable, the nose rising higher and higher. The problem came on so suddenly that the captain had time to radio just 10 words and in such a rush that she appeared to get her flight number wrong.
In the tape played today, the captain, Katie Leslie, 25, had time to say, "We have an emergency for Air Midwest 5480," in a voice that sounded shrill but not panicked. Until that point, communications on the fight, flying as US Airways Express 5481, had been handled by the first officer, or second-in-command, Jonathan Gibbs, including a routine acknowledgement that it had been cleared for takeoff. In normal practice, that would indicate the captain was flying the airplane and would not ordinarily touch the radios.
But a little less than a minute after Mr. Gibbs acknowledged the takeoff clearance, which would be about the time that the airplane began its roll down the runway, the plane's nose lifted and kept rising uncontrollably, and Captain Leslie blurted out the emergency.
The nose eventually reached a neck-straining 52 degrees. The plane, a Beech 1900 turboprop, was airborne only about 37 seconds, reaching an altitude of 1,200 feet, according to the National Transportation Safety Board, before plunging into the side of a hangar by the runway, killing both crew members and all 19 passengers aboard.
The remainder of the tape is a combination of routine communications between controllers and other airplanes, and a few bizarre moments. For example, another US Airways flight, inbound from Allentown, Pa., and turning to make its final approach, acknowledged that it had been cleared to land and then asked, "is that fire the fire department practicing?"
In the tower, the controller in charge of arrivals responded, "umm, we'll talk about it later."
Beneath the tower, a second controller, in charge of departures once planes cleared the runway, was apparently confused because the tower controller had sent him a "flight strip" — a computer-generated slip of paper giving the flight number, route, type of equipment and other details — but he could not find the plane on his radar scope.
"Local," said the controller, referring to his colleague in the control tower just above him, "I got an Air Midwest 5481 strip down here."
The local controller responded, "aah, just hold him."
"O.K., I'll hold it," said the departure controller.
"All right, that's the one that," said the tower controller, and then paused, "had a problem."
In the background was a sound like a car alarm; it was the crashed plane's Emergency Locator Transmitter, broadcasting a signal picked up in the tower.
Even though the CG may have been out of limits for the Beech, I believe that the extreme pitch was an indicator of an elevator going wildly out of control.
You'd have to ask the engineers. They've developed sensors for just about everything else. It may need to combine main gear and nose gear, but I don't know whether it's practical or not.
Use three sensors, one for each side and one for the nose. Then the plane would not only have a measurement of its weight, but equally if not more important its center of mass.
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