Is it OK to fix an airplane with tape?
Readers expressed a certain befuddlement after I claimed to know of only two major disasters related to the failure of a plane's tail -- the crash of American Flight 587 in 2001, which touched off the whole conversation, and that of the Japan Airlines 747 in 1985.
"Didn't the Boeing 737 suffer a legacy of tail problems?" posed a reader, "resulting in at least one serious crash?"
Two crashes, to be more accurate: that of a US Air -- as it was then called -- flight near Pittsburgh in 1994, and a United flight at Colorado Springs three years earlier. The result of these mishaps was a drawn-out controversy over the design of Boeing's rudder control unit, culminating in a 2002 FAA directive ordering a rudder control retrofit of the entire 737 fleet. (No small task. The 737 has been in service since 1968, and has become the most popular jet airliner. In 2004, according to Air Transport World, just under 4,000 examples, of nine different series, operate commercially around the globe.)
I omitted these crashes, and several other nonfatal incidents of rogue rudders, because they differ from the sorts of structural failures we were talking about, i.e. whole tails, or sections thereof, separating from the fuselage.
It remains a fundamental aerodynamic axiom, by the way, that a plane will not stay in the air without its tail. How much of its tail, however, varies from event to event. Take a look at this, from 1944. They don't build 'em like they used to, maybe. That's a B-29, the workhorse Boeing bomber immortalized for its special deliveries to Hiroshima and Nagasaki at the end of World War II. (Anybody remember the song "Enola Gay," by the synth band OMD, early 1980s?)
"But doesn't the breaking of the jackscrew on the tail of that Alaska Air MD-80 qualify as a 'tail disaster?'" asks Jennifer McGowan, writing from North Carolina. She's referring to the February 2000 crash of Alaska Airlines Flight 261 that killed 88 passengers and crew.
Yes and no; mostly no. The jackscrew unit was in the horizontal stabilizer -- the small pair of aft-mounted wings that maintain stability around a plane's lateral axis, and to which the elevators (for nose-up/nose-down "pitch" control) are attached. In the case of the MD-80 -- and assorted others, from the 727 to the Tu-154 -- this assembly happens to sit atop the tail, but is not, strictly speaking, part of the tail itself.
When the jackscrew failed, Alaska 261 lost control of its horizontal stabilizers -- specifically their "trim" function, which fine-tunes the forces of pitch -- not its rudder, and there was no in-flight breakup. Thus, while I hate to nit-pick -- which is to say I love to nit-pick -- what happened in the Alaska Airlines tragedy was not a "tail" tragedy in the sense of American or JAL.
While we're at it, McGowan obviously never saw my column from about a year ago, the profoundly moving treatise wherein I petulantly address the more egregious misspellings of airline names. There is no such thing as "Alaska Air." Not to be outdone, another reader submits: "I seem to remember an Air Alaska aircraft that crashed due to a failure of a jackscrew in the tail."
What's wrong with you people? And why do you suppose the editors at Penguin snipped that particular lesson from my book?
Speaking of which, applause to Lisa Wixon of New York City, for accurately deciphering last week's stolen simile riddle. "A miracle on the order of the loaves and fishes," was the quote, appropriated from Kurt Vonnegut Jr. It appears in the introduction to Vonnegut's early short story collection, "Welcome to the Monkey House," published the same year the 737 debuted.
"Monkey House" is neither Vonnegut's best book (that'd be "Slaughterhouse Five"), nor the funniest one ("Deadeye Dick" or "Jailbird"), but the loaves and fishes line always stayed with me. Like so many of his sentences, it has that sort of ticklish profundity. Vonnegut was once kind enough to provide me with an autographed self-portrait.
Asked once in an interview how he'd most prefer to die, Vonnegut responded, "In a plane crash on Mount Kilimanjaro." The weirdly captivating romance, for lack of a better term, of such a death is grist for a future column, but Vonnegut seems to understand. If for no other reason than that, he became my favorite author.
Not that you asked, but the funniest books not written by Kurt Vonnegut Jr. are Spalding Gray's "Sex and Death to the Age Fourteen" and, if you're looking for something truly and darkly hilarious, "Cold Dog Soup" by the novelist and poet Stephen Dobyns. I'm known to lift a Dobyns line here and there also.
But I digress.
According to a new study by the Centers for Disease Control, the average weight of Americans increased 10 pounds in the 1990s. Heavier fliers, says the report, require planes to burn more fuel, which in turn drives up fares. I find it hard to believe that the theoretical extra ton or two from chubby butts would seriously change fuel consumption. Am I wrong?
More weight means more fuel; there's no way around it. Two hundred passengers on a given flight, at an extra 10 pounds each, means 2,000 added pounds. Specifically, the CDC states that in the year 2000, U.S. airlines had to burn 350 million extra gallons of fuel, at a cost of more than a quarter of a billion dollars, to haul the added weight of ever-widening Americans. That extra fuel released an estimated 3.8 million tons of climate-changing carbon dioxide into the atmosphere.
Those are, if I may, pretty fat numbers, but they deserve some perspective. In the case of a fully loaded 747, which has a maximum takeoff weight close to 900,000 pounds, the sum heft of an overbooked cabin (about 400 well-fed souls) represents less than 10 percent of the total, which mostly consists of fuel (about 400,000 pounds), freight and the vessel itself.
That ratio isn't so impressive with every model, as the 747 has outrageous economies of scale. Generally, the smaller the aircraft, the more your girth matters. With the 747, our extra 10 pounds equate to .046 of the maximum. In the case of a 19-seater, it's about 1.2 percent.
That's not to downplay the significance of those 350 million extra gallons; only to point out that the weight of the passengers may not be as crucial to overall efficiency as you think. A less than optimal cruising altitude, for instance, can burn a lot more fuel than the expanded waistlines of those on board.
But for good measure, at least in this country, the airlines have turned proactive by refusing to feed you.
As for "driving up fares," while the impetus is there in concept, fares remain cheaper than ever. Mean ticket prices in today's dollars are the cheapest they've been since 1987. Adjusted for inflation, they are the lowest ever.
Please tell me the following photograph, sent to me by a friend who swears he took the picture himself, is doctored.
I'm willing to bet the picture is not doctored. What you see is the perfectly safe and legal application of some heavy-duty aluminum bonding tape, called "speed tape" in the mechanic's lexicon. Depending on what a plane's maintenance manual stipulates -- according to the dictates of the FAA -- certain noncritical components can be temporarily patched with this material, embarrassing as it sometimes looks. It's extremely strong, durable, and able to expand and contract through an extreme range of temperatures.
Here you see speed tape covering a crack or some other superficial defect in a flap track fairing. That bullet-shaped fairing is just a cover, a streamlining shell, that conceals the tracks and hinges of the wing's trailing edge flaps.
I have a colleague who says that when taking off from Long Beach Airport, the plane crosses over a section of the city which, because of anti-noise rules, requires the pilot to shut off the engines, and then restart them. She said the pilot gets on the loudspeaker before flight to notify the passengers.
And I have a colleague who insists that the planet Earth is only 5,000 years old, that the pope is an operative of Satan, and that a shady cabal of Zionist conspirators, in league with the United Nations, controls my neighborhood bank and the New York Times. I really hate to say it, but guess which colleague has the more credible argument?
Don't take it personally, yours is one of hundreds of implausible scenarios presented by anxious or otherwise ill-informed flyers.
Noise abatement strictures are quite common when taking off over urban neighborhoods. They might dictate a steeper than normal ascent; unusually close-in turns, and/or a reduced thrust setting during climb-out. But reducing power and switching the engines off are completely different things. No commercial aircrew, ever, intentionally shuts down an engine for any reason short of a serious problem or emergency.
With regard to your second-hand story, it's possible the crew informed passengers of a noise abatement maneuver so they would not be alarmed by a power reduction soon after liftoff. Even this is strange, however, as the changes in sound and acceleration aren't normally very drastic.
Airplanes take off and land into the wind whenever they can, but noise restrictions are one of the factors that occasionally make this impossible. Some runways, indeed whole airports, are subject to nighttime curfews.
About the writer
Patrick Smith is an airline pilo
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Nov. 19, 2004
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