American Culture

Is Flight 447 destined to be remembered like Flight 800?

Two pieces of evidence have emerged that lend new credence to the theory that the Air France jet that crashed more than a week ago broke up in flight.

. . . reports the New York Times today.

And Airbus, the plane’s manufacturer, sent its airline customers a bulletin saying . . . the parts that measure air speed may have failed first.

A faulty air speed indicator could mislead pilots into flying faster than the aircraft could withstand, or faster than it should be flown into turbulence — two circumstances that could lead to the craft coming apart in flight.

No pilots are more insulated from the operation of their aircraft than those flying Airbus with its “fly-by-wire” electronic system that provides for no manual or hydraulic. Still, you’d think the pilots, with their years of experience, could sense if they were going too fast, especially into a storm.

Unless pilots can confirm that this scenario seems plausible, Flight 447 will be filed with another infamous crash in the memory banks of skeptics everywhere. If you’ll recall, TWA Flight 800 is thought by many to have been shot down by a surface-to-air missile off Long Island, New York in 1996. And, as you’re probably heard by now, Air France received a bomb threat (which didn’t pan out) on a South America to Paris flight just four days before Flight 447 crashed.

7 replies »

  1. Russ,

    I’ve flown on many jumpseats in many cockpits during my years with an air cargo carrier. I have no idea in the world how a pilot would know airspeed without a valid reading from an airspeed indicator. I mean, even over land, you’re so far up that it would take an enormous change in speed to create a noticeable change in how fast the land is scrolling under you, and even that would be only land speed and would be interpreted as due to a tailwind, I suspect.

    How you would judge airspeed by the seat of your pants is even more problematic when flying over water and/or at night.

    I have no idea what happened to that aircraft, but I would be very interested to hear from pilots if they could judge airspeed over water by the seat of their pants if their instruments are wrong. At this juncture, I doubt it.

  2. Russ:

    Still hoping some pilots will chime in, but I did think of one thing (as a rank amateur who has only flown in cockpits) that might be a very rough cockpit indicator of airspeed: the throttles (assuming this aircraft had manual throttle controls). In calm air, throttles pushed too far forward might indicate that the plane was being pushed too hard through the air, I suppose. The problem is that turbulent conditions create sudden shifts in wind speed and direction, so throttle position would be very poor indicator of that. The pilots would probably keep an eye on air speed and adjust the throttles accordingly.

    Just a guess, and not a terribly well-informed one.

  3. Thanks, JSO. If I get a moment, I’ll go to a pilot’s forum or message board to learn what they think.

  4. Here’s the latest from the Christian Science Monitor about the possibility of terrorism:

    a Spanish pilot flying in the same area reported he saw a “bright white flash” in the sky that evening. That could indicate a midair explosion of some kind. … And now, there are the reports that the passengers included two people whose names match those on France’s terrorist watch list.

    But terrorism experts warn against jumping to any conclusions.

    “Terrorist watch lists are notoriously unreliable.”

  5. Yeah, Russ, I saw that, but I also saw something that said the bright white flash could easily have been lightning, and I also saw a quote from a bomb expert who said bright white flashes don’t really fit most types of material that would make a bomb, and that a bomb of any size wouldn’t have produced the (so far) known behavior of the aircraft — only a small bomb that led to depressurization could have done that.

    As for the terrorist angle, I currently think it’s low probability. The whole point of terrorism is to scare people, so a terrorist act done in secret seems downright stupid. All prior aircraft I can think of that were brought down by terrorist acts were sabotaged where the sabotage could be seen, even if no one claimed responsibility.

    Barring further revelations, it appears to me from published reports that the most likely explanation is pilot error, mechanical error, or a combination of both. I hope there is enough data to find out for sure.

  6. One way to tell speed is by the sound. Cockpits are noisy and the hissing sound increases with speed in a jet.

    The speed can be judged reasonably well if it going to slow (easier to judge) or too fast a bit harder. Feedback (even if artificial) is another reference. Just the loss of airspeed indication won’t be a major problem at all except possibly if on autopilot, but combined with other references can be of course. Likely whatever might cause airspeed problems would be causing other issues also.

    The main loss would be attitude references. (nose and wing position in relation to the horizon) With no visual references to compensate for loss of attitude instrument(s) it is only a matter of time before the aircraft is “upset”, and likely something is going to break fairly soon… engine snaps off, tail or wing.

    A similar accident was a Swissair flight that had major electrical fault a few years, back over the Atlantic, at night. Control was lost when an attempt was made to get back to Halifax because of no instrument or outside visual references.

    There is a rather simple fix for these all electric contraptions flying around today, and perhaps there is. I know my first days in a jet, around 1970, there was a set of the old fashioned instruments in case the fancy computer driven instruments acted up. You got the basic information you needed. I don’t know if that is done anymore. Have to see an Airbus cockpit to tell.

    James – ATPL