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Airliner Autoland Stats

  1. May 8, 2006 #1


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    Staff: Mentor

    Does anyone have any stats on how often airliners land themselves? I googled a little and couldn't find any.
  2. jcsd
  3. May 8, 2006 #2
    I *think* they are requried to make 1 in 3 landings manually, but don't quote me.
  4. May 11, 2006 #3
    An Involved Question

    Hello Russ,

    The answer is much more complex than I am afraid you were hoping for. First, since I am new here, let me establish my credibility so you don't think I'm some yo-yo flapping my yapper. I am a commercial aircraft flight control design engineer who worked on MD-11 and B-717 autoland design and development, and I also worked for FedEx for 5 years as their CAT IIIb autoland engineering expert. So I am quite familiar with airline automatic landing programs and how the FAA certifies them operationally.

    Basically, there is no set FAA requirement for this, and not ALL aircraft are autoland capable. And even those aircraft that ARE autoland capable, not all airlines enact programs to utilize that capability. FedEx is big on its use since they have $-back guarantees if they don't get their packages to their destinations on time.

    All that being said: An airline must file an application with their FAA Principle Operations Inspector stating they wish to operate a certain make/model of aircraft for autoland operations. This application begins the process whereby the airline must now write-up a formal operations, maintenance and engineering program for how they will fly the airplanes, collect data on them, and maintain them to manufacturer's specifications for CAT IIIb (low weather minimums) compliance. As part of this application it is usually left to the operator to propose to the FAA how often each tail number has to do a "practice" (i.e. VFR) automatic landing.

    At FedEx, in order for an otherwise "healthy" autoland aircraft to remain available for dispatch into known CAT III weather, it would have to make a "practice" autoland every 30 days. But that is just the way FedEx structured their programs. It comes down to "use it or lose it". If you let a long time pass before you force all the redundant control systems to "play" in autoland mode, the chances of you experiencing a failure when you really need to use the autoland mode is higher. This is why we justified the "every 30 days" rule to keep an autoland airplane in a "CAT IIIb ready" state. In addition to this, airlines are required to keep accurate records of how many autoland attempts are made, and how many were successful, for each autoland aircraft they utilize. These stats are reported to their FAA POI usually on a monthly basis for their entire fleet.

    I hope this helps. Feel free to ask any follow-up questions.
  5. May 11, 2006 #4


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    Science Advisor

    So chances are that the info is spread out over many fleets but probably not assembled to the top level like Russ is looking for? I would think that ILS operations would have to log this kind of stuff in as well.
  6. May 11, 2006 #5


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    Gold Member

    Hey, guys;
    One of my pool buddies, an ex-bush pilot, e-mailed me this a couple of weeks ago. I posted it here because of the highlighted section.

    >> > After every flight, Quantas Australia pilots fill out a form, called a
    >>> > "gripesheet," which tells mechanics about problems with the aircraft.
    >>> > The mechanics correct the problems, document their repairs on the
    >>> > form,
    >>> > and then pilots review the gripe sheets before the next flight.
    >>> >
    >>> > Never let it be said that ground crews lack a sense of humor.
    >>> >
    >>> > Here are some actual maintenance complaints submitted by Qantas'
    >>> > pilots
    >>> > (marked with a P) and the solutions recorded (marked with an S) by
    >>> > maintenance engineers.
    >>> >
    >>> > By the way Qantas is the only major airline that has never, ever, had
    >>> > an
    >>> > accident.
    >>> >
    >>> > P: Left inside main tire almost needs replacement.
    >>> > S: Almost replaced left inside main tire.
    >>> >
    >>> > P: Test flight OK, except auto-land very rough.
    >>> > S: Auto-land not installed on this aircraft.

    >>> >
    >>> > P: Something loose in cockpit.
    >>> > S: Something tightened in cockpit.
    >>> >
    >>> > P: Dead bugs on windshield.
    >>> > S: Live bugs on back-order.
    >>> >
    >>> > P: Autopilot in altitude-hold mode produces a 200 feet per minute
    >>> > descent.
    >>> > S: Cannot reproduce problem on ground.
    >>> >
    >>> > P: Evidence of leak on right main landing gear.
    >>> > S: Evidence removed.
    >>> >
    >>> > P: DME volume unbelievably loud.
    >>> > S: DME volume set to more believable level.
    >>> >
    >>> > P: Friction locks cause throttle levers to stick.
    >>> > S: That's what friction locks are for.
    >>> >
    >>> > P: IFF inoperative in OFF mode.
    >>> > S: IFF always inoperative in OFF mode.
    >>> >
    >>> > P: Suspected crack in windshield.
    >>> > S: Suspect you're right.
    >>> >
    >>> > P: Number 3 engine missing.
    >>> > S: Engine found on right wing after brief search.
    >>> >
    >>> > P: Aircraft handles funny.
    >>> > S: Aircraft warned to straighten up, fly right, and be serious.
    >>> >
    >>> > P: Target radar hums.
    >>> > S: Reprogrammed target radar with lyrics.
    >>> >
    >>> > P: Mouse in cockpit.
    >>> > S: Cat installed.
    >>> >
    >>> > And the best one for last...........
    >>> >
    >>> > P: Noise coming from under instrument panel. Sounds like a midget
    >>> > pounding on something with a hammer.
    >>> > S: Took hammer away from midget
  7. May 11, 2006 #6
    Hi Fred,
    Roger that. If anyone were to assemble it at a top-level, it would have to be the FAA, specifically the AFS-410 office. They are both the policy setters for these kinds of special flight ops, as well as the national "policy police" for them. I know they often look at operator's CAT III ops data, so like I say they would be the door to knock on.

    I assume you mean on the aircraft side, and not the ILS ground station side. As far as I know, the only "required" place for an ILS approach to be logged (they can include manually-flown, of course) is in the pilot's own logbook. But on the ground side I don't believe there is a logging requirement for anything other that uptime or downtime of the transmitter and if it ever switches over from primary to backup channels.

  8. May 11, 2006 #7


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    Staff: Mentor

    Wow - welcome aboard. One nice thing about this board is somehow we get a lot of uncommon specialties here....

    Anyway, thanks for the info.
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