The Americans carried out experiments on a circular runway back in the late 1940s. They used a circular automobile test track which, I think, was somewhere near Detroit. DC-3s flew from it and also a DC-4 I believe.
Of course, this solved all sorts of problems but generated just as many others.
I have a vague recollection that the final stopper was the high side loads operating on the undercarriage.
Whoa.....talk about thread drift. Get back to the topic at hand shall we. Anyone with any ideas as to what the Dfdr says wrt the 767 landing. Taken it was hard ..
我々日本人 (We Japanese) pilots are the safest in the world. We are まじめ、(honest and diligent). You 外人 (foreign) pilots are all cowboys. Wearing white deerskin gloves is very important, maybe as much as as is our ANA procedure. This incident is Boeing's fault .
People keep assuming the pilots push forward after the bounce. I am not so sure this is the case. I was once on the jumpseat for a very heavy landing into Heraklion (though no airframe damage) and there was a very pronounced nose down moment after the initial touchdown. The handling pilot swore he did not put in a nose down input (not did he flare, but that is another issue) and later we figured it to be the following:
Big bounce on main wheels --> main wheels are behind the CG --> a nose down moment as a result.
Not to say it will happen like that every time, many factors I am sure can influence it, but I would not automatically assume that so many pilots push forward on the yoke after a heavy landing.
I'd like to give them the benefit of the doubt but a replay of the video shows more of a 'skip' than a 'bounce'.
Quote:
I was once on the jumpseat for a very heavy landing into Heraklion (though no airframe damage) and there was a very pronounced nose down moment after the initial touchdown. The handling pilot swore he did not put in a nose down input (nor did he flare, but that is another issue)
If he didn't flare, then the elevator would have been in a fairly neutral position, which would have led to the nose dropping rapidly after T/D. Also, the oleo travel was probably taken up pretty quickly, leading to the undercarriage/airframe combo acting as a rigid object from an inertial point-of-view.
Having worked in Japan for several years I can tell you that ANA pilots are the worst. Unable to think outside the box, inflexible, lack of common sense, etc. I avoid Japanese carriers all the time. Too many incidents with ANA lately. The 737 upset, the AJX 767 that flew through the thunderstorm on approach to NRT a couple months ago that was hit by lightening, several tailstrikes, all the ANA planes that land during typhoons while all the other carriers divert, and many more. Must be something in their culture.
I agree with Fullwings. The aircraft was airborne again when the nose went down. That didn't happen because of the C of G. Fair enough, if you just smacked it on, that the nose may then also smack on shortly after because of the C of G position, but in this case, the aircraft went flying again before touching down the second time nose-first.
Last edited by Capn Bloggs; 1st Jul 2012 at 14:46.
Reason: spelin'
For what its worth, it was an autoland attempt. The airplane experienced a massive tailwind gust just before minimums and pitched down to pick up profile. The A/P was disconnected below minimums to pitch back up for the flare and was too late. Rest all on video. Of course this is just what the lil birdie tells me...
Decent flare there. High autobrake setting could have contributed to the high rate of derotation after mains touched down resulting in the high(and double!) nosewheel impact. Just my thoughts here..
Last edited by King on a Wing; 1st Jul 2012 at 11:45.
High autobrake setting could have contributed to the high rate of derotation after mains touched down resulting in the high(and double!) nosewheel impact. Just my thoughts here..
Well,did you ever fly an aircraft with autobrakes?
"Stunning first post Ricejet. You appear to know a lot when you actually know nothing."
I think 6 years flying at AJX, living in Japan, being Japanese, gives me a fairly good insight. Whats stunning is thinking you can evaluate someone's knowledge, or lack thereof, from a single post.
For what its worth, it was an autoland attempt. The airplane experienced a massive tailwind gust just before minimums and pitched down to pick up profile. The A/P was disconnected below minimums to pitch back up for the flare and was too late. Rest all on video. Of course this is just what the lil birdie tells me...
That sounds like an over-reliance on automation or late transition to the level of automation appropriate for the conditions.
Ricejet: "Having worked in Japan for several years I can tell you that ANA pilots are the worst. Unable to think outside the box, inflexible, lack of common sense, etc. I avoid Japanese carriers all the time. Too many incidents with ANA lately. The 737 upset, the AJX 767 that flew through the thunderstorm on approach to NRT a couple months ago that was hit by lightening, several tailstrikes, all the ANA planes that land during typhoons while all the other carriers divert, and many more. Must be something in their culture."
I don't agree. I have worked with Japanese high tech companies for more than 10 years, and have spent much time in meeting rooms and labs with my Japanese colleagues. While the outcome in terms of development results and delivery performance has always been admirable in the long run, getting there was hard work and sometimes frustrating. I have experienced many instances where the Japanese team had in our eyes simply forgotten all common sense, where the team would happily stampede into the wrong direction, where things were neglected that a second year engineering student would consider basics, where production and quality control procedures were installed that had no fail-safing (poka yoke) whatsoever and no failure mode analyses were carried out.
Reading about nuclear accident investigations in Japan paints a similar picture of inflexibility, group-think, naivite, over-reliance on automation and the inability to imagine that things sometimes do not go as planned.
If these kind of cultural issues were also prevalent in the airline industry, you'd expect planes to be dropping out of the skies like those of some other Asian airlines in the 80s and 90s. But when you look at statistics, Japanese airlines have been really remarkably safe since the early 70s, and even more so after JAL123 where Boeing and JAL maintenance shared the blame. The picture remains the same when you look at glitches that could have ended a lot worse. Admittedly, there were some maintenance issues at JAL a few years ago, and the ANA 737 upset raised and the recent spate of tail scrapes at JAL and ANA raised some eyebrows, but the overall frequency of such glitches does not appear to be higher than in other airlines that have a strong safety culture and excellent track record (CO, DL, BA, LH to name a few).
I don't know what they do differently than the rest of the technical community in Japan, but I'd sure like to know.
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