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Air France 447 - Interesting article

Old 09-05-2017, 02:54 AM
  #41  
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Originally Posted by C130driver View Post
...When the aircraft is in a stall, you don't yank back on the yoke/stick.
When the aircraft is near its max altitude and the autopilot unexpectedly trips off, you don't yank back either. You might stall.
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Old 09-05-2017, 04:38 AM
  #42  
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Originally Posted by Adlerdriver View Post
Full, deep stall like these guys were in? Buffet, nose hunting, nose up attitude, low airspeed and most important of all, a high, high sink rate.
Describe what the buffet might feels like, please?
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Old 09-05-2017, 05:34 AM
  #43  
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Originally Posted by ptarmigan View Post
Describe what the buffet might feels like, please?
A heavy, moderate to high-frequency buffet, unlike anything else you would experience in flying.

Those who have flown high-performance military aircraft would know exactly what it feels like.
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Old 09-05-2017, 07:32 AM
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Originally Posted by UAL T38 Phlyer View Post
A heavy, moderate to high-frequency buffet, unlike anything else you would experience in flying.

Those who have flown high-performance military aircraft would know exactly what it feels like.
Maybe, maybe not. What the wing experiences is fairly close to the pilot experience in a fairly rigid tactical airplane. Big airplanes are different as you have a harmonic frequency for the fuselage that has its own mode. For example, on the A330 you would actually see +/- up to 2.0 g at a frequency of 2-4hz. Not like a stall in any tactical airplane. This is coupled around a baseline of 0.5 g due to the descent, of course. There is also an induced lateral mode, figure +/- 0.6g,so you have a combination far outside most pilots experience.
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Old 09-05-2017, 07:41 AM
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While the details vary with a larger, less rigid structure, there is no mistaking high AoA buffet in a wing with high wing loading.
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Old 09-05-2017, 08:08 AM
  #46  
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Originally Posted by UAL T38 Phlyer View Post
While the details vary with a larger, less rigid structure, there is no mistaking high AoA buffet in a wing with high wing loading.
If you've never experienced it, are not expecting it, and in turbulence, I think you are utilizing a fair bit of hindsight bias here!
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Old 09-05-2017, 09:41 AM
  #47  
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Originally Posted by Adlerdriver View Post
One of the basic tenants of aircraft operation is the use of known pitch and power settings. Pitot static malfunctions can create confusion but only if they are viewed as a singular event with no knowledge of events leading to them. An aircraft in level flight holding a stable airspeed at FL350 doesn't just start to overspeed or stall spontaneously.

Heart of the matter as far as I can tell. Perished not a clue as to why.
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Old 09-05-2017, 12:50 PM
  #48  
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Originally Posted by ptarmigan View Post
If you've never experienced it, are not expecting it, and in turbulence, I think you are utilizing a fair bit of hindsight bias here!
You're biased too, writing off every other pilot input on this accident. They messed up bad. They correctly identified the problem "we have bad speed indications" and then didn't follow procedure for it. After yanking back and stalling, all the FO in the right seat did was pitch for the Flight Director bars. That's fact, and shown in the accident animation created by the investigators. You seem to ignore all that, and make some argument for how the Gs and buffer they felt apparently threw them off too much to know they were stalled.
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Old 09-05-2017, 02:42 PM
  #49  
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Originally Posted by ShyGuy View Post
You're biased too, writing off every other pilot input on this accident. They messed up bad. They correctly identified the problem "we have bad speed indications" and then didn't follow procedure for it. After yanking back and stalling, all the FO in the right seat did was pitch for the Flight Director bars. That's fact, and shown in the accident animation created by the investigators. You seem to ignore all that, and make some argument for how the Gs and buffer they felt apparently threw them off too much to know they were stalled.
A video does not show sensations and the report, while good, missed many aspects that explain why they did what they did. I realize it makes us feel good to think we would not have done that, but sadly if you believe that, we have done nothing to prevent a repeat aside from install better pitots. Sad.
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Old 09-05-2017, 03:02 PM
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I'm sorry to be harsh. I've been flying bit airplanes for over 30 years, as well as investigating accidents. I have participated in evaluating aircraft performance, human performance, operations and numerous other factors. I have been a check airman and instructor on several types of large transport airplanes, worked in both management and in ALPA positions. I have spent the past 20 years also working on handling quality issues and researching based on the most recent understandings of human factors, including control feedback theory and cognitive factors.

I used to be like many of the respondents in this thread. I have learned better. We are all too quick to blame our fellow pilots as being weak. We also, in conjunction, believe that humans are the "weak point" in aviation safety, and also like to tell laypeople that "flying is easy". Then we are shocked when people tell us we're overpaid and not necessary.

The evidence, on the contrary, is overwhelming, that pilots are what keep flying safe, but we are now encountering areas for which we are not training pilots. That needs to be fixed. I have presented several examples here, and there are a lot more. We have not fixed exposure to microbursts really (although we are somewhat protected by MIT's LL algorithm at 67 U.S. airports and HKG), as a quick additional example.
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