National Airlines B747-400 Freighter (BCF) Down in Bagram, Afghanistan

Okay, some here have speculated that the load-shift may have occurred at rotation. Here are some (hopefully not stupid) questions:

How obvious is a load-shift if you feel it during your take-off roll? Would it even happen on take-off roll simply due to the acceleration?

When the load-shift occurs, even at rotation, are you better off simply closing the throttles and taking your chances with whatever is in front of you? Is there simply not enough time to process the information AT rotation and by the time you know you're already several hundred feet?

Guess I'm looking for anything (grasping at straws) that these guys could have done. Simply seems like one of those days when your number is simply up though, can't imagine too many scenarios worse than what played out.
 
SeanD said:
Happens every time there is an aviation accident. I've noticed over the past few years, traumatic events where people die somehow get turned into Hollywood style documentaries within 2 days of the event. For example, the news media's use of flashy titles with dramatic or sad music. Its very annoying and has the most insincere feel to it. Its all about the revenue. Not that I hold YouTube to a higher standard than CNN or FOX and I get they, like any business, need to make money, but man, if they are putting an ad on that video, that is pretty low.
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As far as YouTube (not sure about other video sites) the uploader is the one that will slap the commercials onto the video. Yes. You can make a ton of money on YouTube if you are the first to post a viral video and slap a commercial on it.

Sent from my Nexus 7 using Tapatalk 2
 
WacoFan said:
Okay, some here have speculated that the load-shift may have occurred at rotation. Here are some (hopefully not stupid) questions:

How obvious is a load-shift if you feel it during your take-off roll? Would it even happen on take-off roll simply due to the acceleration?

When the load-shift occurs, even at rotation, are you better off simply closing the throttles and taking your chances with whatever is in front of you? Is there simply not enough time to process the information AT rotation and by the time you know you're already several hundred feet?

Guess I'm looking for anything (grasping at straws) that these guys could have done. Simply seems like one of those days when your number is simply up though, can't imagine too many scenarios worse than what played out.
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To add one more question, would the load master be able to contact the CPT immediately to let him/her know? I imagine in the 747 they're on the upper deck above the cargo and can't see it.
 
And another - sorry if they are stupid - but, for a freight operation, is a load-shift something that they can load in a simulator and allow practice on? Or, is it simply one of those things that the only answer is "do whatever you think, you're hosed anyway".
 
Maurus said:
As far as YouTube (not sure about other video sites) the uploader is the one that will slap the commercials onto the video. Yes. You can make a ton of money on YouTube if you are the first to post a viral video and slap a commercial on it.
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Some people would sell a video of their mom's execution if they could make a buck off of it.
 
Stall recovery question from a guy who flies light GA aircraft.

Some here have mentioned rolling one wing down in order to more quickly drop the nose (as compared to a wings-level stall recovery), which would get you to a flyable airspeed, but my experience is that: 1) The ailerons are effectively useless as you approach a stall, so rolling to knife-edge might be impossible; 2) If successful but uncoordinated it could lead to a spin; and 3) Wouldn't you more quickly recover from a wings-level stall than a wing-low stall?

I understand that there are big differences between a combat 172 and a cargo-configured 747 - I simply want to clarify or dispel that rolling the airplane to a steep bank angle will facilitate recovery from a stall. I have never heard that.
 
They stress the roll technique from a nose high attitude at the airline I work at. It rolls the lift vector with you and stops the climb. It should also get more airflow over the rudder which is a good bit bigger then the ailerons.
 
tomokc said:
Stall recovery question from a guy who flies light GA aircraft.

Some here have mentioned rolling one wing down in order to more quickly drop the nose (as compared to a wings-level stall recovery), which would get you to a flyable airspeed, but my experience is that: 1) The ailerons are effectively useless as you approach a stall, so rolling to knife-edge might be impossible; 2) If successful but uncoordinated it could lead to a spin; and 3) Wouldn't you more quickly recover from a wings-level stall than a wing-low stall?

I understand that there are big differences between a combat 172 and a cargo-configured 747 - I simply want to clarify or dispel that rolling the airplane to a steep bank angle will facilitate recovery from a stall. I have never heard that.
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Don't think of it as a stall recovery, but a full aft CG problem recovery. Most likely caused by a trim runaway or elevator failure. Not so sure it would work in a loose cargo situation, as the nose down movement could cause the load to shift again, creating a full forward CG.

What you are doing is decreasing the vertical component. The theory is, by rolling to 90*, you get the nose down to the horizon and quickly increase airflow over the wings. As AS increases, you roll wings level. The nose will immediately pitch up. Continue the roll to another 90* and back. Each evolution of roll/wings level should gain you altitude and time to trim forward and lower flaps to get the nose down. The idea is similar to what Denzel did in "Flight," although they took it laughably further by portraying sustained iinverted flight.
 
Of course... you'd need a little more than 1,200 feet in a loaded BCF to pull that maneuver off.

I guess prior to this, I never thought about how terrifying a CG shift or load breakaway could be. I mean... if it happens, you are pretty much screwed. I can't imagine being able to recover from that in a way that would give you a decent chance of survival, especially when you are dealing with cargo weight that measures in tons.
 
For those asking about the recovery technique-

The use of bank in a nose high attitude recovery aids in pitch control and avoids negative Gs. Let the nose fall through the horizon, roll wings level and pull.
 
I_Money said:
I might be alone in this belief but I think the video actually helps the profession - it will make the public want the best and most highly trained pilots (not saying these gentleman weren't), which makes you more valuable.
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I am sure you're not alone but I intend to make you think just as my college physics professor would make me think! My response to this statement is over the 35 years I have been in aviation I have notice many accidents are or have occurred with highly trained pilots with spotless records! Many safety features pilots enjoy today is the result of mainly legacy and major airline accidents over the last 43 years.
 
To the people talking about banking to help the nose-high stall, thank you. This is why we discuss accidents like this, to learn. Count me in the many who had never heard of this recovery technique and why it works. Who knows, that tid-bit of info in this thread may save someone one day.
 
Thanks, especially to those who fly the big stuff. You described stall recovery techniques in a very unlikely situation, and specific to transport category aircraft, but it demonstrates that what works in one aircraft doesn't work in them all.
 
Kyle A. said:
The video on this accident is hard to watch. Too much....RIP
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The video is bad but provides valuable clues. I would prefer to focus on the video as oppose to a bunch of pilots giving their versions of what they think happen. Now I know how a law enforcement officer feels. Facts mam, just the facts!
 
jmreii said:
I am sure you're not alone but I intend to make you think just as my college physics professor would make me think! My response to this statement is over the 35 years I have been in aviation I have notice many accidents are or have occurred with highly trained pilots with spotless records! Many safety features pilots enjoy today is the result of mainly legacy and major airline accidents over the last 43 years.
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My comment wasn't in any way to suggest these pilots weren't highly trained or had anything other than a spotless record - but the realization that in an era where airline safety is taken for granted seeing a plane crash reminds us all that their are risks and your pilots are the ones who manage them and keep us safe.
 
Interesting computer simulation of what the accident (may have) looked like from a very different angle. Might be as close as they can get, because I'll be pretty surprised if the FDR is recoverable.

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To the best of my recollection, the crash at Mather Field in California (Feb 2000) used turning to change the lift vector and modulated the turn to try to maintain altitude and some control. Ultimately, they were unsuccessful but they did make most of the circuit before crashing.
 
Stall recovery question from a guy who flies light GA aircraft.

Some here have mentioned rolling one wing down in order to more quickly drop the nose (as compared to a wings-level stall recovery), which would get you to a flyable airspeed, but my experience is that: 1) The ailerons are effectively useless as you approach a stall, so rolling to knife-edge might be impossible; 2) If successful but uncoordinated it could lead to a spin; and 3) Wouldn't you more quickly recover from a wings-level stall than a wing-low stall?

I understand that there are big differences between a combat 172 and a cargo-configured 747 - I simply want to clarify or dispel that rolling the airplane to a steep bank angle will facilitate recovery from a stall. I have never heard that.
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Don't focus on just rolling wings to redirect the lift vector to get the nose down. It's just one step of the nose high attitude attitude recovery that is taught.

As you mentioned ailerons are useless as you approach stall, so how do you roll wings if your ailerons are ineffective?

The first part of the nose high attitude recovery, before rolling wings is to reduce alpha/angle of attack, unload the wings. Once the wings are unloaded, your ailerons (and all of your other flight controls) are effective at lower airspeeds, making it possible for you to use your ailerons to roll the aircraft even though the indicated airspeed is well below normal 1G stall speeds.

There is also something called crossover angle of attack, at certain alpha the rudder becomes more effective at rolling the aircraft than the ailerons - I believe they found this investigating the 737 rudder PCU runaway crashes in Pittsburgh and Colorado Springs. So if you aren't able to reduce alpha enough to make your ailerons roll the wings, your rudder will.

You also don't need to roll the wings 90 degrees to a knife edge. While that might be fine for a military tactical aircraft, transport aircraft have sucky roll rates compared to aerobatic or tactical aircraft. Whatever you roll the aircraft to, you still have to roll the plane back the other way to get wings level. So roll it as much as you need to get the nose started down - they say no more than 50-60 degrees - at least that's what I've been taught. If you roll it too much, you'll end up in a unusually nose low attitude before you can roll the wings level.

Thrust as needed to accelerate the aircraft or decelerate the aircraft to maneuvering speed.
Recover from a nose high recovery in a slightly nose low attitude to regain the airspeed so that you can try to fly normally.
They also mentioned you'll need lots of altitude.
 
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