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

ATN_Pilot said:
That seems like a stretch, but granted, I'm not experienced in cargo ops. I'm not sure why people are so dismissive of a flight control malfunction. Seems like a legitimate possibility to me.
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It should not be dismissed at all, but I look at it this way:

Cargo Shift : Probability of a shift decreased with apparent fact that is was fine on previous leg. Weight node probability with
a. possibility that deck angle was higher out of Bagram.
b. possibility that restraints were adjusted or otherwise changed in Bagram
c. possibility of sabotage to restraints
d. possibility of cumulative fatigue to restraint system
e. other items you may think of.

Flight controls: Probability of failure after no problems on previous leg. Weight node probability with
a. Flight controls are designed for 10^-9 fail safe
b. cumulative fatigue
c. sabotage likelihood
d. other factors that might affect flight controls

Use your expertise to assign a weight to each one. Plug it into a BN and crunch the numbers.

I think you'll find the cargo shift is a markedly higher probability. Not saying the other is not what happened, just pointing out the numbers.
 
seagull said:
You are correct. In fact, a large transport WILL have roll authority through the stall, as there is still some lift, and even if the ailerons won't do it, the spoilers will. Also, the swept back plan form changes that ballgame in this respect.
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I always forget that spoilers provide roll control on some large aircraft!
 
I don't know of any large aircraft that don't have inboard ailerons and use spoilers to augment roll control offhand.
 
seagull said:
I don't know of any large aircraft that don't have inboard ailerons and use spoilers to augment roll control offhand.
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I don't think any of the big Airbuses have inboard ailerons (330/340/380). Just outboard aileron & spoiler FWIW.
 
Never flown the Airbus, so can't comment on that, but it occurred to me that was possible after I wrote that. Spoilers though, which was the main point.
 
SeanD said:
Do they always have loadmasters aboard or is it just on longer routes?
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No, not always. It depends on the type of cargo and where you're going. If the destination and departure airports have adequate know-how, the capability to do the loading on their own, and the ability to produce a weight and balance form, then the loadmaster is not needed and usually not taken. The company decides what flights to put them on and I don't know all the criteria they use to make the decision. There's almost always one on board (where I work) when going to hostile areas, Africa, or India, along with a company mechanic. Going from say, JFK to ORD, there are usually only 2 pilots and no one else because the infrastructure on both ends is adequate to handle any needs that might arise and the flight is short enough to not require relief pilots. I can't speak for how national operates but I'd imagine it to be similar.
 
Derg said:
It just really depends. If you've rotated, the chances of getting back down on the remaining runway is pretty slim, and you're going to somehow want to get the aircraft stopped on a surface that's not very forgiving.

I don't mean to prejudge the event ahead of the findings of the investigation, but they were dealt an unwinnable hand if the cargo shifted, especially that low.
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I would say at just about any altitude.
 
Saw a picture of the site this morning... not much left. National chartered an Ameristar MD83 and picked up the families at YIP and flew them to DOV where the crew members were brought home by the USAF. Glad to see they're at least coming home.
 
KHanson said:
Assuming what happened to this poor 747 is like a grandma saying "that flight was bumpy"... What exactly is the point?
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I don't think any one is assuming. Speculating? Sure. I don't think anyone here (well, except for the few actually qualified to do so) is saying that something DEFINITELY caused this accident. But certainly speculating. Is that so wrong? I don't think so. Not sure about anyone else, but I've already learned a great deal in this thread. Every time there is a crash, a thread gets started here, a bunch of folks (including myself) take somewhat educated guesses based on what little we do know about the accident. It builds critical thinking skills (I know I would definitely recall things mentioned in this thread should the nose of my plane go straight up, God forbid) and educates folks on possibilities, scenarios, and potential solutions that they may not have otherwise considered.
 
Hacker15e said:
Here are two more posts from over at baseops.net; can't speak for the authenticity/accuracy of the comment or the photos they saw.

http://www.flyingsquadron.com/forum...ash-at-bagram/page__view__findpost__p__346925

http://www.flyingsquadron.com/forum...ash-at-bagram/page__view__findpost__p__346954
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:eek: Goodness gracious. I wouldn't take an MRAP on the highway via 18-wheeler strapped down like that, much less in the air. I see something as big and heavy as an MRAP, and the first thing I think of for tie downs is chains. And not the swing set kind, either.
 
seagull said:
I don't know of any large aircraft that don't have inboard ailerons and use spoilers to augment roll control offhand.
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Boeing 757. Outboard ailerons only, with spoiler augmentation.

Of course, that might not count as "large" for you "professionals" flying widebodies. ;)
 
SteveCostello said:
:eek: Goodness gracious. I wouldn't take an MRAP on the highway via 18-wheeler strapped down like that, much less in the air. I see something as big and heavy as an MRAP, and the first thing I think of for tie downs is chains. And not the swing set kind, either.
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One inch tubular webbing is used for rock climbing, and it can withstand 22 kilonewtons of force. Now, I'm not good at math, so I used some calculator on the internet and it says that this means it can withstand 4945 pounds of force, if it's to be believed. Dynema, which we also use for climbing, and is 9/16th of an inch wide has a strength of 27 kilonewtons, which results in 6069 pounds of force. Both of these are static forces (which means that you're hanging on it, not falling on it, extending it, and thus shock loading it).

So don't discount webbing just because it isn't metal, that crap is stronger than you might think. Where you generate force isn't by holding something down that isn't moving, you generate it by trying to catch a moving object. So when you take a 15 foot fall while climbing, with a 175 pound body, you can generate upwards of 15 kilonewtons of force. Again, if that calculator is to be trusted (and if I understand the physics correctly, which I may not), a static 175 pounds is 0.77 kilonewtons.

So unless one of those trucks was moving because it wasn't tied down properly, then those straps would probably keep it where it needed to be.
 
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