What response is expected from the pilots?
I would guess the pilots are expected to keep a cool head throughout the crisis, and do whatever they can to make for the gentlest touchdown they can possibly manage.
You really don’t want a pilot who responds to a seemingly untenable situation by folding his hands in his lap and saying “well, we’re fucked.”
In the thread on Air France off Brazil a year or more ago, a pilot mentioned that stalls in a large aircraft are not the smooth, quiet experience of a Cessna.
In the video, it looks like the plane drops one wing overcompensates by dropping the other, then levels out and maybe was in the process of recovery, wings level and nose down, would have actually recovered if there had been enough altitude. I don’t see evidence of cargo shift.
I wonder hwo effective the tie-downs are? Would one load coming loose have a pinball effect all the way? If so, wouldn’t you expect to see the cargo popping out through the fuselage? I don’t imagine the doors are that strong compared to heavy equipment.
Looks to my untrained eye like a simple stall.
Fight my ignorance:
It’s my impression that landing gear causes a lot of drag. Wouldn’t you want less drag in a stall? Why leave the gear down?
Stall is purely about exceeding the critical angle of attack, not drag. It can happen at any airspeed.
The crew may have elected to leave the gear down in the expectation, or hope, of recovering and landing successfully.
If you look at the video the plane is wing down 90 degrees and then rights itself just before impact. Either it just leafed down toward the end or the load shifted enough and they still had enough air flow for the ailerons.
Looking at the picture of how these are strapped down I’m trying to imagine what happened. It’s unlikely all the straps broke but if you have one set of straps mostly keeping it from going forward and one set mostly keeping it from going backwards then it likely slid in an arc with the side straps eventually doing the work of the front straps that failed. That means the vehicle is not tumbling inside the plane which would absolutely destroy the aircraft. When the plane arced over sideways and nose down then the truck probably slid forward again. If they had more altitude they might have survived this. But again, they landed at the end of the runway so the flight path was straight up. It was a hammerhead stall with no altitude to recover from.
FYI, I’m good friends with a loadmaster who does this same load in the same aircraft type from the same airport. He says you can’t put too many straps on these things. Forgot how many he says he uses but it greatly exceeds the number required based on the strap load capacity.
There’s no conspiracy, he just forgot/didn’t bother to set the clock.
I would think too many straps would put a lot of stress on the tie-downs. Wouldn’t want to pull them out of the floor.
No. If anything adding load points will actually spread the stress placed on the floor more evenly.
I don’t personally agree with training scenarios where the expected result is a crash (what is the intention of the exercise?), however wind-shear training in general makes a lot more sense than training for a cargo load shift. Wind-shear of some sort is encountered relatively frequently and there is a set procedure for how to deal with it. Wind-shear training is conducted regularly in my company and I’ve sometimes only had 10 feet to spare during the recovery (recovery is not guaranteed by any means.)
A load shift or similar event is a bit different in that it is more rare and there is not a lot you can do about it other than try and fly the aeroplane. If you’ve been presented with a flyable aeroplane then you are good, if not then not. If it is right on the cusp then you might get away with banking so that the pitch up is translated into the horizontal plane and you may be able to get enough airspeed while turning to get enough tail-plane/elevator authority to fly more normally.
Simulator time is expensive and needs to be used wisely. Training for rare high risk events needs to be balanced against training for more common lower risk events. Common high risk events are obvious but there comes a point where, no matter what the risk, if an event is rare enough it is not worth dedicating simulator time to. I see scenarios such as gross miss-loading/load shift as something to be talked about in the crew room and maybe played with in the simulator if there is time to spare at the end of the session but not to be trained regularly at the expense of other training exercises. I think that if this crash was a result of a load shift then it is no more the result of inadequate training than the Sioux City DC10 crash was.
What would evidence of a cargo shift look like and how would it look different to a simple stall?
There are only 4 likely possibilities:
- The pilots of fucking crazy
- the elevator stuck in full up deflection
- the plane was out of CG to begin with.
- the freight shifted in a way that could not be compensated for with elevator trim.
I think it’s safe to rule out #1. You don’t get into a 747 cockpit without knocking out a few flight hours. The elevator trim could have jammed and that’s happened before. The Emery DC8-71F crash at MHR in 2000 was an example of that. That would come out in the investigation. It’s unlikely that it was loaded wrong since it’s done by computer and checked by a couple of people and then verified by a walk-through.
Supposedly someone overheard the cockpit-to-tower conversation and it involved freight shifting. If there isn’t any mechanical reason such as pilots setting the trim wrong or a mechanical failure of the trim then it’s pretty much a case of the load shifting. That happened to a Fine Air DC8-61F at MIA in 1997.
this. posting picture again for reference.. there are a zillion places to attach a strap on the floor.
If they were all hooked to just a couple of spots it would indeed tear the floor up.
Thats a good point. In THEORY you only need X number of straps. And yeah each strap in THEORY can take the load.
But maybe that strap wasn’t connected right. Or the point it was connected to is weak. Or some dipshit was washing the straps with clorox. Or gawd knows what.
And yes, you can overdo things. But a bunch of straps compared to tons of stuff being hauled aint exactly one of them.
At best IMO you need to have at least two relatively unlikely failures (of relatively independent systems…or in other words 3 straps connected to same point on the floor doesn’t do much good if the floor point fails) of your tie down system before the shit hits the fan. And you can’t have it so that when one fails, the increased load pushes the next to the limit because that will possibly result in a “zipper failure sequence” (for lack of more technical term).
Billfish (load master of many a canoe, kayak, and random crap being hauled various places…and wearer of belt and suspenders and modest briefs). People make fun of me, but rarely has my shit gone flying. And that whole "no slip knot thats easy to untie and also easy to adjust? Bullshit.
I was trained as a loadmaster but only made one commercial flight before my company shut down. what was scary for me was the damn floor locks that recessed into the floor when not in use. Those things could appear fully locked in the up position but fall over with a good breeze. You had to inspect each lock and make sure it was solidly locked.
What caught my eye, and I’ll have to ask about it when I see my buddy again, is the blocking under the truck. It looks like they block it on the pallet and then chain the truck to the pallet.
I’d be so paranoid after this crash that I’d have someone weld up an aluminum brace that transmits all the load on to a line of locks on the floor. Let every damn strap break and it isn’t going past this point. It would be worth the money to rent an engineer and a welder for a couple of hours. It would also work nicely for long pieces of pipe. Those things are scary loaded into a freighter.
Thats a damn good idea Magiver. Not only do straps keep it from moving around your brace does as well. Minor additional aggravation that allows alot more strap failure before shit hits the fan.
Note, I have only seen the cargo area of said planes a few times and only have a vague familiarity with them.
Looking back over the years of air freight, nobody respects people with any common sense. I remember getting a request for an extremely dense piece of freight. It would have spanned a couple of positions and the weight exceeded the lbs per sq/ft load of the plane. It looked like a nice little piece of extra $$$ for the flight but to do it right required placing wood under it to spread the load out and that required an engineer to say how much and what kind of wood to use. All I got was a bunch of “we move that kind of weight all the time, it’s good revenue”. I had had to hunt down the chief pilot who gave a big thumbs down on it for reasons stated. Had we moved this freight it probably would have done a number on the ball mat which would have added a chunk of extra cost to the next heavy-check. It just never occurred to anyone that that heavy loads which bend the fuck out of aluminum pallets would damage a series of 2" rollers set into the floor.
If you read your link from post #18, it says:
That seems to rule out option 3. If the cargo, as loaded, put the plane’s CG aft of the limit, it probably would have crashed on the first leg, from Camp Bastion to Bagram.
I suppose there are other scenarios to consider. The takeoff and climb from Camp Bastion may have been done at a speed that gave the plane sufficient elevator authority to avoid a stall. The refueling at Bagram may have moved the CG from where it was on the earlier leg.[sup]*[/sup] Or a combination of the two. Those seem unlikely to me.
- The 747-400 series can carry fuel in the horizontal stabilizer. If those tanks were filled, it certainly wouldn’t have helped.
I agree with you, and I meant to comment more on this (had to leave unexpectedly yesterday). I thought that scenario was odd, and the only reason I could see was teaching acceptance of the fact that you’re not going to stay in the air (and preparing for that, rather than desperate attempts to raise the nose further).
I actually got to ride in the jump seat for part of this, and it was surprising how many visual and aural warnings were going off when the airspeed dropped. Since it was a full-motion sim, you could actually feel the deceleration when the IP introduced the shear. To his credit, Son detected the change immediately, and called for max power. His acting FO was too tentative (gradual) and Son actually slapped his hand away as he shoved the levers to max. It still wasn’t enough, and the IP stopped it after we hit the runway again (that was surprisingly jarring also). He than explained that it was an unrecoverable situation that was part of the syllabus, and that no one could fly out of it. I expected him to explain further, but he reset to the threshold and continued on.
Anyway, sorry for the slight hijack, as this is only tangential to the OP’s subject.
I read on another forum that those MRAPS are secured with no less than 70 (yes, 70) straps. I’d think they would be pretty careful since their lives are on the line. Most aircraft accidents that are not pilot error (low level aerobatics, for instance) are the result of a chain of events and not a simple cause. We’ll just have to wait until the investigation is complete. One thing I’ve learned after a career of conducting investigations (not aircraft accidents) is that things often aren’t what they first appear to be.