747 Cargo Plane crash (dash cam)
by R. Proffitt - 4/30/13 4:59 PM
Not much word out about it yet.
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by: R. Proffitt April 30, 2013 4:59 PM PDT
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Total posts: 16 (Showing page 1 of 1)
Less than 48 hours ago
At least from the posting. I wonder how long since it happened. Didn't see any rescue attempts, any fire trucks, nothing.
(NT) It just crashed.
The plane was too far from Bagram Airbase for Emergency
Response vehicles to have arrived, James. Probably about a mile from the end of the runway judging from the height. A very strange crash. It doesn't seem like something any experienced or even novice pilot would have gotten themselves into (the extreme stall condition).
I watched it, saying, "That's a stall! That's a stall!" be4
the aircraft even started to wobble. The aircraft was at much too high an angle of attack to sustain airspeed despite its large engines. There's just not enough thrust to power that aircraft at a climb angle like that. Even someone who has only flown RC planes, and has taken the controls on half a dozen private planes (one illegal take off, no landings) could figure it out from a dash cam.
A stall occurs when the angle of the wings to the air is too acute to permit sufficient lift over the wing, actually disrupting the airflow, and engine power or thrust is insufficient to overcome the weight of the aircraft and its drag.
The dropping of a wing is a classic response of the aircraft to a stall, and the situation was only made worse by the correction to the pilot's right, resulting in further drag and the other wing dropping irrevocably.
I have to say, it surprised me. I wonder if there was a mechanical failure causing too much up elevator. It seems too simple an error for any pilot to make intentionally.
Angle of attack = wings angled above the straight and level, or the datum line.
That's a common tactic in a war zone..
by Tony Holmes - 5/1/13 4:35 PM
In Reply to: I watched it, saying, "That's a stall! That's a stall!" be4 by Ziks511
to gain altitude as quickly as possible to get away from any hostile fire.The pilot was trying to do this :
It definitely stalled and snap rolled into the ground and probably didn't have anything to do with pilot input.The aircraft was loaded with military vehicles which are held by tie down straps and should be further secured by redundant chains.It's possible the chains were left off or installed incorrectly/failed resulting in a cargo shift.
Observers on the ground report seeing the nose suddenly rise while the craft was in that climb also indicating a cargo shift.The crew also radioed of a possible cargo shift while climbing out.
"Several observers on the ground reported the National Air Cargo Boeing 747-400 had just lifted off and was climbing through approximately 1200 feet when it's nose sharply rose, the aircraft appeared to have stalled and came down erupting in a blaze.
According to a listener on frequency the crew reported the aircraft stalled due to a possible load shift."
He had 5-6 effective seconds to realize a drop in airspeed allowing maybe a change in attack angle during takeoff. I don't see any sudden increase in the angle indicating a shift in equipment. Those loadmasters double and triple check loads before takeoff and keep checking during flights. I think he tried to climb too steep too quickly for the engine power available. I also don't see any obvious signs of engine failure, but exactly what would be expected in a stall due solely to maintaining too steep an angle during takeoff. I think this will come down to pilot error, maybe due to instrument malfunction, or maybe not realizing the limitation of the particular aircraft he was flying. Does the civilian 747 have less powerful engines than the military version of it?
You're like me,looking over and over,analying..
did you happen to notice the landing gear was still down when it crashed? It should have been raised as soon as it started to climb out to clean up excess drag.That's the only possible pilot error I can spot.Perhaps the error was on the loadmaster or the people that loaded it.It was a civilian plane not military and it's not clear at this point if any Afghan civilians/military helped load it.
I'm not about to second guess an experienced pilot but perhaps he had more pressing issues on his mind than raising the gear such as a load that had started to shift on him? He has already commited to the climb and his only out is to pour on the power and hope the plane gains airspeed.A rapid C/G shift to the rear would nose up and doom the plane.At that point,the pilot's only alternative is to grab the plastic Jesus on the dashboard.
It's hard to tell from the viewing angle if there was a change in pitch,the footage was from a base security vehicle and the crash occurred in the base perimeter.It was reported by observers that there was a sudden nose up while in the climb.
Yes,those engines are much more powerful than a passenger 747 and even the C17 Globemaster.The passenger version of the 747 has 56,000lbs thrust per engine.The 747C cargo version is a larger plane and has 63,300lbs per engine.The Globemaster in that link has 40,400lbs per engine.
I was thinking
a former military pilot with stronger engines on the same airbody flown, might have forgotten the civilian version couldn't climb at the same steep angle on takeoff, if the engines are less powerful.
If you'll pardon me,I'll invoke a Mythbusters episode..
It's hard to imagine that they actually got a major cargo carrier,"Kalitta Air" to cooperate with them!
This clip demonstrates how powerful the engines on a 747 cargo plane are.The Kalitta pilot locked the brakes and ran the engines to full throttle while the Mythbusters towed a school bus past the rear of the plane.
The bus lifted 8ft in the air and blew away like a feather,truly impressive!
Just my 2-cents
by Willy - 5/2/13 6:30 AM
In Reply to: If you'll pardon me,I'll invoke a Mythbusters episode.. by Tony Holmes
Yeah, but the bus has a flat area to catch the thrust and space beneath to cause airflow to start the lift. All that bus has is its weight and tire contact to remain where it is. As soon as that bus was broadside, all bets are off.
As I've seen military planes take-off its impressive and no mufflers. It's not uncommon for quick vertical climb as soon as possible. the best take-off I've ever seen is a "Habu" or SR-71 or military black plane. That's gets your attention and those blue dots(burners) faint quickly. -----Willy
Damn,I've never even seen an SR-71 in person...
the best I can counter with is an F4 Phantom under full after burner,impressive and deafening
Here's another one for ya...
I'm sure you had a bug on the car windshield that seems as fast as you were going it stayed. Regardless, that its plastered there for whatever reason, it can impress you. Well, one time, I was on a commercial flight on take-off and looked out the window. Taxing as were building speed was a "dragonfly" by the rear of the wing. It stayed with us as the bumpie da-bump of building speed and you can feel it, that dragonfly kept on flying. Until, I believe we're about to lift-off and it got blown or it peeled away in an instant. I'm sure it was stuck in the air stream of the plane, but I believe speed had to be 150-180mph so that dragonfly was booking. -----Willy
At Pendleton I see the Osprey every week. Near MCAS Miramar (yes that one in Top Gun) there's quite an assortment of aircraft. Including some I'm never seen before.
Here's my observation.
It appears the forces are indeed getting by with less aircraft. But wait a second, the ones I'm seeing look to be super sized.
Been like that for yrs.
I *assume* that what you're seeing is what is left or needs repairs, etc.. There is simply too many deployed right now and/or becomes the spares of what's in an active deployment. Yrs. back that was the opposite and stacking of whatever was common. Also, there are budget restrains I'm sure as they can't replace everything at once. In the 1st Gulf war, there was shortage of "BULLETS"!!!! Come on, you don't have enough bullets, sit it out. Nope they requested or borrowed until payback the bullets they needed. Anyways, the USMC gets by with little all the time. For JC sake, I had to make "radio telegraph" to a working condition just in case some mushroom took all the fancy stuff down.
As for the Osprey, I'm glad not to have flown in one. They were on the drawing broads when I left and they didn't get near a base until many yrs. later. They simply were too complicated and the men needed training to keep them up and running. Helicopters are OK by me. -----Willy
Your info makes a great deal of sense. A sudden shift in
Centre of Gravity, i.e. a cargo shift makes the sudden steep climb far more understandable. I read about a similar occurrence just after WW2 in India where a field gun broke loose and rolled aft destroying the aircraft's trim and ultimately causing the a/c to crash.
I do recognize the emergency climb to clear dangerous airspace, but my eyes though old are still attuned to what looks dangerously too steep. I'm not comparing model aircraft with the real thing, just that eyes which have learned to assess aircraft at a distance, whether smaller or larger, are well enoughschooled to recognize disaster when they see it..
Spitfires were found to have a very critical range of CofG, on the order of 16 inches of travel, and as they developed, and more and newer equipment was loaded on, the trim moved aft, resulting in a spate of unexplained disintegrations in the air. Finally, a Wing Commander who had spent time as a test pilot at Farnborough (the Royal Aircraft Establishment, the chief research airfield in Britain then as now) pulled out of a dive, and found the elevators so effective he was thrown forward far enough to be knocked senseless on the stick despite his straps, and to pop most of the rivets on the top surface of the wing. The good news was that he regained consciousness just as the aircraft stalled after a fairly long climb, and well clear of the ground so he was able to bring the aircraft home. Jeffrey Quill, Chief Test Pilot for Vickers Supermarine in the south, checked as many squadron aircraft as he could over the next weeks and found 90% of them to be dangerously out of trim. A very simple fix was found but loading and trimming instructions to the squadrons were made most emphatic. The further aft the CofG moves, the more sensitive the elevators appear to be, and the harder the aircraft is to control. Of course with a major cargo shift, there's bugger all you can do about it. Slamming the nose forward to straight and level, just won't work.
James, Your assessment too appears to be spot on, though I couldn't get a long enough view of the dash cam to make a reasonable asssessment. When the a/c appears on the dash cam, it's already in deep trouble, but I'm sure they simply didn't have either the time or sufficient strength to counteract the cargo shift. Damn shame..
Total posts: 16 (Showing page 1 of 1)