Severe turbulence LHR-SIN. One dead.
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Twenty-two with spinal injuries is a sobering thought. How many of those will be parapalegics?
As a cabin passenger, bad being hit by an unbelted passener sitting next to you, much worse hitting your head on the panel above because you've not belted in. If you think about it, in most of the cabin seats, for the most part, "up" is the primary direction of body movement for which the surrounds do not already have an effect to contain you. It makes the seatbelt seem like an extra good idea when you think about it. Occasionally, I "politely suggest" to the person seated next to me that they stay belted in. Usually it goes okay. But I can scare the hell out of someone with a truthful "been there, done that" life story if I need to!
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Looking helps.
However, what about the radar ? That post about the embedded CB caught my eye.
Starting to think that a nearer cloud could have weakened the returns of whatever was behind, like a growing CB.
Thinking that this might have been the case here.
Still, the million $ question is, why this aircraft didn´t avoid the active CB area by a margin ?
However, what about the radar ? That post about the embedded CB caught my eye.
Starting to think that a nearer cloud could have weakened the returns of whatever was behind, like a growing CB.
Thinking that this might have been the case here.
Still, the million $ question is, why this aircraft didn´t avoid the active CB area by a margin ?
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I wouldn't be surprised if, unable to contact Yangon VHF for Wx deviation, the crew didn't want to break the rules and deviate without clearance.... so they didn't. The seat belt sign was put on just before the incident, so they were aware of Wx. They just didn't avoid it.
Be interested to see the crew details.
Be interested to see the crew details.
I was in a MEL to CBR flight with a sustained period of low level turbulence. Before it really set in the cabin crew brought around the drinks trolley. The passenger next to me asked for red wine.
He then decided it was too bumpy to actually sip it without risking spilling it over his shirt. He just sat next to me holding it in his hand in front of him and trying not to spill it everywhere.
He then decided it was too bumpy to actually sip it without risking spilling it over his shirt. He just sat next to me holding it in his hand in front of him and trying not to spill it everywhere.
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According to the broadcast media in UK this morning, the deceased suffered a heart attack. Condolences to his family and friends.
While such a rapid descent may be within limits to you guys up front, it's certainly NOT seen as normal to anyone on the other side of the closed door, whether they be crew or paying passengers. I feel that some on here need to be reminded of that, and if it was a deliberate descent, a quick warning wouldn't have gone amiss. Given the apparent damage in the cabin, it doesn't seem that NORMAL to me.
While such a rapid descent may be within limits to you guys up front, it's certainly NOT seen as normal to anyone on the other side of the closed door, whether they be crew or paying passengers. I feel that some on here need to be reminded of that, and if it was a deliberate descent, a quick warning wouldn't have gone amiss. Given the apparent damage in the cabin, it doesn't seem that NORMAL to me.
I am really pleased to be able to share this with you, the first hand account of the Andes Incident in G-ASIX by Captain David Phillips, the pilot in command of VC10 ASIX. A fascinating read and an important record of that flight and what happened that day.
FLIGHT OVER THE ANDES
By
Captain David Phillips
It was not easy, playing Scrabble, on the flight from Freetown to Buenos Aries. Although the letters had little lugs on them to prevent them sliding out of position, they were not really designed for the turbulence experienced in a Tropical thunderstorm, and we had been encountering such storms for most of the nine hour flight. We were, of course, flying directly along the Inter-Tropical Front all the way across the South Atlantic and, although we had slowly climbed when the aircraft gradually became lighter as we burnt off fuel, there was no hope of topping the enormous anvil topped clouds that seemed to go up to God.
We had departed from Freetown long before dawn in our Vickers VC10 aircraft, and the majority of the journey had been flown at night with flashing lightning, which never seemed to switch off, all around us. My First Officer, Tony Cutting and I had spent much of the time with our eyes glued to the weather radar, turning and weaving our way around the greatest areas of thunderstorm activity, and between times, in the brief intervals of relatively calm flying conditions, we had relieved the tension with games of Scrabble which we shared with our Flight Engineer, Jock McCann.
As we neared the Brazilian coast the clouds began to thin, and by the time we had reached the entrance to the River Plait, passing South of Montevideo, the skies were completely clear and, commencing our descent we could see the sprawling city of Buenos Aries ahead of us on the South bank of the river.
It had been a strenuous flight and we were all tired, but we still had the prospect of a further two hours flying to our final destination of Santiago in Chile, the other side of the Andes range of mountains. Tony and I left the aircraft, while Jock arranged the refueling, to stretch our legs and to have a word with our Agents and to pick up the latest weather forecast for the flight. "Do you think you will ever get your twenty thousand hours?" Tony asked me, for no particular reason, we certainly hadn't been discussing flying hours or experience. "I already have over twenty thousand" I replied, and thinking that it sounded as if I was boasting I added "Not that it means very much, I have just spent a long time in the air enjoying myself and being fed food and coffee by beautiful women, who could ask for anything more?" Then, thinking that I was not doing myself full justice, I added "If it means anything atall, it just means that, by the law of averages, everything that can happen to me in the air has already happened. I have been lost on occasions; I have run short of fuel, had my crash landings, experienced engine failures, engine fires, and even cabin fires, what more can possibly happen to me"
Never, Never again will I tempt fate by making such a sweeping statement. God must have been listening to every word I said, and was muttering under His breath, "David Phillips, if you think everything that can happen to you in the air has already happened you definitely have another think coming!" If only I had heard Him, I would never have taken off on that last leg across the Argentine and Andes to Santiago.
Having refueled the aircraft, and loaded on some passengers, including the ex-President of Chile, President Frei and his family, we were airborne once more on the last leg of our journey, heading Westward towards Santiago. It was now an almost cloudless day, the sun was shining, and as Tony climbed the aircraft to our cruising altitude of thirty three thousand feet, we all relaxed on the flightdeck, and started looking forward to a pleasant evening in Santiago.
Heading West over the Pampas we passed over Rufino and altered course slightly to head for Mercedes on the Southern edges of the Sierra de Comechingones. The land below us was flat, and punctuated by large haciendas, (ranches), the very centre of the Argentinian cattle industry.
Passing over Mercedes the ground ahead was slowly rising and, in the far distance we could see the faint outline of the Andes range of mountains. We were now heading for Mendoza, the Argentine's second largest city which lies on the Eastern edge of the Andes themselves. The Andes at this point rise to twenty three thousand feet, and our flight path after Mendoza would take us about twenty five miles South of the highest point in that area, the mountain Aconcagua.
Having, in the past, encountered severe turbulence over the Andes, even in clear weather, I switched on the seat belt sign as we approached Mendoza, and the senior cabin staff member came up to report that all the passengers were safely strapped in. The visibility was excellent, but, just above the height at which we flying there was a whisp of cloud, and ahead and just to the South of Aconcagua there was an unusual cloud formation consisting of a little hook of cirrus cloud hanging below the rest. Never having seen a cloud formation quite like it before, I suggested to Tony that we should alter course slightly to the South to avoid flying directly below it.
After Mendoza there was only about ten minutes flying time to the top of our descent into Santiago, the Andes being very narrow at this point, but from experience I was well aware that they could be the most difficult ten minutes of the entire flight.
Suddenly, and without any warning whatsoever, our hitherto smooth flight became a nightmare, and we were grabbed by an unseen hand and treated like a rat shaken by a terrier. We dropped like a stone, only to be lifted up again, forced into our seats, the wings tilted until we were, from time to time, flying vertically on our sides. At this stage it was impossible to read the flight instruments, our eyeballs vibrating at different frequencies from the instruments themselves. During an occasional lull in the turbulence I was able to see that our altitude was now twenty eight thousand feet, only to be followed by a later lull that showed that we had been thrown up to thirty five thousand. Tony suggested that we ought to turn around and get out of it, but there is one golden rule under turbulent conditions, and that is that to turn around is the most dangerous thing that one could do, trying to fly straight and level was impossible and if we deliberately applied bank we would almost certainly find ourselves upside down!
By this time everything that was not firmly attached to the aircraft was floating around the flight deck and chaos reigned supreme. On two occasions the high speed warning horn sounded, indicating that we were approaching the speed of sound and this was at a time that I had the airbrakes extended and the throttles closed! At another time the stall-warning system operated showing that we were approaching a stalled condition, and at the time I had applied full power with the nose of the aircraft pointing down towards the mountains. The elevators appeared to have no effect and I even pulled the airbrakes which normally gave a slight pitch-up effect, and, fortunately, the aircraft slowly responded.
During the initial stages of the turbulence I was quite enjoying myself, man's eternal battle with nature, pitting my skills against the elements and all that sort of thing, with something of the elation that must have been experienced by the captain of a Clipper ship rounding the Horn. but when I heard a great cracking sound I was convinced that the tail had come off, (we were always a little sensitive about the high 'T' tail on the VC10), and after that the adrenalin really started to flow, and to say I was frightened would be an understatement!
Perhaps it was just as well that my radio headset had flown off in the extreme turbulence, (as it did so, knocking off some relatively unimportant switches in the overhead roof panel), thus preventing the rest of the flight crew from listening to the profanities that must have been coming from my mouth, but at the same time it necessitated me shouting my demands for more or less power to Tony, the First Officer and Jock, the Flight Engineer, as the circumstances dictated.
Fortunately in life, it is seldom that one experiences the certain knowledge that one is going to die, that there is no possible hope of survival, but that is exactly the state I was in at that moment. It was no longer a question of asking myself if the aircraft was falling to bits around me, I was certain that the tail had parted from the rest of the tail assembly, and that, very soon, we would be falling into a very untidy mess in the desolate areas of the High Andes. We are often told that, at such times, one's whole life flashes before one, but I cannot say that I experienced anything like that, I was full of abject fear and it was all I could do to speak and to continue issuing instructions to the rest of the crew. But it is surprising how one's training and background stand one in good stead at such moments, and without being conscious of it, I continued to fly the aircraft and to shout orders although I knew it was pointless and survival was impossible.
As the entire episode was taking place in clear air, it was possible, from time to time, to have a vague idea of the horizon ahead,(when my eyeballs had a chance to settle down for an instant), and to know roughly the attitude of the wings in relation to straight and level flight, but it did me little good because the controls were seldom responding to the demands I gave them. On one particular and memorable occasion the aircraft had banked itself into a slightly inverted position, and it seemed forever before the wings slowly responded to my demands on the control column, and resumed a more or less normal attitude again.
The lack of response by the aircraft to control wheel demands was, it was subsequently decided, because the controls themselves were operated by a system of electro-hydraulic motors which, during the extreme conditions of turbulence, were being starved of hydraulic fuel and thus rendered, for a short period of time, useless. But we were not to know this, and as far as I was concerned, the aircraft was in a state of rapid disintegration!
Just at the moment that I had decided that no man-made bit of machinery could stand such treatment, the whole ghastly experience stopped as suddenly as it had begun. My eyeballs settled back into performing their normal functions, I could see the horizon again and read the flight instruments, and I could once again feel the aircraft responding to my control demands. The bodily flow of adrenalin does not, however, respond so quickly to new circumstances, and it was some minutes before I was able to speak coherently to the crew and to resume my normal duties. I was not alone in my feelings as was evidenced by the crew when we discussed the entire incident when we were safely back on the ground.
An impression of a Caledonian//BUA VC10 flying high over mountains
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I was in a MEL to CBR flight with a sustained period of low level turbulence. Before it really set in the cabin crew brought around the drinks trolley. The passenger next to me asked for red wine.
He then decided it was too bumpy to actually sip it without risking spilling it over his shirt. He just sat next to me holding it in his hand in front of him and trying not to spill it everywhere.
He then decided it was too bumpy to actually sip it without risking spilling it over his shirt. He just sat next to me holding it in his hand in front of him and trying not to spill it everywhere.
Yes. "Spinal injury" is a general description. Depending where along your spine the injury occurs, the outcome could be anything from a little annoying for the rest of your life, to life changing. When I imagine neck injusries from vertical head srikes, that's about as bad as it gets. I was a patient in a spinal injury clinic for three weeks, and met the full range of recovering spinal injury patients. Happily I walked out, some did not. But from what I saw there, I sure think about protecting my neck!
As a cabin passenger, bad being hit by an unbelted passener sitting next to you, much worse hitting your head on the panel above because you've not belted in. If you think about it, in most of the cabin seats, for the most part, "up" is the primary direction of body movement for which the surrounds do not already have an effect to contain you. It makes the seatbelt seem like an extra good idea when you think about it. Occasionally, I "politely suggest" to the person seated next to me that they stay belted in. Usually it goes okay. But I can scare the hell out of someone with a truthful "been there, done that" life story if I need to!
As a cabin passenger, bad being hit by an unbelted passener sitting next to you, much worse hitting your head on the panel above because you've not belted in. If you think about it, in most of the cabin seats, for the most part, "up" is the primary direction of body movement for which the surrounds do not already have an effect to contain you. It makes the seatbelt seem like an extra good idea when you think about it. Occasionally, I "politely suggest" to the person seated next to me that they stay belted in. Usually it goes okay. But I can scare the hell out of someone with a truthful "been there, done that" life story if I need to!
Amazed at how many are just ignoring it or even arguing with cabin crew. Not just about urgent trips to the loo but getting cases down out of lockers, generally just milling around and chatting or simply the adults now who obviously were never taught the word ‘no’ as a child. Then there’s the sooks who just can’t bear to have the seatbelt on where they’re seated- it’s just oh so uncomfortable. What a load of crap. I sit for 16-18 hours each weekend with it fastened- most of the time forget I’ve got it on! I just don’t feel it! So I’m not sure what on earth they’re going on about. Just another case of spoilt brat adults.
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Then there’s the sooks who just can’t bear to have the seatbelt on where they’re seated- it’s just oh so uncomfortable.
Reading the various posts here discussing efforts to derive accelerations that may have been experienced, media commentary about the 6000 ft loss in altitude, possible aerodynamics of the 777 in this event etc, I was prompted to do a quick search for simulation of aircraft encountering severe turbulence. First item I found wasn't what I was expecting, but a gem all the same. It is a 13 August 1964 report from the US Naval Air Development Center (NADC-ML-6411) titled "Simulation and Effects of Severe Turbulence on Jet Airline Pilots" (https://apps.dtic.mil/sti/tr/pdf/AD0448067.pdf). The report presents results of testing of pilots in a human centrifuge to investigate factors contributing to commercial jet aircraft crashes associated
with encountering severe air turbulence. The first step was to determine whether the vertical accelerations obtained from the flight recorder of a United Airlines Boeing 720-B, Flight 746, N7213U which encountered severe turbulence on 12 July 1963 could be reproduced with the centrifuge. That was broadly possible. The report contains a time trace of the vertical accelerations, altitude, airspeed and heading recorded by the Fairchild 1127 flight recorder for that event. I am including this as an extract.
Interesting to see in the trace that vertical accelerations ranged from about +3g to -1g (with +1g representing steady flight prior to turbulence encounter). Also interesting to see that the measured vertical accelerations were a combination of higher frequency oscillations and an underlying lower frequency oscillation. However the low frequency oscillation 'ended' with a 22,500ft drop from about 35,000ft to 12,500ft over a period of only around 1 minute and the start of this 'dive' corresponds roughly with the highest negative accelerations. It is almost like a rollercoaster going over edge of a crest at the start of its run. There is no suggestion in the report that the pilots intentionally dropped 22,500ft. This drop is significantly greater and also more rapid than the 6,000ft drop over about 3 minutes being reported for the Singapore Airlines flight.
There is also a correlation between the altitude trace and the low frequency trend of the measured vertical accelerations, but I haven't attempted to integrate altitude variations to try to derive expected vertical accelerations. I didn't notice any discussion in the report about where the flight data recorder was positioned in the Boeing 720-B, but I assume it was somewhere in the tail and so would have also measured a component of pitch motion induced vertical accelerations, not only vertical accelerations at the aircraft CG.
The report noted a consistent pattern of test pilots making inappropriate pitch control movements on encountering of negative vertical accelerations. I haven't read the report in further detail to understand the basis of this observation, but I wonder if this trend remains with modern airliners if flown 'manually'?
with encountering severe air turbulence. The first step was to determine whether the vertical accelerations obtained from the flight recorder of a United Airlines Boeing 720-B, Flight 746, N7213U which encountered severe turbulence on 12 July 1963 could be reproduced with the centrifuge. That was broadly possible. The report contains a time trace of the vertical accelerations, altitude, airspeed and heading recorded by the Fairchild 1127 flight recorder for that event. I am including this as an extract.
Interesting to see in the trace that vertical accelerations ranged from about +3g to -1g (with +1g representing steady flight prior to turbulence encounter). Also interesting to see that the measured vertical accelerations were a combination of higher frequency oscillations and an underlying lower frequency oscillation. However the low frequency oscillation 'ended' with a 22,500ft drop from about 35,000ft to 12,500ft over a period of only around 1 minute and the start of this 'dive' corresponds roughly with the highest negative accelerations. It is almost like a rollercoaster going over edge of a crest at the start of its run. There is no suggestion in the report that the pilots intentionally dropped 22,500ft. This drop is significantly greater and also more rapid than the 6,000ft drop over about 3 minutes being reported for the Singapore Airlines flight.
There is also a correlation between the altitude trace and the low frequency trend of the measured vertical accelerations, but I haven't attempted to integrate altitude variations to try to derive expected vertical accelerations. I didn't notice any discussion in the report about where the flight data recorder was positioned in the Boeing 720-B, but I assume it was somewhere in the tail and so would have also measured a component of pitch motion induced vertical accelerations, not only vertical accelerations at the aircraft CG.
The report noted a consistent pattern of test pilots making inappropriate pitch control movements on encountering of negative vertical accelerations. I haven't read the report in further detail to understand the basis of this observation, but I wonder if this trend remains with modern airliners if flown 'manually'?
Last edited by helispotter; 24th May 2024 at 12:26.
I hope the accident report for this case will look at whether the injuries relate to people who were not belted up? Even if seated and belted up, injury could still also occur due to flying objects including other people being thrown around the cabin.
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The FR24 Blog reports:
also in the same report:
They make it clear that the event happened and, a few minutes later, they made the divert. None of the media are going to even notice that information.
After processing the high-frequency ADS-B data for SQ321 and correlating the possible event time with media reports, we believe the turbulence event occurred at 07:49 UTC. In normal flight, some small variation in vertical rate is expected, however, at 07:49:24Z.824 the first ADS-B frame with an increased vertical rate is received by our network. There are unexpected changes to the vertical rate for nearly one minute before returning to 0 feet per minute.
Some media reports have erroneously reported the pilots’ initial descent toward Bangkok from 37,000 feet to 31,000 feet as the turbulence event. While the aircraft may have continued to experience turbulence during that descent, it was a standard descent to a new flight level controlled by altitude selection in the aircraft’s autopilot.
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Whilst i agree that in turbulence the aircraft will move up and down etc much of this is probably caused by sudden increases/decreases in the list available due to the massive increase/decrease in the ambient air pressure making the systems also think it has climbed/descended by significant amounts when it is probably just a few hundred feet at most. Even a few hundred feet though in the small amount of time is enough to cause significant injuries if you dont have your belts fastened.
Hopefully this incident will be a lesson to those that think they are invincible and dont leave their belts fastened.
Hopefully this incident will be a lesson to those that think they are invincible and dont leave their belts fastened.
But what many righteous posters seem to conveniently ignore is that when sudden and severe turbulence hits as the cabin crew are walking about and possibly pushing catering trolleys around, your seat belt will not protect you from having an F/A and her trolley crash down on you. There's also lots of other items potentially flying around. Once again, to avoid any misunderstanding, I fully support and personally adhere to the 'keep your seat belt on' policy. What I am saying is that it will not necessarily save you from light or even severe injury in a significant and unexpected upset.
Whilst i agree that in turbulence the aircraft will move up and down etc much of this is probably caused by sudden increases/decreases in the list available due to the massive increase/decrease in the ambient air pressure making the systems also think it has climbed/descended by significant amounts when it is probably just a few hundred feet at most
The report noted a consistent pattern of test pilots making inappropriate pitch control movements on encountering of negative vertical accelerations. I haven't read the report in further detail to understand the basis of this observation, but I wonder if this trend remains with modern airliners if flown 'manually'?
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