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Severe turbulence LHR-SIN. One dead.

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Severe turbulence LHR-SIN. One dead.

Old 21st May 2024, 16:33
  #81 (permalink)  
 
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Originally Posted by Widger
I am a little bit staggered but not surprised at the comments by some on here in climate change denial. Whilst in your short flying history you may not have noticed a big change, if you research over a few decades, you will see it. This is a report from the scientific experts, showing that Turbulence has increased including clear air turbulence.

Aviation turbulence soared by up to 55% as the world warmed Ė new research - Connecting Research (reading.ac.uk)
I am a little bit staggered but not surprised at the comments by you on here peddling the climate change scam.

If you had bothered to read the report that you quote, you'd have discovered that there has been no increase in observed turbulence, only modelled turbulence which is about a reliable as modelled infection rates...

The NTSB keeps records of accident events where turbulence is reported and it shows no statistically significant increase. If the outlandish claims of a 55% increase in CAT made in the Reading University report were true then we wouldn't be looking at an essentially flat graph.
According to the NTSB, the majority of injuries occur below 20,000 feet in the vicinity of thunderstorms.


Turbulence and non-turbulence-related Part 121 accidents in the U.S. from 1989 to 2018. U.S. National Transportation Safety Board.


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Old 21st May 2024, 16:38
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Originally Posted by Andy_S
Interested SLF rather than professional here......

I assume that the diversion into Bangkok was based on this event being a medical emergency rather than any danger to the aircraft itself. I have read nothing, nor seen any professionally informed comment to the effect that the structural integrity of the airframe is likely to have been compromised.
I stand to be corrected, but I have no recollection of any civil airliner having been written off due to flying through turbulence.
In the beginning the Wright blothers took a stab at how strong they thought the wing attachments should be. As time has progressed many aircraft, military & civil, have been lost due to unforseen wing loadings. As time has past we became wiser about the sort of forces you need to plan for. That learning process does not stop here. With probable airframe damage, diverting to the nearest suitable airfield was the most prudent course of action. Peril = Risk x Time No point in prolonging your exposure to a possible airframe breakup.

Given the severity of injuries, the welfare of the pax also demands prompt medical assistance. So you have two pressing reasons to get on the ground ASAP
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Old 21st May 2024, 16:43
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Similar to BA a few months ago SIN - LHR which made an ATB due to injured pax.

The Daily Mirror are emphasizing that it's a "Boeing" aircraft involved.

One report states that the seat belt sign was turned on moments before the encounter which suggests weather, rather than CAT which would have no advance warning.

The B777 doesn't have a history of flight control system problems so not a likely cause. An aircraft of this size probably wouldn't be that badly affected by wake turbulence, even from an A380.

The Bay of Bengal has some nasty weather at times, which doesn't show up very well on the radar unless you've got the gain cranked up to max. I'm thinking a weather encounter which only became apparent at the last minute, too late to divert around or prepare the cabin.
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Old 21st May 2024, 16:46
  #84 (permalink)  
 
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FR24 has released some granular data that includes the 60 seconds or so that the turbulence event lasted. There are 20 or so data points within that period, and the usual caveat re ADS-B VRate applies, so caution is still necessary when trying to resolve any accurate g values.
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Old 21st May 2024, 16:52
  #85 (permalink)  
 
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Originally Posted by Claybird
Well, why don't you finish what you started. Who deviated from the flight plan there? Let's get it out... come on

And more importantly, the safety protocols that were put in place after that
Yes, there were some "circumstances" that may have contributed to the likelihood of an accident (which are mentioned in the Wiki article that others have now linked), but the question was about whether there has ever been an aircraft total loss due to CAT.

This was the first one I thought of as I have a friend who was BOAC cabin crew at the time and knew people who were lost.
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Old 21st May 2024, 16:52
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Dear God. Seatbelts - WE KNOW! Most people now wear seat belts loosely fastened but you have to move around the cabin from time to time - the crew do it all the time. When known turbulent conditions are being flown into we are warned and the sign comes on. In the millions of hours flown, how many people have been killed because of turbulence? I haven't heard of any - but I'm sure some fingerwagger knows different. This instance is being reported as a heart attack. Life is full of hidden dangers but being killed because of turbulence is WAY down on the list.
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Old 21st May 2024, 17:04
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Just read about BOAC 911, horrible crash. The day before on 4th March there was a crash of Canadian pacific flight 402 on approach to Haneda with only 8 survivors. Few of the survivors decided to take next flight in the morning which happended to be BOAC 911. Its like a plot to a Final Destination series.
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Old 21st May 2024, 17:06
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Any progress on CAT indication kit? Some has been developed but I have no experience of it; anyone?
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Old 21st May 2024, 17:12
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Originally Posted by Wycombe
Yes, there were some "circumstances" that may have contributed to the likelihood of an accident (which are mentioned in the Wiki article that others have now linked), but the question was about whether there has ever been an aircraft total loss due to CAT.

This was the first one I thought of as I have a friend who was BOAC cabin crew at the time and knew people who were lost.
Yes, you are correct. Sad story and a sad period, but that era was touch and go in aviation, indeed I would venture to say up to the late 80s. But these accidents paved the way for today's safety
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Old 21st May 2024, 17:27
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Just watched the BBC News - sensationalist report: "it dropped 6,000 feet". It did not... it descened to FL310 to clearer air (it appears) at an albeit sporty 2,000fpm. I guess this is in an area where severe conditions aren't exactly unexpected... to be honest, it's an area as a passenger I don't plan to sleep as it's often disrupted. Wasn't there a similar A380 incident a few years ago in a similar area (I think QF?)

On the ITCZ point - it is very normal. I'm curious as to the in-flight conditions though, because despite the severity of some cells, they dont exactly move quickly, so it's not particularly difficult to go around them? Assuming this is more of a CAT event than anything else. They dump their load and dissipate. So in broad daylight, I can't imagine such weather would've unnecessarily been unexpected. No PIREPS on the radio also? (I'd be pretty certain this is an airway well travelled into SE Asia.
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Old 21st May 2024, 17:41
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Shall I start by saying that alt the SLF commenting on here is not helping!

Weather across Bay of Bengal / Andaman sea - yes itís usual and something that airline pilots fly through everyday of the dyesr, both by day and night (yes when itís dark!) Nothing new
Singapore pilots - based in Singapore, used to this weather every time they fly, many airlines fly these routes! Nothing new
Descent - 6000ft at 1000-1500ft/ minute is what big aircraft descend at usually ( they can do it a lot quicker) Nothing new
Passengers. No seat belts - lots of SLF know better and take seat belts off once airborne, totally disregarding the seat belt signs. nothing new!
Seat belts on a long time - could be for weather, could be for aipotential turbulence from aircraft ahead, pilots could have forgotten Nothing new!
Diversion - with injured people, of course. Nothing new.

Take no notice of Sky sensationalism!
let the authorities look into it,
And yes I do know what Iím talking about, flown big jets around the world for more years than I care to remember, and still flying them now, flown across this area countless times, nothing new!


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Old 21st May 2024, 17:43
  #92 (permalink)  
 
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Widger, a most valuable contribution #51 - climate change.

Many pilots with longer career spans could reflect on changes that they have seen, the effects are real.
These changes will challenge operators and regulators, and also manufacturers who have to consider future design requirements, operations, and customer requests for a smooth ride.

The circumstances of this incident are unclear, but from weather chart at the time, c.b. activity, either rapid buildup, not seen, or misjudged could generate the surprise and severity which has been reported.
Whilst alternatives should not be dismissed, it is less likely that CAT, cruise level severe 'chop', up/down draughts were involved based on current reports.

Climate changes affecting c.b. have been noted;- storm size, laterally and vertically, ice crystal icing (large storms), and speed of buildup.

Storms require respect, more-so in modern times. The industry needs to consider a larger recommended miss distances, and examine the use and potential dependence of 'automated' wxr systems.

P.S. as higher performance modern aircraft have capability of overflying storms cells there will be new challenges and surprises. Experience strongly suggests not to overfly any storm.
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Old 21st May 2024, 18:09
  #93 (permalink)  
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FR24 data suggests SQ321 climbed from FL370 before the 'drop'. On passenger described a sudden nose-up climb. Could the flight crew have tried to get above weather at the last moment, but left it too late?
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Old 21st May 2024, 18:15
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Originally Posted by Pif Paf
Shall I start by saying that alt the SLF commenting on here is not helping!

Weather across Bay of Bengal / Andaman sea - yes itís usual and something that airline pilots fly through everyday of the dyesr, both by day and night (yes when itís dark!) Nothing new
Singapore pilots - based in Singapore, used to this weather every time they fly, many airlines fly these routes! Nothing new
Descent - 6000ft at 1000-1500ft/ minute is what big aircraft descend at usually ( they can do it a lot quicker) Nothing new
Passengers. No seat belts - lots of SLF know better and take seat belts off once airborne, totally disregarding the seat belt signs. nothing new!
Seat belts on a long time - could be for weather, could be for aipotential turbulence from aircraft ahead, pilots could have forgotten Nothing new!
Diversion - with injured people, of course. Nothing new.

Take no notice of Sky sensationalism!
let the authorities look into it,
And yes I do know what Iím talking about, flown big jets around the world for more years than I care to remember, and still flying them now, flown across this area countless times, nothing new!
Probably one of the most sensible posts on this thread.
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Old 21st May 2024, 18:32
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Former flight attendant here, used to laung-haul between Europe and far far East. This is a really terrible incident!
Our main worry during severe turbulence was carts that are not secured in the galley, with all latches down. If a fully loaded cart flies up and down on PAX - well that can be 90kg of hard metal in motion!
So most injuries will happen due to loose objects flying around (including smaller items, PAX' laptops, bags etc).
Cabin crew are expected to perform some duties when PAX are sitting and seat-belt sign is on but only if it is light turbulence. We are trained to grab ANY vacant seat the minute the pilot requests crew to be seated, so that might be the closest passenger seat because our jumpseat is too far. Also, we are trained to respond to a "all crew be seated" announcement instantly. There is only a dozen of us to scramble. But to get 250+ pax to sit and fasten seatbelts can take a long time and effort. So first safety of the PAX, then us.

Hot drinks or any service would definitely be stopped during such an event. That said, you ARE subject to the mood of the air and there is always a small risk. As an example, after a duty flight from Japan to France, I deadheaded on an Air France to my home airport.
The flight attendant served me a boiling hot coffe, the pilot did a strong left-right-centre roll and that coffee lifted into the air and dropped into my lap. Imagine a uniformed girl jumping up in her seat and swearing loudly. That's how bad the burn was. Air France crew couldn't care less. Haha.
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Old 21st May 2024, 18:43
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Originally Posted by MichaelOLearyGenius
I don’t know the full details but it’s time to make it a legal requirement to wear a seatbelt while seated on an aeroplane just like it is in cars.
Originally Posted by ZFT
I doubt many will argue with that but enforcement will be a headache for the cabin crews.
Surely there is a simple electronic solution with 2 very simple sensors.

If the seat is occupied, is the belt fastened ?

This would only need a couple of sensors, plus the additional wiring, logic and associated display(s).

Is this already implemented on some aircraft ?

Last edited by kit344; 21st May 2024 at 18:46. Reason: Added a couple of words.
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Old 21st May 2024, 19:16
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Originally Posted by kit344
Surely there is a simple electronic solution with 2 very simple sensors.

If the seat is occupied, is the belt fastened ?

This would only need a couple of sensors, plus the additional wiring, logic and associated display(s).

Is this already implemented on some aircraft ?
How does this proposed system detect that the belt is round the person in the seat?
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Old 21st May 2024, 19:36
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Originally Posted by Magplug
With probable airframe damage, diverting to the nearest suitable airfield was the most prudent course of action. Peril = Risk x Time No point in prolonging your exposure to a possible airframe breakup.
So any incidence of "severe" turbulence necessitates an immediate landing?

Seriously??

Originally Posted by Tailwind64
A pitch nose up just before the seat belt signs went on.... stall waning probably activated. Crew had time to react. The loud thump as a superstall happened.
This was not turbulence.
This thread is nothing if not entertaining........
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Old 21st May 2024, 19:44
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Reference passenger attitudes to the seat belt sign it's worth noting that certain operators have a protocol of switching the seat belts signs on when a flight deck crew member needs to leave the flight deck for a personal comfort break and the seat belt sign remains on until that crew member is back on the flight deck.
There are of course reasons for doing this to ensure the security of the flightdeck but when the signs go on for this purpose they are not being switched on for turbulence. Rather like crying wolf when it happens too often for non turbulence reasons then some passengers might get the impression that it's not that important when the signs are genuinely switched on for turbulence.
There was an earlier comment in this thread about large transport aircraft breaking up in severe turbulence and how rare this is. I may be wrong but was always under the impression that when mid air break up have occurred it's more a case of the pilot mismanaging the aircraft in the turbulence (I'm not implying that managing an aircraft in severe turbulence is easy) rather than anything intrinsically wrong with the aircraft.
From memory I recall the BOAC 707 which broke up near Mt Fuji went to something like 5.5g before things started to break. We should also keep in mind that in those days a lot less was known about rotor streaming downwind of high ground.
Also interesting to mention is that this was before the days of flight data recorders but an 8mm movie camera was recovered in the wreckage from a passenger who was taking pictures when the turbulence was encountered and the aircraft started breaking up. When the film was developed it was noticed that the frames started jumping. They got an identical camera and put it in one of those "G" simulators and when it got to about 5.5g it started jumping frames. From this they deduced the G loading on the aircraft of around 5.5g
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Old 21st May 2024, 20:26
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I fly this route regularly; and have done for 25+ years.
My experience is that it's way more difficult to find a path through the storms than in the past.
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