aircraft evacuation – FIRE, EVACUATION AND CROWD SAFETY BLOG http://fseg.gre.ac.uk/blog Fri, 23 May 2014 10:11:29 +0000 en-US hourly 1 https://wordpress.org/?v=4.8.2 Aviation Accident Survival Rates — Lies, Damn Lies and Statistics http://fseg.gre.ac.uk/blog/?p=357 http://fseg.gre.ac.uk/blog/?p=357#respond Mon, 26 Aug 2013 16:00:49 +0000 http://fseg.gre.ac.uk/blog/?p=357 Continue reading ]]> USA Today recently published (9th August 2013) an interesting story by Mr Gary Stroller concerning commercial aviation accident survival statistics.   You can find the story on their web site at:

http://www.usatoday.com/story/news/nation/2013/08/08/airplane-crash-survival-rates/2631567/

I think this is an interesting line of inquiry, but I don’t believe that the analysis presented addresses the whole picture and so can be misleading.  The main point of the story is made in the opening sentences of the article, namely:

 “More passengers are surviving fatal airline accidents during landing, but survival rates during stages of flight when most accidents happen have not improved from decades ago, a new USA TODAY study shows.”

 I am quoted in the article as follows,

“Edwin Galea, a professor at the University of Greenwich in England who is an aircraft evacuation expert, said the USA TODAY study is “interesting” but omits some serious accidents without fatalities.”

However, this is only part of the concerns I conveyed to Mr Stroller.  I have undertaken quite a bit of research on evacuation from aircraft including analysis of past accidents and appreciate how difficult it is to come to any meaningful conclusions when analysing aviation survival statistics (see publication list).  While I do not doubt the accuracy of the data presented in the article, I believe that the analysis is potentially misleading.  You have to look at the questions being asked, not just the answers being presented.  I do not think the questions that are being posed in the article are quite right.  My quotation in the article covers just one of my two main concerns.  These are:

1)      The USA Today analysis covers aircraft in which at least one person has died.  So the analysis definitely includes what could be considered to be serious accidents.  However, this is just a sub-set of serious accidents as it does it does not include serious accidents in which no one died, take for example just three recent accidents:

  1. US Flight 1549 on 15 Jan 2009, an A320 out of LaGuardia heading to Seattle, carrying 150 pax and 5 crew.  Aircraft was written-off after a forced landing on the Hudson River, there were five injuries, two of which were serious, yet everyone survived.
  2. BA Flight 38 on 17 Jan 2008, a B777 coming in to land at Heathrow, carrying 136 paxs and 16 crew.  Aircraft was written-off, there were 47 injuries, one of which was serious, yet everyone survived.
  3. Air France Flight 358 on 2 Aug 2005, an A340 coming into land at Toronto, carrying 309 paxs and 12 crew.  There was a serious fire and the aircraft was written-off, there were 12 injuries, yet everyone survived.

By anyone’s reckoning, these were three very serious accidents — so much so that in each case the aircraft was written-off – yet no one died.   The USA Today analysis simply ignores these type of incidents and so incorporates a bias in the data.

2)      The USA Today analysis includes accidents in which everyone on board died.  Thus the analysis includes technically non-survivable accidents.  These are accidents in which, given that the incident occurs, no feasible technological development is likely to improve the chances of survival as the trauma associated with the accident is simply too severe, for example:

  1. Mid-air explosion — Pan Am Flight 103 (Lockerbie), 21 Dec 1988, B747, all 243 paxs and 16 crew killed.
  2. Uncontrolled Flight into Terrain — Swiss Air Flight 111, 2 Sept 1998, MD11, all 215 pax and 14 crew killed.

The industry addresses these type of problems by introducing technological or procedural improvements to prevent them from occurring in the first place — prevention rather than mitigation.  The issue here is reducing the frequency of these events from happening in the first place.

Mixing technically survivable and non-survivable accidents into the discussion on survivability in aviation accidents confuses the issue as advances in technology are not likely to impact survivability in non-survivable accidents.  A clearer understanding of whether or not we are improving survivability in aviation incidents would be derived by splitting the discussion into two parts:

i)        First, consider survivability in technically survivable accidents.  The purpose of this investigation is to establish whether or not your chances of surviving a survivable crash is getting better or worse as a result of the advances in technology and regulation.  Related to this would be determining how likely you are to be involved in a survivable crash and whether or not this is improving.

ii)      Secondly, consider the frequency of technically non-survivable accidents.  The purpose of this investigation is to establish how likely you are to be involved in a non-survivable crash and whether or not advances in technology and regulation are improving these chances.

It is essential to filter the raw aviation accident data in an appropriate and meaningful way if truly meaningful conclusions are to be drawn as to the current state of aviation safety and whether or not it is improving.

PUBLICATIONS RELATED TO AVIATION ACCIDENT ANALYSIS:

1)       “Aircraft Accident Statistics and Knowledge Database: Analyzing Passenger Behaviour in Aviation Accidents.”, E.R.Galea, K.M.Finney, A.J.P.Dixon, A.Siddiqui and D.P.Cooney. AIAA Journal of Aircraft, Vol 43, Number 5, pp 1272-1281, 2006.

2)      “An analysis of exit availability, exit usage and passenger exit selection behaviour exhibited during actual aviation accidents.”, E.R.Galea, K.M.Finney, A.J.P.Dixon, A.Siddiqui and D.P.Cooney. The Aeronautical Journal of the Royal Aeronautical Society, Vol 110, Number 1106, pp 239-248, 2006

3)       “An analysis of the passenger to cabin crew ratio and exit reliability based on past survivable aviation accidents.”, E.R.Galea, K.M.Finney, A.J.P.Dixon, A.Siddiqui and D.P.Cooney. Human Factors and Aerospace Safety, Ashgate publishing, 5(3), pp 239-256, 2005.

4)      “An Analysis of human behaviour during aircraft evacuation situations using the AASK V3.0 database.”. Galea E.R., Finney, K.M., Dixon, A.J.P., Siddiqui A., and Cooney D.P. The Aeronautical Journal, Vol 107, Number 1070, pp 219-231, 2003.

5)       A Database to Record Human Experience of Evacuation in Aviation Accidents.  The Aircraft Statistics and Knowledge Database (AASK). Authors: E R Galea, K M Finney, A J P Dixon, A Siddiqui and D P Cooney.ISBN 9780117908390, CAA PAPER 2006/01. June 2008.

http://www.caa.co.uk/application.aspx?catid=33&pagetype=65&appid=11&mode=detail&id=3176

6)       The AASK Database: Aircraft Accident Statistics and Knowledge. Authors: E R Galea, D Cooney, A Dixon, K Finney and A Siddiqui. UK CAA Paper 2002/3 ISBN 0 86039 803 X, 2002.

 

]]>
http://fseg.gre.ac.uk/blog/?feed=rss2&p=357 0
Passenger Airline Safety Briefing http://fseg.gre.ac.uk/blog/?p=271 http://fseg.gre.ac.uk/blog/?p=271#respond Tue, 13 Nov 2012 08:52:22 +0000 http://fseg.gre.ac.uk/blog/?p=271 Continue reading ]]> Getting passengers to pay attention and understand the airline safety briefing is always a struggle.   I think that the most important information currently conveyed to passengers concerns the brace position, emergency lighting and the location of the exits.  Some information not provided during the briefing is that not all the exits on your aircraft are necessarily the same size.  On aircraft such as the B737 and A320, it is also important to understand that not all the exits are the same size – the ones in the middle are small and so it will take you longer to get out using these exits.

Part of the problem is getting the passengers engaged enough in the safety briefing so that they pay attention and potentially learn something that could save their lives in the event of an accident.  

Shown here are two safety briefings from the same airline, Air New Zealand.  Both are a little different from your ordinary in-flight briefing.  Both try and capture your attention in the hope that you will engage in the safety messaging.

(a) https://www.youtube.com/watch?feature=endscreen&v=7-Mq9HAE62Y&NR=1

AND

(b) https://www.youtube.com/watch?feature=player_embedded&v=cBlRbrB_Gnc

Which of these two videos do you think is the most entertaining?

Which of these two videos do you is the most engaging?

Were you distracted from the safety message by any feature of the videos?

Which of these two videos do you think is the most effective in conveying the safety messages? 

Let me know what you think, post a comment.

]]>
http://fseg.gre.ac.uk/blog/?feed=rss2&p=271 0
Panic, what Panic? http://fseg.gre.ac.uk/blog/?p=252 http://fseg.gre.ac.uk/blog/?p=252#respond Sat, 20 Oct 2012 16:55:35 +0000 http://fseg.gre.ac.uk/blog/?p=252 Continue reading ]]> On 19 Oct 2012 a B737 operated by Jet2 was on its take off roll when smoke was detected in the cabin.  The Captain brought the aircraft to a quick stop and all 189 passengers evacuated the aircraft.  I am guessing that the aircraft also had six crew who also evacuated.  Some 17 passengers were reported to be injured during the evacuation, four of which were being treated in hospital.

 The BBC headline on their website for this story states,

 Glasgow Airport evacuation: Passenger tells of panic on Jet2 plane

 http://www.bbc.co.uk/news/uk-scotland-20001291

Is this a fair account of the situation on board the Jet2 aircraft?  Were people really behaving irrationally and in a selfish manner during this evacuation?  Had social norms broken down, was it everyone for themselves?  Or is this just another media exaggeration to sensationalise a story?

Other media accounts had more factual headlines, such as from the Express web site:

17 Injured as plane is evacuated at Glasgow Airport after smoke alert.

http://www.express.co.uk/posts/view/353053/17-injured-as-plane-is-evacuated-at-Glasgow-Airport-after-smoke-alert

From the Telegraph web site we have:

Glasgow Airport Seventeen injured as aircraft aborts take off

http://www.telegraph.co.uk/news/aviation/9619600/Glasgow-Airport-Seventeen-injured-as-aircraft-aborts-take-off.html

From the Mail Online web site we have:

20 crew and passengers are INJURED in emergency evacuation by inflatable slides from jet at Glasgow airport after “engine” fills cabin with smoke.

http://www.dailymail.co.uk/news/article-2220041/17-injured-crew-passengers-evacuated-plane-Glasgow-Airport.html?ITO=1490

Evacuating an aircraft is not something that people do every day, and so it is going to be an unusual experience for most people, and a frightening experience for most, especially if you believe, as these people must have, that a fire had started on board.  All 189 passengers will also have to exit the aircraft in an awful hurry and in an unusual and physical manner i.e. jumping onto slides or climbing out of the overwing exit, onto the wing and then jump to the ground.  The cabin crew will have been yelling at the passengers to evacuate, leave your bags, jump onto the slide, while the cabin was filling with acrid smoke.  The passengers on board would have been a mix of people including;  men, women, children, the elderly, family groups and possibly disabled people.  They would have had a range of flying experience from frequent flyers to the ocassional  flyer.  Given this mix of people we would not expect everyone to react in the same way, and not everyone will react without emotion.  But will panic really break out in this situation, will it be everyone for themselves, as the BBC headline suggests?

The opening sentence of the BBC article may give this impression,

 “Passengers on an Alicante-bound plane from Glasgow Airport have described “sheer panic” after “swirling” smoke in the cabin forced an emergency stop.” 

So what do the BBC base this on?  A quote from one passenger was reported as,

“… passenger X said “people started running” as the pilot of the Jet2 737 shouted “get out, get out” following the emergency stop at 07:40.”….”

Well this seems quite normal given the situation, who wouldn’t be trying to run out of an aircraft filling with smoke with the captain and cabin crew yelling at you to get out!  Indeed, you would be in a panicked state if you just froze on the spot and didn’t do anything — this is called negative panic or behavioural inaction.  It is a normal behaviour to try and get out of the aircraft as quickly as possible, especially if the captain and cabin crew are yelling at you to get out!

The BBC inform us that one passenger was travelling with his young family and report the passenger as saying, 

 “I have a nine-week-old daughter and a four-year-old daughter. I had my nine-week-old attached to my chest as I went down the emergency chute and my wife had our four-year-old and was in tears. ……. It was just sheer panic, something no-one would want to go through again.”

Clearly this situation is extremely frightening and traumatic, especially if you have a wife, child and infant to look after, make your way to the emergency exit and then jump onto a slide — all while the other 185 passengers are trying to get out and the aircraft is filling with smoke.  It is not surprising that there were tears and it is not surprising that they would have been extremely anxious and would have had adrenaline pumping.  But the behaviour of this family does not sound like a panic behaviour.  They kept together and assisted each other out of the aircraft.  Their behaviour sounds like a rational response to the extra ordinary situation that they found themselves in.  While the passenger uses the “P” word in his description it would have been helpful had the journalist gone on to ask the passenger to describe the scenes of panic that he reported.  Often people will use the “P” word to describe people running away from danger, or people crying.  This does not indicate that people were behaving in an irrational manner or that social norms are ignored.

The BBC also selectively quote another passenger’s account in their article and also helpfully include a recording of the interview.  In the article the passenger is reported as saying,

“I was sitting in row 11 and I could smell smoke as we were accelerating hard. “I looked up. One or two passengers, including myself, had our reading light on and when I looked up to the lamps and the ceiling, I could actually see smoke swirling around and I thought, oops, there’s something not right here.  “We were accelerating very, very hard down the runway at this stage and I was about to scream out to the cabin crew when obviously the pilot realised there was something wrong and he immediately throttled the engines back and put the brakes on. “It’s the hardest braking I’ve ever experienced in my life.” 

This is where the BBC article leaves the interview.  This selective quotation fits into the tone of the story that is being told by the journalist, smoke filling the aircraft and the dramatic stop.  However, in the recorded interview, which is also available on the BBC website, the passenger goes on to say, but is not quoted in the article,

“….a few seconds later he gave the order to evacuate. Everybody got out of their seats, one or two passengers tried to reach into the overhead lockers to get their baggage but they were politely told in no uncertain Glaswegian terms just get out of the aircraft” both the journalist and the passenger laugh, “leave your bags and get out, but there was no panic”.

The passenger is describing an orderly behaviour and makes the observation that there was no panic.  This unfortunately does not fit into the tone of the article and so is not reported.  The journalist desperately tries to get back to possible stories of panic and extreme behaviour and goes onto to say,

“You are laughing about it now but that is probably not what you were feeling about it at the time.”

 The passenger (helpfully) responds,

 “..There was smoke coming off the right hand engine so I was going out the left overwing exit….we all wanted to get off as quickly as possible but it was all orderly, there was no panic.”

In describing his own behaviour the passenger paints a picture of rational behaviour, a clear thought process that lead him to select an appropriate exit.  He also describes the behaviour of others as being orderly and states that there was no panic.  Clearly this account does not fit with the tone of the article so it is not reported.  The journalist rather go with the easy story, the story that is going to make a sensationalist headline, the story that is in-line with the publics hollywood feed expectations when it comes to evacuation stories — people panic!

While these two accounts are not sufficient to base a judgement on the nature of the evacuation from the Jet2 aircraft, they certainly do not support the BBC headline or the tone of the BBC story.  I am sure that there were people screaming and crying during the evacuation, but this in itself is not an indication of panic behaviour.  Indeed, the accounts in the BBC story support the understanding built up over the past 30+ years that on the whole people do not tend to panic in emergency situations.  Indeed, quite the opposite, people tend to behave in a rational way and social norms are maintained even in the most extreme situations.

Unfortunately, this story simply perpetuates the myth that in emergency situations the norm is for people to panic.  I think that a more interesting, uplifting story is that in emergency situations people tend not to panic, but tend to behave in a rational supportive manner and are more likely to assist others then selfishly think only of themselves.

The Jet2 aircraft after the evacuation (picture from ITV website)

 

 

]]>
http://fseg.gre.ac.uk/blog/?feed=rss2&p=252 0