June 26, 2020, ©. Leeham News: In our Corner series about flying during the COVID-19 pandemic, we look closer at the boarding and deboarding part.
We have identified it as possibly the most troublesome part of a flight during the COVID pandemic. We look at the findings from simulations by boarding/deboarding experts.
When one looks at the whole chain of events for a commercial flight and combines it with recent research into the primary virus contamination process (via the exhaled breath of an infectious person), the boarding and deboarding processes have the most unpredictable and troublesome face to face moments.
A report from an experienced boarding simulation team is in final review and will publish in the coming days. The report is produced by Dr. Michael Schultz, Institute of Logistics and Aviation, Dresden University of Technology, and Dr. Jörg Fuchte, Diehl Aviation.
There is considerable knowledge around simulations of airliner boarding and deboarding. Target has then been how different schemes (random, least row first, etc.) affect the efficiency of the process.
Now the target is minimizing the instances and time passengers spend in close proximity, waiting for bags to be put in bins and passengers to find their place.
By adding a virus transmission model to well-known boarding and deboarding simulation tools, the chance of a contagious person infecting others can be simulated.
The report analyzes different boarding strategies, with each strategy simulated 125,000 times to cover individually different behaviors, passengers entering the aircraft at slightly different times, or changes in the entry sequence.
The result is a statistically relevant analysis of the number of critical contacts caused by different boarding strategies.
Figure 2 shows a results table from the report. The avg. row shows the average number of additional possible infections followed by RSD, which stands for Relative Standard Deviation (a measure of the amount of variation of the result in correlation to the average value).
The conclusions from the simulations are:
“The standard random boarding without additional distances and normal carry-on luggage results in about 5-6 critical contacts between passengers.
Changing the boarding procedure reduces the number of contacts by more than half. Introducing a distancing of 1.6 m reduces the number of critical contacts for the random boarding to about 1-2. Hence, distancing alone does not eliminate these contacts.
Carry-on luggage influences the time spent in the aisle at a high physical workload (with high breathing). Reducing the luggage by 50% reduces the number of critical contacts to about 1 for the random boarding.
Boarding procedures like outside-in or reverse pyramid have a profound effect and reduce the number of critical contacts substantially below 1, even with normal carry-on luggage.
In the context of COVID-19, the question arises, how these contacts will be critical in terms of transmission probability. The authors derived a transmission risk model and evaluated the individual passenger contacts. Here, they find that back to front procedures will provide less transmission risk than random boarding but at the costs of higher boarding times.
The use of the rear door will reduce the transmission probability significantly for all boarding strategies.
The transmission probability during deboarding is hard to influence since physical distancing is difficult, if not impossible, to impose. The number of contacts and the transmission probability remain at a high level, which indicates deboarding as the critical process in the aircraft cabin.
To reduce the transmission probability, the timing of passengers entering the deboarding would need to be controlled.”
Airlines should focus their COVID-19 work on the boarding and deboarding procedures. Stowing of hand luggage is a major cause of critical contacts. Reduction schemes like letting it be stowed in the cargo bay in exchange for a perk shall be a focus.
In addition, boarding schemes like outside-in are effective.
The most critical moment is deboarding, where passengers are standing face to face in the aisle for a long time, waiting for the aisle to clear for deboarding, Figure 1. A scheme where passengers remain seated until the rows ahead move would help a lot.
There is presently no initiatives around deboarding to our knowledge. It would be an area where the airlines could achieve significant improvement in lowering infection risks.
My friend Mentourpilot has flown as a passenger the trip Barcelona-Frankfurt-Stockholm with his family on Lufthansa in the week. He gives a good view of flying in Europe just days after the partial opening:
Using all aircraft doors and letting pax know which one to use for boarding and deboarding printed on their boarding passes would help. Airlines can let only window seat pax boarding first and last have carry on luggage and thus charge for it.
Thanks again Bjorn. The de-boarding and carry-on problems seem solvable by the same organization process as used for boarding. As Claes mentioned above, the risk can be lowered further by using multiple doors.
Personally I never get up and stand in the aisle anyway, unless I have to make a tight connecting flight. I’ve always wondered why connecting passengers couldn’t be de-boarded first. Maybe that could happen now.
These solutions seem to be a matter of educating travelers. I would think cooperation rates would be high if people understand their health is being protected.
Good laugh, when you see people grabbing their luggage when the aircraft crashes (somewhat intact) then you can be sure that education is the key.
Thanks, I needed that.
I was more inclined to the shock collar method, but then being a pragmatist I go with the evidence.
Hello Bjorn. I flew last week on US transcon flights. The aircraft was clean and crew wearing masks at all times. Passengers seemed compliant overall.
I didn’t feel there were major issues with the boarding process. The airline had relatively OK procedures to board passengers from the back after those in first-class and disabilities. Social distancing felt OK in that part of the flight.
However, all this good work was thrown away, in my opinion, by the de-boarding. It is natural for passengers to lose all discipline after seating 5+ hours. The airline did not have a specific de-boarding procedure. Most people were not respecting social distancing at that moment, being in a rush to exit the aircraft.
Airlines need to implement de-boarding procedures. For example, have all passengers seated in a row ending in 1 or 5 exit, then 2 or 6 etc…
People have no discipline (as a whole or group), its only when they are managed do they operate in a credible manner.
Otherwise their behavior is quite close to stampeding cattle.
You can get out of the way or be trampled but you don’t stand a chance with a herd (errr group) of people.
The cabin air stream from the top of the cabin downwards to bottom and via inlets goes through the Hepa filter which take out almost every particle. Cabin air is refreshed every 2-3 minutes.
Now realize cabin air is very turbulent, specially in packed cabins & the refreshment rate is only an average. Some air will hang around much longers. Specially at window seats & people fool around with the personal outlets. And passengers sit shoulder to shoulder more then ever before.
The article and CFD results show that air circulation velocities in the seating head-areas are on the order of 10 to 30 feet per minute. That supports the case of adequate airflow.
It’s true that there will always be turbulence and areas of recirculation. The goal is not to have perfectly uniform flow, but to have enough ventilation to prevent the transfer of significant viral load between passengers. When combined with masks, that should be possible.
The average resting respiration rate is 16 breaths per minute. If we take the low-end mean of 10 feet per minute velocity, that means an exhalation will migrate 6 to 8 inches downwards before the next breath.
Obviously it’s not perfect, but given that we now know that ventilated public transportation has a low risk, the enhanced level of ventilation in an aircraft should also keep the risk low.
Ventilated as opposed to un-ventilated public transportation ? Ventilated as shot full of holes?
Only study I know of is on aircraft.
Discussed in last week’s Corner. Studies have shown there are not clusters of infection associated with public transportation. Reason given is good ventilation, also frequent cycling of doors.
I think the communications going around on aircraft cabin airflows today need a closer look and more honesty.
It’s full of incorrect assumptions and suggestions steering public perception. Major league marketeers praticing perception management with half truths.
The directions of airflows mostly aren’t verticial downward at all & the refreshment rates only averages all cabin air combined.
The reality airlines stay away from communicating:
Here is an article about a database that tracks COVID clusters and their tracked sources from around the world. It’s notable that transport (of all kinds) ranks last among all cluster sources. That is consistent with Bjorn’s reasoning, and what has been observed thus far.
I’ve looked extensively for reporting on clusters that have resulted from airline travel. There is one paper quoted in many places, researching a flight from which several passengers subsequently tested positive. But the authors admit they do not know if the transmissions occurred on the flight.
There are also reports of clusters among flight attendants. But it appears the transmission was within that group rather than to-from passengers, for whom there were no clusters traced back to the airline.
Ultimately we should know more as travel resumes and there is more evidence available. But I think airflow circulation patterns in the cabin, even if they include areas of recirculation, do not by themselves indicate an elevated transmission risk. I suspect the large net displacement of stale air, & replacement with fresh air, would be a far greater factor in preventing transmission. That is effectively the protection factor present in outdoor settings as well.
Rob, we should avoid reasoning with the result set beforehand.
Your article shows large shared accommodations and ships are the major case cluster for COVID-19. Then you conclude those are not comparable to a full aircraft. Non-sense, the difference is that people are even much closer together and stuck like in a prison.
Aircraft weren’t flying, people are not allowed to travel and see, little infections in transport. So aircraft are safe!
We must be honest and professional to keep COVID under control, not take the public for a ride. Even if we work in the industry.
Keesje, please note the graphics show that ship instances were few in number, but each involved very large numbers of infected people (hundreds or thousands). Those people were stuck together in confined quarters, for weeks at a time with no possibility of exit.
Some were at the start of the pandemic, most were also without the masks and cleaning supplies and treatments that we know now are effective (as the US carrier captain was fired for making public). But that is very far removed from the current experience of air travel.
I agree that the airline data are limited, and that it’s possible for clusters to emerge as air travel rebuilds. We should be watching for that closely. But at least from the data we have now, that does not appear to be the case at present. I hope that as early adopters, who view the risk as manageable, begin to travel, we will get a better sense of the true risks.
I would be an early adopter, you would not be, and that is fine. Neither choice is wrong, and each person should be free to decide.
I would like to commend you for researching the issues and building a cogent argument for your position. Also for not employing ridicule in your arguments. Because of that, I think as the data build, you will eventually follow them, however they work out in the end.
One detail which a flight attendant couldn’t answer on a flight this week. Many passengers touch the air flow vent control after being seated. While the seats and armrests are wiped between flights, are the vents wiped down as well? They could be a transmission point so bring your own wipes before adjusting them.
Here is a link to a site which lists cleaning procedures for major US airlines. They mention overhead controls, and all surfaces that passengers may touch or operate.
Yep, that is going to work
Me thinks zip ties would do it though.
I agree with you – the sight of so much instant expertise is not convincing, sounds much more like ‘expert’ PR –
-yesterday every expert knew nothing got every aspect of virus prevention and preparation wrong, but now, almost instantly….they sound as if they think they are 100% correct
Treating airtravel as that which takes place within a plane, the most controllable public environment by far, sounds like an experiment, get this right and bingo! problem solved
Airtravel is airport and access to
The problem is with the 99,9999% of life which does not take place in the plane, and nothing hardly except the common sense stuff in this discussion is applicable to that
I suggest 600/800k maglev – oops- that’s also Chinese: but why not change with the times?
Gerrard, if you will kindly notice, Bjorn has made his presentation based on the knowledge and data that are currently available. So far at least, the trends are consistent and support his position. However it’s still early days and that could change as more data become available.
If you are correct in your assertions, that will show up in the data, which will refute what Bjorn has said here, and I’m sure his view will adjust accordingly to match, as would mine.
It’s not about claims of expertise or certainty, Bjorn has made neither. It’s about following the truth as it becomes apparent to us. The road to truth can have false branches, and we are as susceptible to those as anyone else, but they always become apparent in time. If they do this time, there will be no argument from us. We’d be wrong and we would say so.
I would contrast this to your arguments, which are heavily based on your certainty that you are right. So the things you accuse others of are in fact practiced by yourself.
We know there are large differences in risk associated with type of environment and activity. Those are not well established or understood yet, but an emerging trend is that indoor spaces with tight groupings of actively engaged people have the greater risk, while outdoor spaces with dispersed people and limited engagement, have the lower risk. That more or less follows common sense as well
So we can infer from that, at least for now, the properties of group interactions we want to emphasize, to lower our risk. The data show that transport does not have a high risk, and that is consistent with the properties noted above. Also air travel appears to have a low risk, which again is consistent.
It’s also clear that with this understanding, we can adjust our daily experiences further, to emphasize the properties that lower risk. This knowledge should improve over time, and either it will support the present trend or refute it. We need to be open to either outcome, but we should follow the data & trends, in whatever direction they lead.
This also has applications to other aspects of life. Some bars, restaurants, gyms, churches, etc are creating outdoor venues, and also looking at improving indoor ventilation and air quality. The days of “packing ’em in” may be over for awhile, but with adjustments, they can still survive. We’ll move forward by learning, not by believing that all efforts are hopeless.
You should not, please, accuse me of thinking I am right, or that I have ‘arguments’
About what can I think I am right, unless it is that I am certain it is impossible to be certain about this bug, and of the usefulness of ‘what if’
Bug Certainty is impossible, those health experts today are the very same who yesterday got it very badly wrong yet so certain yesterday and today
I do not suggest that Bjorn has made claims or does anything but report – you would not mistake him for a health expert, neither do I –
Can you list my assertions? I have re read my comments and find I have made none, although I do suggest maglev
The data as you call them, the facts, will not be ‘in’ in any definitive way for a long time, years at least
Meanwhile best to keep uncertainty as the key – and better still look at what might best replace the plane
What I have questioned are the double standards being adopted, and the levels of risk involved – whatever nasty this bug is it’s not ebola nasty
But it’s everywhere, and it’s cousins are coming soon, maybe this fall already : redesigning social life and infrastructure is not going to work, not only is this more than difficult it’s more than expensive
Plus the uncertainty, no definitive facts
Double uncertainty – the no way of knowing if, darn it..if the bug does’nt or won’t adapt faster than humans can, how about that…. 6 feet not enough, now we need 9…then 26…oh
All the bug needs as infrastructure is your body – you on the other hand require gigantic amounts of laborious difficult to modify this and that
I am fairly certain that high density society trying to mimic low density is guaranteed failure, and that very very simple living outdoors is slightly possible in the tropics but not hardly anywhere else, let alone car or phone factories
Assertions can also be negative, for example that something is not possible or has no value. Your assertion here is that no certainty is possible, therefore no learning is possible, therefore attempts at improvement must be fruitless, and analysis can be discarded.
That too would appear in the data, there would be no trends, and instead randomness. But that is not what we find.
I’d invite you to checkout the rt.live site. It shows the results of state’s efforts to control the effective transmission rate (Rt). Since states take different approaches, have different circumstances, and are at different points in the cycle, there is wide variation. But also something to be learned from the differences.
Some states have done well and shown that the rate can be held below unity (we see this in many EU countries as well). Some have achieved that but lost it again. There are differences in policy and compliance that are revealing and helpful.
But you have to start with the assumption that the information and analysis have value. If you don’t believe that, then it will be meaningless. Same with Bjorn’s analysis, or mine.
Really! Rob, ‘no certainty is possible therefore no learning is possible’ is what I assert?
You should learn to present a case without denigration and without such an obvious logical failure
It is only when certainty is absent that learning is possible, as certainty by definition precludes modification
Uncertainty instills caution and respect for a bug about which very little is known
Some states or nations have done ‘better’ than others, the physical condition and age of the inhabitants, pop density, the geographic, climatic, etc, the many variables which may weigh, plus sensible or less sensible gvmt measures – perhaps – as far as that goes
But so what? one merely arrives at the NZ paradox – no cases, no problem, except what about the rest of the world, all that has been achieved is a country in permanent quarantine
The rest of the world is not just tourists , it’s people who have developed antibodies or immunities such as those developed with/by repetitive exposure to influenza – that means they commute freely and are in more robust (note not better) health – NZ’ers are not, fall behind, and so are backwatered
Which means the ‘problem’ is merely moved – as I said with the plane, there’s no point is getting this solved if it is impossible to solve the problem in the rest of life : there’s no harm in better boarding or filters, but no lives are going to be saved
The problem is logistics I grant you – begin by recognising this bug has superior logistics, and is much more adaptable than you are, that means you must learn to live with it, not the other way round
Nor attempt to eradicate it – partly because you can not, mostly because you do not want to make the effort to eliminate the conditions of bug production, industrialised agriculture
If you discuss the means of production, the discussion quickly extends beyond filters and café seating and goes to the heart of the matter
Certainty is a built-up construct that progresses by degrees of confidence. It depends on certainty of the underlying premises as well, which are also built-up over time, and with evidence. Thus learning is dependent on the provenance of certainty. Without it, there is nothing to build upon.
You dismiss the New Zealand achievement as you do other things, but it gives them a baseline of zero, which they will work to preserve as they lift travel restrictions. They will be selective and have a right to be.
And I suspect they will continue to succeed, they will isolate and control any clusters that appear, so as to limit their exposure. But they will not isolate themselves, or withdraw from the world stage.
If you believe otherwise, you are entitled to that opinion, but I doubt people in New Zealand and elsewhere will share it.
“there’s no point is getting this solved if it is impossible to solve the problem in the rest of life”
This the crucial issue and is where we differ. I think there is a point, and that it is possible to solve the problems. So perhaps we should leave it there, as we are unlikely to agree.
You take the attitude of the technician, you tell yourself, if we can break this down into small parcels we can, one by one, come up with solutions
That means you do not have to think about the problem in it’s entirety and it’s context, in it’s causation, only in certain details of certain symptoms, manifestations, ‘the task in hand’
This involves ignoring the base and foundation of the problem, the conditions of production – your turn your back, you close your mind, as to how and why you have created this virus
NZ went from solving one problem to realising that this solution gave rise to another and larger certainly longer term problem – they will have to manage quarantine, while (most of) the rest of the world, having failed to solve the first problem, will not
This puts NZ at a considerable disadvantage – if they’d been as foolish as the US was and still is, they’d be better off in the long term
It is not as though this was not clear from the start
You are doing the same – all these little solutions merely roll over into a larger problem – the bug keeps on coming nonetheless, mutating, perhaps getting more lethal, perhaps less, you have no way of knowing foreseeing or preventing, for you treat only the symptoms and not the cause
And, by reflex, in the future a bad bug attack will involve lockdowns again, and so on, more filters perhaps, all those those measures which drag out the death toll but do not diminish it, yet cause you such panick and cost you so much cash
To treat the cause you will have to think beyond what is easy, UV frequencies etc, to what is difficult, how to devise and regulate a way of living and an agriculture and general human health which does not produce such bugs and/or is better equipped to resist them should ever they arise
NZ is no different to its neighbour Australia, which has some cases and has quarantine as well, both countries took similar approaches with similar results. Oh yes and Australia requires those leaving the country to obtain permission first.
The other side of the coin is Sweden which took a low control approach compared to its immediate neighbours who now have opened their borders to other EU countries but have kept their Swedish border closed
Australia and NZ share the same approach to the bug, share first wave success, have a long common shared history and culture, yet can not agree on opening their mutual borders to eachother, despite being ‘in talks’ about it for over two months now
Aus reluctance to let it’s citizens travel overseas, to other countries than NZ, is rooted in fear of a brain drain
Aus has also made the mistake of very seriously angering it’s main trading partner, China, pursuing an almost official policy of racial vilification against many in the local Chinese community, and incidentally throwing away a major source of tourism, inward investment, and a very profitable student business
I think Aus made many mistakes, some listed above: solving the first wave of the bug was one of them in that it threw up many more much more difficult problems –
It is hard not to suppose that to go so much against Aus economic interests let alone common sense very considerable pressure must have been applied by Aus allies
So now – they have no pandemic but they have a ruined economy, and one which will only get worse, no prospects of travel even to NZ, no prospects on inward investment, the very top level brains especially those from recent immigration Asia or India willing to leave, no tourism, no…well the list is long
If this is what they call a solution they are welcome to it
Do not travel if you are afraid to get covid.
The struggle here is not over personal decisions, everyone is able to make their own decision as to whether to travel. The struggle is over how the issue will be presented to the public, or to policy-makers, so as to influence their decisions as to the resumption of air travel.
Thus we end up with two camps, those who think the evidence shows that we could safely begin a step-wise resumption, and those who believe the evidence is that we still shouldn’t allow travel, because it wouldn’t be safe.
According to reporting this morning, domestic air travel in the US has risen to about 25% of what it was at this time last year. So that is a good stepwise increase, it should help to provide conformation one way or the other. As international flights begin to resume, that will add to the data we have.
Airlines will soon suspend middle seat blockage and will resume fully booking flights. That should provide additional confirmation as to safety, again one way or the other.
It will be a progressive evaluation, we have to be aware of the potential to overstep, and remain watchful. We’ve seen in the US the results of advancing too quickly. But we also have to begin moving back toward normalcy, in as measured a way as we can.
The Sun has shown to be effective in helping kill the virus. They even noticed this in the 1918 pandemic. UV light has been shown to kill the virus, but, some UV wavelengths are dangerous to humans, especially to the eyes. This new study seems to indicate that ‘safe’ wavelength UV light may be quite helpful in killing the virus in the air. Maybe they should even think about using fiber light tubes to light up the lungs?
UVC is known to damage lung tissue. So like many anti-viral medical treatments, there would need to be preferential damage to the virus over the lung.
There is a device called “Healight” that is marketed as a catheter UV light source using A and B rather than C. It has not yet progressed to human clinical trials but has been touted by the makers for use on COVID-19 cases. It exploded on social media after Trump’s press conference and was banned for awhile afterwards. It seems to be viewed as unproven and possibly quackery by the medical community.
The benefit of UV ex-vivo is that it hastens the death of the virus in an environment in which it could not survive for long anyway. In fact it would kill any cell, and it does kill the host cells in which the virus lives, thereby killing the virus.
The same would likely be true in an in-vivo environment where the virus is actively reproducing within live cells. In that case, killing the virus with UV would involve killing the host cells as well.
Anti-viral drugs work by inhibiting the virus from gaining access to the cell, or by limiting their reproduction rate within the cell. So you’d need some kind of similar targeting mechanism for the UV treatment, for it to be effective.
We are here to find the real Covid-19 risks and possible solutions.
Not to prove / convince everything is swell / overrated.
Suggestions please for risks, and for solutions
Reduce the amount of passengers on board if necessary. Enlarge pitch to pre 2000 standards (>30/31 inch) to allow fresh air to flow downwards in front of the passengers.
Enforce extra safety measures for the new 777 10 abreast, 787 9 abreast, A350 10 abreast and A330 9 abreast cabins. It is impossible for people not to touch each other / the narrowed shared armrests, and reduce aisle widths when all seats are sold.
Publish the real cabin space available per seat, availability / absence of gaspers, circulated air / air shields, and exchange rates / particle reduction / pressure drop/airflow of HEPA filters used per airline/ aircraft type. Stop using the “brand new”, generalized numbers (99.99% !).
Call out airlines if they communicate overly optimistic, incorrect, half complete information on their covid protection measures inflight or use irrelevant comparisons.
Airlines, have your senior cabin engineering manager sign off on your next advertorial, not the VP Corporate Communications. (S)he probably isn’t the expert and this is flight safety.
Put water/ basic food in the seats before boarding to reduce cabin traffic during flight. Install additional clean lavatories at the gates.
Don’t be afraid & leave responsibility to the airlines /IATA / passengers, they aren’t independent. They just want to fly asap.
are these suggestions for ‘guidelines’ or for regulations – should they, and other measures perhaps, be mandatory industry wide?
who should consult decide and draw up such? who should mandate and enforce?
what about airports? should new measures be considered?
have all risks been identified? is there a checklist to match the solutions suggested?
one obvious question- what about ‘social distancing’ – in airports or planes, is this necessary or not necessary? it has been widely adopted, is this for good reason?
another – what about mandatory testing, both ends?
E.g. ECDC/EASA sets the standard.
-> International airlines can’t be forced, you just are not allowed to fly into/ out / within Europe if you don’t comply with the standard. Like in recent months.
We should implement effective measures, not hide behind open questions and uncertainties. And then have do-not-understand politicians give in.
Show leadership. Half baked won’t convince passengers, specially if new infections show up.
To choose and impose a series of health saving even perhaps life saving measures across the aviation industry, in line with measures to be imposed in other industries and across the board public and private spaces requires-
-A considerable degree of social political cohesion agreement and inclination to allow regulatory authorities and governments, with a large degree of coherence and co operation, to elaborate an overall effective looking and convincing ‘plan’ to deal with a problem widely/universally perceived as responsive/effective to a finite set of technical social and economic measures
Do you believe that this exists, or will?
With respect, it is very easy to state that better filters are better, better attitudes towards human contact and restrained behaviour in every circumstance are better, costing all such at whatever considerable % of GNP it will cost – with the explicit purpose that ‘in order to save lives’ these measures are essential necessary and to pay the necessary taxes will be imposed
I think unlikely – given
the overall confusion & incoherence on display from very nearly every government and scientific ‘expert’ authority and organisation
the low quality death rate largely confined to the already very old very sick
the need to address cause not symptom
I got COVID in an airplane cabin.
Mark, I hope you recovered! Obviously you can’t know exactly, but you probably have some thoughts on what happened. Are you willing to share?
He said he got it in an airplane.
His last words
This does not seeem to be an issue in Asia, it appears.
When I was seerving my conscription I was in our biochemical and nuclear warfare division and there was a quick way to decrease infections on aircraft: the aerobridge.
Once the aircraft door opens, the aerobridge attached, creates pressssure that quickly allows all the air in the aircraft to be abosrbed into a suction pipe above the entrance of the aerobridge. It can accurately pinpoint things we want searched, like mules who swallowed drugs. Or who has a fever. This is what fogs up you wiondows upon arriving in Changi.
There are only two things that need to be done.
1. No contact with passsenger hamds. This means online check in like some of thw carriers like China Airlines, on others. Use of security machinesa for full body x-ray, nobody holds boardbng passes . AIrlines in Asia also adopt a check-in all bags policy. Also, no individual vents.
Once at cruising altitude, the rate of air circulationis such that even if u have it, you wont get it either. You remember the Discovery XHannel using that American Airlines cabin already by a lot.
If all passengers wear nasks, it’d be great.
According to foreczsts made by teams in Asia, due to the inabuility of the West to subsude ot is vkirjing