Human factors : why is flying so tiring
 

Hi

I have now more than a 1000 hours on the bus, and I've noticed that I'm experiencing a special type of fatigue on a regular basis.
I am a night owl rather than an early bird. So it's no surprise that I experience some fatigue if I woke up too early without sufficient sleep. This is not really my question.
My question is about fatigue not related to insufficient sleep. For example, after 3 flights in the afternoon, say a 2PM-11-PM shift, I will experience a weird sort of fatigue during the 4th flight (it's also starting to grow during the third). It's similar to sleep related fatigue but it's not, because as soon as I come home, I'm very awake and unable to go to bed before 3AM.
I'm not really able to explain or even describe this type of tiredness.
Sometimes, a word that comes to mind is "weariness", fatigue related just to the routine nature of the activity and the fact that there still is pressure to do everything right, even if it's easy on a given normal day.

Am I the only one to experience this ? If not, are there ways to lessen this feeling ?

Thanks

You can be sleep fatigued but also feel alert and unable to sleep later on. I’ve always needed an hour or so to “wind down” even after an all nighter. I also used to suffer greatly from being dog tired but not sleepy.

Could it be the cabin air you’re breathing in? What’s in the air? And being in a pressurised cylinder as well.

These are likely the symptoms of increased cortisol levels, which are quite common in our profession. Sleeping alone won’t suffice to bring it down and sometimes you won’t be able to achieve a good sleep due to those high levels.
You need to disconnect for a while and engage in relaxing activities and light physical exercise. Try also getting bored; when you’re to hyped up between flights and possibly other company related engagement such that you feel you’re close to your maximum EGT, switch off. Do nothing. Look for boredom and hang there for a while. It works a bit like a computer reset. Whatever you do, make sure you engage in something you really enjoy - it is the best way to rebalance hormone levels.

I don't know the answer to your question, but the way I dealt with tiredness and fatigue were to give up caffeine, going jogging, and watching my diet.


Caffeine makes you alert, but it stays in your system for 8 hours and prevents you from sleeping properly. Caffeine wakes you up, but caffeine during the day prevents you from sleeping properly, so the next day you are tired and need caffeine to get going again and it becomes a bit of a treadmill.

If you need to sleep down-route, I found that caffeine prevented me easily going to sleep in the afternoon for a night flight. Stopping coffee completely, enabled me to sleep at odd times of the day. I stopped caffeinated coffee, and drink tea or just hot water in the cockpit. (Tea also has caffeine but for some reason it is not absorbed as it is with coffee).


It is important to keep fit, because it just is - you need to keep your whole body slim, fit and functioning to give yourself the best chance of staying healthy and fending off disease, such as cancer etc. But sitting for hours making no physical effort is very bad for our health. The human body is very good at saving energy, so we need to "tell" our bodies to keep working: maintaining our organs and muscles at peak performance.

Going to the gym is one way, but the whole gym process can work to prevent us actually doing it ! Having to sign up to a subscription and be a member. Having to book sessions. Having to pack a bag with shower stuff and a change of clothes. Having to drive and park, or travel to the gym. Having to wipe down the equipment after use, etc, etc. It is not surprising that many just can't be bothered.


Jogging on the other hand is really easy. You can just decide to go jogging whenever you want. Put on a decent pair of running trainers and literally jog from your front door. You can go anywhere, even just along the streets (pavements) around your house. I do that, but also along the canal, river, sea front; through the woods, along footpaths, across the common or moorland etc, whatever is there. And when you get back home - straight into your own shower. No booking, no subscription, no bag of shower gear, no traveling, no parking.


And no time is wasted. Whereas a gym visit can easily take a couple of hours overall; jogging from your front door takes just a long as the jogging takes. Only got an hour?, perfect for a 5km jog.

Jogging also allows you to unwind and de-stress after a duty - I go jogging down-route, often when I wake up very early owing to jet-lag after flying in. Super easy to do.


Diet wise, I try to avoid all sugar and salt. Sugar has a similar effect to caffeine but with a much shorter cycle: Snacking on biscuits in the cockpit gives you a sugar rush which perks you up, but then you get a sugar crash. So then you want more sugar. Our bodies convert sugar straight into fat which it stores. Sugar is super dense pure 100% calories and it is really bad for you.


Salt raises our blood pressure over our lifetime, we actually only need a tiny amount of salt per day.


Anyway........Sorry for the really long post - I went off on one there !! Perhaps I need to go for a run, to de-stress a bit ! :D

Disturbed biorhythms......... ? I found that all my experiences were due to cumulative tiredness. Max duty periods followed by min. rest periods. Captains' discretion being assumed by crewing, to complete the duty. "Days off" working expected during the Summer. It all adds up.............

Better than running, try the Canadian Air Force 5BX plan. Also, use the stairs as often as possible rather than the lift.
https://csclub.uwaterloo.ca/~rfburger/5bx-plan.pdf

Wow. I am sure the 5BX would make you very fit. BUT, it is very complicated, and requires remembering lots of moves and tables of numbers and timings, and I think many couldn't be bothered with it all.


The very best exercise is the exercise that you will readily and regularly do.


For me, jogging is really really simple, and does not require me to follow any regime - or count any thing. Which releases the brain to think about anything you want. Or nothing. And I never time myself or measure myself, nor run to a beat. I just go at the pace that suits me. That's the ease of it, you just gently plod along. I look around me and listen to the bird song, say hello to the cows, see where that footpath goes etc, And it hardly seems like exercising, it's just jogging along and you get automatic fitness.


BTW, yes, use stairs wherever possible, which is also free and easy exercise :ok:, (I am too impatient to use lifts, which keep stopping to pick other people up !!).

Agree with everything Uplinker says - no mention of age in the posts, so I'm assuming the OP is still relatively young, but as you get older you get tired more easily. Obvious, I know but something to consider.

SWBKCB and Uplinker, You are both absolutely right. I used to do 5BX a long time ago during my flying days but now, at my age, walking and some simple exercises for Seniors from this man help to keep me going:-


And this one too to help balance and walking as we age:-

Back in the late 1980's, I was heavily involved in the flight test program for the 767 re-engine program. As I result, there was a month where I flew nearly every day (flight testing is 7-day/week program, so no assurance of getting even one day off - since then they implemented a rule that required at least on day off every 14 days but that wasn't the case then).
Thing is, on most of those flights I didn't do anything besides sit in the back - either reading or looking at the view out the window - and munch my flight lunch. My testing was 'contingency' - if they couldn't find the calm air they needed for the various aero such testing planned, they'd run my tests instead. So long as they could find 'air', I literally had nothing to do.
By the end of that month, I was a zombie - totally exhausted (and I was in my early 30's at the time so it wasn't age). It simply amazed me that I could get that exhausted just sitting. I assumed that stress was a big part of it - flight testing is inherently stressful - although nothing we did was considered 'high risk' - flight testing was incredibly expensive (I heard numbers of $50,000 hr. - probably double that today), so everything was always 'rush-rush'. If someone asked you a question about your test, you didn't get 15 minutes to think about it, they wanted an answer right NOW! Plus the whole environment was stressful - you could almost feel it in the air. Worse, I didn't sleep well - between the residual stress and lack of physical activity, my brain was fried but my body wasn't that tired...

At cruise altitude the cylinder is depressurized vs the pressure on the ground.

Maybe out in left field, but...
 

Could there be some "components" in the human body that are "sensitive" to travel in ways that could be similar to those found in other species, such as birds? Perhaps sensitive to changes in the magnetic field, sunlight angles along with the obvious pressure changes?

Parts of our body may "know" that we've traveled significant distances whilst sitting on our arse and pushing buttons. We are well aware of the lower humidity in most flightdecks, along with other well known factors.

Then again, just sitting at one's desk at home, in a restricted position, (without the relatively frequent up and downs for coffees, loos, snacks, etc, that happen in home settings) for 4 to 8 hours, could be just as fatiguing as a flight of equal length of time?

Feeling the same more and more. Feel my health deteriorating by doing this job. Part time awaits. The ugly truth is we humans were not designed to fly 3 days in a row. The noise, the air, the lack of opportunity for good meals and quality toilet time all contribute to fatigue and tiredeness whilst looking perfectly legal on paper. It's become the industry norm to throw you into an extreme block of duties only to then give you blocks of days off. I would much rather have a day off after each day of flying to recoup. The body needs it.

@ tdracer, that is very interesting. So more than likely, it is the constant low-level stress for hours on end, combined with moments of high workload and stress, that leads to tiredness and fatigue.

Obviously pilots are under this pressure all the time while in control of an aircraft.

Makes it all the more important to de-stress. Physical exercise is a very good way of de-stressing, and keeping fit, slim and healthy gives the body the best chance of coping.

It also seems to be the industry norm to treat FTLs as targets; even if there was no pressing operational need to.
Sometimes I've got the impression that office staff believe pilots can't possibly be fatigued, if the roster fit FTLs....

but you’re still in a pressurised cylinder compared to the ambient pressure that cycles several times on a multi sector day. Not to mention the air

3 days in a row? That would be amazing; the norm in Europe LCC model is 5 or 6 in a row with max fdp days. Then you get 2/3 maybe 4 days off if you’re lucky where you’re not supposed to have a normal life but just rest and get ready for the next smash. It is unhealthy to wake up for days on end at 3/4 am or to go to sleep at 1 am after a late rotation.
Worst mistake of my professional career was to leave the corporate world to fly airliners; I was flying less than yearly half hours in executive compared to airlines and yes I was making half the money but my QoL was 100 times better, even with a non existent roster being on call and I was enjoying every flight. Moving back to corporate now, airlines (except for old school majors with great contracts) are a big no-no in terms of lifestyle.

I’ve long wondered whether the concept of Time Dilation has anything to do with that very specific type of tiredness one feels after a flight.

The attempt by your body or brain to account for and remedy the minuscule but measurable time lost after the high velocity travel may well fatigue it in a unique way.

Its noticeable enough as an inactive passenger, but must be worse for the flight crew who have to work as well.

I can’t find any research or mention of the effects of Time Dilation on ISS crew or astronauts. I suppose if it was a problem the effects would be felt far more severely by them than airline pilots?

I feel as if this may have legs. I will speak to a friend in the biz to see what she knows. Astronauts are given months of special care and attention after they return in order to recoup. Of course mostly to recover physical strength following a zero G environment.