Drinking & Flying

[Monocock]

Does anyone know of a case where a GA pilot has been breathalised at an airfield?

Also, how do we all regard drinking and flying?

Is it a case of "nil" the night before or sensible moderation?

Just interested

[ACW 335]

10 hours bottle to throttle

[Genghis the Engineer]

I've posted this before, but some research I did in the RAeS library a year or two ago bears repetition....

In simplistic terms, this comes out as:-

- 2½ hours per pint of strong beer
- 1 hour each per single malt or small glass of wine.
- And always at-least 8 hours regardless.

Having said that, I'd go with minimum 8 hours, and not more than 2 drinks within a few hours before that as a good rule of thumb.

G




The basic unit of alcohol within the body is mg/100ml of blood (referred to as %mg BAL). Obviously the relationship between how much you drink and BAL is dependent upon sex, weight, and a few other things. But the references seem to pretty much agree on the following rules of thumb for a standard adult:-

1 pint beer: 24%mg within an hour (can be up to 35%mg, depending upon strength of beer which clearly varies)
1 measure spirits: 12%mg within an hour
1 small glass wine: 15%mg within an hour.

The body (liver) then evacuates alcohol at a pretty constant rate of 15%mg per hour - although the references do admit that depending upon physiology it can actually be anywhere between 8 and 25 %mg/hour.


That stuff most of us had some idea about, but certainly it helps work out where we are after a good night out.


Now to the interesting bit - what the various studies gave as effects of alcohol. The various reports, papers and medical textbooks were pretty consistent. From them I came up with the following:-

11%mg - Reduced ability to maintain correct airspeed or flightpath under high workload

15%mg - 1/3 of pilots in fatal accidents had this level or above in their bodies (from autopsy reports)

20%mg - UK legal flying limit. Significant increase in errors on RT, planning and correct following of procedures.

40%mg - US legal flying limit. Major effect on number of errors on RT and following procedures.
- Reduction in g tolerance by between 0.1 and 0.4g.


50%mg - Impaired ability to visually fix or track objects

60%mg - Consistent degredation of long term performance even on low workload tasks.

80%mg - UK legal driving limit

150%mg - loss of self control (exactly what is meant by this wasn't defined)

200%mg - double vision, some loss of memory

400%mg - Loss of consciousness.


Three other notes were interesting...

(1) from a study where they tanked pilots up to 150%mg which was that afterwards when BAL had gone down to zero, visual impairment and disorientation could occur up to 7 hours afterwards.

(2) All the studies agreed that under high workload alcohol degraded pilots' performance much more than under low workload.

(3) Up until very high alcohol levels, virtually all the degredation was of judgment or ability to follow procedure, rather than of actual physical skills.

[Monocock]

OK ACW, but what if your 16th double brandy was at midnight and you were due to fly at 1000 hrs?

I have been out for dinner before with a guy who flies helichopters and he was helped into his car by his wife (who obviously drove). He was due to be flying at 0900 hrs and sure enough he was.

Scary really.

P.S Genghis, I am seriously impressed that you can write so much in such a short space of time or was it cut and pasted?!!!

[ACW 335]

its just a general guidline i was given. I dont drink lots so it doesnt affect me.

Alcohol affects different people in different ways - even your body build can affect they way your body handles alcohol. Personally i wouldn't drink before flying, just like i wouldn't drink and drive.

Genghis is saying 8 - i think im better sticking with 10!

Its personal judgement and discretion!

[FNG]

Just popped back in from drinking on the roof and saw this. Once, when an early PPL stude, I flew with a bad hangover. The instructor later commented that I had seemed very focussed, attentive and quiet during the lesson until I gave him control and grabbed the chunder bag. He gave me an article to read, all about alcohol's effects on the inner ear, as well as upon judgment. He had a "nil the night before" rule, which is probably the best idea, but I admit that I might have a couple of drinks and still fly during the next day. No flying this weekend, so off now to get ratty peeshed.

[Genghis the Engineer]

Can't disagree with you ACW, if only to ensure 8 hours sleep since I suspect not enough sleep wll degrade your performance more than a small amount of residual blood alcohol will, regardless of the legalities.

The reason that I did the research which led to that post (and yes Monocock, I did cut and paste from something I had on my HD - I can type that fast, but not whilst making sense at the same time) is that I was getting worried about the number of crude rules of thumb doing the rounds, and just wanted to know the scientific reality of alcohol and flying. Took me about 3 hours in the Royal Aeronautical Society Library one day whilst waiting for an afternoon meeting.

I tend personally to take a similar view of all professional activities. Anybody working for me has never been left in doubt about my views of lunchtime drinking - bad decisions made in an engineering department can still kill people, they just take longer.

G

[J.A.F.O.]

Drat it all, I thought it was no smoking within 8 hours and no drinking within 50 feet of the aircraft.

[bar shaker]

I was told a story by an EGMC employee about a pilot that arrived last year, who slurred the radio calls and could barely walk to the C room. Upon entering to check in, he was obviously the wrong end of a very long session. EGMC called plod. Plod called Gatwick for giudance. Gatwick advised that there was nothing that could be done and no action was taken. That's just not on.

The law has since changed and we are bound by the same rules as those party going heavy pilots. The law now allows no more than the equivalent of 0.5 pints of beer in your system at the time of flying.

In a way, I find this better. It means you can have a (note the singular) glass of wine with lunch in LFAT and be legal to fly out at 17:00.

I enjoy a pint *much* more than the next man, but there's a time and a place, and a method of transport home that suits the level of inebriation.

[greeners]

Leagle buddy of mine is in the process of publishing a paper on this post the new regs. I'll just say at this stage that it makes pretty worrying reading.

Her conclusion: Only way to guarantee no problems is NO aclohol the night before...:sad:

[Zlin526]

At the risk of provoking some flak, I'm sure some of the worlds favourite airlines could tell us a few things about flightcrew who drink and fly......

Heads down chaps....:ugh:

[Genghis the Engineer]

Just a thought, does anybody have access to a suitable sim - it would be a fascinating exercise to try for ourselves. I wonder if perhaps Mac Smith at Popham would help?

G

[goatface]

The new reg's basically preclude any sort of drinking of alcohol whilst undertaking the privilages of your licence, as an engineer, atco or pilot.
There is an alcohol limt, but I can't recall what it is, and it's so low it's not worth your while to risk it.

Additionally, the Plod no longer have to have "reasonable grounds" to enter your home/place of work to breathalise you, mere suspision or an anonymous report is sufficiant, and they can force entry if required.

The exact wording is contained within the Bill, a copy of which was given to me by my employer.

Given the amount of alcohol participation which I have seen in over 25 years in the industry, I find the new reg's not so much worrying, as common sense, and not before time either.

[Heliport]

The law relating to alochol and aviation is contained in the Railways and Transport Safety Act 2003.

There's a useful explanation and discussion here (http://www.pprune.org/forums/showthread.php?s=&threadid=113035&perpage=15&pagenumber=1).


Zlin526
I hope you don't get any flak for that comment.
Far better if people treat it with the disdain it deserves. :rolleyes:

[AerBabe]

One of the car programmes, possibly Top Gear, did a really simple test a while ago. They had two groups of people & kept one awake for something like 36 hours, and kept the other group topped up with alcohol. I think the result was that the sleep-deprived group performed terribly - they were all over the road & couldn't hold speed. The drunk group were much better - fast reactions & good attention.

Personally I never drink the same day I'm flying. And wouldn't drink much the night before as it would prevent me from sleeping properly. Is it really worth the risk?

[sharpshot]

I'm surprised you have to ask the question.

If you're not sure of the answer, keep the control locks in place.

A lunchtime drink at LFAT and then fly home later..........:rolleyes: :confused:
You obviously hold your pax in high regard!

[bar shaker]

Oh really Sharpshot? How do you come to that conclusion?

[sharpshot]

Been flying for 1 yr Bar Shaker.
Let us now how you've been getting on about 2034.

[Monocock]

Bar shaker

I know where you were coming from and I agree about the glass of wine at lunchtime too. If you are not flying for 5 hrs it is a lot less dangerous than a cigarette just before departure.....

[bar shaker]

Sharpshot

Yes, I have had a license for a year and since getting it have 'only' flown 148 hours.

But I cannot see how that is of any relevance and am still awaiting your explanation for twisting what I said and accusing me of having no regard for my passengers safety.

Monocock, I agree on the cigarette thing and Sharpshot will probably urinating in his plus fours to read that I am a smoker too.

[sharpshot]

You smoke as much as you like. My instructor of many moons ago used to light up as soon as we got strapped in. He was flying in the RAF from 1937 and a survivor - so if it was good enough for him.......

But hey, if you want to publish your bottle to throttle times on a public forum.............

[Monocock]

Please.....

C'mon lads.

B S is hardly an alcoholic making our skies dangerous. He innocently said he might have a glass of wine at midday if he is flying back across the channel at 5pm. I really don't think he's going to be any less concentrated on the task in hand than a very over worked and tired 737 pilot who's flown the same route 17 times in the last 2 weeks...........

Let's not make a mountain.......

Edited to say:

In fact, B S didnt even say he had even had that glass of vino, just that the current rules mean that "one" could if "one" wanted.

[sharpshot]

Very defensive Monocock.............glad you sober up on the beach:ok: :{

[bar shaker]

Not really Sharpshot.

I think that Monocock is just being equally realistic about the risks faced. Flying is statistically dangerous, just mention it to your life insurance provider, assuming that you are a pilot.

The point I was trying to make is that it is now OK to have that glass of wine, but the 14 pint session 8 hours before flying isn't. In my book that's an improvement in the law.

Health and safety is now an intricate part of all of our lives. Much of it is utter bollox. I'm struggling to finish a £25m school because a new H&S rule has dictated that bricklayers must wear eye protection and gloves. These chaps take pride in their work and are refusing to wear the protective equipment. The upshot is that they cannot work on the site. How long before we must wear hard hats, steel toe cap boots and eye protection, along with our hi-viz, just to walk to our aircraft?

You seem a forthright sort of bloke, although you wasted any argument by questioning the duration of my flying career. I love flying and fly a lot, every weekend that's its VFR and many evenings. I'm passionate about it and enjoy improving the perfection of doing it. Thanks to a good bunch of friends I also get to fly many different aircraft, apart from my own. Despite telling me to come bak in 30 years time, you tell us nothing of your flying experience, again assuming you are a pilot.

I suspect that my "glass of wine" post was what most people think (and I know that several have had that drink) and you spurted off some HSE type diatribe. You miss read me and I also suspect that my post reflected the common held understanding.

You are a photographer. You strive to get the shot that no one else has. I suspect that you may often be in a location that the general public may not be allowed to be in. Have you ever considered the danger that your positioning may pose to flight crew or yourself? Of course you have and the risk was zero.

If I ever do have that glass of wine, I will undertake a similar personal risk assesment and I'm sure the wine will complement my food perfectly.




In signing off, aren't statistics wonderful? Genghis' post said that 1/3 of all pilots killed had and a 15mg alcohol content in their blood. So twice as many pilots drove into the deck whilst completely alcohol free. Do we assume from these statistics that we are twice as likely to be killed if flying with no alcohol at all in our blood?

Of course not, but the presumption requires a modicom of common sense :eek:

[LowNSlow]

Genghis , it doesn't have to be a complex simulator. Try firing up a flight sim on the home PC, fly some circuits then have a few of your favourite tipples and fly some more. Amazing how quickly the precision hand/eye co-ordination deteriorates with the application of alcohol....

I always wondered why I could never get that Corsair back on the deck of the carrier on Combat Flight Sim 2 :ouch:

Regarding the lunchtime single glass of wine and flying 5 hours later I'm with barshaker and Monocock . On the basis that one's body will have processed the single glass of wine out of one's bloodstream by takeoff time what is the problem. Better to have rules based on scientific fact than rules based on very broad generalisations (8/10 hours bottle to throttle) which have been abused heavily in the past.

[foghorn]

Genghis' post tallies with the self-imposed rules of thumb that I use:

1 unit = 1/2 pint beer = small pub glass of wine (125ml) = pub measure of spirits (25ml).

Add a fudge factor on to the above for strong beers or home measures of spirits (oooh my hand slipped!) Also watch those large pub glasses of wine and the new extra-generous spirit measures that some pubs have.

Assume it's adsorbed instantly then you process alcohol at 1 unit per hour, the driving limit is 4 units (and I've just learned the flying limit is 2 units).

Don't fly or drive until at least 8 hours from your last drink unless you consumed no more than the limit in the first place when a bit of discretion is allowed. Leave proportionally more time if you've drunk more than 8 units.

And remember that if you're drinking wife beater (Stella Artois), 8 units comes very quickly.

[TonyR]

You could stick to coke or lemonade but you might crash on landing while trying to cross your legs to stop yourself pissing in the cockpit.

[Genghis the Engineer]

Low N Slow, not a fair test - I can't fly a PC flight simulator for toffee anyway.

But, on a serious point, the reports I read seem to show that by the time your hand-to-eye co-ordination has started to degrade, your ability to follow procedures (gear down? Tank changed? Wind component checked?) has gone completely for a Burton. So, yes a PC flight sim might be used (by somebody who can fly it in the first place), but...

- you want to simulate, say, a moderately complex cross-country flight of an hour or so
- You need to do a good job of simulating the overall flight workload (aircraft management, RT, checks, etc.)

And I'm not sure how well sat at your home PC will do that?

G

[sharpshot]

Barshaker - excellent. I don't disagree with most of what you say. However, from a personal perspective, I will not drink for a considerable period prior to flight.

Yes I do have a licence and as you put it, I get very close to planes. Photography is but a hobby.
My father flew from 1940-2001; I can't emulate his achievements, however, I have at least been able to exercise the privilege of the licence for quite a few years now.

I have been to various social gatherings until 02:00 and been airborne by 07:00 with the partygoers - that's life, just doesn't mean I want to be the one that gets caught out.

Zero tolerance = Nil confusion

[LowNSlow]

Genghis a fair point, a lot of people who can land the real thing make a complete lash of it on a sim.

Theoretically with something like FS 2004 you can do a cross-country with realistic scenery and operating procedures.

Now that the old grid I laughingly called a PC has bitten the dust I might get one that can do all of the above. I'll do a test with carefully measured quantities and let you know what happens :ok:

[Evo]

I agree with Genghis - the procedural side of things will probably go first. Overhead joins and PFLs would start to get tricky, and I'd also be interested to know how a bit of booze affects your ability to tolerate a bit of G. Can you still fly a 60 degree banked turn after a pint? after two?

[Fly Stimulator]

Alcohol is all very well, but there is another substance which can cause a great deal of trouble for pilots when drunk to excess before flying.

I think that we are overdue for some official studies and HSE guidelines on its use as well, since it can to my certain knowledge lead to extreme pilot discomfort and to increasing pressure (literally so in fact) to make rushed decisions, particularly with regard to landing.

I am referring of course to that enemy of the long-distance pilot: coffee.

[sharpshot]

Forget the homebased PC flight sim. It's okay for some things like concentration.

It does not simulate turbulence and the instuments shaking and your eyesight trying to focus all the more:uhoh: :uhoh:

[VP959]

Fly Stim,

The IAM did a study on the effects of coffee on flying some years ago as I recall. I got caught up in it at the time as the crew room coffee machines became de-caff only (and worst of all, TEA was banned!).

The principal finding was that caffeine withdrawal set in about an hour or so into the sortie for heavy coffee drinkers, later or not at all for modest or light consumers. The effects were similar to tiredness, in that there was a loss of concentration and increased tendency to make more minor mistakes.

IIRC, these effects went away when the task got stressful, presumably as adrenaline cuts in and wakes you back up.

[Fly Stimulator]

I found that trying to land a Shadow at Clench Common with my legs crossed woke me up quite effectively too! :ooh:

Ever since then I have avoided the evil brew until after flying.

[javelin]

Having watched my mate trying to pee out of the DV window of a Piper Lance at night because he was busting and there were no receptacles in the aeroplane, I have always considered tea and coffee to be far worse than an odd beer. It was the funniest flying experience I have ever had - 8,000 feet over Teeside, Bob trying to reach the window with said tackle and failing desperately, me too convulsed with laughter to fly the aeroplane - thank god for autopilots, we whizzed back to a northern aerodrome, landed, stopped on the runway and he steamed for ages !

After flying in France where the instructor suggested we have a Pastis before we went flying and after being offered wine with my lunch by an Air France hostie - I was Captain at the time, I figure that there is some leeway in this matter !

I declined the wine and stached it for my hotel room after just before you light up !

[bar shaker]

Unless its the sims at Cranebank, I agree that they are a total waste of time for any real test. I do think that pc sims help out in learning procedures though.

I've lapped Brands in 49s in the wet but can't get under a minute in a sim, in the dry :\

[Human Factor]

...just mention it to your life insurance provider, assuming that you are a pilot.

Do you really expect your life insurance company to pay out if they find out you're over the limit?

Realistically, the law is what counts above all else. If you get caught out, you will lose your licence for good. I fly for a living so I have far more to lose than many of you guys, but I feel a professional approach is the undoubtedly the way forward. I get the impression, fortunately, that I'm largely preaching to the converted.

I would suggest though, that the chap who had a wine at lunchtime before flying back at 5pm changes his attitude radically before

a) he causes an accident
b) he kills himself
c) more importantly, kills someone else.

Yes, it is that serious. (This is also the World's Favourite Attitude!)

[bar shaker]

Human Factor

You just don't get this thread do you?

If someone did have that glass of wine, how is he more likely to cause aviation carnage 4-5 hours later?

You say its that serious so, please, give us the professional approach.

[sharpshot]

C'mon Barshaker, don't be so entrenched. Why risk it.

Bet that was only the Indy Circuit in 49 secs:sad:

[bar shaker]

Sharpshot

You are right on both counts.

[johnfairr]

In days gone by, on a NavEx back to the UK from Gibraltar, we landed to refuel our little RAF VC5 at Istres on the South of France, their equivalent of our Farnborough/Boscombe Down.

Quickly nipping in to the aircrew-feeder for more refuelling, none of us were surprised to see the French test-pilots gently quaffing a glass or two of vino prior to their second or third trip of the day.

Guess its in the genes, but no miltary aircrew in the UK forces would contemplate doing the same.

As an aside, I was rudely woken from my slumbers at something like 0215 one morning at Coningsby by the hooter for a no-notice generation of the mighty F4s. The previous night had finished no more than a few short hours before and as I wasn't scheduled to fly that day, had more than done justice to the cheap prices....

Feeling distinctly groggy and still way over the limit, I was nonetheless tasked to taxi and hold in an F4 with a chum who was in a similar condition. Ops knew of our situation and we were the last to be scambled having damn near run out of LOX as we tried to get back to near sobriety!

Wouldn't happen these days, would it??

:rolleyes: :rolleyes: :ok:

[redsnail]

I've flown twice with stonking hangovers.
Never ever again. It hurts and my performance was definitely below par. Whilst I was legal (8 hours before commencement of flight duties) I certainly wasn't ok.

Fatigue/tiredness has a big impact on performance too. This is where the focus of a lot of study and attention is now. FTL's are under threat from Europe.

I can see where Bar Shaker is coming from. 1 glass of wine ~5 hours before flight probably won't impair his/her flying ability in a normal situation. However, if there's an accident there'll be a blood test. If you're dead, there'll be an autopsy. If you're found to have alcohol in your blood then the insurance company won't pay. That's the real risk you're running. If you're happy with that, then fine. Also, the crash investigation team will conduct an enquiry. They will probably find out any way about the consumption of wine during that day.

I don't have any hard facts to hand but I am well aware that (for me) any consumption of alcohol will affect me that day. I won't risk drinking and riding my motorbike. Since the law is quite clear (for me) about drinking and flying I won't mix the two either. I fly for a living, I don't want to lose that.

[Human Factor]

I don't really want to get into a slanging match. The issue is not whether you'd be more likely to cause an accident five hours after one glass of wine. Personally I believe the additional risk is minimal, I wouldn't do it but there are obviously people out there who would.

The issue is actually whether you'll be able to dodge the book that is thrown at you if you do. Part of airmanship involves covering oneselfs back in case you screw up. Whether it's commercial or private avaition which you undertake, you'll still end up before the same judge and if the prosecution can hang something on you, they will.

Be careful out there.

[Chocks Wahey]

You won't find these calculations on your CRP-1 but here's a pretty good way of determining if you are ok to drive : -

For every unit of alcohol you intake your body will need 1 hour to process. For example if you intake 8 units you will be 'clean' in 9 hours. (You start the unit count down 1 hour after consuming the first unit)

Your body will still process the alcohol whilst you are drinking and you do not need to start the count down after you have finished drinking.

Now for men, if you work out how many units you have still in you after subtracting the number of hours, multiply this amount by 7. This will give you your breathalyser reading.

For example if you started drinking at 1200 and consumed 8 units of alcohol by 1700, start the unit countdown at 1300 and this gives you 4 hours. Subtract 4 (hours) from 8 (units) and this leaves 4. Multiply the 4 by 7 and you will get 28, which is what your breathalyser reading will be.

The multiplier for women is 11.

Although everyone is different this method is fairly accurate and is a good indicator of whether you are ok to drive. The legal limit for driving is 35, so 5 units in your system would make you borderline. I would suggest that for flying you should have a zero rating.

[VP959]

With reference to the French attachment to wine, once when flying as a guest aboard an Atlantique on a maritime patrol sortie a few years ago I opened my baggie to find a small bottle of wine included. Wandering up to the flight deck I was even more astounded to see that even the pilots had wine included in their bag meals I was greeted with very puzzled expressions when I suggested that drinking might not be compatible with flying.........

Mind you, even though the quality of their on board catering was excellent, it wasn't quite the same as the steaks, beefburgers etc, and gallons of tea, that came flowing freely out of the galley on our own trusty jet MPA.

[niknak]

I recall that several years ago a PA31 met an unfortunate end in New Zealand.
The post mortem revealed that the pilot (the only person on board), had drunk approximately 2 pints of full strength tonic water prior to departure to quench his thirst, and the quinine content was a significantly contributary factor in the loss of control.

Poor lad should have added some gin perhaps. :(

[bar shaker]

Human Factor

No slanging match will ensue, but you really must read the latest law on this. Its based, quite rightly, on the alcohol in your blood at the time of flying.

You are no longer able to go to those late night parties, banging back the G&Ts, in the knowledge that you will be legal 8 hours later, irrespective of how pissed you still are.

The quirk of this law, which what I was trying to point out in a reasoned manner, is that you can have a glass of wine or half a pint of beer with lunch and then fly that evening. Some/most/all/none may choose not to, but your flight will be legal as your body will have broken down the alcohol many hours ahead of your flight.

Read the Act. As a commercial pilot, your job may well depend on it.

[Human Factor]

Sorry, been away for a bit. My company, in common with others, has more restrictive rules than the act. Trust me, I've read the act, inwardly digested it and there's considerably less than 20mg/100ml in my system! ;)

ATB.

[RichyRich]

Retracted. Re-read the original post by G.

Oh well.... (hick).

[yintsinmerite]

Wasn't there a case about 10 years ago of a guy who had flown from Elstree to Cambridge and back swigging vodka from a bottle before crashing.? Now that is too much alcohol.

Personally, if I am flying with 24hrs, I dont drink at all although I will confess to once having a training flight with a bit of a hang over - slow flight too. Stalls are not good in that state.