Drunk pilots and the rules around alcohol and flying a plane

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What is the alcohol limit for pilots?

The limit for pilots in the UK is 20mg of alcohol for every 100ml of blood, which is one quarter of the current drink-driving limit in England (80mg/100ml). Most countries have a similarly low blood-alcohol limit.

Aviation authorities also generally recommend a "bottle to throttle" period of eight hours or more, prescribing a cut-off time after which a pilot can no longer drink.

In India, it's zero tolerance. In a policy document on pilot alcohol consumption, the Office of the Director General of Civil Aviation states: "Alcohol present in body even in small quantities jeopardises flight safety on several counts and is likely to adversely affect an aviator well into the hangover period". Even 1mg of alcohol content per 100ml of blood would push an Indian pilot over the limit.

So are hangovers dangerous, too?

According to the US Federal Aviation Administration, a hangover can be just as dangerous as the intoxication itself.

They state: "Symptoms commonly associated with a hangover are headache, dizziness, dry mouth, stuffy nose, fatigue, upset stomach, irritability, impaired judgment, and increased sensitivity to bright light. A pilot with these symptoms would certainly not be fit to safely operate an aircraft".

Are pilots ever randomly breathalysed before boarding a plane?

So this is the surprising bit. While some countries do use random testing, in the UK the answer is no.

The UK Civil Aviation Authority confirmed that random testing is not currently used by any UK airline.

A random breathalysing process would likely involve the pilot blowing into a tube for a few seconds. If found over the limit, they would be required to take a second test in front of a witness and then – if the results confirm they are over the limit – removed from the flight with some serious questions to answer, to both the police and the airline.

But not everyone agrees that breathalysing is the way forward. In a blog post, Dr Rob Hunter of the British Airline Pilots Association (BALPA) wrote: "We believe this testing could lead to emotional distress of pilots".

Hypothesising an instance when the system could go wrong, Hunter writes: "A pilot being served a chilled orange juice that, by mischief or mistake, was contaminated with a small amount of alcohol could be over the flying limit without any subjective awareness of the effects of the alcohol".

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So if we don't breathalyse, how are drunk pilots caught?

As it stands, the system in the UK relies entirely on ground staff or cabin crew (or passengers) reporting the pilot to the authorities – as was the case on last week's British Airways flight.

How many pilots have been caught under the influence of alcohol?

While the 2012 film Flight, starring Denzel Washington as an alcoholic pilot, is not based on a true story, there are a handful of real-life examples of commercial pilots caught being drunk behind the controls.

In 2016, Carlos Robert Licona was removed from a United Airlines flight from Glasgow to New Jersey on suspicion of being drunk. The alarm was raised when security staff smelt alcohol on Licona during standard checks. It emerged he and a colleague had been drinking the night before, and a blood sample taken hours after he was removed from the flight showed he was still over twice the 20mg blood alcohol limit.

In 2002, an America West Airlines flight from Miami to Phoenix was ordered to return to the terminal after a report that the pilots were drunk. The two men were found guilty and convicted of operating an aircraft under the influence of alcohol.

In rare instances, inebriated pilots have caused crashes. Two Russian pilots were held partly responsible for fatal accidents in 2011 and 2012.

While stories like these do often emerge in the press, the percentage of pilots being caught drunk in the cockpit per year is extremely low. Out of the 12,480 US pilots tested in 2015, most of them randomly, only 10 came out positive. India's stricter testing regulations caught 46 pilots in 2016.

What is the penalty for being caught over the limit in the cockpit?

Each airline has its own disciplinary policy, typically including a suspension. Then, it's up to the presiding legal system to impose a fine or sentence on the pilot.

In 2013, Pakistani pilot Irfan Faiz was jailed for nine months in Britain after being found to be three times over the legal limit. Faiz admitted to drinking three quarters of a bottle of whisky 19 hours before flying an Airbus 310 from Leeds Bradford to Islamabad.

Does the profession have a drinking problem?

The mental health of pilots is increasingly in the spotlight after the co-pilot of a Germanwings flight deliberately crashed a plane into the French Alps in 2015.

Computerised rostering programmes can entitle pilots to a bare minimum of rest periods between shifts, and the effects of fatigue and long stints away from home may contribute to poor mental wellbeing. Research suggests that symptoms of anxiety and depression can play a significant role in an individual's risk of alcoholism.

In the wake of the Germanwings tragedy, a European Aviation Safety Agency (EASA) task-force put forward a number of recommendations to the European Commission, including: "That there should be random drug and alcohol testing and testing at initial medical certification."

Dr Rob Hunter of BALPA disagrees that there is a drinking problem in the industry. "The worrying thing that has transpired since these recommendations were made is that in various regulatory documents following this tragedy studies of accidents are quoted in support of drug and alcohol testing," he said.

"When we delve deeper into the raw data that these studies are based on we reach an opposite conclusion – the data suggests that there is not a problem of drug and alcohol misuse in large commercial air transport operations."

The Telegraph, London

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