What is a whisky flight?

A whisky flight is a series of three to six whiskies that you put side by side in separate glasses and taste in a fixed order.

The difference from simply pouring a glass lies in that side by side. All the glasses are filled at the same time, so you can go back to the first glass after you have smelled the third. That going back and forth is exactly what makes differences visible that you would not notice per glass on its own: a cask influence, a touch of salt, a smoke note that is suddenly missing in the next whisky.

A flight is not a term from legislation. The word comes from English and here means nothing other than a series or a set.

Three to six glasses of 10 to 20 millilitres is the usual measure; fewer than three gives too little comparison, more than six climbs too high in alcohol.

There is no legal measure for a dram, so the amount per glass differs by occasion. For a comparison you do not need much: 10 millilitres is enough to smell and sip twice. Those who want to chat and come back to the first glass pour 20 millilitres.

Six glasses of 20 millilitres is 120 millilitres of whisky. At 46% alcohol that equals 55 millilitres of pure alcohol, well over four and a half standard glasses. That is the reason to limit the number of glasses, not the taste.

Line up the glasses in ascending order: first the lowest alcohol percentage and the least peat, then each time a step stronger and smokier.

The reason is practical. A heavily peated Islay leaves smoke in your nose and on your tongue, and what comes after you only half smell. The other way round it does work: a light Speyside beforehand costs you nothing.

A workable sequence is four glasses: an unpeated whisky at 40 to 43%, then one that has matured in sherry casks, then a cask strength above 50%, and finally the peated one. Within a flight, otherwise keep as much as possible the same, for example four whiskies from the same region or the same distillery four times at different ages. That way you taste the difference you wanted to investigate.

Four drams of 20 millilitres at 46% together contain 36.8 millilitres of pure alcohol, and that is about three standard glasses.

The sum is short. The Trimbos-instituut counts a standard glass as 10 grams of pure alcohol, about 12 millilitres; for spirits that comes down to 35 millilitres in the glass at 35% alcohol. For a flight, add up the millilitres, multiply by the alcohol percentage and divide by 12.

Four times 20 milliliters is 80 milliliters; times 0.46 is 36.8 milliliters of pure alcohol; divided by 12 is a good three standard glasses. If a cask strength of 58% is in the series, then that one glass of 20 milliliters already holds 11.6 milliliters of pure alcohol, almost a whole standard glass. With the measure per glass you keep that under control.

You need a separate glass for each whisky, a jug of still water at room temperature and a glass of drinking water per person.

A tulip-shaped glass with a narrow rim keeps the aroma together; a straight tumbler lets it drift away. The ISO 3591 standard describes such a tasting glass for sensory analysis: an egg-shaped bowl on a stem, with an opening narrower than the belly. Whisky glasses follow that same idea.

The water does two things. A few drops in the glass lower the alcohol percentage, which makes a stronger whisky easier to nose. In addition, a sip of water between glasses rinses your mouth. Always add the water to the glass, never to the bottle.