Quick answer
Departures are вы́лет, arrivals прилёт — one letter apart on every board. Boarding is поса́дка.
On the board
Checking in
On board
At the desk and the gate
Вы́лет or прилёт?
The two words differ by one syllable and hang above two different halls. Вы́лет has the вы- of “out” — out of the country. Прилёт has the при- of arrival. Reading the prefix is faster than reading the word.
Typical mistakes
Я лета́ю в Москву́ сего́дня.
Я лечу́ в Москву́ сего́дня.
One trip now is лете́ть; лета́ть is flying in general.
мой ручна́я кладь
моя́ ручна́я кладь
кладь ends in -ь and is feminine.
Check yourself
Which word means “departures”?