Learn Turkish: Kalkış saati geldi, sefer başlamak üzere. - The departure time has come, the trip is about to start.

The word üzere is a postposition, but when it directly follows a verb in its full dictionary form (the infinitive, like başlamak), the combination means "about to" or "on the verge of" doing that action.

Is kalkış related to the verb kalkmak (to get up)?

Yes! While kalkmak usually means "to get up," for vehicles like buses or planes it means "to depart" or "to take off." By adding the -Iş suffix, we turn the verb into a noun describing the action itself, making kalkış mean "departure."

Why is it kalkış saati and not just kalkış saat?

This is a standard noun compound in Turkish. When linking two nouns to make a single concept (like "departure time"), the second noun needs a possessive suffix. The word saat gets the -i suffix to become saati, properly linking it to kalkış.

Why use sefer here instead of yolculuk for "trip"?

While yolculuk is the general word for a personal journey, sefer specifically refers to a scheduled trip, voyage, or transport service like a designated flight, bus route, or ferry crossing. Since this sentence is about a scheduled departure time, sefer is the most precise word.