Broj leta je na ukrcajnoj propusnici.

Literally, broj leta means number of the flight.

The noun let means flight, and here it changes to leta because after a noun like broj (number), Croatian normally uses the genitive case:

• broj
  • genitive
• broj leta = flight number

So this is not a plural form here. It is genitive singular of let.

Because broj often requires the thing being counted or identified to be in the genitive.

This is very similar to structures like:

• čaša vode = a glass of water
• kraj filma = the end of the film
• broj telefona = phone number
• broj leta = flight number

So leta answers the question number of what? → of the flight.

It is the locative singular.

The preposition na can be followed by different cases, but here it expresses location:

• na ukrcajnoj propusnici = on the boarding pass

Because it means where something is, Croatian uses the locative here.

Compare:

• na stolu = on the table
• na karti = on the ticket/map
• na ukrcajnoj propusnici = on the boarding pass

Because both words must match the case required by na in this sentence.

The basic dictionary form is:

• ukrcajna propusnica = boarding pass

But after na meaning on, the phrase goes into the locative singular:

• ukrcajnoj propusnici

Both the adjective and the noun change:

• ukrcajna → ukrcajnoj
• propusnica → propusnici

This agreement is normal in Croatian: adjectives match the noun in gender, number, and case.

Ukrcajna propusnica is the standard Croatian term for boarding pass.

It comes from:

• ukrcaj = boarding
• propusnica = pass / permit

So literally it is something like boarding pass/permit.

In everyday travel language, this is the normal term you would expect in formal or standard Croatian.

Je means is, and it is a clitic in Croatian. Clitics usually appear near the second position in the sentence, not always exactly where English would put them.

So:

• Broj leta je na ukrcajnoj propusnici.

is the natural order.

Croatian often places short forms like je, sam, si, se, ga, mu early in the sentence. This is a very common pattern and something learners notice quickly.

Yes. Croatian word order is more flexible than English word order.

For example, you could also say:

• Na ukrcajnoj propusnici je broj leta.

This still means basically the same thing, but it gives slightly more emphasis to where the flight number is.

A rough comparison:

• Broj leta je na ukrcajnoj propusnici. = focus starts with the flight number
• Na ukrcajnoj propusnici je broj leta. = focus starts with on the boarding pass

Both are grammatical.

There is no word for the because Croatian does not have articles like English a/an/the.

So:

• broj leta can mean the flight number or a flight number
• ukrcajna propusnica can mean a boarding pass or the boarding pass

The exact meaning depends on the context.

That is why Croatian learners of English often struggle with articles, and English speakers learning Croatian often wonder where they went.

Not always. Na can mean on, but depending on context it can also be translated as at or sometimes other similar location meanings.

In this sentence, na is best translated as on because the flight number appears on the boarding pass as text on a document.

Examples:

• na stolu = on the table
• na aerodromu = at the airport
• na ukrcajnoj propusnici = on the boarding pass

So the exact English translation depends on what follows and what kind of location is meant.

Yes, leta can appear in other contexts too, which can confuse learners.

For example:

• from let = flight → leta
• from ljeto = summer → some related forms look similar
• leta can also appear in older or literary usage connected with years

But in this sentence, the context makes it clear:

• broj leta = flight number

At an airport or on a boarding pass, no one would misunderstand it.

A very natural English translation would be:

• The flight number is on the boarding pass.

Depending on context, English might also say:

• You can find the flight number on the boarding pass.
• The boarding pass shows the flight number.

But the Croatian sentence is a straightforward location statement: The flight number is on the boarding pass.