What does the French tu cest comen rentrer dedan le hangar ou se trouv trois helicoptere mean in English?

The sentence is grammatically incorrect and doesn't quite make sense in French. However, we can guess at what the speaker is trying to say and translate it as:

"How do you get into the hangar where the three helicopters are?"

Here's a breakdown:

* "Tu" is the informal "you" in French.

* "C'est comment" is a common phrase meaning "how is it" or "how do you..."

* "rentrer dedan" roughly translates to "get inside" or "enter".

* "le hangar" is "the hangar".

* "où se trouvent" is a phrase meaning "where are"

* "trois hélicoptères" is "three helicopters".

The sentence is likely trying to ask about the entrance or access to a hangar containing three helicopters.