We're 15 out.?

[keannu]

They're a rescue team for emergencies and they are talking about Estimated Time of Arrival. But what is the usage of "out" here? Is it "till the end"?

A: Bobby, what's our e. t. a.?
B: We're 15 out.

C: E.t. a. 15 minutes.

[Raymott]

They're a rescue team for emergencies and they are talking about Estimated Time of Arrival. But what is the usage of "out" here? Is it "till the end"?

A: Bobby, what's our e. t. a.?

B: We're 15 out.

C: E.t. a. 15 minutes.

From your dialogue, it can only mean "We are 15 minutes away from arrival." This also makes sense without C's comment.