The ship had six commanders during her operational lifetime.

They are expected to have an operational lifetime of 5 years.

The operational lifetime of a lander on the Martian surface will be seven years.

These spacecraft also demonstrated a 16-month average operational lifetime.

It was based on 15 different carriers during its operational lifetime.

At the same time, the Project's aircraft were nearing the end of their operational lifetimes.

The units were designed for an operational lifetime of 30 years.

It has an expected operational lifetime of 15 years.

Their operational lifetime is expected to be 10 years.

It has an estimated operational lifetime of over 15 years.