They should enter service over the next three to four years.

The three members of the class entered service in 1962.

The A350 will enter service in the first half of 2010.

All of them entered service around the same time in the early 1950s.

They are expected to enter service between 2016 and 2018.

The 371 series set entered service on 16 March 1991.

The last car from the second order entered service on June 30, 2010.

It is expected they will enter service before the end of 2011.

It is expected to enter service by the end of 2011.

The first of these two, number 4000, entered service on May 26, 1909.