Construction delays limited the operational use of the field during 1941.

The system went into full operational use in March 2011.

The first opportunity for operational use came in August 1964.

These models were in operational use from 1962 to 1990.

However, because of their different lineage and operational use, they are not further considered here.

On June 15, 1907, the observatory was given to operational use.

The system was introduced to operational use a year ahead of schedule.

This is the only known operational use of flying boats within central Europe.

It was declared ready for operational use on 2 September 1944.

Unfortunately little has been documented about their operational use over China.