Position reports shall contain the following elements of information, except that elements 4), 5) and 6) may be omitted when prescribed on the basis of regional air navigation agreements. (Element 4) shall be included in the initial call after changing to a new frequency):

1) aircraft identification;

2) position;

3) time;

4) flight level or altitude, including passing level and cleared level if not maintaining the cleared level;

5) next position and time over; and

6) ensuring significant point

Where adequate flight progress data are available from other sources, such as surveillance radar, flights may be exempted from the requirement to make compulsory position reports.