Expected increase file sizes for ADRS 1345 April/May

Due to the introduction of the new Iridium SafetyCast GMDSS satellite system, The UKHO are having to re-write large sections of ALRS Volume 5, and consequently ADRS1345.  As there will be a significant number of new images for these new sections, over the next four or five weeks, we anticipate that the file sizes for ADRS1345 will be larger than normal during that time.

The UKHO cannot confirm precisely how much larger these files will be however, we do not expect these increases to cause significant issues to users. Where possible, they will attempt to stagger the introduction of these sections to minimise impact on customers.

Should the file sizes at any point exceed the normal recommended sizes accepted by user systems, we will update you again accordingly.