Maximum VLOS Distance is the Smaller of ALOS and DLOS

In plain language

EASA's method: work out two distances - one based on the size of your aircraft, one based on visibility - and the smaller one is as far as you can fly while still in VLOS.

Requirement as structured

EASA guidance states that in VLOS, or in BVLOS with airspace observers, the maximum possible distance between the remote pilot (or observer) and the unmanned aircraft results from the smaller value of ALOS (attitude line of sight) and DLOS (detection line of sight). Anything beyond that distance is considered BVLOS. This is illustrative guidance within an AMC annex, not a separately stated statutory distance limit; the binding obligation remains to keep the aircraft in visual line of sight at all times.

Original regulatory text

In VLOS or in BVLOS with AOs the air risk is mitigated by having the UA in sight of the remote pilot or of the AO. The maximum possible distance between the remote pilot or the AO and the UA results from the smaller value of ALOS and DLOS. Anything beyond that is considered BVLOS.

Applies when

operation

VLOS

regulatory category

Specific