BVLOS

BVLOS: flying beyond sight, and what it changes

What BVLOS means, why it is regulated so tightly, and what it takes to get there.

BVLOS stands for Beyond Visual Line of Sight. It is flight during which the remote pilot can no longer see the aircraft with the unaided eye.

Its opposite, flight within sight, is called VLOS.

Why this is the threshold that changes everything

Within sight, the remote pilot sees things coming: another aircraft, a walker, an obstacle. That ability to avoid is the main safety barrier of light aviation, and it costs nothing.

Beyond sight, it disappears at a stroke. Everything it provided must be replaced by something else: a procedure, equipment, segregated airspace, an observer. That is why BVLOS is not declared — it is authorised.

⚠️ Binoculars, a spotting scope or a video feed do not make a flight compliant with visual line of sight. A camera feed does not show what is arriving from the side.

What BVLOS demands in practice

It almost always moves the operation into the Specific category, by one of two routes:

  • a standard scenario, where one covers the case exactly. In Europe, STS-02 targets BVLOS in a sparsely populated environment, with observers;
  • a SORA risk assessment in every other case, examined by the authority.

Both add requirements that visual flight ignores: detect-and-avoid means, a reliable command link, lost-link procedures, and often a ground exclusion area.

The most common mistake

Believing BVLOS is a matter of distance. Distance does not decide — sight does. An aircraft 200 metres away behind a building is beyond sight; the same aircraft 800 metres away over open ground on a clear day may remain within it.

The rule reads on what the remote pilot actually perceives, not on a counter.

Where it leads

BVLOS is the gateway to the uses that make professional drone work pay: linear inspection, network surveillance, mapping of large sites, delivery. It is also where national frameworks diverge most — the UK builds its RPC-L2 and RPC-L3 precisely on it.

Going further

Other terms

See the whole glossary