A visual inspection is a recurring procedure in aviation Maintenance, Repair & Overhaul (MRO) to ensure the aircraft’s airworthiness. Over 75% of inspections on large transport aircraft are visual. It is the process of using the naked eye at an arms length to inspect and detect visible anomalies that might pose a risk to the continued safe operation of the aircraft.

The walkaround inspection
is a general check to assess the overall condition of the aircraft and its compliance with the safety standards. It is performed by a human inspector by walking around on the ground below the aircraft, as the name suggests.

The general visual inspection (GVI)
is carried out routinely to inspect, locate, and evaluate any visually obvious damage, failure, or anomaly. For most areas, the human inspector requires additional equipment, such as ladders and cherry pickers. GVI’s report damages, and the results of manufacturing errors or component fatigue.

A detailed visual inspection (DVI)
consists of an intensive examination of a specific area, component, or system for the detection of damages. Usually, some tools are required, including the use of a flashlight, magnifying glass, mirrors, or specialistic measuring tools, etc.

A special detailed visual inspection
may be required for damage assessment of a specific item, installation, or assembly.

For most areas, the human inspector requires additional equipment, such as ladders and cherry pickers. This means that the inspector needs to climbs up heights, and it means that the GVI has to take place inside a hangar.

As a drone doesn’t need any additional equipment such as ladders or cherry pickers, it’s not limited to a hangar environment. From a technical point of view, a general visual inspection with a drone can be performed both in- and outside.

From a regulatory point of view drones may or may not be allowed outside the hangar: this depends on local safety regulations.