What is msl in aviation?

The Minimum Safe Altitude Warning System (MSL) is a safety feature utilized in aviation to denote the lowest altitude allowed for a specific area. It assists pilots in ensuring their aircraft remains above a safe altitude while flying.

The MSL is typically calculated by adding the obstacle clearance height required by regulations to the altitude of the highest obstacle within a specified area. This calculated value is then rounded up to the nearest 100 feet to determine the MSL for that area.

Pilots must adhere to MSL restrictions to prevent obstacles such as mountains, buildings, or towers from being a hazard during flight. Failure to maintain a safe altitude can result in collisions, accidents, or other dangerous situations. As such, following MSL guidelines is crucial to ensure the safety of both the aircraft and those on board.