ETOPS stands for Extended-range Twin-engine Operational Performance Standards. It is a certification that permits twin-engine aircraft to fly routes that may be greater than 60 minutes flying time from the nearest airport that is suitable for an emergency landing. The certification is based on a set of standards that require both the aircraft and airline to comply with. For the aircraft, the manufacturer must demonstrate that flying with one engine is relatively manageable by the flight crew, safe for the airframe, and an extremely rare occurrence. The airline then must showcase that the flight crew’s training and maintenance procedures are up to high standards.
ETOPS approval is a two-step process. First, the airframe and engine combination must satisfy the basic ETOPS requirements during its type certification. This is called "ETOPS type approval." Such tests may include shutting down an engine and flying the remaining engine during the complete diversion time. Often such tests are performed in the middle of the ocean. An airline with extensive experience operating long-distance flights may be awarded ETOPS operational approval immediately, while others may need to demonstrate ability through a series of ETOPS proving flights.
An ETOPS rating essentially gives the distance away from the nearest diversion airport an aircraft can fly and is based on how many minutes an aircraft can fly on one engine before it needs to land. For instance, an Airbus A330neo with an ETOPS 285 rating can fly anywhere as long as it can make it to an airport available for landing within 285 minutes.
ETOPS governs which routes planes fly and can also have effects on how areas with lower demand receive air traffic. This is because airlines don’t want to fly four-engined aircraft to smaller destinations, as this would be inefficient and costly, meaning that these areas just don’t receive long-haul flights.
Overall, ETOPS has revolutionized air travel today, making flying safer, cheaper, and more sustainable for passengers and airlines alike.
