ETOPS is an abbreviation for dual-engine operations with an extended range and is a set of rules governing the operation of twin-engine aircraft at distances greater than one-hour flight time in still air from the respective airports. The corresponding airport is one equipped to support a withdrawal of the type of aircraft being operated. These adequate airports do not take into account current or forecast weather, but NOTAM notifications must be communicated to determine if the airfield remains adequate.
It is normal that a completely new airline should remain for one hour with flight time at the appropriate aerodrome. The speed will be set by the operator who will be used to determine the distance according to the rules, in this case the distance traveled in one hour. Airlines must constantly operate aircraft at a distance from the correct aerodrome.
The most direct route between two places on the earth’s surface is that of a large circle, and the most economical route is usually located next to this line after taking wind and tail winds into account. To deviate a long distance from this ideal route, an airline may be required without ETOP permission. The flight from London to Bermuda had to travel through Scotland, not far from Iceland, Greenland, and then flew along the eastern coasts of Canada and Canada to stay within an hour from an adequate aerodrome, which can take almost nine hours, but direct traffic ETOPs is about seven hours, which saves time and fuel.
Airlines can contact their regulator to increase the time (in minutes) that they can use away from an adequate aerodrome, for example, 120 minutes of ETOP. To determine the scope of ETOPs operations, an appropriate distance is used according to this time and a given speed in still air. The choice of speed not only affects the work area, but the operator must also take into account the influence of the chosen speed on the height from which the aircraft will fall, until the engine fails and the amount of fuel used when flying at lower levels after the engine fails or the pressure is released.
There are more stringent requirements for sending ETOP flights. Aviation engineering checks are performed before each flight, and the aircraft must be maintained at a higher level with increased vigilance of critical items, for example, increased oil consumption may indicate the beginning of engine problems. Flight planning will take into account which adequate aerodromes are suitable for use with predicted weather conditions at the time when the aircraft may need to be diverted. The distance of the ETOPs rule is then applied to these suitable aerodromes. Weather requirements for flight ETOPs have additional safety factors added to increase the likelihood that the airfield will still be suitable for leakage, if required.
