MRJT Additional Procedures — Page 114, Lesson 103

I want to walk you through the start of the MRJT Additional Procedures chapter, and we're beginning with Extended Twin Operations — ETOPS. This is a critical concept for any twin-engine aircraft operating over water or remote areas, so let's build it from the ground up. First, the core problem. If a twin-engine Performance Class A aircraft — that's your typical jet or high-performance turboprop — loses a power unit or certain major systems while flying over water or remote terrain, the situation is more serious than it would be on an aircraft with three or four engines. Why? Because you have fewer engines and systems remaining to handle the diversion. So the regulations place a limit on how far any twin-engine aircraft — and this includes turboprops and reciprocating-engine types — may be from an adequate airfield. That baseline limit is one hour's flight time, in still air and standard conditions, at the normal one-engine-inoperative cruise speed. So if you're within one hour of a suitable airfield at that reduced speed, you're operating under normal rules. Now, if you plan to fly a twin-engine public transport aeroplane beyond that one-hour distance from an adequate aerodrome, that operation is considered Extended Twin Operations — ETOPS. So ETOPS is essentially any twin-engine commercial flight that goes farther from a suitable diversion field than that one-hour threshold. An operator can apply for authorization to conduct ETOPS with a specific airframe and engine combination, within a particular area — for example, the North Atlantic. The key limit here is the maximum diversion time. From any point along the proposed route, the time to reach an adequate aerodrome, at the normal one-engine-inoperative cruise speed under standard conditions and still air, can be up to 180 minutes or less. The specific approved diversion times are 90, 120, 138, or 180 minutes. So you might be approved for 120-minute ETOPS, meaning you can never be more than 120 minutes from a suitable field at that one-engine-out speed. These areas and their associated diversion times are specified on the permission issued by the Regulatory Authority — that's the body that approves ETOPS for that operator. And importantly, an operator shall not conduct operations beyond that one-hour threshold distance unless they have been approved to do so by the Authority, in accordance with EU-OPS 1.245. Before any ETOPS flight, the operator must ensure that a suitable ETOPS en route alternate is available within the appropriate diversion time. So you need a viable alternate airport within that time limit for every point along your route. Let me define the term precisely as the book gives it: Extended Twin Operations are those operations intended to be, or actually, conducted over a route that exceeds that one-hour distance from an adequate aerodrome. So even if you plan to stay within the limit but end up beyond it due to a diversion or reroute, that also counts as ETOPS. To summarize: baseline limit is one hour at one-engine-inoperative cruise speed. Beyond that is ETOPS. ETOPS requires specific approval, with diversion times of 90, 120, 138, or 180 minutes, and you must have a suitable alternate within that time for every point on the route. That's the foundation for everything else in this chapter.