View Full Version : A few questions on ETOPS

29th Dec 2009, 20:41
Good day fellow aviators.

1. From regulatory perspective, should there be at least two alternates between ETOPS entry and exit point (to get criticial point between them)? Is it allowed to have only one alternate between ETOPS entry and exit point IF it covers the whole ETOPS area of operation?

2. Could there be more then one "set" of ETOPS entry and exit points? Say in the beginning of flight and then at the end, or should it be treated as a one whole ETOPS "area"?

3. Is it allowed for route to destination alternate (normal, non-ETOPS alternate) to be ETOPS-route, or should all routes to destination alternates remain within 60 mins from suitable alternates?

Spooky 2
29th Dec 2009, 21:38
You might want to Google AC120-42B and see if you can find your answer there. Regardless it is s good reference document regarding ETOPS.

29th Dec 2009, 22:59
1. You never need 2. You always need one. OK, in the end you have two or more for the whole flight. But you just have to have one at a time. How many there are in total for one flight is irrelevant. The change point, where both have the same distance, is the PNR, as you said.

2. Also for that you can have as many as you want. You just need a valid flight plan, and this one has to work according to the Etops rules. You can change your flight plan of course, and some do, you can take a whole bunch of fligth plans with you if you should need it. As soon as you leave inhabited area for a certain distance, you get into Etops area, you have to be covered with a valid alternate (90, 120 or what ever flight times away).

3. Destination alternates have to be within 60 minutes, at least all legal frameworks I flew with, and surely EASA/JAR. Etops is for enroute planning, not for destination alternates. If your destination alternate is further away than 60 minutes, you have none, and you have to calculate with isolated destination.


Plane Dumb
30th Dec 2009, 00:39
CAP 513 is the CAA publication for ref.

You looking at flying the South Atlantic?:E

30th Dec 2009, 08:19
should it be treated as a one whole ETOPS "area"?
That is exactly how it is treated. Draw a "60 minute at one engine inop speed" circle around every adequate airport on a map - and this is the area that a non-ETOPS aircraft is permitted to fly in. The route that it flies - straight line, circles, wiggles etc is irrelevant provided it stays within the permitted area.

For a 90 minute ETOPS approved aircraft, you draw 90 minute circles to determine the area, 180 minutes, 180 minute circles etc. (Wind in this case in not considered, by the way)

It appears as though you are thinking that each route is approved, rather than the ETOPS approval referring to an area of permitted operations.

30th Dec 2009, 11:53
The route that it flies - straight line, circles, wiggles etc is irrelevant provided it stays within the permitted area. Depends on route I'd say.
Some particular routes like over Himalaya require specific escape route thus the route becomes a factor. Even though one stays within the approved circle the real diversion will be outside the limits. I remember a particular case with 120 min etops flight via northern Chinese corridor where at some point between the Pakistan and China a diversion back to Chinese ETOPS alternate using DIR TO wans't an option obviously due to terrain. If I recall correctly highest Grid Mora was around 31000 ft. :ok: