ETOPS

[granard]

If a twin engined aircraft is flying more than 60 minutes away from a suitable operational airfield, with this time being calculated for a single engine operation in still air conditions, then the aircraft is flying ETOPS.

Am I right in saying if a two engine aircraft takes off and now I shutdown the other engine and we fly for 60 minutes the distance that I cover would be the limit for that aircraft, if it crosses this limit this aircraft is now flying ETOPS.

Is this the correct interpretation !!

[seat 0A]

Could you explain your question please?
Why would you continue flying away from the airfield you took off from on one engine?

The ETOPS distance is a set number, which is part of the ETOPS certification.
For instance, in my company for the B777 it is 400 NM.

So 180 ETOPS is maximum 1200 NM from an adequate airport.

[granard]

How is the 400nm calculated?

[Checkboard]

http://www.pprune.org/tech-log/449476-single-suitable-etops-alternate.html
http://www.pprune.org/questions/441756-etops-required-fuel.html
http://www.pprune.org/questions/452489-wind-consideration-etops-departue.html
http://www.pprune.org/flight-ground-ops-crewing-dispatch/290861-etops-flight-planning.html
http://www.pprune.org/tech-log/445039-etops-rules-long-new-flight-routes.html

etc. etc. etc.

[shortfuel]

I'll try to make it as simple as possible:

Am I right in saying if a two engine aircraft takes off and now I shutdown the other engine and we fly for 60 minutes the distance that I cover would be the limit for that aircraft, if it crosses this limit this aircraft is now flying ETOPS.

Is this the correct interpretation !!

Not exactly.

Before flying ETOPS, the aircraft must be ETOPS certified by the manufacturer.
The operator who wishes to operate under ETOPS must go through an approval with its regulatory authorities.

Part of this approval process, a 60 min maximum diversion distance has to be determined (i.e. approved one-engine inoperative cruise speed)
There are different methods to calculate it....

Once this distance has been calculated and approved, you will be flying ETOPS each time your route takes you further than this 60 min max diversion distance from an ADEQUATE airport.

That 60 min distance is fixed under the ETOPS approval and can vary from one operator to another.

In my company, it is 420 NM for all Airbus fleets for commonality reasons.

[granard]

Thanks for the response.

How is this 400nm calculate?

Is it by as I said at the start flying the aircraft on one engine at cruise speed for 1 hour and see what distance this covers.

Now for that particular aircraft it would be 400nm.

[Checkboard]

Not by actually flying the aircraft, but by using the certified single engine performance data. The single engine cruise speed is selected by the airline (who then must allow for the required fuel flow in their critical point calculations).

[JammedStab]

How is the 400nm calculated?

Boeing has a Flight Planning & Performance Manual(FPPM) with information for ETOPS. A chart using MCT is available with distances for 1 hour based on various weights or another performance chart could be used.

[8che]

Granard,


Frustrating isn't it when no one answers your question, so here goes,


Threshold distance (ETOPS) is ;


Maximum distance from an adequate aerodrome for twin engine aeroplane without ETOPS approval. Based on ;


1) Diversion after engine failure
2) Take off at MTOW and gross weight after one hour of flight time
3) Mmo/Vmo speed schedule
4) zero wind
5) ISA conditions


Hope that clears it up

[Oakape]

The calculated distance will vary depending on what speed schedule the operator chooses to use. A faster speed will give a greater distance, but will mean a lower maximum altitude & therefore may give terrain clearance problems, depending on the area of operation for that particular operator. The distance obtained from these calculations by the operator will then need to be approved by the regulator.

Once the operator has the distance approved this becomes the EDTO threshold distance (ETOPS is now referred to as this - Extended Diversion Time Operations). This figure does not change from day to day, as it is a theoretical figure. Therefore the actual time to fly from this point on one engine on any particular day may be greater or less than 1 hour due to wind & the actual speed used on that particular day. The reason I say 'the actual speed used on that particular day' is because you are not obliged to use the nominated speed that was used for the regulatory approval process. On the day you can fly what ever speed you feel appropriate. Just don't run out of fuel!

So this statement -

If a twin engined aircraft is flying more than 60 minutes away from a suitable operational airfield, with this time being calculated for a single engine operation in still air conditions, then the aircraft is flying ETOPS.

is incorrect. The aircraft is EDTO once it passes the EDTO threshold distance in the operators manual. Most use the fix page to put the EDTO threshold distance in & therefore have the threshold distance displayed on the ND as a circle around the EDTO adequate airport/s.

It can be a little confusing as the EDTO threshold is referred to as a time for convenience, when in fact it is a distance. Time & speed are simply used to calculate it. To further complicate matters, the various EDTO times (such as 60, 120, 180, 207, etc) can be calculated using different speeds by the operator, which means that the distances for these various EDTO times are not multiples of each other. For example, my company uses 431nm for their EDTO threshold distance (60 minutes) & 823nm for their 120 minute distance.

[FE Hoppy]

Oakape.
ETOPS is still ETOPS in Europe.

[Oakape]

ICAO has adopted the terminology EDTO, but accepts that some authorities still choose to use the old term ETOPS. EASA & FAA are the two big players that still use the term ETOPS. Both EDTO & ETOPS are basically referring to the same thing. Page 11 explains.

http://www.icao.int/SAM/Documents/2014-EDTO/EDTO%20Module%20%209%20%E2%80%93Summary.pdf

The main thing with EDTO is that three & four engine aircraft are now included in the requirements.

[tdracer]

ETOPs is still the 'official' FAA acronym, but it's become somewhat meaningless since it no longer applies exclusively to "Twin" engined aircraft per the latest FARs (gory details in "Appendix K").

So, in typical government newspeak, ETOPs no long stands for "Extended Twin OPerationS, it's now ExTended OPerations :ugh: Some of you that have been around the industry as long as I have may recall the original acronym - EROPs (Extended Range OPerations) but that was too logical so it got changed to ETOPs:*

EDTO makes a lot more sense given the current meaning of the rules.

[SeenItAll]

And I always thought that ETOPs meant "engines turn or passengers swim" :)
What does EDTO mean? "Engines die, time outstanding" ?
Other definition suggestions are welcome. :D

[Ultralights]

part of the aircraft ETOPS certification is also a lot strickter maintenance regime, with rules like both engines cannot be changed within a certain flight time period of each other etc etc.

[8che]

What does any of that have to do with the posters question ?

[Ultralights]

from the original post, it appeared the person asking the question doesnt quite understand the meaning of ETOPs operations, their initial assumption was it was a time based thing with regards to the aircraft flightpath, so, some of the following responses highlight the fact that ETOPS is a certification issues, with numerous requirements, none of which have anything to do with flight times past certain points. so, in effect, answering the question, and hopefully educating the original poster in what ETOPs essentially means.

[Capt Fathom]

And the original post was from 2011. They probably have their answer by now!

[deefer dog]

EROPS, ETDO or ETOPS. Does it matter? Jesus, some overpaid and under worked desk job hairsplitting idiot will soon probably re-invent Weight and Balance, and come up with something as meaningless (and unmeasurable) connected with Mass!

[Microburst2002]

Granard, you won't manage to understand the whole ETOPS thing by posting this question. Have a good read at all the stuff you have in your OM, FCOM and training docs from your airline, which are not as clear as they should, usually, then come here for clarification. It is a very interesting subject, actually.

[mutt]

For example, my company uses 431nm for their EDTO threshold distance (60 minutes) & 823nm for their 120 minute distance.

My understanding is that the aircraft drifts down, so the initial TAS at altitude is high, it slowly decreases as the aircraft descends, the likelihood is that the aircraft won't have reached the level off altitude in 60 minutes, so you will still have a slightly higher TAS, but once the aircraft levels off, the TAS for the single engine speed will be at its lowest, so basically 120 minutes is not automatically double the 60 minute distance nor is 180 minutes 3 times the distance.

This is different to the methodology used by Jeppesen flight planning where the aircraft is immediately considered to be at 10,000 feet immediately following the event.

[c100driver]

Try not to confuse operations with certification as they are two different fish.

Out to 180 minutes is only required to be a fixed distance (no wind accounted for) based on the declared (certified in the operation manual approved by your regulator). Different regulators can and do have a different certification view though.

Currently my regulator requires wind allowances when operating beyond 180 minutes out to 240 minutes. 240 also has a greater fuel monitoring requirement that required an FMC upgrade in 17.1 on the B777.

[FullWings]

I think one of the most relevant things to remember is that it’s just a planning exercise to make reasonably sure that you have somewhere half-decent to go if something happens. You don’t have to divert to your nominated ETOPS alternate(s), as someone was trying to convince me the other day: anywhere sensible and justifiable will do...

[punkalouver]

part of the aircraft ETOPS certification is also a lot strickter maintenance regime, with rules like both engines cannot be changed within a certain flight time period of each other etc etc.

A little bit of interesting info....

One of the requirements for granting ETOPS approval at service entry is that the manufacturer will have performed a 3000 cycle test on the engine and then stripped the engine down and carried out a detailed examination.

RR has yet to do that for the Trent 7000 as of late last year resulting in 180 minute ETOPS with a 500 cycle limitation on the engines and an ETOPS expiry date of year end for full compliance.

[Mr @ Spotty M]

You are a little late with your news, l believe the aircraft has since received 180 minute ETOPS clearance without the 500 cycle limit.
Earlier this week it also received EASA ETOPS (EDTO) clearance for beyond 180 minutes.

[punkalouver]

You are a little late with your news, l believe the aircraft has since received 180 minute ETOPS clearance without the 500 cycle limit.
Earlier this week it also received EASA ETOPS (EDTO) clearance for beyond 180 minutes.

Thanks,
I posted the info with the intention of providing interesting info about the certification process, not from a newsworthy point of view. Hope you found it interesting and am hoping for more interesting certification info as a reply.