Simbrief ETOPS waypoint radius?

[Marc Stanford]

Hey guys

So with Simbrief it has a nice little feature of calculating the extended operations regimen for you, it also gives you waypoints such as entry, exit, equitime point, etc. I was wondering what are the radius distance for the following waypoints:

ENTRY

ETP

EXIT

I never been able to figure it out, someone suggested 480nm but I'm not sure if it's fir all of it.

[Darren Howie]

Most Airbus A320 family aircraft have a 60 minute limit of around 400-420nm. This means if non ETOPS you must stay withing that distance.

Most A320 approvals are 120 minutes but they can be longer so your looking at about 800nm as a max diversion distance but up to 850 as a general value.

Entry and exit location varies according to operator. Some operators want you ETOPS ASAP as if you have a technical issue you are already in the ETOPS segment so it might end up being a Captains decision. if you where not already ETOPS you may be prevented from doing so.

Some companies use the 60 minute distance but many go ETOPS at TOC plus 100nm or so which gives you time to get weather updates, establish flight following comms with the company.

EXIT is normally the 60 minutes div distance ie 400-450nm.

ETP is the equi time point on the flight planned diversion airfields chosen from among those approved by each company for planning purposes. Note where a crew diverts to is up to them but for planning you must have approved divert fields.

HTH

[Alexander Polcher]

8 hours ago, Marc Stanford said:

Hey guys

So with Simbrief it has a nice little feature of calculating the extended operations regimen for you, it also gives you waypoints such as entry, exit, equitime point, etc. I was wondering what are the radius distance for the following waypoints:

ENTRY

ETP

EXIT

I never been able to figure it out, someone suggested 480nm but I'm not sure if it's fir all of it.

Hi Marc,

I have written something in the below mentioned posting from June 7 about this.

If you have further questions beyond this, give me a hint.

Best Regards

[Alexander Polcher]

8 hours ago, Darren Howie said:

Most Airbus A320 family aircraft have a 60 minute limit of around 400-420nm. This means if non ETOPS you must stay withing that distance.

No, every two-engined aeroplane has a limit of 60min OEI-distance. Distance is depening on the certified OEI speed.

8 hours ago, Darren Howie said:

Most A320 approvals are 120 minutes but they can be longer so your looking at about 800nm as a max diversion distance but up to 850 as a general value.

Same here - the Airbus A320 series is approved for 180min. Which approval is used is highly depending on the operator.

One-Engine-Inoperative (OEI) speed x diversion time = max. diversion distance. (changed time to distance)

8 hours ago, Darren Howie said:

Entry and exit location varies according to operator. Some operators want you ETOPS ASAP as if you have a technical issue you are already in the ETOPS segment so it might end up being a Captains decision. if you where not already ETOPS you may be prevented from doing so.

Sorry, I don't know what you are talking about, but never heard about this procedure. ETOPS Entry Point (EEP) and ETOPS Exit Point (EXP) are hard facts and calculated for each scenario in the same matter. Once you exceed the Threshold Distance you are ETOPS.

8 hours ago, Darren Howie said:

Some companies use the 60 minute distance but many go ETOPS at TOC plus 100nm or so which gives you time to get weather updates, establish flight following comms with the company

Never heard of this or seen any regulatory basis for this. Could you please state a regulatory fact about this?

Best Regards

[Darren Howie]

1 hour ago, Alexander Polcher said:

No, every two-engined aeroplane has a limit of 60min OEI-distance. Distance is depening on the certified OEI speed.

 

Alex i would of thought thats very obvious and to be exact now ALL transport aircraft regardless of engine number ie 2,3 or 4 are restricted by authorities under the title of EDTO. The term ETOPS is only used by aircraft manufacturers as a substitute but EDTO applies to ALL aircraft irrespective of engine numbers. EDTO threshold has also been raised to 90 minutes in many countries around the world however for simplicity and consistency 60 minutes is generally still used as is the outdated term ETOPS.

1 hour ago, Alexander Polcher said:

Same here - the Airbus A320 series is approved for 180min. Which approval is used is highly depending on the operator.

 

The aircraft is certified for operations up to 180 minutes however each operator must also be certified and apply for a specific ETOPS time limit. This is dependent upon maintenance records, standards and a huge list of other requirements. An operator cannot simply say "I want a 180 ETOPS approval" they must have a long track record that is studied by the regulator etc of every aspect of the organization. It is far easier to get a 120 approval than 180 hence why 120 is the standard for many 320 operations.

 

1 hour ago, Alexander Polcher said:

One-Engine-Inoperative (OEI) speed x diversion time = max. ETOPS diversion time
 

I think you are a little confused here regarding how this works. Its FAR more complex than that simple formula far more. The maximum diversion time ie minutes is set by the regulator for an aircraft based off its specific ETOPS approval which is put in for by a manufacturer ie Airbus.

From that time ie 180 or more generally 120 an operator puts in an approval request based on its own values derived from Airbus material.

The distance is determined based off what diversion strategy(speeds, descent calculations etc) a company wants to use and the listings and variations of these are endless.

So its rare for two airlines to have the same specific values ie distances as they are almost certainly planning strategy on differing speeds etc to determine the OEI distance.

Having been approved for ETOPS operations after a long convoluted approval process the airline has its own specific ETOPS distances that stem back to the speeds etc put in for by the company. So my airlines approval specifies what maximum speeds will be used for the calculation of the distances maybe different to another operator as they have used differing diversion "speeds" meaning the critical distances are different.

The distance must also allow for drift down etc so no the formula you quoted is not correct its nowhere near that simple.

1 hour ago, Alexander Polcher said:

Sorry, I don't know what you are talking about, but never heard about this procedure. ETOPS Entry Point (EEP) and ETOPS Exit Point (EXP) are hard facts and calculated for each scenario in the same matter. Once you exceed the Threshold Distance you are ETOPS.

Never heard of this or seen any regulatory basis for this. Could you please state a regulatory fact about this?

 

As i specified above numerous operators choose to use differing ETOPS entry points.  An ETOPS entry point can be at any point chosen from departure point up to the critical OEI. You MUST be ETOPS by the time you get to critical OEI distance however there is nothing stopping an airline starting ETOPS flight procedures prior to reaching that point.

Where you or a company chooses to go ETOPS can be at ANY point from the departure airport up until its gets to its OEI distance.

Obviously completing all of the ETOPS requirements prior to getting to that point makes it impossible if to close to departure airport. The only requirement is that you cannot proceed past the OEI critical distance without being ETOPS compliant. The advantage of going ETOPS sooner rather than later is that should a system failure occur that precludes starting at ETOPS segment happen if you have not gone past your Etops Entry Point you cannot legally continue. If however you have past the entry point it may be possible to continue. Likewise should weather requirments change once you are in your ETOPS section of the flight the conditions change. Again going ETOPS early has significant operational advantages hence why many airlines choose to nominate the point when ETOPS procedures will commence.

Its a similar scenario to a long flight with multiple ETOPS segments again rather than being non etops,etops,non etops,etops non etops on a very long flight many companies will only run one ETOPS segment running from just after TOC at departure aerodrome until  Etops exit point.

When we operate from Australia to the USA West Coast we run leaving Sydney ETOPS from TOC plus 100 or so depending on route all the way to lets say 450nm to go into LAX. Even though techinally flying over Hawaii we are for almost 900nm non ETOPS as we are within range of Honolulu. We have only one Entry and one exit point not multiple.

The key point is your entry point can be no further than the OEI distance but there is nothing to stop it being less based of regulator approval.

Cheers

 

[Alexander Polcher]

36 minutes ago, Darren Howie said:

Alex i would of thought thats very obvious and to be exact now ALL transport aircraft regardless of engine number are restricted by authorities under the title of EDTO. The term ETOPS is only used by aircraft manufacturers as a substitute but EDTO applies to ALL aircraft irrespective of engine numbers. EDTO threshold has also been raised to 90 minutes in many countries around the world however for simplicity and consistency 60 minutes is generally still used as is the outdated term ETOPS.

Not in Europe. Our legislative basis is EU VO 965/2012 Air Operations which states, that Extended Diversion Time Operations (EDTO) has not been applied but Extended Range Operations for two-engined Aeroplanes (ETOPS) is still in charge.

Concluding, for european operators, we do apply those rules only to two-engined aeroplanes.

I am also keen to know, where EDTO applies for 90min Threshold Distance?

36 minutes ago, Darren Howie said:

The aircraft is certified for operations up to 180 minutes however each operator must also be certified and apply for a specific ETOPS time limit. This is dependent upon maintenance records, standards and a huge list of other requirements. An operator cannot simply say "I want a 180 ETOPS approval" they must have a long track record that is studied by the regulator etc of every aspect of the organization. It is far easier to get a 120 approval than 180 hence why 120 is the standard for many 320 operations.

Exactly what I've stated in the article mentioned above.

TCDS -> max. approval for ETOPS max. diversion time.

Operator -> needs to be certified and chooses which to use in conjunction with the National Aviation Authority (NAA), as well as the OEI-speed.

36 minutes ago, Darren Howie said:

I think you are a little confused here regarding how this works. Its FAR more complex than that simple formula far more. The maximum diversion time ie minutes is set by the regulator for an aircraft based off its specific ETOPS approval which is put in for by a manufacturer ie Airbus.

From that time ie 180 or more generally 120 an operator puts in an approval request based on its own values derived from Airbus material.

The distance is determined based off what diversion strategy(speeds, descent calculations etc) a company wants to use and the listings and variations of these are endless.

So its rare for two airlines to have the same specific values ie distances as they are almost certainly planning strategy on differing speeds etc to determine the OEI distance.

Having been approved for ETOPS operations after a long convoluted approval process the airline has its own specific ETOPS distances that stem back to the speeds etc put in for by the company. So my airlines approval specifies what maximum speeds will be used for the calculation of the distances maybe different to another operator as they have used differing diversion "speeds" meaning the critical distances are different.

The distance must also allow for drift down etc so no the formula you quoted is not correct its nowhere near that simple.

You are mistaking ETOPS calculation scenarios (OEI, Decompression, OEI + Decompression -> ETP) for diversion calculation by regulatory basics for determination of the ETOPS and non-ETOPS sector.

36 minutes ago, Darren Howie said:

As i specified above numerous operators choose to use differing ETOPS entry points.  An ETOPS entry point can be at any point chosen from departure point up to the critical OEI. You MUST be ETOPS by the time you get to critical OEI distance however there is nothing stopping an airline starting ETOPS flight procedures prior to reaching that point.

Where you or a company chooses to go ETOPS can be at ANY point from the departure airport up until its gets to its OEI distance.

I have to admit I can't follow your abbreviations. With "OEI distance" you mean the Threshold Distance, right?

Of course you can conduct an ETOPS flight flying accross europe by simply delecting all adequate aerodromes - wherever the advantage is.
 

36 minutes ago, Darren Howie said:

Obviously completing all of the ETOPS requirements prior to getting to that point makes it impossible if to close to departure airport. The only requirement is that you cannot proceed past the OEI critical distance without being ETOPS compliant. The advantage of going ETOPS sooner rather than later is that should a system failure occur that precludes starting at ETOPS segment happen if you have not gone past your Etops Entry Point you cannot legally continue. If however you have past the entry point it may be possible to continue. Likewise should weather requirments change once you are in your ETOPS section of the flight the conditions change. Again going ETOPS early has significant operational advantages hence why many airlines choose to nominate the point when ETOPS procedures will commence.

Basically said - you go ETOPS early because you can continue once you have a critical system failure of any ETOPS relevant Group 1 or Group 2system? Interesting perspective. We've diverted in such a case or flown non-ETOPS.

36 minutes ago, Darren Howie said:

When we operate from Australia to the USA West Coast we run leaving Sydney ETOPS from TOC plus 100 or so depending on route all the way to lets say 450nm to go into LAX. Even though techinally flying over Hawaii we are for almost 900nm non ETOPS as we are within range of Honolulu. We have only one Entry and one exit point not multiple.

You are as long non-ETOPS as you are flying within the range of PHNL as you are flying within your Threshold Distance.

When your OEI-speed it 450kts TAS, your radial is 450nm miles. Which means you can only be 900nm non-ETOPS if your are flying exactly the inbound and outbound radial overhead the ETOPS En-Route Alternate Airport.

Example: https://www.flightradar24.com/data/flights/aa72#2835a1d8

Assuming that the SYD-LAX routing is usually conducted on airway B581 or nearby, see above mentioned flight, the aircraft will not be anywhere near the ~ 400NM Threshold Distance of Honolulu (PHNL).

Of course this is based on a 207min approval, and as I don't have a profund knowledge of any operators OM-C Route Manual in this area and available alternate airports I've chosen then by a rough guess. But assumed that you enlarge your One-Engine-Inoperative (OEI) speed by x-times and certifiy it to a range where you would match the non-ETOPS distance for a few minutes of Honolulu, you woud still have to operate two segments on ETOPS.

a) SYD - HNL

b) HNL-LAX

I am not really aware of what is planned there, but I can't follow your descriptions. Would be nice if you could show a) legal details and b) a flightplan in detail.

Regarding your mentioned Extended Diversion Time Operations (EDTO), it is ICAO Document 10085 First Edition 2017. I can't find anything else besides a 60-minute threshold in detail.

[Darren Howie]

Ok first many of the EDTO requirements have already been implemented world wide.

You will notice ETOPS regulations for instance do not refer to fire extinguishing requirements and aircraft operating into or through Australian airspace must meet all of the EDTO requirements. As 60 minutes is more restrictive it covers you for EDTO and for most countries following EDTO or like Europe who will follow EDTO.

A quick read of the EDTO requirements will show you the threshold distance has been increased to 90 minutes in several countries but again for consitstency 60 minutes is maintained to ensure consistency.

11 minutes ago, Alexander Polcher said:

Not in Europe. Our legislative basis is EU VO 965/2012 Air Operations which states, that Extended Diversion Time Operations (EDTO) has not been applied but Extended Range Operations for two-engined Aeroplanes (ETOPS) is still in charge.

Concluding, for european operators, we do apply those rules only to two-engined aeroplanes.

I am also keen to know, where EDTO applies for 90min Threshold Distance?

Exactly what I've stated in the article mentioned above.

TCDS -> max. approval for ETOPS max. diversion time.

Operator -> needs to be certified and chooses which to use in conjunction with the National Aviation Authority (NAA).

You are mistaking ETOPS calculation scenarios (OEI, Decompression, OEI + Decompression) for diversion calculation by regulatory basics for determination of the ETOPS sector.

 

 

Im sorry im not mistaking anything.

You clearly stated that the diversion time was "One-Engine-Inoperative (OEI) speed x diversion time = max. ETOPS diversion time" as i said above this is incorrect.

Firstly its not a time but a "distance" based off a time. To a flight crew a time diversion value is completely useless hence why the ETOPS failure scenario is based off distance not time even though its a time based diversion plan.

Lets be clear the "operator" chooses the diversion strategy and speeds it intends to use not the regulator. The regulator checks to ensure the strategy and distances determined are acceptable.

The advantage of not using multiple airports to generate a ETOPS compliant flight plan is simple. If your using an airport to create a flight plan and prior to crossing the ETOPS entry point for whatever reason it become unavailable you now must generate and pass on a new complaint flight plan. This causes delays or possibly a diversion if the change occurs close to the ETOPS entry point. There are other logistical requirements as well like ensuring ATC, ground staff and fire fighters are available these all cost money.

You are confusing "critical system failure" with a failure. there are MANY in flight failures that do not require a diversion. A "Critical System Failure" by definition requires an immediate diversion to an adequate airport if you are conducting an ETOPS segment. There are also many system failures that do not permit a crew to operate ETOPS but if already in the ETOPS segment may at crew discression to continue. This is the advantage of having an early ETOPS segment commencement.

Perfect example you lost a single generator 40 minutes after take off. if you have not gone past your ETOPS entry point you cannot continue the flight as ETOPS operations are not permitted "TO COMMENCE". If you have already commenced ETOPS operations ie you are passed your ETOPS entry point first its not a critical system. these are defined by Airbus and a single generator failure is not a critical system failure.

This means you can continue with the flight.

In your example try it again but this time overhead PHNL ie YSSY KLAX via overhead PHNL. In theory you would have two ETOPS segments one from YSSY to PHNL then from PHNL to KLAX. Almost every operator running over the Pacific runs only one ETOPS segment staying ETOPS even though they are flying directly overhead PHNL. This means you will be ETOPS from lets say using ETOPS entry and exit of 440nm from 440nm SYDNEY until 440NM LAX. You will be ETOPS the entire flight This is because any aircraft defect that would not allow entry back into ETOPS operations would require a diversion. Do not confuse a critical system failure with a normal non critical failure that can stop ETOPS entry. This northerly track occurs due favorable winds and flying further north early to take advantage of westerly winds. The very scenario i raised that having multiple ETOPS segments is not only confusing but creates many technical and legal issues that are easily done away with by following ETOPS procedures the entire way.

In short.

The Threshold distance is determined by the operator based off speeds "IT DETERMINES" that comply with Airbus diversion speed strategy ie .78/320 followed by LRC on one engine. From these speeds a distance is determined the Threshold distance beyond which ETOPS must be conducted. I have said this like three times now and is backed up by point B in your shot above the distance is OPERATOR DETERMINED.

The 120 or 180 distances are not multiples of that Threshold distance as they are determined from Airbus documentation.

When you can commence ETOPS segment can be as soon as an operator desires but no later than the Threshold distance.

As you can see there is no requirement to not commence ETOPS procedures until the entry point. This means should an operator wish and many have over the years you can in theory start ETOPS proceures the minute the aircraft is airborne however this is impractical in almost every case. Many operators choose to use the ETOPS entry point as the start of ETOPS operations but as i have explained already being ETOPS when a failure(not a critical system failure as they ALL require diversion) or weather changes by not being ETOPS can require significant diversion or replanning.

The ETOPS entry point is the very latest you can start ETOPS procedures not the first point. Do not confuse ETOPS definitions with flight deck Etops procedures.

Etops rules and Etops procedures are very different just like an Etops flight plan. The flight plan is only a legal document to dispatch the aircraft under the various State and International laws. Because a flight plan only lists say 5 diversion airfields certainly does not mean they are the only ones you can divert to.

 

 

 

 

 

 

 

[Stu Antonio]

[Alexander Polcher]

Quote

You will notice ETOPS regulations for instance do not refer to fire extinguishing requirements and aircraft operating into or through Australian airspace must meet all of the EDTO requirements. As 60 minutes is more restrictive it covers you for EDTO and for most countries following EDTO or like Europe who will follow EDTO.

Are fire extinguishing requirements not required in Australia, or not for ETOPS?

Quote

AMC 20-6 Revision 2 (Eff. 23/12/2020)

Section 4 Terminology

d. ETOPS significant system
ETOPS Significant System means the aeroplane propulsion system and any other aeroplane systems whose failure could adversely affect the safety of an ETOPS flight, or whose functioning is important to continued safe flight and landing during an aeroplane diversion.
Each ETOPS significant system is either a Group 1 or Group 2 system based on the following criteria:

(1) ETOPS Group 1 Systems:
Group 1 Systems are ETOPS significant systems that, related to the number of engines on the aeroplane or the consequences of an engine failure, make the systems’ capability important for an ETOPS flight. The following provides additional discriminating definitions of an ETOPS Group 1 Significant System:
(i) A system for which the fail-safe redundancy characteristics are directly linked to the number of engines (e.g., hydraulic system, pneumatic system, electrical system).
(ii) A system that may affect the proper functioning of the engines to the extent that it could result in an in-flight shutdown or uncommanded loss of thrust (e.g., fuel system, thrust reverser or engine control or indicating system, engine fire detection system).
(iii) A system which contributes significantly to the safety of an engine inoperative ETOPS diversion and is intended to provide additional redundancy to accommodate the system(s) lost by the inoperative engine. These include back-up systems such as an emergency generator, APU, etc.
(iv) A system essential for prolonged operation at engine inoperative altitudes such as anti-icing systems for a two-engine aeroplane if single engine performance results in the aeroplane operating in the icing envelope.

 

Quote

You clearly stated that the diversion time was "One-Engine-Inoperative (OEI) speed x diversion time = max. ETOPS diversion time" as i said above this is incorrect.

One-Engine-Inoperative (OEI) Speed x max. diversion time = max. diversion distance. Typing error.

Quote

Lets be clear the "operator" chooses the diversion strategy and speeds it intends to use not the regulator. The regulator checks to ensure the strategy and distances determined are acceptable.

Exactly what I've described in my ETOPS posting.

Quote

You are confusing "critical system failure" with a failure. there are MANY in flight failures that do not require a diversion. A "Critical System Failure" by definition requires an immediate diversion to an adequate airport if you are conducting an ETOPS segment. There are also many system failures that do not permit a crew to operate ETOPS but if already in the ETOPS segment may at crew discression to continue. This is the advantage of having an early ETOPS segment commencement.

As seen above, I was exactly pointing out the ETOPS significant systems (Group 1 or Group 2).
For the rest of the posting, I will statue that we disagree.

[Sabine Meier]

this is what happens when you get a background from one part of the world with a background from another. aviation is filled with these differences.

[Darren Howie]

12 minutes ago, Alexander Polcher said:

Are fire extinguishing requirements not required in Australia, or not for ETOPS?

 

One-Engine-Inoperative (OEI) Speed x max. diversion time = max. diversion distance. Typing error.

Exactly what I've described in my ETOPS posting.

As seen above, I was exactly pointing out the ETOPS significant systems (Group 1 or Group 2).
For the rest of the posting, I will statue that we disagree.

By fire extinguishing requirements it applies to 3 and 4 engine aircraft as well as twins.

this is the entire purpose of EDTO to extend ETOPS safety requirements from twins to all aircraft.

Example in a 747 or A380 pax aircraft whats the point in being 5 hours from a diversion airport if your cargo hold fire extinguishing only lasts for 180 minutes?

Under EDTO the fire extinguishing etc must be capable of covering the entire diversion and 3 and 4 engine aircraft also have threshold distances buts its based off other systems not engine reliability.

This is exactly why the world is adopting EDTO as its more than just engine issue which ETOPS only addresses now its all aircraft systems this is the major change EDTO brings.

This is not about servicability but about its ability to perform its function hence why 3 and 4 engine aircraft must be fitted with expanded fire fighting capability if they with to operate over exteneded diversion differences.

 

Your quote "One-Engine-Inoperative (OEI) Speed x max. diversion time = max. diversion distance. Typing error."

This is incorrect and not the case.

All the aircraft i have flown have all had a decrease in the second and third hour.

For instance the A320 for one company is 427 Threshold and 830 for 120 not exactly double. Likewise the speed is variable in the first hour as to derive the Threshold distance a driftdown allowance is added in this is why the first hour is 427 and the second is 403(830-427)

The ETOPS significant systems are not what crew are trained for in terms of "Etops Critical systems" As i was explaining many systems not covered by your class one or two can negate you doing ETOPS operations if an MEL has been applied. The Airbus MEL is obviously very thorough in defining restrictions on ER operations (ER is Airbus talk for ETOPS) and there are many things which preclude ETOPS not in the very short list you have there.

This is why it is advantageous to star your ETOPS segment as early as possible and why many airlines do not wait for the Etops Entry Point to start ETOPS and stay ETOPS as long as possible.

You may choose to disagree but this is the way it works in the real world on very long Etops segments.

Airlines do not want aircraft diverting and neither do Airbus as any Etops diversion is logged against the airline and Aircraft part of the record keeping that forms Etops maintenance monitoring.

Simple scenario two A320's both doing Etops sectors both suffer a generator failure 50 minutes from departure airport say 400nm down plan.

The one who was going Etops 100nm after TOC at say 230nm will be able to continue to destination as it passed its Etops entry point prior to the failure and flight continuation is a Captain decision. The one still some distance from its Etops Entry will be required to return as it is not legal to pass the Etops entry point with a Generator U/S.

This is exactly why airlines do an early Etops entry as a day to day procedure and why its advantageous to stay ETOPS as long as possible again to avoid diversions irrespective of how close you go to other airfields.

The only disadvantage to very long Etops legs is etops fuel build up but this is a small price to pay compared to multiple Etops entry and Exits and many aircraft issues en route causing a diversion and the huge costs involved.

Cheers

 

 

 

 

44 minutes ago, Koen Meier said:

this is what happens when you get a background from one part of the world with a background from another. aviation is filled with these differences.

Fully agree and not only that but a lot of the time like here we are saying the same thing in several cases using different words..lol

[Darren Howie]

To add some more background to a very complex and in depth subject ill split ETOPS(ER OPERATIONS) into three parts.

Etops regulations

Etops planning

Etops cockpit procedures.

Alexander has cover those well above showing that certain systems etc must be fitted to an aircraft and those systems must have adequate coverage o ensure the aircraft is safe for the duration of any flight. IE Fire extinguishers must be suitable for if your on a 120 minutes ETOPS flight they must be able to contain a fire for the full duration of the diversion plus more. This is the main reason for the change in EDTO regulations which limits three and four engine aircraft to threshold times ie max distances from diversion airfields. Again having 4 engines was never restricted like a twin engine ETOPS aircraft however this frequently meant if a cargo fire broke out there would be inadequate time to divert prior to cargo fire protection running out.

Hence not limited by engine capability but EDTO regs mean aircraft like the MD-11 and 747 must have enough fire protection to last at least the length of the longest diversion ie a threhold time that is limited now by fire protection not capability on one engine in the old Etops case.

Planning.

You cant just plan to use ANY airport. Each airport a company uses as an ETOPS adequate must meet all the criteria required by that companies countries regulator.

In short, runway width, length, lights, ATC, fire services, ramp lights, terminal facilities, ability to disembark passengers, customs just to start.

In short when planning the flight dispatch section only have limited airports. The A320 is not runway width restricted but the A321 is and all widebody aircraft in general can only use 45m wide runways. This severely limits runway selections. Going over the Pacific there are very few 45m runways for instance.

Dispatch can generally use lots of adequate airports or minimal adequates.

If your using lots its a logistical effort as you must track weather and airport serviceability continually but it lowers the fuel needed. Less airports means longer diversion legs which means the fuel needed on the most critical leg will be larger. Why is easy your diverting at 10000 generally on two engines which in many cases is the most fuel critical diversion but each flight may be different.

With large fuel reserve requirements a function known as refile can be used where the aircraft from a planning view leaves say on a very long flight from Syd to YVR buts flight plan lists its destination as Seattle instead of YVR. Mid way the flight is refiled to YVR and this way fuel reserves not used in the first section of the flight can now by included to get the aircraft the last bit of the way to YVR. Refile plans are used a LOT on the A320 with its limited fuel capability on long flights. This allows less reserve fuel carriage and more payload.

An Etops flight dispatch course goes for several days covering it here is difficult but i highly recommend the Airbus "getting to grips with ETOPS" document a good read highlighting and expanding this stuff.

Flight Deck Procedures.

This is where things get "different"

First the aircraft needs a specific Etops maintenance inspection and there are several checks done by the flight crew prior to departure ie Fuel Crossfeed check, HF serviceability etc.

Many new pilots get a bit confused re the flight plan versus what we are required to do.

if you can ever find the Emirates ETOPS introduction course it is gold very clearly discussing numerous things clearing the air.

In short the flightplan is generated by the company to legally dispatch the aircraft under ETOPS regulations and aspects are required to be complied with.

For instance we cannot go with less fuel EVER than what the plan says even if your arriving with hours of fuel at your destination as that fuel will be needed in the worst case scenario.

We must respect the Etops entry point where ever it lies and confirm the aircraft is fully serviceable "prior" to crossing it. Not only that but we must establish comms with the company to ensure weather updating, airport updating for closures or anything else is covered.

After crossing the Etops entry point the flight is now operating under ETOPS Procedures. this means if certain systems malfunction an immediate diversion is required. generally a RED LAND ASAP message on the memo overs this plus there are several others which in normal non Etops operations would not require a diversion.

We will be monitoring obviously the aircraft and closely following the fuel state. In the A320 you frequently only might have 100-200kg margin on your critical fuel scenario so close monitoring of fuel is essential. Operating from Australia to New Zealand for many years frequently you if weather was present at destination be extremely tight for fuel. With minimal divert airfields meeting Etops criteria a long last segment means in the worst case ie a depressurization on two engines means you need a large amount of fuel at the final critical point. This means you would land with ample fuel in a normal case but basically zero in the worst case.

How much fuel do you have spare? In the worst case scenario you have enough fuel from the equi time point(critical point) on the last most fuel critical leg to go from cruise level descend to 10000', divert at 10'000 to your divert field then hold for 15 minutes, then fly an approach and your engines will flame out at the end of the landing roll. That is how critical fuel calculation is. Effectively you have 15 minutes spare fuel in this worst case scenario. This is why fuel monitoring is so important.

Where do we divert to? Well your flight plan lists your ETOPS adequate airports however you are not restricted to them! In any inflight emergency you can diver to where ever you want this is always a point of confusion. just because the flight plan says your using these two or three airports does not mean you have to divert there.

In an emergency all bets are off and you go to where you feel you need to.

In many Etops flights given there nature you will divert to one of the listed airports but i cannot emphasize this enough you are not required to. If a more suitable airport for your emergency exists GO THERE!

A classic example of this confusion occurred in Australia several years ago. An Air Asia A330 flying from Melbourne to KL suffered a massive engine failure just prior to its equitime point from Melbourne to its first etops adequate Darwin. This happened to be directly overhead Alice Springs with a huge runway easily capable of taking an A330 in fact over 160 widebody's are in storage there right now including many Air Asia aircraft. The crew shut the engine down then diverted to Melbourne some 800nm away. In the process they overflew numerous airports capable of taking an A330. Why did the crew not land at Alice Springs which was directly below them? The flight plan said the first divert field was Melbourne or Darwin so they followed it.

Your obligations as the Captain for the safe conduct of the flight is always yours and if the aircraft had lost its second engine after by passing at least 8 airports it could safely land at in contravention of Airbus guidelines(RED LAND ASAP means at the nearest suitable airport) is a major issue and the confusion of Etops flight plans being blindly followed is a major industry issue. Many of the better airlines have taken steps to mitigate it now ie pilot training and information.

Because a flightplan says you are using two airports for the segment your in DOES NOT MEAN YOU HAVE TO.

These airports are selected to generate a legal flight plan they at no stage handcuff a crew into what airfield they want to divert to in the event of a failure.

As was discussed above going into ETOPS procedures early has numerous advantages and staying ETOPS as long as you can does as well.

This is why in general airlines operating long segments will only fly one Etops segment as this minimizes flight deck issues doing etops entry checks continually along a single flight. It simplifies procedures, lowers risk of missing an ETOPS compliant requirement and makes like every pilots friend..simple.

As i said this is an extremely complex in depth subject our pilots course i run used to go for 2 days covering everything and even then its not until your in the cockpit that you learn new things which can only really be seen there that regulatory documents simply do not cover.

Im sure other guys will chime in with there experience but Etops is far more complex than simply picking any airport you like a long the way lol.

Hope anyone who reads this finds it helpful!