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3 And 4 Engine Planes Requiring Etops  
User currently offlineVikingA346 From Sweden, joined Oct 2006, 515 posts, RR: 0
Posted (4 years 11 months 6 days 15 hours ago) and read 8992 times:

I have been exploring this topic for a week or so now with the possibility of writing my MSc thesis on this topic. Can any experts please share your expertise on this topic? I know the FAA has proposed that 3 and 4 engine jets be required to follow ETOPS guidelines just like twins are today. When is this due to be voted on? What are some of the implications of making this a requirement for tri and quad jets?

Many thanks


...you will walk the earth with your eyes turned skyward, for there you have been and there you shall return
36 replies: All unread, showing first 25:
 
User currently offlineLaddie From United States of America, joined Jan 2010, 625 posts, RR: 8
Reply 1, posted (4 years 11 months 6 days 11 hours ago) and read 8929 times:

Did you find this PowerPoint presentation by the FAA dated June 2008?
http://www.faa.gov/news/conferences_...onference/media/US_ETOPS_Final.ppt

Page 10 and on has info about 3- and 4-engine Extended Operations.

If the link doesn't work, then go to www.faa.gov, type ETOPS in the search box, and then look for a file named "Looking to the Future" in the search results.


User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80
Reply 2, posted (4 years 11 months 6 days 9 hours ago) and read 8890 times:



Quoting VikingA346 (Thread starter):
I know the FAA has proposed that 3 and 4 engine jets be required to follow ETOPS guidelines just like twins are today. When is this due to be voted on?

It's not voted. The FAA proposes the rule, takes comments, and then issues the final rule. The new regulations were published 16-Jan-2007.
http://www.faa.gov/other_visit/aviat...all_infos/media/2007/info07004.pdf

Quoting VikingA346 (Thread starter):
What are some of the implications of making this a requirement for tri and quad jets?

Primarily, changes to maintenance practices and dispatch planning re: diversion airports.

Tom.


User currently offlineWeb500sjc From United States of America, joined Sep 2009, 752 posts, RR: 0
Reply 3, posted (4 years 11 months 6 days 7 hours ago) and read 8849 times:
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How about LROPS, I heard that this might be a replacment to all aircraft flying ETOPS like missions, except with no limit on the amount of engines. Can anybody bring to light what that might mean?

first post!



Boiler Up!
User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80
Reply 4, posted (4 years 11 months 6 days 7 hours ago) and read 8833 times:



Quoting Web500sjc (Reply 3):
How about LROPS, I heard that this might be a replacment to all aircraft flying ETOPS like missions, except with no limit on the amount of engines. Can anybody bring to light what that might mean

It's more the other way...LROPS got replaced by ETOPS. LROPS was ETOPS for more-than-twins. Now that the FAA drove ETOPS onto all aircraft, it's functionally displaced LROPS.

Quoting Web500sjc (Reply 3):
first post!

Welcome aboard!

Tom.


User currently offlineWeb500sjc From United States of America, joined Sep 2009, 752 posts, RR: 0
Reply 5, posted (4 years 11 months 6 days 4 hours ago) and read 8792 times:
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thanx, so get it straight, the FAA put ETOPS restrictions on all airliners, not just twinjets.


Boiler Up!
User currently online747classic From Netherlands, joined Aug 2009, 2231 posts, RR: 14
Reply 6, posted (4 years 11 months 5 days 21 hours ago) and read 8693 times:

IMO it's a politic driven FAA ruling in favor of twins and against 3 and 4 engined aircraft, as not many American airlines are flying passengers with these aircraft anymore.(only UA and DL (ex NWA) with 747-400's).
Many Non US airlines are operating large quantities of these aircraft.(A380, A340, 747), so why would the EASA or JAA or other countries agree with this proposed rule making.
The costs of complying with the new fire suppression and oxygen requirements for 3 and 4 engined aircraft would be carried for 99% by Non US countries.

The "hidden" , far more important, change possible under the newly proposed ruling, is to extend the current 180 min ETOPS to go any length and any duration from an alternate airport, subject to the capabilities of the aircraft.
In other words : to extend the operation of twins in all remote (Polar, oceanic) area's of the world, in fact the entire world.

IMO, this "hidden" part is another victory of Economy over Safety in aviation.

See also :
http://www.flightglobal.com/articles...frees-twins-from-etops-limits.html



Operating a twin over the ocean, you're always one engine failure from a total emergency.
User currently offlineVikingA346 From Sweden, joined Oct 2006, 515 posts, RR: 0
Reply 7, posted (4 years 11 months 5 days 13 hours ago) and read 8554 times:

OK, I didn't know it was in practice already.

Have other countries adopted this as well? I assume this only applies to U.S. registered carriers.....



...you will walk the earth with your eyes turned skyward, for there you have been and there you shall return
User currently offlineOldAeroGuy From United States of America, joined Dec 2004, 3606 posts, RR: 66
Reply 8, posted (4 years 11 months 5 days 11 hours ago) and read 8512 times:

Quoting Web500sjc (Reply 5):
thanx, so get it straight, the FAA put ETOPS restrictions on all airliners, not just twinjets.

More accurately, ETOPS rules where put in place for Tris and Quads when opearting more than 180 minutes from a suitable airport.

Quoting Tdscanuck (Reply 2):
Primarily, changes to maintenance practices and dispatch planning re: diversion airports.

Also insures that Tris and Quads carry appropriate fire suppression and oxygen so that a suitable airport can be reached.

Quoting VikingA346 (Reply 7):
Have other countries adopted this as well? I assume this only applies to U.S. registered carriers.....

CASA (the Australian equivalent of the FAA) have adopted similar regulations known as EDTO.

http://74.125.95.132/search?q=cache:...CASA+EDTO&cd=2&hl=en&ct=clnk&gl=us

Quoting 747classic (Reply 6):
The "hidden" , far more important, change possible under the newly proposed ruling, is to extend the current 180 min ETOPS to go any length and any duration from an alternate airport, subject to the capabilities of the aircraft.
In other words : to extend the operation of twins in all remote (Polar, oceanic) area's of the world, in fact the entire world.

IMO, this "hidden" part is another victory of Economy over Safety in aviation.

Prior to this ruling, it was perfectly legal for a Tri or Quad to fly a route that included a point 180 minutes or more from a suitable airport with cargo hold fire suppression material sufficient for a shorter diversion distance. While most operators carried the appropriate amount of fire suppression material, there was no regulatory requirement for them to do so.

With the adoption of the new ETOPS standards, all airplanes (Twins, Tris and Quads) will be required to carry fire suppresion capability appropriate to the mission being flown.

This would appear to be a victory for Safety over Economy.

Quoting 747classic (Reply 6):
The costs of complying with the new fire suppression and oxygen requirements for 3 and 4 engined aircraft would be carried for 99% by Non US countries.

Do you feel that it's appropriate to have less fire suppression material onboard than would be required for a possible diversion distance?

[Edited 2010-01-26 14:55:07]


Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
User currently offlinePolymerPlane From United States of America, joined May 2006, 991 posts, RR: 3
Reply 9, posted (4 years 11 months 5 days 11 hours ago) and read 8499 times:



Quoting 747classic (Reply 6):

How is it requiring a quad to comply with a regulation that makes flight safer is "another victory of Economy over Safety in aviation"?

The difference between quad and twin is just the engine, but for ETOPS you subject the plane to a much stringent requirement such as the fire suppression and oxygen.

Do you think fire only happens in twin cargo hold vs. quad?



One day there will be 100% polymer plane
User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80
Reply 10, posted (4 years 11 months 5 days 9 hours ago) and read 8463 times:



Quoting 747classic (Reply 6):
Many Non US airlines are operating large quantities of these aircraft.(A380, A340, 747), so why would the EASA or JAA or other countries agree with this proposed rule making.

Because ETOPS procedures proved to be extremely effective at reducing IFSD's, which is a good thing on all aircraft, regardless of how many engines they've got. And, as noted in several posts above, your cargo hold fire and/or ECS system failure has no idea how many engines you've got, so it never really made sense that twins had to carry more stringent and safer levels of O2 and fire suppression.

Tom.


User currently online747classic From Netherlands, joined Aug 2009, 2231 posts, RR: 14
Reply 11, posted (4 years 11 months 5 days ago) and read 8413 times:

Quoting 747classic (Reply 6):
IMO, this "hidden" part is another victory of Economy over Safety in aviation

As stated above, I referred only to the more relaxed way of granting even more extended twin operations over very remote area's in the world under this new regulation. And if you read the new rules very good, it's almost impossible to get your airline ETOPS qualification revoked.

Quoting OldAeroGuy (Reply 8):
With the adoption of the new ETOPS standards, all airplanes (Twins, Tris and Quads) will be required to carry fire suppression capability appropriate to the mission being flown.

I agree, that's the good part. All aircraft have to be treated equally.
However the start of the introduction of the proposed ruling was very clever. It was started when the battle between the 777 and the A340 was at his peak. They very well knew that a lot comments would come from (foreign) operators with 3 or 4 engined aircraft.( surprisingly almost no American airlines.) . So all the (media) attention was shifted to that part, the more relaxing rules of the twin operation were "forgotten".
After a lot of discussions the initial proposed 3 and 4 engined aircraft rules were relaxed more and more (grandfather rights of earlier certificated aircraft granted, etc).
But the relaxing rule making of the twin operation was largely overseen.

That's why I called it "Another victory of Economy over Safety".

P.S. In what kind of aircraft would you prefer to fly over a very remote area :
B787, with 2 GEnx-1B engines or the 747-8I, with 4 GEnx-2B engines, both with the same fire suppression and oxygen rules.

For more background info :
http://rgl.faa.gov/Regulatory_and_Gu...6717586257266005f3b91!OpenDocument

[Edited 2010-01-27 01:30:43]

[Edited 2010-01-27 02:22:29]


Operating a twin over the ocean, you're always one engine failure from a total emergency.
User currently offlineOldAeroGuy From United States of America, joined Dec 2004, 3606 posts, RR: 66
Reply 12, posted (4 years 11 months 3 days 20 hours ago) and read 8299 times:



Quoting 747classic (Reply 11):
B787, with 2 GEnx-1B engines or the 747-8I, with 4 GEnx-2B engines, both with the same fire suppression and oxygen rules.

Either one would be fine with me. Driving to the airport presents a far higher risk.



Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
User currently online747classic From Netherlands, joined Aug 2009, 2231 posts, RR: 14
Reply 13, posted (4 years 11 months 3 days 18 hours ago) and read 8265 times:



Quoting OldAeroGuy (Reply 12):
Driving to the airport presents a far higher risk.



I fully agree on that one!

Quoting OldAeroGuy (Reply 12):
Either one would be fine with me



In this respect our views differ, but that's one of the foundations of this forum.
I prefer the four holer, applying a little rudder trim, descend 2000 or 4000ft, still above the weather and proceed to your alternate or if possible your destination.
On the twin, IMO 330 minutes to your first alternate on one engine is a very long time, with a lot of stress on the flight-deck..



Operating a twin over the ocean, you're always one engine failure from a total emergency.
User currently offlineVikingA346 From Sweden, joined Oct 2006, 515 posts, RR: 0
Reply 14, posted (4 years 11 months 3 days 18 hours ago) and read 8260 times:



Quoting 747classic (Reply 13):
On the twin, IMO 330 minutes to your first alternate on one engine is a very long time, with a lot of stress on the flight-deck..

I most certainly agree. 5 hours is a helluva long time for the crew to sweat the loss of one engine. Although the chance of an IFSD happening in the first place is small, the chance it happens at the critical point is incredibly low, I would rather be on a quad jet and losing one engine with a 5 hour diversion ahead.

Luckily, there are (AFAIK) no routes in the world that require 330 minute ETOPS. SYD-EZE comes close, and is certainly over 240 minutes according to the great circle distance. EZE-AKL is also up there, but other than that, I can only think of SYD-JNB surpassing 240 minutes, none of which are done with twin-jets.

Anyone know what the highest ETOPS requirement is for a current twin operating a current route?



...you will walk the earth with your eyes turned skyward, for there you have been and there you shall return
User currently offlineTimz From United States of America, joined Sep 1999, 6903 posts, RR: 7
Reply 15, posted (4 years 11 months 3 days 15 hours ago) and read 8227 times:

In the past, people here have said QF doesn't allow any of its flights south of 60 S. Is that still true?

Are any twins currently scheduled LAX-PPT? If so, they still have to dogleg to stay within range of Hawaii? One Flightaware flight plan a few years ago showed a NZ 767 reaching 1275 nm from Hilo.


User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80
Reply 16, posted (4 years 11 months 3 days 13 hours ago) and read 8201 times:



Quoting 747classic (Reply 11):
So all the (media) attention was shifted to that part, the more relaxing rules of the twin operation were "forgotten".

What relaxing? If you want to do 330-minute ETOPS you've got *more* requirements, not less.

Quoting 747classic (Reply 11):
P.S. In what kind of aircraft would you prefer to fly over a very remote area :
B787, with 2 GEnx-1B engines or the 747-8I, with 4 GEnx-2B engines, both with the same fire suppression and oxygen rules.

The 787, hands down. Aircraft certification has come a *long* way since the 747 was first certified. Although both aircraft are perfectly safe, the 747 has a lot more grandfathered certification than the 787.

Quoting 747classic (Reply 13):
On the twin, IMO 330 minutes to your first alternate on one engine is a very long time, with a lot of stress on the flight-deck..

Yes, it's a long time, which is exactly why this exact scenario is tested over (and over and over and over) before the engine ever gets on the plane, and again before the plane ever enters service.

Tom.


User currently offlineSunriseValley From Canada, joined Jul 2004, 5225 posts, RR: 5
Reply 17, posted (4 years 11 months 2 days 22 hours ago) and read 8114 times:



Quoting Timz (Reply 15):
In the past, people here have said QF doesn't allow any of its flights south of 60 S. Is that still true?

The regulator does not permit it according to the recently adopted EDTO standard

Are any twins currently scheduled LAX-PPT? If so, they still have to dogleg to stay within range of Hawaii? One Flightaware flight plan a few years ago showed a NZ 767 reaching 1275 nm from Hilo.
[/quote]
NZ had to fly around to meet the 180min diversion when they flew PPT-LAX with the 767. They might still have a minor fly around on the RAR-LAX route. I must look at a flight plan on Flightaware.


User currently offlineHiFi From Brazil, joined Apr 2005, 192 posts, RR: 0
Reply 18, posted (4 years 11 months 2 days 11 hours ago) and read 8045 times:



Quoting Tdscanuck (Reply 16):
Quoting 747classic (Reply 11):
P.S. In what kind of aircraft would you prefer to fly over a very remote area :
B787, with 2 GEnx-1B engines or the 747-8I, with 4 GEnx-2B engines, both with the same fire suppression and oxygen rules.

The 787, hands down. Aircraft certification has come a *long* way since the 747 was first certified. Although both aircraft are perfectly safe, the 747 has a lot more grandfathered certification than the 787.

Not only that, let's not forget that the 747 was designed to fly safe with 1 engine failure, but not 2 or 3.. The fact that it's got 4 engines does not mean that losing the necessary thrust it needs to fly is less probable than with 787's 2 engines.. it's 1 engine failure in either case.



no commercial potential
User currently online747classic From Netherlands, joined Aug 2009, 2231 posts, RR: 14
Reply 19, posted (4 years 11 months 2 days ago) and read 7968 times:

Quoting HiFi (Reply 18):
Not only that, let's not forget that the 747 was designed to fly safe with 1 engine failure, but not 2 or 3.. The fact that it's got 4 engines does not mean that losing the necessary thrust it needs to fly is less probable than with 787's 2 engines.. it's 1 engine failure in either case.



I flown a lot of hours (in the 747 full flight simulators) on only 2 engines (worst case, one side 2 failed engines.) with the 747. The aircraft is fully controllable in all flight regimes, but the altitude is more restricting depending aircraft weight. The only thing to watch carefully is the VMC air. Even with 3 engines out on the approach it's possible to make a landing. (no Go around possible), however this is very demanding and you have only one opportunity.
The two engine-out landing technique had to be shown by the PIC (Captain) at least one time a year during the proficiency checks on the simulator with the airlines I was working.

So, with the same engines installed on the 747 and the the 787 i prefer the 747 in remote area's with no close by alternate. The probability of two engines failing on both aircraft is very rare, but you can limb back to your alternate destination with the 747 and not with the 787.

Quoting Tdscanuck (Reply 16):
Quoting 747classic (Reply 11):
P.S. In what kind of aircraft would you prefer to fly over a very remote area :
B787, with 2 GEnx-1B engines or the 747-8I, with 4 GEnx-2B engines, both with the same fire suppression and oxygen rules.

The 787, hands down. Aircraft certification has come a *long* way since the 747 was first certified. Although both aircraft are perfectly safe, the 747 has a lot more grandfathered certification than the 787.



The 747-8 will be certified with grandfather rights, but it will be equally safe than the 787. All new and several old features will be looked at and if necessary re-certificated.
On top of this the 747-8 has the advantage that it's a proven airframe, all the "weak" spots are already known and corrected., only the engines are new , but there are 4 installed.
The 787 is a new airframe, with new materials and new engines and from day one ETOPS certified.

[Edited 2010-01-30 02:42:19]


Operating a twin over the ocean, you're always one engine failure from a total emergency.
User currently offlineSunriseValley From Canada, joined Jul 2004, 5225 posts, RR: 5
Reply 20, posted (4 years 11 months 1 day 19 hours ago) and read 7930 times:



Quoting VikingA346 (Reply 14):
Luckily, there are (AFAIK) no routes in the world that require 330 minute ETOPS. SYD-EZE comes close, and is certainly over 240 minutes according to the great circle distance.

If the flight plan below is typical QF are not flying it along the great circle. Interestingly they did go a little south of 60degrees.
Plot the route on GC Mapper and you will see how it jogged a little across the ocean.

Here is a transcript of the real-world route taken by VH-OEJ on her first flight to SAEZ:

YSSY OPTIC TONIM S44 E160 S45 E160 S48 E163 S50 E165 S55 E170 S58 E175 S60 E180 S61 W175 S62 W170 S63 W165 S63 W160 S63 W155 S63 W150 S63 W145 S63 W140 S63 W135 S63 W131 S62 W125 S61 W120 S60 W115 S59 W110 S58 W105 S56 W100 S54 W95 S52 W90 S49 W85 S47 W82 S46 W080 S43 W75 MON UB682 BAR UW68 BODIR EZE SAEZ

link...http://www.curbe.com/QVA/qva/flightline.htm#Route


User currently offlineEGTESkyGod From United Kingdom, joined Jun 2005, 1712 posts, RR: 12
Reply 21, posted (4 years 11 months 1 day 10 hours ago) and read 7831 times:
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I'm baffled how Extended TWIN Ops applies to 'conventional' quads but if it's just about stricter guidelines then why don't they just say that?! EQUOPS or something...

Having said that, interestingly enough Concorde had to meet ETOPS guidelines due to how close each pair of engines were to each other.



I came, I saw, I Concorde! RIP Michael Jackson
User currently offlineTimz From United States of America, joined Sep 1999, 6903 posts, RR: 7
Reply 22, posted (4 years 11 months 1 day 9 hours ago) and read 7826 times:



Quoting EGTESkyGod (Reply 21):
Concorde had to meet ETOPS guidelines

How many minutes? How many miles did that correspond to? Would they calculate the allowed radius using one-engine-out speed or two-engine-out?


User currently offlineEGTESkyGod From United Kingdom, joined Jun 2005, 1712 posts, RR: 12
Reply 23, posted (4 years 11 months 1 day 7 hours ago) and read 7790 times:
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Quoting Timz (Reply 22):
How many minutes? How many miles did that correspond to? Would they calculate the allowed radius using one-engine-out speed or two-engine-out?

Um... not a clue, that's probably one for GDB. At 21 miles per minute in supercruise for over two hours? 2600 miles in two hours... Engine questions? I'll have to pass...



I came, I saw, I Concorde! RIP Michael Jackson
User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80
Reply 24, posted (4 years 11 months 1 day 5 hours ago) and read 7772 times:



Quoting EGTESkyGod (Reply 21):
I'm baffled how Extended TWIN Ops applies to 'conventional' quads

It doesn't. But ETOPS, at least as far as the FAA is now concerned, doesn't stand for Extended Twin Operations, it stands for Extended Operations.
http://www.faa.gov/other_visit/aviat...all_infos/media/2007/info07004.pdf
"This InFO announces the publication of new regulations on Extended Operations (ETOPS) and explains some of the major revisions and additions to current ETOPS guidance."

Quoting EGTESkyGod (Reply 21):
but if it's just about stricter guidelines then why don't they just say that?!

They do. See the link above.
"Note that the changes can be characterized by the change in meaning of ETOPS to “Extended Operations” since these provisions have broadened to include aircraft with more than two engines and to include both part 121 and part 135 operations."

Tom.


25 TristarSteve : But the B747-8 could not be certificated without grandfather rights. There is no door at the front of First Class. There is no door at the front of t
26 747classic : Thanks Tom, for high-lighting this article. So under the new ETOPS (extended operation) rule for all aircraft (except freighters with more than two e
27 Tdscanuck : I can see the critical fuel scenario change being considered this way, although the fact that it now applies to all aircraft, not just twins, is prob
28 SunriseValley : Also it requires that the operators maintain to higher standards. Engines come off the wing at lower hours. All this costs money and must surely be a
29 Mrocktor : No, it is a policy reacting to the fact that twins have become safer than 3 and 4 holers when operated far from a diversion airport. Quite the contra
30 UAL747 : Well, I can agree with you that it looks suspiciously political and pro-Boeing twins. HOWEVER, virtually ALL LROPS routes are to/from the US, especia
31 747classic : But on a quad on N-2 at this point you have hours of flying time remaining before you run out of fuel. The alerted rescue team(s) can already fly tow
32 SunriseValley : 747classic..........not me, you have attributed someone else's statement incorrectly
33 747classic : I am sorry, SunriseValley. I accidently activated the "selected text quoted" on reply 28 iso reply 29., i scrolled a little bit to far. I was replyin
34 HiFi : OK, I'll agree with you there. However, in terms of safety margins, you are not taking into consideration that on a quad your probability of a dual e
35 HiFi : Hahaha.. I'm sorry SunriseValley, I seem to have committed the same mistake as 747classic!
36 OldAeroGuy : Isn't that what I said?
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