ETOPS, How Safe Is It?

Lame · Post by **Lame** » 19 Mar 2004, 07:39

In Australia it is always called ETOPS, extended twin operations, some places it is called EROPS, extended range operations.

Also known sometimes as ETOPS, engines turning or passengers swimming.........

Most twin engine Airliners are now approved for these flights, as long as the Operator is also approved, sometimes operating up to 3 hours away from a suitable Airport.

When I did the B767 course at Boeing back in 1980 prior to the introduction of the B767 to Australia, when this ETOPS was very new, our instructor told us the "official" Boeing line, that the odds of one of these engines failing was very high, and in the event of an engine failure, the odds of the engine on the other side failing were massively higher, like millions to one.

However he then told us his personal theory on the odds...... 8O

He said if you are over the middle of the Pacific and one engine fails, remember that the only other engine you have, was made by exactly the same manufacturer, possibly even consecutive serial numbers, probably assembled by exactly the same people as the other engine using the same parts and components.

He said he thought the odds of the other engine failing soon were not good at all. 8O

EBAW_flyer · Post by **EBAW_flyer** » 19 Mar 2004, 08:42

Then it would be the same with a 3-engined aircraft; the other 2 are also similar

. But the thruth is that in almost all cases the engines are not the same age and don't have the same number of cycles.

Lame · Post by **Lame** » 19 Mar 2004, 08:53

It does NOT affect 3 or 4 engined Airliners, the T stands for TWIN (2) engines.

Yes, as I said, this was at the Boeing factory with brand new Aircraft and engines.

Most Airlines, including Ansett at the time, change engines even on new Aircraft to stagger the hours.

However the same still applies, if one GE/Pratt/Roller or whatever fails, you still have only one of the SAME engine left to get you back on the ground. 8O

pilatus · Post by **pilatus** » 19 Mar 2004, 09:11

Well it still is the same for a 3 or 4 engined aircraft. ETOPS means that an aircraft indeed can go more then 1 our from a suitable airport at 1 engine out speed, a more then 2 engine aircraft can go further so the same as ETOPS. The difference is that a 3, 4... engine aircraft must be able to sustain a double engine failure and still be able to make it to a suitable airport. If it cannot it is restricted to 1 hour, the same as a twin. Personaly I think ETOPS is save.

Lame · Post by **Lame** » 19 Mar 2004, 09:18

Sorry, but you are wrong.

ETOPS is EXTENDED TWIN OPERATIONS, by definition it CANNOT apply to anything other than a TWIN.

What you are talking about is EROPS, extended RANGE operations, which applies to 3 and 4 engined (or more) Aircraft.

pilatus · Post by **pilatus** » 19 Mar 2004, 09:45

Yes I know! But the principle is the same. So ones more a 3 or 4...engined aircraft is allowed to go further then 1 hour from a suitable airfield and ETOPS aproves the same for a twin. If you talk about a engine failure it just effects a twin and a more engined aircraft in the same way. ETOPS and EROPS is just the same thing with an other name.

Lame · Post by **Lame** » 19 Mar 2004, 10:01

As I said before, I am sorry, but you are WRONG.

The T in ETOPS indicates twin (or twin engine), it CANNOT mean anything else, no matter how much you want it to.

IF you don't believe me, this is directly off the Boeing web site, or don't you believe the people that make the Aircraft either.

(QUOTE)

Extended-range twin-engine operations (ETOPS) have become common practice in commercial aviation over the last 15 years.

Maintenance and operational programs for the twinjets used in these operations have received special emphasis, and reliability improvements have been made in certain airplane systems. Many operators are now considering the merits of the ETOPS maintenance program for use with non-ETOPS airplanes.

An increasing number of operators are now providing ETOPS service to their passengers. For example, 76 percent of 767 operators and 42 percent of 757 operators are flying ETOPS routes. Several operators have discovered that the cost of ETOPS maintenance, compared to its benefits, also offers them a significant cost advantage when flying their non-ETOPS routes and when operating their non-ETOPS airplanes.

In 1953, the United States developed regulations that prohibited two-engine airplanes from routes more than 60 min (single-engine flying time) from an adequate airport. These regulations were later formalized in U.S. Federal Aviation Administration (FAA) Federal Aviation Regulation 121.161.

The ETOPS program, as outlined in FAA Advisory Circular (AC) 120-42A, allows operators to deviate from this rule under certain conditions. By incorporating specific hardware improvements and establishing specific maintenance and operational procedures, operators can fly extended distances up to 180 min from the alternate airport. These hardware improvements were designed into Boeing 737-600/-700/ -800/-900 and 777 airplanes.

(ENDQUOTE)

I know that there is a language problem here sometimes, but ETOPS really CANNOT mean anything other than a TWO (TWIN) engined Aircraft.

Lame · Post by **Lame** » 19 Mar 2004, 10:21

I just found this on the Internet too.

(QUOTE)

In Europe today EROPS applies, because so it wants our JAA (joint aviation Authority).

In former times in Europe, and also now in the USA, the term is ETOPS still prevailing, which Extended twin operation wants to be called.

The main difference between EROPS and ETOPS is the fact that EROPS is not limited after the name to twin-engine airplanes.

(ENDQUOTE)

Apart from the poor English.

It would appear that the term EROPS is used in Europe, however ETOPS is still used in the USA, and Australia for twins.

So, any Aircraft including a twin, can operate EROPS.

But ONLY a twin can operate ETOPS.

pilatus · Post by **pilatus** » 19 Mar 2004, 11:28

I NEVER said that ETOPS is for not 2 engined aircraft! I just want to reply on your fact that 2 or more engines makes no differnce from your point of view in case of engine failure as you claim that if 1 fails the other will follow. I know that ETOPS is only for twin but the more then 2 engined aircraft are allowed to go further then 1 hour because they have more then 2 engines and just to make it possible to do the same with a twin ETOPS was invented. A company has to prove that they can operate without failures the ETOPS flights and can by doing so get ETOPS of 2,3 and even 4 hours. The only thing I don't agree with is the fact that you claim that if one engine fails the other will probably fail also as it was made by the same constructor and people.

Lame · Post by **Lame** » 19 Mar 2004, 11:39

I give up, I only speak English, and I do not understand what you are on about.

Maybe someone could translate into English for me?

You said ETOPS is the same as EROPS, and it is NOT.

I do not know what you are talking about?

IF you don't believe me, or Boeing, what else can I do.

Avro · Post by **Avro** » 19 Mar 2004, 11:52

Your right about ETOPS and EROPS Lame, but that's not what pilatus is trying to say in his last post.

From what I understands, pilatus doesn't agree with you on the "when one engine fails the other will follow" statement.

Here's my thought:

You could indeed think that when one engine fails the other could follow since it's the same constructor and the same engine, but the probablility is still very small.
If it should be a design fault that causes the engine to fail I would totally agree with you Lame.

Greetz
Chris
8)

Lame · Post by **Lame** » 19 Mar 2004, 12:03

Thank you.

He was saying that they were the same thing, and they are NOT.

I did NOT say that the other will follow, I tried to explain, this was the personal thoughts of the instructor at Boeing.

Odds of things happening are a funny business, like this old joke.

Aunt Bessie loved to visit her nieces and nephews. However, she had relatives all over the country.

The problem was that no matter how much she enjoyed seeing them, she hated flying. No matter how safe people told her it was, she was always worried that someone would have a bomb on the plane.

She read books about how safe it was and listened to the stewardess demonstrate all the safety features. But she still worried herself silly every time a visit was coming up.

Finally, the family decided that maybe if she saw the statistics she'd be convinced. So they sent her to a friend of the family who was an actuary.

"Tell me," she said suspiciously, "what are the chances that someone will have a bomb on a plane?"

The actuary looked through his tables and said, "A very small chance. Maybe one in five hundred thousand."

She nodded, then thought for a moment. "So what are the odds of two people having a bomb on the same plane?"

Again he went through his tables.

"Extremely remote," he said. "About one in a billion."

Aunt Bessie nodded and left his office.

And from that day on, every time she flew, she took a bomb with her.

8O

Avro · Post by **Avro** » 19 Mar 2004, 12:08

I did NOT say that the other will follow, I tried to explain, this was the personal thoughts of the instructor at Boeing

Of course, sorry. That's what I meant

That's a very good joke Lame

Chris

Lame · Post by **Lame** » 19 Mar 2004, 12:19

Okay.

It is very difficult sometimes with all the different "types" of English.

Off to bed now, good night............

MD-11 · Post by **MD-11** » 19 Mar 2004, 14:30

Lame wrote: if one GE/Pratt/Roller or whatever fails, you still have only one of the SAME engine left to get you back on the ground. 8O

You'll always get back on the ground...

Gravity you know, what goes up must come down.

Lame · Post by **Lame** » 19 Mar 2004, 20:08

What is it with people here.

Okay I should have said "back on the ground safely"

So many people here do not contribute anything to the discussion, just pick on what people say.

Then again if you are going to be that picky, you are wrong anyway, what if you are over water, you will always come back to "earth", not necessarily "ground".

Avro · Post by **Avro** » 19 Mar 2004, 20:46

Lame,

I'm sure MD-11 didn't ment that seriously at all, it was a funny statement. That's why he had put the

Chris

MD-11 · Post by **MD-11** » 19 Mar 2004, 21:32

Avro wrote:Lame,

I'm sure MD-11 didn't ment that seriously at all, it was a funny statement. That's why he had put the

Chris

Avro took the words right out of my mouth.

About ETOPS, already flew 2 times on an ETOPS flight to MIA.
I don't have any problems with twin engines over water.
@ Lame, indeed just kidding.

Lame · Post by **Lame** » 19 Mar 2004, 21:49

Okay, however I still think it is a problem here on Luchtzak.

I enjoy this site most of the time, it is great.

However like what happened to new member sidestick_rules yesterday, when he asked about something on the A320, you get people who do not answer the question or contribute to the discussion, but pick fault with the topic or the English in it.

I find this astonishing, especially on a site where the majority of people (through no fault of their own) are not that conversant in English.

Lame · Post by **Lame** » 20 Mar 2004, 09:35

Of course with all the latest technology, plus ETOPS requirements, you would have to be having a really bad day to lose both engines on a twin,

IF it happened it would more likely be something like volcanic ash, or a fuel problem common to both engines.

For many years up until only a few years ago, I looked after a couple of DC9 Freighters here in Brisbane.

They were well maintained, but NOT to ETOPS as such.

We used to fly not only all around Australia and PNG, but also well out into the Pacific, mainly hundreds of trips to Honiara to pick up tuna, and bring it back to Cairns.

Alhough they were freighters, not pax aircraft, as I said they were not ETOPS compliant, yet we never in all that time lost one engine, let alone two.

There were also no special preflights checks or anything, just off we went.

We went right out to Nauru one day, and had to talk to Honolulu Control (or Honolulu Centre I cannot remember which?), when they asked for our SELCAL and we told them we didn't even have one (which we didn't), I don't think they believed us.

They asked why were you Aussies out there so far from land, in a non ETOPS twin, and not even any SELCAL. 8O