2122M
Posts: 1095
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 7:26 pm

flyingclrs727 wrote:
2122M wrote:
JackMeahoff wrote:
I like the ocean liner analogy. Cruise ships don't cross oceans, ocean liners do. More heavily built, higher bow, fewer windows near the water line, etc. The 737 was designed to be a regional jet, not a long range transoceanic jet.


Cruise Ships regularly do oceanic crossings. Just a quick search found me the 30 Tonne Seabourn Sojourn doing a 56 day San Diego to Australia cruise later this month. It happens all the time. Looks at Windstar trans-Atlantic cruises.

I know that's not the point of this thread, but worth pointing out the error.


Don't you mean 32,000 tonne or 32K tonne?


Sure did. My bad.

Either way, that's very small by cruise ship standards.
 
GalaxyFlyer
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 7:39 pm

The advantage of three or four engines is, in the event of one engine loss, the flight MAY be continued on two or three, respectively. Engine loss on a twin, any twin, is a diversion to the nearest suitable airport. This is one of the primary operational reasons for the VC planes (AF1) being quads; they don’t want to divert or make an emergency landing without the protocols accomplished.

Yes, every overwater/remote flight has to plan for the three events, regardless of engines. The tri/quads also have to plan for the route at both one- and two-engine loss for minimum terrain and fuel. Twins have to plan for OEI diversion accounting for terrain. This is done every flight.

GF
 
Western727
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 8:00 pm

barney captain wrote:
Western727 wrote:
barney captain wrote:

No, I meant GEG - although Rio is more appealing. It was a new delivery that came from Boeing with full fuel - for a 38 minute flight to the paint shop in GEG. It was to be the first Heart One livery, although it was still green for this flight.


You got my curiosity piqued. Why would anyone want to fill the tanks for a quick hop to the paint shop? GEG is by no means a remote airport with limited services.

...Or is it SOP to fill the tanks on delivery like I'm starting to suspect now?


I think it's a "gift" from Boeing for new aircraft - at least that's what we were told. I don't know if it's SOP, but we certainly didn't want that much fuel. The a/c was delivered form RNT to PAE, where it had wifi and a few other mods done, then we ferried it to GEG for paint. The irony of full tanks for a 38 min flight with only two pilots wasn't lost on us. The double irony is that (according to the pain shop at least) they have to defuel the a/c prior to paint.


Fascinating. I appreciate the details, BC. I'm only a private pilot, but my FBO's policy on its rentals is to fill up the avgas to the tabs only (e.g., on the PA-28-160/180/181 that's 17 gal, out of a useful capacity of 24 gal per tank) upon return from a trip, so that the next pilot will then have that wiggle room should they decide to take, say, 3 pax on one of the PA-28s with only 160 hp (usable load is about 870 lbs, so that naturally becomes very important). It seems odd that provisions aren't in place to allow for only the needed fuel on delivery at Boeing when appropriate.

EDIT: clarification.
Jack @ AUS
 
ThePinnacleKid
Posts: 530
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 8:44 pm

rbavfan wrote:
ThePinnacleKid wrote:
Cubsrule wrote:

How is any of what you cited different on a 757 or widebody twin from on a 737 or 320? While the larger aircraft have more range, carriers don’t fill up the tanks just for the sake of helping passengers sleep better at night. To the extent that uncontained engine failures are some sort of systemic problem (which is debatable at best), note that they generally do not occur hours into cruise.


I can comfortably answer an aspect of this part cubs... having flown the ERJ and now the 767... both can obviously bang an engine and comfortably fly on the one remaining engine... the ERJ though has a much lower SE cruising altitude than the 767... I imagine, that in this case... that may in fact be what the poster was implying as to preference to avoid 737/320 family on long ETOPS flights.... As for myself.. knowing how the 767 was designed specifically with extended overwater operations in mind, like other large twins... vs the 737 which is not.. I also would pick an old WB over the new 73's any day on the Hawaii run.... Hawaii is a true ETOPS 180 run... much more critical than flying the Atlantic for example. While a poster above is correct.. both are certified to have it all go bad at the worst spot, drop down, and keep trucking, I still would rather be on the one that was designed for the mission over the one that inherited the mission.

As to an actual operational numbers... yesterday in the 763 on a transcon run, our midpoint SE ability (nearing the rockies) had a drift down altitude of FL301 still.... we had just over 55k lbs payload and 40k fuel still on board at that point... I don't know how the 737 numbers actually stack up in a similar situation... but someone else here who has a type in that might be able to expand on that airframes capabilities.



The 767 was not designed specifically for ETOPS. It was designed for domestic use based on a United Airlines requirement. The ETOPS was created later after TWA started flights TATL flights to Europe. When started they had to fly a more northerly route and once engine performance meet better specs it was upgraded to allow 120 & then 180. First flights went over Canada, Greenland & Iceland to meet safety requirements at the time. This is well covered in old issues of Aviation Week & Air transport world and other magazines in the early to late 80's. TWA was the airline that pushed for it.



Never said it was specifically for ETOPS... I said it was specifically with extended overwater operations IN MIND.... which it was... It was designed in tandem with the 757 with the distinct characteristics to be fuel efficient with mid range and mid capacity runs... and it was first deployed on domestic and transcon runs because planes didn't start with ETOPS back then... the first variants didn't have the range to effectively do it on the "blue spruce runs" (efficiency wise)... but you are absolute on point with the development and who and when.... I can also say a lot here in this thread focus so so so much on the ETOPS being the engine thing... it's not. So much goes into an aircraft flying ETOPS runs and there is more than just engine reliability. I stand by the fact I would prefer a wide body or 757 vs a 737/A320 on the Hawaii run... look at the levels of redundancies of systems on a 767 vs a 737, A320, ERJ. All airliners are highly reliable and redundant.. some just go a step further. I never truly realized how over the top redundant some aircraft were until I got my 75/76 type rating. The plane is a beast and a joy to fly.
"Sonny, did we land? or were we shot down?"
 
stratclub
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 8:50 pm

catiii wrote:
nine4nine wrote:
767333ER wrote:
What you have to ask yourself is how long this type of engine has been in service and how much use in total such as hours have been put on it. Just because one operator has had some trouble for whatever reason doesn’t mean the engine is suddenly unsafe if everyone else’s is fine still.


No, but given range issues due to fuel I wouldn’t feel comfortable being down an engine and flying lower altitude with higher fuel burn or even the added drag. I’d imagine any issue on a mainland-Hawaii flight to the likes of the WN issue would have resulted in a major tragedy.

I will never book a Hawaii flight personally on an 320/321 or 737. Have heard stories about planes arriving on fumes after stronger than expected headwinds. Couple that with an engine issue. I think it’s a disaster in the making.


"Fumes?" My gosh, this post takes the hyperbole on this site to a whole new level.

Enlighten us, where did you hear about these potential catastrophes?

Being that Jet A has a flash point of 100F degrees, where exactly do these alleged "fumes" come from? Most likely what should have been quoted was that the aircraft(s) in question dipped into their reserves.
 
Cubsrule
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 8:59 pm

ThePinnacleKid wrote:
rbavfan wrote:
ThePinnacleKid wrote:

I can comfortably answer an aspect of this part cubs... having flown the ERJ and now the 767... both can obviously bang an engine and comfortably fly on the one remaining engine... the ERJ though has a much lower SE cruising altitude than the 767... I imagine, that in this case... that may in fact be what the poster was implying as to preference to avoid 737/320 family on long ETOPS flights.... As for myself.. knowing how the 767 was designed specifically with extended overwater operations in mind, like other large twins... vs the 737 which is not.. I also would pick an old WB over the new 73's any day on the Hawaii run.... Hawaii is a true ETOPS 180 run... much more critical than flying the Atlantic for example. While a poster above is correct.. both are certified to have it all go bad at the worst spot, drop down, and keep trucking, I still would rather be on the one that was designed for the mission over the one that inherited the mission.

As to an actual operational numbers... yesterday in the 763 on a transcon run, our midpoint SE ability (nearing the rockies) had a drift down altitude of FL301 still.... we had just over 55k lbs payload and 40k fuel still on board at that point... I don't know how the 737 numbers actually stack up in a similar situation... but someone else here who has a type in that might be able to expand on that airframes capabilities.



The 767 was not designed specifically for ETOPS. It was designed for domestic use based on a United Airlines requirement. The ETOPS was created later after TWA started flights TATL flights to Europe. When started they had to fly a more northerly route and once engine performance meet better specs it was upgraded to allow 120 & then 180. First flights went over Canada, Greenland & Iceland to meet safety requirements at the time. This is well covered in old issues of Aviation Week & Air transport world and other magazines in the early to late 80's. TWA was the airline that pushed for it.



Never said it was specifically for ETOPS... I said it was specifically with extended overwater operations IN MIND.... which it was... It was designed in tandem with the 757 with the distinct characteristics to be fuel efficient with mid range and mid capacity runs... and it was first deployed on domestic and transcon runs because planes didn't start with ETOPS back then... the first variants didn't have the range to effectively do it on the "blue spruce runs" (efficiency wise)... but you are absolute on point with the development and who and when.... I can also say a lot here in this thread focus so so so much on the ETOPS being the engine thing... it's not. So much goes into an aircraft flying ETOPS runs and there is more than just engine reliability. I stand by the fact I would prefer a wide body or 757 vs a 737/A320 on the Hawaii run... look at the levels of redundancies of systems on a 767 vs a 737, A320, ERJ. All airliners are highly reliable and redundant.. some just go a step further. I never truly realized how over the top redundant some aircraft were until I got my 75/76 type rating. The plane is a beast and a joy to fly.


What redundancies do the 75/76 have that, say, a 321NEO lacks?
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Aviano789
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:01 pm

Max Q wrote:
joeycapps wrote:
I'm a little confused, and I'll admit I didn't read every single response on this thread, but I just want to clarify something... The aircraft and its engines don't know they're ETOPS. ETOPS doesn't make the aircraft fly over an ocean; it certifies it. There's a huge difference.

LAX-HNL is about ~2,550mi and LAX-JFK is about ~2,450 miles, per GCM. I assure those of you panicked about flying a twin across the ocean that the aircraft chosen to fly the route is qualified to fly at least that amount, and more, irrespective of what it's flying over. I'd love nothing more than to sip a drink on the upper deck of a Pan Am 747 back in "the day" for nostalgia, but truth be told, I'll take today's advancements in aviation any day of the week, and twice on Sundays. If your plane is going to plummet - as some fear - it doesn't matter if you hit a farm in the middle of Kansas, or the Pacific halfway between the mainland and Hawaii... The end result would be, tragically, the same.

The safety aspect of daily ops isn't one size fits all; it's to scale. There are government minimums that have to be met, be it a 773 or a 738. Sure, the numbers (fuel pounds, etc) may differ, but that safety margin is custom tailored, if you will, for each aircraft and the associated variables on a flight-by-flight basis.

If you really don't like flying on twins, then you can easily forget visiting 3/4 of the world. Alternately, you can take a 17 day cruise from LA to HI. I'd like to echo the few posts that question how someone so scared of twins can be a member of this community. A majority of aircraft in service today in the commercial sector, at least in the US are twin engine aircraft. If that's a fact that scares someone away from air travel then good luck flying anyone other than QF, AF, Emirates, LH and a handful of others.

But I will say this, at 6'6" and 240 pounds - I do agree that widebodies are the way to go for longer flights, at least as far as comfort goes. ;)




You’re missing an important point


If you have a decompression at any point
on your route from JFK to LAX there are numerous airports to choose from where you can land almost immediately


ETOPS planning demands that not only should you be able to lose an engine at any
point during the flight and be able to proceed to your ETOPS alternate but also,
in the event of a decompression that you can complete this diversion at 10,000 feet
significantly increasing your fuel burn


I’m sure the 737 can comply with these requirements, it must as it’s already flying to HNL, I know at my airline however they
do go out with empty seats sometimes as the payload must be restricted to meet fuel
burn requirements


So comparing a transcon flight to a west coast- HNL run is not realistic, the ETOPS
portion is far more restrictive and demanding


While bigger aircraft certainly won’t be ‘filling their tanks’ on a similar route they
do have the performance (and fuel tank capacity) to operate with no weight restrictions

Thank and I say Amen to that!
 
Aviano789
Topic Author
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:05 pm

ThePinnacleKid wrote:
rbavfan wrote:
ThePinnacleKid wrote:

I can comfortably answer an aspect of this part cubs... having flown the ERJ and now the 767... both can obviously bang an engine and comfortably fly on the one remaining engine... the ERJ though has a much lower SE cruising altitude than the 767... I imagine, that in this case... that may in fact be what the poster was implying as to preference to avoid 737/320 family on long ETOPS flights.... As for myself.. knowing how the 767 was designed specifically with extended overwater operations in mind, like other large twins... vs the 737 which is not.. I also would pick an old WB over the new 73's any day on the Hawaii run.... Hawaii is a true ETOPS 180 run... much more critical than flying the Atlantic for example. While a poster above is correct.. both are certified to have it all go bad at the worst spot, drop down, and keep trucking, I still would rather be on the one that was designed for the mission over the one that inherited the mission.

As to an actual operational numbers... yesterday in the 763 on a transcon run, our midpoint SE ability (nearing the rockies) had a drift down altitude of FL301 still.... we had just over 55k lbs payload and 40k fuel still on board at that point... I don't know how the 737 numbers actually stack up in a similar situation... but someone else here who has a type in that might be able to expand on that airframes capabilities.



The 767 was not designed specifically for ETOPS. It was designed for domestic use based on a United Airlines requirement. The ETOPS was created later after TWA started flights TATL flights to Europe. When started they had to fly a more northerly route and once engine performance meet better specs it was upgraded to allow 120 & then 180. First flights went over Canada, Greenland & Iceland to meet safety requirements at the time. This is well covered in old issues of Aviation Week & Air transport world and other magazines in the early to late 80's. TWA was the airline that pushed for it.



Never said it was specifically for ETOPS... I said it was specifically with extended overwater operations IN MIND.... which it was... It was designed in tandem with the 757 with the distinct characteristics to be fuel efficient with mid range and mid capacity runs... and it was first deployed on domestic and transcon runs because planes didn't start with ETOPS back then... the first variants didn't have the range to effectively do it on the "blue spruce runs" (efficiency wise)... but you are absolute on point with the development and who and when.... I can also say a lot here in this thread focus so so so much on the ETOPS being the engine thing... it's not. So much goes into an aircraft flying ETOPS runs and there is more than just engine reliability. I stand by the fact I would prefer a wide body or 757 vs a 737/A320 on the Hawaii run... look at the levels of redundancies of systems on a 767 vs a 737, A320, ERJ. All airliners are highly reliable and redundant.. some just go a step further. I never truly realized how over the top redundant some aircraft were until I got my 75/76 type rating. The plane is a beast and a joy to fly.

A true and honest professional Indeed!
 
ThePinnacleKid
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:11 pm

Cubsrule wrote:
What redundancies do the 75/76 have that, say, a 321NEO lacks?


I would have to talk to a 737 or A320 typed guy and compare... but I do know the ones I'm typed in... where it comes down to it is not that it has redundancy and another doesn't... its more the manner in which redundancies are handled.. depth levels of it.. like even on simple Braking in the 767 we have: Normal Brakes, Alternate Brakes, Reserve Brakes, and then finally down to the accumulator... Aircraft Trimming - we have Electric trim, alternative trim, and then a Pitch Enhancement System in case the loss of all hydraulics... or for instance how redundancies are backed up to a deeper level by using another system to aid the failed - such as in our electric system (beyond the backups contained within the system like batteries) we also have a Hydraulic Driven Generator which can then power 7 of our buses and provided everything needed to continue in ETOPS operations despite massive system failures.
"Sonny, did we land? or were we shot down?"
 
nine4nine
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:15 pm

stratclub wrote:
catiii wrote:
nine4nine wrote:

No, but given range issues due to fuel I wouldn’t feel comfortable being down an engine and flying lower altitude with higher fuel burn or even the added drag. I’d imagine any issue on a mainland-Hawaii flight to the likes of the WN issue would have resulted in a major tragedy.

I will never book a Hawaii flight personally on an 320/321 or 737. Have heard stories about planes arriving on fumes after stronger than expected headwinds. Couple that with an engine issue. I think it’s a disaster in the making.


"Fumes?" My gosh, this post takes the hyperbole on this site to a whole new level.

Enlighten us, where did you hear about these potential catastrophes?

Being that Jet A has a flash point of 100F degrees, where exactly do these alleged "fumes" come from? Most likely what should have been quoted was that the aircraft(s) in question dipped into their reserves.



Yes. I stand corrected. Fumes was more of an exaggerated analogy but dipping into reserves should have been said.
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Cubsrule
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:25 pm

ThePinnacleKid wrote:
Cubsrule wrote:
What redundancies do the 75/76 have that, say, a 321NEO lacks?


I would have to talk to a 737 or A320 typed guy and compare... but I do know the ones I'm typed in... where it comes down to it is not that it has redundancy and another doesn't... its more the manner in which redundancies are handled.. depth levels of it.. like even on simple Braking in the 767 we have: Normal Brakes, Alternate Brakes, Reserve Brakes, and then finally down to the accumulator... Aircraft Trimming - we have Electric trim, alternative trim, and then a Pitch Enhancement System in case the loss of all hydraulics... or for instance how redundancies are backed up to a deeper level by using another system to aid the failed - such as in our electric system (beyond the backups contained within the system like batteries) we also have a Hydraulic Driven Generator which can then power 7 of our buses and provided everything needed to continue in ETOPS operations despite massive system failures.


But the fact that the ERJ is less redundant than the 767 isn't relevant to this discussion unless Embraer suddenly decides to seek ETOPS certification for it . . .
I can't decide whether I miss the tulip or the bowling shoe more
 
BerenErchamion
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:31 pm

Aviano789 wrote:
BerenErchamion wrote:
dwachdorf wrote:
Would having 4 engines actually increase the risk of having something like a catastrophic fan blade / disk failure? Also, I’d much rather have a proven engine like the CFM56, than a Trent 1000 or PW engine that’s having issues on the A321neo.


Yes. Whether this is enough to offset the lower likelihood of every engine failing in a contained manner depends on the specific failure rates of the engines in question, but there is such a point where that becomes the case.

Consider the case where a given engine has an uncontained, catastrophic failure rate of one every twenty hours, and a contained, non-catastrophic failure rate of one every two hours. If you mount two of those engines on a plane, you would expect a catastrophic failure of a single engine once every ten hours, and a contained failure of all engines once every four hours. If you mount three, you'd expect a catastrophic failure of a single engine once every 6 2/3 hours, and a contained failure of all engines once every eight hours. With four, it's a single catastrophic failure expected every 5 hours, and a contained all-engine failure every 16 hours. With 5, it's single catastrophic every 4 hours, and contained all-engine every 32.

If we translate this to probability of failure per hour, then:
With two engines, the probability of an uncontained failure in a given hour is 0.1, and the probability of all engines experiencing a contained failure in a given hour is 0.25, or a 35% chance of a fatal failure of some sort per hour. With three, it's 0.15 for single uncontained, and 0.125 for all uncontained, so 27.5% chance. With four, it's 0.2 for single uncontained, and 0.0625 for all uncontained, so a 26.25% chance of a failure of any sort. Finally, with five engines, it's 0.25 for single catastrophic, and 0.03125 for all uncontained, so 28.125% chance of failure every hour--so five engines is actually less safe than four.

Obviously, this is a simplified example--as you add more engines, you're probably going to be using a different type which will have different failure rates, for one, and also not all uncontained engine failure scenarios are equally fatal, but the point is that there is a point where adding more engines makes the plane less safe.

The original post by me was intended for single isle twins like the B737 series aircraft flying from the west coast to Hawaii. It was not meant for the WB like 757, 767,A330 and 777 series designed specifically with extended overwater operations in mind. My Bad. Please accept my apology for the confusion.


There was no confusion. You original post was complete and utter nonsense and had already been roundly refuted; I was responding to a post addressing a tangential point.

Also, a 757 is most definitely not a widebody.
 
ThePinnacleKid
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:39 pm

Cubsrule wrote:
But the fact that the ERJ is less redundant than the 767 isn't relevant to this discussion unless Embraer suddenly decides to seek ETOPS certification for it . . .


Correct... but I speculate that in a lot of ways that design philosophy to the needs for redundancy level is different in a 737 vs a 757/767. Obviously the 737 earned the sign off... and it can do it... but it does get back to my stance; I would just prefer to be on the one that the mission was the intended vs the mission was the inherited. The comparison and why I say ERJ is simply because it's what I flew and can speak to and in some ways, the mission of the ERJ is actually very similar to the original mission of the 737 when the design first saw the light of day.
"Sonny, did we land? or were we shot down?"
 
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AirKevin
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:50 pm

MildBlueYonder wrote:
Back on topic, I feel that the chance of dying on board from a medical emergency due to pre-existing issues (e.g. heart attack or stroke) or acquired conditions (e.g., pulmonary embolism or pneumothorax if one is prone to such things) must be statistically higher than going down from engine failure. Which I guess begs the question, perhaps widebodies ARE safer because you're more likely to be riding with a health care professional? And the single-engine cruise speed might be higher so you can get to a hospital sooner?

I was once on a United flight, Boeing 737-800, from MCO to EWR. As we were passing PHL, a medical emergency occurred, and flight attendants asked for any doctors on board to go to the back of the plane. There were at least 4 people that got up and went to the back.
barney captain wrote:
I think it's a "gift" from Boeing for new aircraft - at least that's what we were told. I don't know if it's SOP, but we certainly didn't want that much fuel. The a/c was delivered form RNT to PAE, where it had wifi and a few other mods done, then we ferried it to GEG for paint. The irony of full tanks for a 38 min flight with only two pilots wasn't lost on us. The double irony is that (according to the pain shop at least) they have to defuel the a/c prior to paint.

I thought they would have had to check for fuel leaks, so I guess they would have had to fill the tanks all the way in order to do that. Then my understanding from having read posts here is that once a plane is de-fueled, the fuel can't go anywhere else other than back in the same plane or another plane belonging to the same company. Maybe this is why they filled the tanks prior to delivery? Then again, maybe not. I guess they'd have to do some flight testing after the plane gets painted. Interesting.
Captain Kevin
 
UPNYGuy
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 9:54 pm

JackMeahoff wrote:
IPFreely wrote:
george77300 wrote:
How do you plan on getting to Hawaii then. I assume 757/777 has the same twin issue for you.


He most likely believes 757/777 twins are not twins like 737's/320's are, or are somehow safer twins. It makes as much sense as thinking 737's/320's are "landing on fumes" but people can believe whatever they want. It falls in the category of superstition, not science.


I like the ocean liner analogy. Cruise ships don't cross oceans, ocean liners do. More heavily built, higher bow, fewer windows near the water line, etc. The 737 was designed to be a regional jet, not a long range transoceanic jet.

Funny how so many commentators on here seem to be praising the use of narrowbody regional jets to cross oceans. As if this is some milestone to be celebrated.

In reality 737s and A320s crossing oceans is a sad indicator of the sorry state of the aviation industry. Gone are the days of faster, higher, bigger, better.


Comparing an ocean liner to a cruise ship is VERY flawed logic. In fact, the ONLY ocean liner in service is Queen Mary. If you go to http://www.cruise.com and do a simple search for transatlantic crossings, you will find the vast majority of them are on cruise ships. Most cruise lines do a multitude of transatlantic cruises per year in order to reposition ships. I go on 4 to 5 cruises per year, so this statement holds no validity.
 
birdbrainz
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 10:32 pm

JackMeahoff wrote:

In reality 737s and A320s crossing oceans is a sad indicator of the sorry state of the aviation industry. Gone are the days of faster, higher, bigger, better.


Higher? A quick look at Flightaware.com reveals that a lot of the 737-800's are cruising at FL370 and FL380, with a few at FL410. Ditto for the MAX 8, and the 737-700s are, as a group, cruising a bit higher than the 800's. Other than possibly a Concorde or 747-SP, can you name another plane from the "good 'ole days" that routinely cruises higher than that?

As far as better goes, check the trip fuel burn per pound of payload of a Max 8 on a 6-7 hr journey and get back to me.

This is not your grandfather's 737. ;-)
A good landing is one you can walk away from. A great landing is if the aircraft can be flown again.
 
IPFreely
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 10:36 pm

birdbrainz wrote:
JackMeahoff wrote:

In reality 737s and A320s crossing oceans is a sad indicator of the sorry state of the aviation industry. Gone are the days of faster, higher, bigger, better.


Higher? A quick look at Flightaware.com reveals that a lot of the 737-800's are cruising at FL370 and FL380, with a few at FL410. Ditto for the MAX 8, and the 737-700s are, as a group, cruising a bit higher than the 800's. Other than possibly a Concorde or 747-SP, can you name another plane from the "good 'ole days" that routinely cruises higher than that?

As far as better goes, check the trip fuel burn per pound of payload of a Max 8 on a 6-7 hr journey and get back to me.

This is not your grandfather's 737. ;-)


I don't think he meant "faster, higher, bigger, better" literally. I think he is either whining or trolling. This is what happens with free membership.
 
Antarius
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 10:53 pm

ThePinnacleKid wrote:
Cubsrule wrote:
But the fact that the ERJ is less redundant than the 767 isn't relevant to this discussion unless Embraer suddenly decides to seek ETOPS certification for it . . .


Correct... but I speculate that in a lot of ways that design philosophy to the needs for redundancy level is different in a 737 vs a 757/767. Obviously the 737 earned the sign off... and it can do it... but it does get back to my stance; I would just prefer to be on the one that the mission was the intended vs the mission was the inherited. The comparison and why I say ERJ is simply because it's what I flew and can speak to and in some ways, the mission of the ERJ is actually very similar to the original mission of the 737 when the design first saw the light of day.


The issue is you cannot lump all generations of the 737 into one thing. The 732 had JT8Ds on them, for example. The current crop of 737s are very different than the originals and actually are designed for missions that they do today.
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johns624
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 11:30 pm

ThePinnacleKid wrote:
Cubsrule wrote:
What redundancies do the 75/76 have that, say, a 321NEO lacks?


I would have to talk to a 737 or A320 typed guy and compare... .
So you don't know, do you? Yet you stated it as fact.
 
CallmeJB
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 11:34 pm

johns624 wrote:
ThePinnacleKid wrote:
Cubsrule wrote:
What redundancies do the 75/76 have that, say, a 321NEO lacks?


I would have to talk to a 737 or A320 typed guy and compare... .
So you don't know, do you? Yet you stated it as fact.

Well, he didn't know details but he inferred, as a professional.

He inferred that neither of those aircraft has a Hydraulic Motor Generator. He is right.

He didn't mention it, but neither of those aircraft have an Air Driven Pump (ADP) for hydraulics, either. This pump is powered by bleed air and powers the entire center system (flight controls, landing gear, alternate brakes, stab trim, nose wheel steering, and HMG).

So, in a 767 you can lose all electrics, and still power all three hydraulic systems (Left from left Engine Drive Pump (EDP), right from right EDP, and center from ADP), and power the HMG, which will provide electric power for standby instruments and what we call 'ETOPS instruments': Communication, Navigation, Captain's EFIS screens, and an EICAS screen. And the 767 *still* has a RAT as a backup for that. Even with the loss of all electrics, there are full hydraulics and partial electrics *with redundancy* for both systems.

Neither the 737 or A320 have backup systems that run that deep into other systems.

-Current 767 Captain

PS I would still feel perfectly safe flying west-coast to HI in a 737 or A320... it simply isn't that long of a flight
 
Max Q
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Mon Apr 30, 2018 11:56 pm

I believe the 737 will keep the APU running for these ETOPS flights providing some electrical redundancy


I distinctly remember passing underneath a 737 going to HNL that
was producing 3 contrails

We spoke to the crew and they confirmed the APU was running for that reason
The best contribution to safety is a competent Pilot.


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CallmeJB
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 12:04 am

Max Q wrote:
I believe the 737 will keep the APU running for these ETOPS flights providing some electrical redundancy

Like I said, that airframe is fine for the relatively short leg west coast to HNL.

But there is still no backup after those three generators go.

Electrics:
767: 2 engine generators, 1 APU generator, and a hydraulic generator: 4 gens
737: 2 engine generators, 1 APU generator: 3 gens

Hydraulics:
767: 2 engine pumps, 4 electric pumps, 1 air driven pump, 1 RAT: 8 hydraulic pumps (partially because there is no manual reversion for flight controls)
737: 2 engine pumps, 2 electric pumps: 4 hydraulic pumps (and manual reversion available)


Look, again, the 737 is a fine airframe. I'm just saying, don't jump down PinnacleKid's throat when he says the 767 has more redundancies. It clearly does.
 
Tucker1
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 12:09 am

ikolkyo wrote:
nine4nine wrote:
767333ER wrote:
What you have to ask yourself is how long this type of engine has been in service and how much use in total such as hours have been put on it. Just because one operator has had some trouble for whatever reason doesn’t mean the engine is suddenly unsafe if everyone else’s is fine still.


No, but given range issues due to fuel I wouldn’t feel comfortable being down an engine and flying lower altitude with higher fuel burn or even the added drag. I’d imagine any issue on a mainland-Hawaii flight to the likes of the WN issue would have resulted in a major tragedy.

I will never book a Hawaii flight personally on an 320/321 or 737. Have heard stories about planes arriving on fumes after stronger than expected headwinds. Couple that with an engine issue. I think it’s a disaster in the making.


Those are some made up stories since it would be illegal for a plane to land below reserves on a regular flight.


Why would it be illegal to land if you are on reserves? Doesn't make sense. You have to get down safely before you are empty and get down in a bad way
 
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XAM2175
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 12:19 am

Tucker1 wrote:
Why would it be illegal to land if you are on reserves? ...


It's not illegal to land while using reserve fuel. It is, however, illegal to dispatch a flight with the deliberate intention of using reserve fuel as part of the fuel load you expect to require for the normal trip.
 
Cubsrule
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 12:20 am

CallmeJB wrote:
Max Q wrote:
I believe the 737 will keep the APU running for these ETOPS flights providing some electrical redundancy

Like I said, that airframe is fine for the relatively short leg west coast to HNL.

But there is still no backup after those three generators go.

Electrics:
767: 2 engine generators, 1 APU generator, and a hydraulic generator: 4 gens
737: 2 engine generators, 1 APU generator: 3 gens

Hydraulics:
767: 2 engine pumps, 4 electric pumps, 1 air driven pump, 1 RAT: 8 hydraulic pumps (partially because there is no manual reversion for flight controls)
737: 2 engine pumps, 2 electric pumps: 4 hydraulic pumps (and manual reversion available)


Look, again, the 737 is a fine airframe. I'm just saying, don't jump down PinnacleKid's throat when he says the 767 has more redundancies. It clearly does.


OK, but is more redundancies demonstrably safer? It seems to me that one could argue that manual reversion is better than a few more pumps.
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7BOEING7
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 12:50 am

AirKevin wrote:
MildBlueYonder wrote:
Back on topic, I feel that the chance of dying on board from a medical emergency due to pre-existing issues (e.g. heart attack or stroke) or acquired conditions (e.g., pulmonary embolism or pneumothorax if one is prone to such things) must be statistically higher than going down from engine failure. Which I guess begs the question, perhaps widebodies ARE safer because you're more likely to be riding with a health care professional? And the single-engine cruise speed might be higher so you can get to a hospital sooner?

I was once on a United flight, Boeing 737-800, from MCO to EWR. As we were passing PHL, a medical emergency occurred, and flight attendants asked for any doctors on board to go to the back of the plane. There were at least 4 people that got up and went to the back.
barney captain wrote:
I think it's a "gift" from Boeing for new aircraft - at least that's what we were told. I don't know if it's SOP, but we certainly didn't want that much fuel. The a/c was delivered form RNT to PAE, where it had wifi and a few other mods done, then we ferried it to GEG for paint. The irony of full tanks for a 38 min flight with only two pilots wasn't lost on us. The double irony is that (according to the pain shop at least) they have to defuel the a/c prior to paint.

I thought they would have had to check for fuel leaks, so I guess they would have had to fill the tanks all the way in order to do that. Then my understanding from having read posts here is that once a plane is de-fueled, the fuel can't go anywhere else other than back in the same plane or another plane belonging to the same company. Maybe this is why they filled the tanks prior to delivery? Then again, maybe not. I guess they'd have to do some flight testing after the plane gets painted. Interesting.


Fuel leaks are checked for on the ground before it ever flies.

BC had a full tank of fuel because airlines that forego customer flights are given up too a full load of fuel, depending on the specifics of their contract.
 
barney captain
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 1:39 am

BC had a full tank of fuel because airlines that forego customer flights are given up too a full load of fuel, depending on the specifics of their contract.


Great info - thanks!
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JackMeahoff
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 2:30 am

IPFreely wrote:
birdbrainz wrote:
JackMeahoff wrote:

In reality 737s and A320s crossing oceans is a sad indicator of the sorry state of the aviation industry. Gone are the days of faster, higher, bigger, better.


Higher? A quick look at Flightaware.com reveals that a lot of the 737-800's are cruising at FL370 and FL380, with a few at FL410. Ditto for the MAX 8, and the 737-700s are, as a group, cruising a bit higher than the 800's. Other than possibly a Concorde or 747-SP, can you name another plane from the "good 'ole days" that routinely cruises higher than that?

As far as better goes, check the trip fuel burn per pound of payload of a Max 8 on a 6-7 hr journey and get back to me.

This is not your grandfather's 737. ;-)


I don't think he meant "faster, higher, bigger, better" literally. I think he is either whining or trolling. This is what happens with free membership.


I just traveled ORD-LGA-ORD on an AA 737-800 and we cruised at 25,000 feet both ways. Anyways...

Faster, bigger, better.

Those you can't take away.
 
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hOMSaR
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 2:39 am

JackMeahoff wrote:
I just traveled ORD-LGA-ORD on an AA 737-800 and we cruised at 25,000 feet both ways. Anyways...




Your point being?
The plural of Airbus is Airbuses. Airbii is not a word.
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32andBelow
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 2:56 am

JackMeahoff wrote:
IPFreely wrote:
birdbrainz wrote:

Higher? A quick look at Flightaware.com reveals that a lot of the 737-800's are cruising at FL370 and FL380, with a few at FL410. Ditto for the MAX 8, and the 737-700s are, as a group, cruising a bit higher than the 800's. Other than possibly a Concorde or 747-SP, can you name another plane from the "good 'ole days" that routinely cruises higher than that?

As far as better goes, check the trip fuel burn per pound of payload of a Max 8 on a 6-7 hr journey and get back to me.

This is not your grandfather's 737. ;-)


I don't think he meant "faster, higher, bigger, better" literally. I think he is either whining or trolling. This is what happens with free membership.


I just traveled ORD-LGA-ORD on an AA 737-800 and we cruised at 25,000 feet both ways. Anyways...

Faster, bigger, better.

Those you can't take away.

Yah it’s a short flight. I just felt on a 737 at FL410. Anyways the only bigger plane that is really faster is the 747. And 757s are small and fast
 
ThePinnacleKid
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 3:33 am

CallmeJB wrote:
Look, again, the 737 is a fine airframe. I'm just saying, don't jump down PinnacleKid's throat when he says the 767 has more redundancies. It clearly does.


Thank you so much!

To the critics: I simply stated exactly my knowledge base and my inferences based upon those as a REAL LIFE professional actually doing the real job... this blasting stuff is EXACTLY why I took an over 5 year hiatus from want-a-be's on this sight... it doesn't matter to many here that you do what they wish they could and you speak from a place of professionalism to help expand upon your views of things... You get blasted for it.

Sorry dear arm chair experts... let me know when you've commanded anything you know so much about that clearly I'm incompetent about... I'll pass your reviews on to my chiefs and throw away my 7k+ hrs of flying airliners. I'm sorry; I specifically gave information to real statistics on data I know and can speak about to be honest and truthful and also provided insight to why I specifically feel the way I do and have reservations on things the way I do.

I NEVER said the 737 was not ETOPS or couldn't do the mission... I merely said that I GET where the OP was coming from and as a fact... levels of redundancy are different for different airframes despite being similarly certified... and for me; to go to Hawaii I would PREFER an aircraft other than the 737/A320... not because they aren't capable aircraft, reliable aircraft, or lack redundancy... but simply, there are other airframes I feel give a wider margin of error over a flight that is in fact, despite distance, more an ETOPS run than even the North Atlantic runs.... Hawaii is a true ETOPS 180 beast. It's not to be joked about.

This one foray back into trying to be a voice of the other side has just made me want to walk away yet again and lock the big metal door to you all.. I don't need it. I get the paycheck and do what I love... sorry for wanting to share my perspectives and feelings to others.
"Sonny, did we land? or were we shot down?"
 
ThePinnacleKid
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 3:52 am

Cubsrule wrote:
OK, but is more redundancies demonstrably safer? It seems to me that one could argue that manual reversion is better than a few more pumps.


Pretty much any pilot would always pick to have an extra redundancy over less... why would you not? more important is HOW the redundancy is accomplished... and most of these don't end up in a manual reversion state.. they just end. Good night. So long. System over.

By spreading the redundant layers over different systems means the loss of one.. a totally unrelated can then provide data/support/help to the failed system etc... again it's the ability for Electric to be provided via hydraulic systems.. trim via hydraulics instead of normal electric.. etc, etc, etc.... it's not that it's redundant or not... because they all are.. it's the depth of backup... Warm fuzzy level. I never said the 737/A320 couldn't do it or that it's dangerous... I just said the wide bodies and 757/767 do provide a better margin of safety thanks to deeper levels of redundancy. It's a simple physical design difference. I stand by my feelings and my choices. If I have a choice other than a 737/A320 series over the US-Hawaii run.. I'll take it. Safer is just safer.. but we're talking the safest of two super safe things...
Last edited by ThePinnacleKid on Tue May 01, 2018 4:01 am, edited 1 time in total.
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IPFreely
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 3:58 am

ThePinnacleKid wrote:
...Warm fuzzy level...I stand by my feelings and my choices.


Fortunately the people who design aircraft and the people who set certification standards and approve them understand and use science, engineering, and statistics. And they don't make decisions based on warmth, fuzziness, and feelings.
 
ThePinnacleKid
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 4:06 am

IPFreely wrote:
ThePinnacleKid wrote:
...Warm fuzzy level...I stand by my feelings and my choices.


Fortunately the people who design aircraft and the people who set certification standards and approve them understand and use science, engineering, and statistics. And they don't make decisions based on warmth, fuzziness, and feelings.


Yup, and so we can all enjoy the flight across the pacific on the 737. What's your point? Trying to discredit me for my stance? Doesn't work... my stance is my stance... I've flown over on 737's and I've flown to hawaii in the 757/767... I'll take my 767. It's just better suited.

I speak as a pilot that's actually 767 PIC type rated... I prefer my extra redundancy flying over extended oceanic operations. The OP asked. I responded. It's clear and factual.. ALL operating ETOPS are certified for ETOPS. The end. SOME ETOPS certified aircraft have more depth to redundancy than others.. it's a fact. THE END. I FOR MYSELF pick more flair than minimum flair... happy office space to us all and may everyone get to hawaii to have an umbrella drink
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DaveFly
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 4:17 am

I’ve flown eight times nonstop from NYC to Honolulu. All on HA 330s. I just happen to like HA. The 330 was just a fringe benefit — the widebody has a perceived spaciousness, despite the same crappy seats, than that of a 320/737. But they’re all designed for the same mission, with the same ETOPS requirements. I’m not sure I understand the fear/suspicion of flying a narrowbody over water. I’ve also flown the 757 from NYC - London. Perfectly fine.
717,727,737,747,757,767,777,787
L1011,DC8,DC9,DC10,MD80/90
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CRJ,E135/45/190,
DH8,Avro85,DHBeaver,AstarHelo,F100,ATR42
 
ThePinnacleKid
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 4:33 am

DaveFly wrote:
I’ve flown eight times nonstop from NYC to Honolulu. All on HA 330s. I just happen to like HA. The 330 was just a fringe benefit — the widebody has a perceived spaciousness, despite the same crappy seats, than that of a 320/737. But they’re all designed for the same mission, with the same ETOPS requirements. I’m not sure I understand the fear/suspicion of flying a narrowbody over water. I’ve also flown the 757 from NYC - London. Perfectly fine.


They're actually not designed for the same mission despite being able to serve safely the same mission.

In the 737NG for instance because of the lack of redundancy depth vs the 767... they were required to continuously run the APU all the way for an extra generator...

did it matter to anyone peering out the window ordering a coke? NO.
Did it make the flight less safe? NO.
Did it mean the 737 couldn't do the flight? NO.
Does the 737 have less redundancy should things start going south than the 767? YES.

It's not a fear things.. it's just a "what it is, is what it is"...

Same as my old beloved ERJ at MGTOW had a MUCH lower SE drift down ability vs the 767... planes are different and with different intentions... the 737 is a capable safe aircraft with amazing statistics.... so is the 767... and more than all those my precious ex ERJ is the statistical safest... but which of them is BEST suited for Mainland US to Hawaii? ERJ / 737 / 767? easy.. 767. It just was engineered with a different redundancy depth built in than the other two... less is not more in this case... and pure statistically NONE of it matters... statistically if you picked the ERJ; you're the safest hour for hour.

(just in your example to be clear.. the 757, despite narrow body, has roughly the same depth of system redundancy as the 767.. it's evidently, exactly as I suspected, more than the 737 and A320 which were conceived for originally different missions)
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FlyHappy
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 5:30 am

ThePinnacleKid wrote:

This one foray back into trying to be a voice of the other side has just made me want to walk away yet again and lock the big metal door to you all.. I don't need it. I get the paycheck and do what I love... sorry for wanting to share my perspectives and feelings to others.



Heya - just wanted to chime in and say as the self-anointed "voice of the silent majority" - we appreciate you pilots, ATC's, aerospace engineers and others from the industry to take your time here to share your knowledge. We really do. Don't let a few flame-throwing knuckleheads get under your skin.

See, you've taught me via this thread something I wasn't cognizant of or would have easily guessed - that in fact, there are fewer redundancies in some aircraft over others despite being certified for the same missions. In fact, had you not been flamed, likely the other pilot (I think a pilot) would not have come to your defense, spelling out some specifics of the 767 vs 737 redundancies (which than you later expanded on). I had the same vague thought about why you initially stated the difference existed, without citing an example. But, of course, I give the benefit of the doubt on these forums when the writer sounds otherwise knowledgeable (as you do). But still - its very rewarding for me to see more detail to illustrate what you spoke of (generators, RAT, and such).

So in some small way - maybe the flamer served a net positive purpose ?
Whatever you take from this, know that interested lay persons like myself enjoy the contributions of industry pros like yourself, so thank you.

PS - All my TPAC/HI flying has been on WB, or the ol' DC-8, 707 NB's.......... I imagine my next HI trip could well be on new gen NB, and though I will not have any trepidation, damned if I won't be thinking about the lack of a RAT !!!
 
FlyHappy
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 5:46 am

IPFreely wrote:
ThePinnacleKid wrote:
...Warm fuzzy level...I stand by my feelings and my choices.


Fortunately the people who design aircraft and the people who set certification standards and approve them understand and use science, engineering, and statistics. And they don't make decisions based on warmth, fuzziness, and feelings.


sure, but they are also not in the cockpit, at the controls, with responsibility for hundreds of pax, if/when a serious emergency occurs.
so it seems quite understandable to me that for the 1 or 2 people who have minutes, or hours at the very most, to see a crisis to a safe conclusion to prefer to have the *maximum* failsafes and redundancies at hand.

All the standards or statistics in the world will not make a 4th redundancy appear when you've lost your only 3. This is what our pilot is telling us, and he/she has no need to "scientifically justify" the probabilty of a triple-loss; its just a personal preference for more gear and design. I get it, it's pretty darn simple, and completely relatable.
 
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 6:28 am

ThePinnacleKid wrote:

To the critics: I simply stated exactly my knowledge base and my inferences based upon those as a REAL LIFE professional actually doing the real job... this blasting stuff is EXACTLY why I took an over 5 year hiatus from want-a-be's on this sight... it doesn't matter to many here that you do what they wish they could and you speak from a place of professionalism to help expand upon your views of things... You get blasted for it.


I'll echo what Flyhappy and a few others have said. We've lost a lot of good professional insight here lately. And it is true that no matter what your experience says, there will be the normal retinue of jackasses to tell you you're all wet. In a word, fuck em. There are still plenty of pros and enthusiasts here who read up to get a good vibe of what the industry is doing, and to see better detail of why things are the way they are.

I'm actually on my way out of this business, but still enjoy hearing about the various complexities of things I don't work with day to day. And when we chase pros away, that gets less so. So thanks for chiming in, and keep it up as able.
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Cubsrule
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 11:39 am

ThePinnacleKid wrote:
Cubsrule wrote:
OK, but is more redundancies demonstrably safer? It seems to me that one could argue that manual reversion is better than a few more pumps.


Pretty much any pilot would always pick to have an extra redundancy over less... why would you not? more important is HOW the redundancy is accomplished... and most of these don't end up in a manual reversion state.. they just end. Good night. So long. System over.

By spreading the redundant layers over different systems means the loss of one.. a totally unrelated can then provide data/support/help to the failed system etc... again it's the ability for Electric to be provided via hydraulic systems.. trim via hydraulics instead of normal electric.. etc, etc, etc.... it's not that it's redundant or not... because they all are.. it's the depth of backup... Warm fuzzy level. I never said the 737/A320 couldn't do it or that it's dangerous... I just said the wide bodies and 757/767 do provide a better margin of safety thanks to deeper levels of redundancy. It's a simple physical design difference. I stand by my feelings and my choices. If I have a choice other than a 737/A320 series over the US-Hawaii run.. I'll take it. Safer is just safer.. but we're talking the safest of two super safe things...


It sounds like we are saying the same thing: it’s a trickier question than merely counting the number of redundancies. Look at fly by wire, for instance. Without manual reversion the aircraft need more redundancies. Does that necessarily mean that a 320 is safer than a 738? No; the systems are merely designed differently.

Saying that more redundancies are better than fewer is a perfectly fine normative choice, but let’s be honest with one another that merely counting redundancies is just as superficial as preferring the 320 over the 738 because the cabin is wider.
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lightsaber
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 12:51 pm

Why are we debating ETOPS? ETOPS has been a fact my entire career and I'm closer to retirement than starting work.

Cubsrule wrote:
ThePinnacleKid wrote:
Cubsrule wrote:
OK, but is more redundancies demonstrably safer? It seems to me that one could argue that manual reversion is better than a few more pumps.


Pretty much any pilot would always pick to have an extra redundancy over less... why would you not? more important is HOW the redundancy is accomplished... and most of these don't end up in a manual reversion state.. they just end. Good night. So long. System over.

By spreading the redundant layers over different systems means the loss of one.. a totally unrelated can then provide data/support/help to the failed system etc... again it's the ability for Electric to be provided via hydraulic systems.. trim via hydraulics instead of normal electric.. etc, etc, etc.... it's not that it's redundant or not... because they all are.. it's the depth of backup... Warm fuzzy level. I never said the 737/A320 couldn't do it or that it's dangerous... I just said the wide bodies and 757/767 do provide a better margin of safety thanks to deeper levels of redundancy. It's a simple physical design difference. I stand by my feelings and my choices. If I have a choice other than a 737/A320 series over the US-Hawaii run.. I'll take it. Safer is just safer.. but we're talking the safest of two super safe things...


It sounds like we are saying the same thing: it’s a trickier question than merely counting the number of redundancies. Look at fly by wire, for instance. Without manual reversion the aircraft need more redundancies. Does that necessarily mean that a 320 is safer than a 738? No; the systems are merely designed differently.

Saying that more redundancies are better than fewer is a perfectly fine normative choice, but let’s be honest with one another that merely counting redundancies is just as superficial as preferring the 320 over the 738 because the cabin is wider.

100% agree counting redundancies isn't the full picture. At some point the weak link is an actuator or other single item.

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cledaybuck
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Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 1:02 pm

lightsaber wrote:
Why are we debating ETOPS? ETOPS has been a fact my entire career and I'm closer to retirement than starting work.

Cubsrule wrote:
ThePinnacleKid wrote:

Pretty much any pilot would always pick to have an extra redundancy over less... why would you not? more important is HOW the redundancy is accomplished... and most of these don't end up in a manual reversion state.. they just end. Good night. So long. System over.

By spreading the redundant layers over different systems means the loss of one.. a totally unrelated can then provide data/support/help to the failed system etc... again it's the ability for Electric to be provided via hydraulic systems.. trim via hydraulics instead of normal electric.. etc, etc, etc.... it's not that it's redundant or not... because they all are.. it's the depth of backup... Warm fuzzy level. I never said the 737/A320 couldn't do it or that it's dangerous... I just said the wide bodies and 757/767 do provide a better margin of safety thanks to deeper levels of redundancy. It's a simple physical design difference. I stand by my feelings and my choices. If I have a choice other than a 737/A320 series over the US-Hawaii run.. I'll take it. Safer is just safer.. but we're talking the safest of two super safe things...


It sounds like we are saying the same thing: it’s a trickier question than merely counting the number of redundancies. Look at fly by wire, for instance. Without manual reversion the aircraft need more redundancies. Does that necessarily mean that a 320 is safer than a 738? No; the systems are merely designed differently.

Saying that more redundancies are better than fewer is a perfectly fine normative choice, but let’s be honest with one another that merely counting redundancies is just as superficial as preferring the 320 over the 738 because the cabin is wider.

100% agree counting redundancies isn't the full picture. At some point the weak link is an actuator or other single item.

Lightssaber
Despite all the talk in here about the plane, engines, and ETOPS, I think history and statistics will show that the weak link in the whole system is still the pilot (no offense intended to pilots, they generally do a great job).
As we celebrate mediocrity, all the boys upstairs want to see, how much you'll pay for what you used to get for free.
 
sixtyseven
Posts: 807
Joined: Thu Nov 16, 2006 9:42 am

Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 2:14 pm

Aviano789 wrote:
Just recently a Boeing 737-800 operator from Seattle (SEA) to Honolulu (HNL) with 165 people on board had to drift down to FL230 and continued to HNL for a safe landing about 2:45 hours after leaving FL350, due to an oil filter bypass indication for one of its CFM56 engines. It is a fact most twin isles operators have conducted 1000s of such flights over open water safely without a hitch. Taken into account the recent events with WN 1380 and the reported growing issues with that engine version, would the manufactures re-consider three or four engines airframe designs in the future to increases more safety margin for this type of operation? And would a three or four engine design end the need for ETOPS ops certification for twins?


Well yes. A 3 or 4 engine design would end the need for ETOPS certification. Do you know what ETOPS stands for??
Stand-by for new ATIS message......
 
BerenErchamion
Posts: 208
Joined: Thu May 28, 2015 12:44 am

Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 2:27 pm

sixtyseven wrote:
Aviano789 wrote:
Just recently a Boeing 737-800 operator from Seattle (SEA) to Honolulu (HNL) with 165 people on board had to drift down to FL230 and continued to HNL for a safe landing about 2:45 hours after leaving FL350, due to an oil filter bypass indication for one of its CFM56 engines. It is a fact most twin isles operators have conducted 1000s of such flights over open water safely without a hitch. Taken into account the recent events with WN 1380 and the reported growing issues with that engine version, would the manufactures re-consider three or four engines airframe designs in the future to increases more safety margin for this type of operation? And would a three or four engine design end the need for ETOPS ops certification for twins?


Well yes. A 3 or 4 engine design would end the need for ETOPS certification.


Not anymore.
 
CallmeJB
Posts: 70
Joined: Fri Oct 13, 2017 9:19 pm

Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 2:57 pm

Cubsrule wrote:
It sounds like we are saying the same thing: it’s a trickier question than merely counting the number of redundancies. Look at fly by wire, for instance. Without manual reversion the aircraft need more redundancies.

When it comes to the Hydraulic systems, yes. The additional redundancies to account for the lack of manual reversion is an engineering debate. One may not be better than the other.

When it comes to the electrical system, there is no doubt: the 767 has more backups than the 737.

But, again, the 2000 mile leg simply is not that long! The 737 and A320 are both, now, adequate at handling those legs from the west coast. It's not a walk in the park, but it's within the design capabilities.

At my airline, a west coast to HI leg IS a walk in the park. A more typical route would be East Coast USA to Western Europe, where the 2000 mile overwater leg is only half the journey; that's the bread and butter of what wide body aircraft do.

The longest leg I've operated in the 767 was a ferry flight from TLV straight to MEM... 15+ hours in flight. The 1500 mile oceanic portion was a relatively small part of that total flight. We didn't coast out in Shanwick until we were past the halfway point in the flight, and when we coasted in over Canada there was still four hours of flying left. If we had lost a generator or a hydraulic pump over the Middle East or Europe, we could have continued across the North Atlantic ETOPS 180 or downgraded to ETOPS 120 depending on the exact failure. Compare that to the 737, where any failure in an ETOPS critical system after takeoff will prevent them from crossing the pond.

As has been noted in this thread before, the 767 was not designed with ETOPS in mind... ETOPS didn't exist when the 767 was designed. But the 767 was designed for long, international legs. Can a 737 fly from Europe to South Africa? Maybe, at the limits of its range, it could do it. Can it handle system failures along the way, and continue? No, most component failures will mean that you are landing short of your destination. The 767 was designed to be capable of handling component failures and continuing to the destination. This is a design requirement when operating to far flung destinations over third-world regions.

The 737 is capable of the relatively easy West Coast USA to Hawaii USA ETOPS route. Is it one of the longest ETOPS overwater legs out there? Yes it is. But you see, that simplifies things: any component failure means a diversion to one end or the other. Either way you are in a populous and advanced country.

The less-easy decisions occur over part of the Middle East, Central Asia, and Africa. Do you divert to Libya, Chad, or continue to your destination of Lagos? Sure, you have the performance to fly single-engine all the way to Lagos, but how do you justify overflying N'Djamena? You can't, you must land. And with choices like that, I'd rather have no choice at all... that's why the Hawaii leg is easy.

-Current 767 Captain (repeated only because somebody questioned it upthread)
 
ImperialEagle
Posts: 2372
Joined: Sat Jan 14, 2006 10:53 am

Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 3:33 pm

Aviano789 wrote:
There has never been an ETOPS-caused fatality in the history of aviation. Ever.

SAll of which have killed pax on TPACs.... than you are of an ETOPS issue, which never has.

Ponder that.

A few Sundays ago CBS 60 Minutes reported on a low cost air carrier know in the industry for its maintenance deficiencies. The reporting was supported by the FAA Obscure Mechanical Interruption Summary. The report highlighted more than 100 serious in flight mechanical incident that carrier had from January 2016 to October 2017.
My question to you: Knowing the foregoing information about this airline, would you feel comfortable buying a ticket for your self and love ones to fly over 2000 miles of open water on any of their twins?
[i]By the way although ETOPS did not exist at time Flying Tiger Flight 923, which occurred in the dark of night during a raging storm in the cold North Atlantic Ocean. Seventy six persons were aboard. Twenty eight passengers and crew (including a mother and her two children) perished, while an unbelievable 48 survived the crash and three-day storm.
[/i][/quote]

Falling Tiger's Flight 923?? Strange analogy. That was a Super H that had four of the most unreliable (piston) engines ever hung on an airframe, Wright 3350T/C's.

Ridiculous comparison. AND in the age of the old windmills, ditching was a common occurance. Not so these days.
"If everything seems under control, you're just not going fast enough!"
 
Cubsrule
Posts: 13841
Joined: Sat May 15, 2004 12:13 pm

Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 3:41 pm

CallmeJB wrote:
The longest leg I've operated in the 767 was a ferry flight from TLV straight to MEM... 15+ hours in flight. The 1500 mile oceanic portion was a relatively small part of that total flight. We didn't coast out in Shanwick until we were past the halfway point in the flight, and when we coasted in over Canada there was still four hours of flying left. If we had lost a generator or a hydraulic pump over the Middle East or Europe, we could have continued across the North Atlantic ETOPS 180 or downgraded to ETOPS 120 depending on the exact failure. Compare that to the 737, where any failure in an ETOPS critical system after takeoff will prevent them from crossing the pond.


You raise many good points, but I want to drill down on this one. Is an aircraft that has enough redundancies that it can essentially fail to a 737 level of redundancy and continue (assuming no further failures) safer than a 737 that would need to land in the first instance? If we are talking about systems where failures beget failures, perhaps the 767, though it has more options, is not much or not at all safer.
I can't decide whether I miss the tulip or the bowling shoe more
 
mcg
Posts: 963
Joined: Tue Sep 16, 2003 11:49 am

Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 3:41 pm

JackMeahoff wrote:
rbavfan wrote:


The early models of the 737 were designed for shorter flights. However as they have evolved, like us humans did. What they could accomplish has increased with technology. Otherwise we would be waiting a week of more for your response to this. After all we did not have telephones or computer networks 500 years ago, but we had people traveling for days to send a message.



And yet for some reason the safety requirements for flying the President of the United States didn't evolve. Four engines then, four engines now. The Air Force must know something the bean counters at the airlines and their lackeys at the FAA don't. Trump can afford to lose two engines on Air Force One but I can only afford to lose one on my 737 before I go in the drink.


Actually the President routinely flies on a 757. President Obama flew the 757 to Hawaii. I know President Bush senior turned up in Aspen on a Gulfstream.
 
catiii
Posts: 3058
Joined: Mon Mar 31, 2008 1:18 am

Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 5:42 pm

nine4nine wrote:
stratclub wrote:
catiii wrote:

"Fumes?" My gosh, this post takes the hyperbole on this site to a whole new level.

Enlighten us, where did you hear about these potential catastrophes?

Being that Jet A has a flash point of 100F degrees, where exactly do these alleged "fumes" come from? Most likely what should have been quoted was that the aircraft(s) in question dipped into their reserves.



Yes. I stand corrected. Fumes was more of an exaggerated analogy but dipping into reserves should have been said.


Now that we know you are prone to exaggeration, share these instances. They went into their hold fuel? Divert fuel? What reserves?
 
ThePinnacleKid
Posts: 530
Joined: Wed Feb 23, 2005 9:47 am

Re: Flying 2000 miles over open water in twins powered by CFM56-7

Tue May 01, 2018 7:00 pm

CallmeJB wrote:
The longest leg I've operated in the 767 was a ferry flight from TLV straight to MEM... 15+ hours in flight. The 1500 mile oceanic portion was a relatively small part of that total flight. We didn't coast out in Shanwick until we were past the halfway point in the flight, and when we coasted in over Canada there was still four hours of flying left. If we had lost a generator or a hydraulic pump over the Middle East or Europe, we could have continued across the North Atlantic ETOPS 180 or downgraded to ETOPS 120 depending on the exact failure. Compare that to the 737, where any failure in an ETOPS critical system after takeoff will prevent them from crossing the pond.

As has been noted in this thread before, the 767 was not designed with ETOPS in mind... ETOPS didn't exist when the 767 was designed. But the 767 was designed for long, international legs. Can a 737 fly from Europe to South Africa? Maybe, at the limits of its range, it could do it. Can it handle system failures along the way, and continue? No, most component failures will mean that you are landing short of your destination. The 767 was designed to be capable of handling component failures and continuing to the destination. This is a design requirement when operating to far flung destinations over third-world regions.


Excellent points. My longest leg on the 767 has been HNL to DRW... 11 1/2 hr repositioning flight.... all oceanic and ETOPS with 2 ETP's... def. was an area I appreciate the level of redundancies with the 767; eyebrow raising when the second portion of the ETOPS segments cover large areas with speculated continued human cannibalism. That's also when you know how real it all is when our crew briefing even included that during that second segment; should we be forced down and into a ditching, it would be as far from islands as possible specifically for that reason and for our FA's to prep supplies as necessary if that became a need.
"Sonny, did we land? or were we shot down?"

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