Print from Airliners.net discussion forum
http://www.airliners.net/aviation-forums/general_aviation/read.main/5588740/

Topic: Qatar Airways 787 Gets Coloured Engines
Username: 777way
Posted 2012-10-16 07:55:15 and read 18380 times.

Glad they deviated from the recommended norm which sheeple airlines are following, however the grey was also an option initially, but then again why didnt ANA opt for that, hope QR inspires them and others to change as well.


View Large View Medium
Click here for bigger photo!

Photo © Royal S King

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: Stitch
Posted 2012-10-16 08:48:49 and read 18040 times.

With NH's color scheme trending mostly white, white nacelles strike me as a better choice than grey.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: 777way
Posted 2012-10-16 09:03:43 and read 17926 times.

Actually you have a point, maybe they should update their fleet look by painting all engines to match the 787.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: 777way
Posted 2012-10-16 09:16:55 and read 17796 times.

ANA have grey engines on their other types A320, 737, 747, 777.

Qatar demo aircraft at Farnborough had white engines on 787 inline with Boeings recommendation that white is best suited to cut drag or whatever over 787 engines surfices.

Every airline seems to be following that blindly so far, QR are the only exception now besides airlines whose over all livery is white or belly is white and the engines colour wont affect their look such as JAL, Korean Air, Iraqi Airways, Thai, Qantas, Saudia, KLM amongst others.

[Edited 2012-10-16 09:22:20]

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: pnwtraveler
Posted 2012-10-16 09:21:15 and read 17754 times.

I thought in another thread about BA and the colour of their engines on the 787, it was said by someone that the only two colours on the nacelle could be white or grey. Something about other colours like blue needing to be thicker so that they interrupted the laminar flow.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: tdscanuck
Posted 2012-10-16 09:25:00 and read 17695 times.

Quoting 777way (Thread starter):
the grey was also an option initially, but then again why didnt ANA opt for that

No idea.

Quoting steex (Reply 3):
This isn't a 787-specific issue, the airlines could get the engines in any color they wanted on the 787

They can't get any colour they want, and this is specific to the 787.

Quoting 777way (Reply 4):
Qatar demo aircraft at Farnborough had white engines on 787 inline with Boeings recommendation that white is best suited to cut drag or whatever over 787 engines surfices.

White or grey. The Qatar 787 at Farnborough, I think, probably had non-final nacelles.

Tom.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: 777way
Posted 2012-10-16 09:25:44 and read 17695 times.

but all 787s are getting white engines including those of operators whos livery has grey engines like ANA, China Southern, Air China and Air New Zealand, though the latter two have yet to appear at painefield.

[Edited 2012-10-16 09:27:11]

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: steex
Posted 2012-10-16 09:28:38 and read 17650 times.

Quoting 777way (Reply 4):
ANA have grey engines on their other types A320, 737, 747, 777.

My apologies - I don't see NH often my way, and I've always thought their engines were white when I see them. Upon closer inspection, I can see the engines are grey in photos, though I could swear I'd seen other NH longhaul birds with white engines. In my defense, at many angles under bright lighting conditions, the difference between the light grey and white is very difficult to notice!

Quoting pnwtraveler (Reply 5):

I thought in another thread about BA and the colour of their engines on the 787, it was said by someone that the only two colours on the nacelle could be white or grey. Something about other colours like blue needing to be thicker so that they interrupted the laminar flow.

If that's the case, I move to strike my entire previous post from the record due to its uselessness!

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: by738
Posted 2012-10-16 11:18:12 and read 17125 times.

Quoting 777way (Reply 7):
all 787s are getting white engines including those of operators whos livery has grey engines

Well not all. QR.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: fruitbat
Posted 2012-10-16 13:31:39 and read 15452 times.

Quoting 777way (Reply 3):
Quoting 777way (Reply 6):

It's a really simple equation:

Lower drag = lower fuel burn = lower costs

If Boeing are saying that white or grey nacelles save a few tens or hundreds of dollars per flight due to laminar flow over the nacelle then that's the colour the airlines will paint them. It's difficult enough to make money as an airline without deliberately making things more difficult for yourself and not taking advantage of the latest technology to minimise operating costs - otherwise these airlines would have bought a 767 or A330!!

If the aethetics then work, it's a bonus. And I bet BA's 787 nacelles will be white.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: HOMsAR
Posted 2012-10-16 14:23:31 and read 14405 times.

Is there something special about the 787's necelles that make white/grey the only acceptable colors?

Is the efficiency/fuel burn penalty for painting the engines other colors any different for the 787 than for, say, any other airplane ever built?

If yes, how so? If not, then why the big deal about the 787's engines and not other types (some of which have more, or larger, engines)?

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: KELPkid
Posted 2012-10-16 14:28:06 and read 14294 times.

Quoting fruitbat (Reply 9):

It's a really simple equation:

Lower drag = lower fuel burn = lower costs

If Boeing are saying that white or grey nacelles save a few tens or hundreds of dollars per flight due to laminar flow over the nacelle then that's the colour the airlines will paint them. It's difficult enough to make money as an airline without deliberately making things more difficult for yourself and not taking advantage of the latest technology to minimise operating costs - otherwise these airlines would have bought a 767 or A330!!

If the aethetics then work, it's a bonus. And I bet BA's 787 nacelles will be white.

1) IIRC, the laminar flow/paint issue techincally only applies to the first 1/3 or so of the nacelle's length, so an airline could do something like only paint the first 1/3 or the nacelle white (or grey!)
2) It has to do with paint thickness. There is nothing that says the leading paint manufacturers couldn't design a new paint for the nacelles that didn't have to be applied as thick to allow colors on the nacelles...
3) I'll bet QR is just using the Boeing approved grey on their nacelles   

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: nitepilot79
Posted 2012-10-16 14:31:01 and read 14253 times.

Quoting Stitch (Reply 1):
With NH's color scheme trending mostly white, white nacelles strike me as a better choice than grey

Beautiful. The engine paint would really pop with an opposite-colored scheme of the vertical stabilzer graphic.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: Stitch
Posted 2012-10-16 14:42:31 and read 14032 times.

Quoting HOMsAR (Reply 10):
Is there something special about the 787's necelles that make white/grey the only acceptable colors?

Yes. It is required to maintain laminar flow farther down the nacelle.



Quoting HOMsAR (Reply 10):
Is the efficiency/fuel burn penalty for painting the engines other colors any different for the 787 than for, say, any other airplane ever built?

Yes. Doing so breaks the laminar flow, which increases fuel burn.

Quoting HOMsAR (Reply 10):
If yes, how so?

By using these two colors, Boeing in 2006 stated an airline could save 30,000 USG / 115,000 litres of fuel per year thanks to the extended laminar flow.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: clickhappy
Posted 2012-10-16 16:34:10 and read 12555 times.

Wow, that is a really nice photo     

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: davidho1985
Posted 2012-10-16 18:54:46 and read 11068 times.

sound crazy.

You spend multi-million dollars to buy a plane and you can not choose the colour you want freely on one of the most advanced plane in the world.....because it will affect the fuel efficiency lor

:P

[Edited 2012-10-16 18:57:44]

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: tdscanuck
Posted 2012-10-16 19:12:55 and read 10812 times.

Quoting davidho1985 (Reply 15):
sound crazy.

You spend multi-million dollars to buy a plane and you can not choose the colour you want freely on one of the most advanced plane in the world...

You spend multi-hundred-million dollars to buy a plane explicitly because it is very fuel efficient...that means you need to deal with all the features that were built in to make it very fuel efficient.

Tom.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: jbguller
Posted 2012-10-16 22:59:10 and read 8794 times.

Quoting tdscanuck (Reply 16):
You spend multi-hundred-million dollars to buy a plane explicitly because it is very fuel efficient...that means you need to deal with all the features that were built in to make it very fuel efficient.

Exactly. You don't buy a hybrid car to put a V8 engine in it. You buy a hybrid car because you want to help the environment, save money in the long run due to the efficiency of the vehicle, or because you're a celebrity with stacks of fuel-guzzling cars and you want to broaden your fan base.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: BMI727
Posted 2012-10-16 23:09:41 and read 8659 times.

Quoting Stitch (Reply 1):
With NH's color scheme trending mostly white, white nacelles strike me as a better choice than grey.

The white does look better.

Quoting Stitch (Reply 13):
By using these two colors, Boeing in 2006 stated an airline could save 30,000 USG / 115,000 litres of fuel per year thanks to the extended laminar flow.

...which is definitely enough to put looks firmly on the back burner.

Quoting jbguller (Reply 17):
You don't buy a hybrid car to put a V8 engine in it.

Of course not. That's just silly. You should buy a hybrid that comes with a V8 already in it.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: horstroad
Posted 2012-10-16 23:33:58 and read 8423 times.

Quoting Stitch (Reply 13):
By using these two colors, Boeing in 2006 stated an airline could save 30,000 USG / 115,000 litres of fuel per year thanks to the extended laminar flow.

with what fleet size? or is it per aircraft?

I can not believe that a) manufacturers can work that precise that a slightly thicker layer of paint would increase the fuel burn by 115000l (we are talking about 110th or 10th of a millimeter of paint. I bet the gaps between the cowlings, the rivets, dirt etc have more impact on the laminar flow) and b) that this only applies to the nacelles, and not to the fuselage, vertical stab etc...

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: tonymctigue
Posted 2012-10-17 00:39:37 and read 7835 times.

Quoting horstroad (Reply 19):
I can not believe that a) manufacturers can work that precise that a slightly thicker layer of paint would increase the fuel burn by 115000l (we are talking about 110th or 10th of a millimeter of paint. I bet the gaps between the cowlings, the rivets, dirt etc have more impact on the laminar flow) and b) that this only applies to the nacelles, and not to the fuselage, vertical stab etc...

Wow! Who would have thought? Does this also apply to the B748 seeing as my understanding is that the nacelle design and engines are pretty much idectical on both aircraft? Also, does this mean Boeing have had to develop a special system for applying the paint to the nacelles to ensure that the correct paint thickness is applied? Or are they painted before being attached to the aircraft? Sorry for all the question, but if the thickness of the paint makes that much difference then surely a guy with a bog standard spray gun just wouldn't cut it.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: 3rdGen
Posted 2012-10-17 02:04:18 and read 7086 times.

Most of the posters here point out that the white and gray paint reduce weight and increase laminar flow. My question is why? What is so special about this paint that it does this, and why does it have to be white or gray? What's the science behind it? Is it only because white and grey don't require a primer coat? If this is the case then the weight savings makes sense, but what about the laminar flow, why does only one coat of paint effect the laminar flow by so much? And what of the thousands of engines currently flying with different colours, what makes the 787 engines so special that white and grey has such an advantage with laminar flow and weight?

[Edited 2012-10-17 02:07:34]

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: tdscanuck
Posted 2012-10-17 06:31:39 and read 4744 times.

Quoting horstroad (Reply 19):
Quoting Stitch (Reply 13):
By using these two colors, Boeing in 2006 stated an airline could save 30,000 USG / 115,000 litres of fuel per year thanks to the extended laminar flow.

with what fleet size? or is it per aircraft?

Per aircraft.

Quoting horstroad (Reply 19):
I can not believe that a) manufacturers can work that precise that a slightly thicker layer of paint would increase the fuel burn by 115000l (we are talking about 110th or 10th of a millimeter of paint. I bet the gaps between the cowlings, the rivets, dirt etc have more impact on the laminar flow)

Laminar flow trip is pretty binary...the exact thickness you actually get isn't so important as making sure that whatever you get doesn't trip the boundary layer to turbulent. And yes, the OEM's can work out that precisely what the drag change is for laminar vs. turbulent flow over the forward nacelle.

Quoting horstroad (Reply 19):
b) that this only applies to the nacelles, and not to the fuselage, vertical stab etc...

The fuselage and vertical stab weren't built to have natural laminar flow so it's not (currently) a concern for them. The OEM's know there are gains to be had here...that's why Boeing has been testing hybrid laminar flow on the 787 empennage:
http://www.flightglobal.com/news/art...nar-flow-control-for-787-9-358123/

Quoting tonymctigue (Reply 20):
Wow! Who would have thought? Does this also apply to the B748 seeing as my understanding is that the nacelle design and engines are pretty much idectical on both aircraft?

Just visually, the 747-8 nacelle doesn't seem to be a natural laminar flow nacelle. The engines and nacelles are not identical between the aircraft (the 747-8 has a smaller fan).

Quoting tonymctigue (Reply 20):
Also, does this mean Boeing have had to develop a special system for applying the paint to the nacelles to ensure that the correct paint thickness is applied? Or are they painted before being attached to the aircraft?

They're base painted (i.e. white or grey) prior to installation. In the paint hanger they would apply customer-specific markings like placards.

Quoting tonymctigue (Reply 20):
if the thickness of the paint makes that much difference then surely a guy with a bog standard spray gun just wouldn't cut it.

That's why they don't use a guy with a bog standard spray gun to paint it.

Quoting 3rdGen (Reply 21):
Most of the posters here point out that the white and gray paint reduce weight and increase laminar flow. My question is why? What is so special about this paint that it does this, and why does it have to be white or gray?

Nothing is magic about white and grey, the "magic" is very tightly controlling the surface. Apparently, Boeing choose the two most common and simple to keep as many people happy as possible.

Quoting 3rdGen (Reply 21):
And what of the thousands of engines currently flying with different colours, what makes the 787 engines so special that white and grey has such an advantage with laminar flow and weight?

The 787 is the only large aircraft, currently, with natural laminar flow nacelles. The magic is very tight control of the mold line (i.e. the aerodynamic shape). If you don't have that built in, which all other current airliners don't, then it doesn't matter what colour you paint them.

Tom.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: imiakhtar
Posted 2012-10-17 06:44:56 and read 4579 times.

Whilst we're on the topic of laminar flow, I recently got to speak with a Piaggio 180 test pilot. According to him, if the paintwork is damaged or faded, the P180 will lose around 6kts from cruising speed. (costs around $80 000 to put a new coat on P180).

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: 3rdGen
Posted 2012-10-17 08:35:56 and read 3677 times.

Quoting tdscanuck (Reply 22):

The 787 is the only large aircraft, currently, with natural laminar flow nacelles. The magic is very tight control of the mold line (i.e. the aerodynamic shape). If you don't have that built in, which all other current airliners don't, then it doesn't matter what colour you paint them.

OK so if I get you right Boeing has developed the right paint to do this job and so far they're only offering white and grey/

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: tdscanuck
Posted 2012-10-17 08:41:15 and read 3706 times.

Quoting 3rdGen (Reply 24):
OK so if I get you right Boeing has developed the right paint to do this job and so far they're only offering white and grey/

I doubt they developed the paint to do the job...I suspect they picked the paint first then matched the design to the paint. But yes, as the moment, you get white or grey.

Tom.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: BMI727
Posted 2012-10-17 10:20:37 and read 3497 times.

Quoting imiakhtar (Reply 23):

Whilst we're on the topic of laminar flow, I recently got to speak with a Piaggio 180 test pilot. According to him, if the paintwork is damaged or faded, the P180 will lose around 6kts from cruising speed.

Sounds about right, but it probably makes a great deal of difference where the damage is. The Avanti is designed to have a large amount of laminar flow, I want to say it's something like 1/3 of the aircraft.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: 777way
Posted 2012-10-17 10:41:50 and read 3454 times.

Quoting by738 (Reply 8):

Wow Brainac! did you bother see who started the topic and its content before replying?

Quoting tdscanuck (Reply 25):

But grey has not been chosen by three airlines whose regular livery feature grey engines, ANA, China Southern and United, the question is why did they not opt for the matching colour if the option wa available?

Its not like any of the three have plans to paint their other aircraft types engines white, even if we leave NH out since 787 is teh only thing happening for them now, CZ have not applied white engines to A380 or ERJs nor are UA repainting their fleet into the merged UA/CO livery with white engines.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: KELPkid
Posted 2012-10-17 12:41:30 and read 3280 times.

Quoting BMI727 (Reply 26):
Sounds about right, but it probably makes a great deal of difference where the damage is. The Avanti is designed to have a large amount of laminar flow, I want to say it's something like 1/3 of the aircraft.

Someone at the local GA field has one, and it is incredibly loud on flyover (which doesn't bother me!   ). It sounds like an airborne Ferrari, somehow, although I know it has a pair of PT-6's and not two flat plane V8's   But to my ears, it sounds just like a V8 Ferrari...

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: BMI727
Posted 2012-10-17 12:44:16 and read 3263 times.

Quoting KELPkid (Reply 28):
Someone at the local GA field has one, and it is incredibly loud on flyover (which doesn't bother me!   ).

The Avanti has a unique (and to some, irritating) sound because of its pusher design and the way the exhausts are arranged. Inside, it's supposedly very quiet compared to similar aircraft.

Topic: RE: Qatar Airways 787 Gets Coloured Engines
Username: bikerthai
Posted 2012-10-18 06:02:53 and read 2839 times.

Quoting tdscanuck (Reply 22):

Quoting tonymctigue (Reply 20):
if the thickness of the paint makes that much difference then surely a guy with a bog standard spray gun just wouldn't cut it.

That's why they don't use a guy with a bog standard spray gun to paint it.

Maybe it not the overall thickness of the paint that makes the difference. Perhaps it's the consistency of the thickness over the area that you apply the paint. If you add additives to give color, you may not get a uniform surface at the micro level as the paint particle may cause an uneven surface when view under a microscope. Just conjecture . . .

bt


The messages in this discussion express the views of the author of the message, not necessarily the views of Airliners.net or any entity associated with Airliners.net.

Copyright © Lundgren Aerospace. All rights reserved.
http://www.airliners.net/