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- dl767captain
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Why No Winglets On The A380
Is there a reason that there are no winglets on the A380 (instead of those little triangle things)? Not like the 737 ones, they would probably be huge, but something like the 747-400 has. Did it just not save enough to matter?
RE: Why No Winglets On The A380
I believe it needs to fit in an 80m box at the airport. The A380 wingspan is over 79m, so winglets would take it over the 80m mark.
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- LHRBlueSkies
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RE: Why No Winglets On The A380
The wings have fences, not winglets, as the advanced wing design doesn't need the extra stablising effect provided by winglets. I think!
flying is the safest form of transport - until humans get involved!
RE: Why No Winglets On The A380
Adding winglets to the WhaleJet would put the wingspan over 80 meters and then there would be zero airports with suitable gates.
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- TomFoolery
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RE: Why No Winglets On The A380
After Aviation Partners finishes figuring out how to add blended winglets to everything on the Boeing family, I am sure they will move to Airbus 
(Its a joke)
(ha)
Ton
(Its a joke)
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Ton
Paper makes an airplane fly
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- SimProgrammer
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RE: Why No Winglets On The A380
It was also a winglet vs. wingfence decision based on weight vs. drag reduction abilility
Drive a bus, an Airbus, easier than a London bus!
RE: Why No Winglets On The A380
| Quoting LHRBlueSkies (Reply 2): The wings have fences, not winglets, as the advanced wing design doesn't need the extra stablising effect provided by winglets. I think! |
The purpose of winglets is not to provide a 'stabilizing effect'...it's to reduce drag.
2H4
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RE: Why No Winglets On The A380
| Quoting DL767captain (Thread starter): Is there a reason that there are no winglets on the A380 (instead of those little triangle things)? |
They're not so little...
7late7, A3latey, Sukhoi Superlate... what's going on?
RE: Why No Winglets On The A380
| Quoting DL767captain (Thread starter): Is there a reason that there are no winglets on the A380 |
Found on the net:
"Basically winglets help to reduce induced drag and improve performance (also increases aspect ratio slightly). However, the Airbus A380 has very large wing area due to the large wingspan that gives it a high aspect ratio. So, it need not have to worry about aspect ratio but needs only to tackle the induced drag problem. Therefore, it does not require the winglets, but merely "wingtip fences" similar to those of the Airbus A320."
Hope it helps.
RE: Why No Winglets On The A380
| Quoting Breiz (Reply 8): Therefore, it does not require the winglets, but merely "wingtip fences" similar to those of the Airbus A320." |
No aircraft requires winglets, but every wing (with the possible exception of delta wings) can benefit from them. Additionally, a properly-designed blended winglet will reduce drag more effectively than a "wingtip fence".
2H4
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RE: Why No Winglets On The A380
The additional weight must outweight the drag reduction benefits. Like with the 772ER.
RE: Why No Winglets On The A380
| Quoting DL767captain (Thread starter): Is there a reason that there are no winglets on the A380 (instead of those little triangle things)? Not like the 737 ones, they would probably be huge, but something like the 747-400 has. Did it just not save enough to matter? |
It doesn't need them. A winglet only makes sense when you are span-restricted. A raked wingtip or a straight-out span increase is always more weight-efficient than a winglet.
| Quoting Breiz (Reply 8): However, the Airbus A380 has very large wing area due to the large wingspan that gives it a high aspect ratio. |
Something's not right about this...large wing area with a large wingspan gives you a lower aspect ratio, not a higher one.
Tom.
RE: Why No Winglets On The A380
| Quoting 2H4 (Reply 12): Quoting Tdscanuck (Reply 11): It doesn't need them. Well, technically, no aircraft needs winglets....the aircraft will simply be less efficient without them. |
Touche. To put it a little more properly...the potential performance gain for winglets on the A380 doesn't justify the cost and weight increase winglets would impose.
Tom.
RE: Why No Winglets On The A380
| Quoting EGNR (Reply 7): They're not so little... |
And, not realised by many, they're made by Boeing!
| Quoting RJ111 (Reply 10): The additional weight must outweight the drag reduction benefits. |
Then why would they have fitted them?
| Quoting Tdscanuck (Reply 11): A winglet only makes sense when you are span-restricted. |
Then why do the A350 and 787 both have wing-tip devices on clean-sheet designs?
Maybe it's just to make the planes look cool. Time flies like an arrow. Fruit flies like a banana!
There are 10 types of people in the World - those that understand binary and those that don't.
There are 10 types of people in the World - those that understand binary and those that don't.
RE: Why No Winglets On The A380
| Quoting Art (Reply 1): I believe it needs to fit in an 80m box at the airport. The A380 wingspan is over 79m, so winglets would take it over the 80m mark. |
| Quoting Zvezda (Reply 3): Adding winglets to the WhaleJet would put the wingspan over 80 meters and then there would be zero airports with suitable gates. |
So if the wingspan is currently over 79m and, it needs to fit in an 80m box, its already looking a bit tight with almost no room for error, isnt it? This especially when we hear recently of several wing clippings in wide open airport spaces!!!
There isnt really a dark side to the moon, as a matter of fact its all dark!
RE: Why No Winglets On The A380
Looking at the pics in reply 7 made me wonder. What effect do large fences have when sideslipping? Wouldn't they cut a lot of wingtip lift? Perhaps you don't sideslip large commercial aircraft, making my question irrelevant.
RE: Why No Winglets On The A380
| Quoting Bill142 (Reply 17): Hawker de Havilland to be specific |
Yes, that nice Australian company with an incredible heritage. But, wholly-owned by Boeing.
Time flies like an arrow. Fruit flies like a banana!
There are 10 types of people in the World - those that understand binary and those that don't.
There are 10 types of people in the World - those that understand binary and those that don't.
RE: Why No Winglets On The A380
| Quoting 2H4 (Reply 6): The purpose of winglets is not to provide a 'stabilizing effect'...it's to reduce drag. 2H4 |
Adding winglets will reduce INDUCED drag to be specific.....
Downside: its adds PARASITE drag and weight to the airplane
That will be my only contribute to the "winglet" discussion.
I think its up to the manufacturers and operators to decide whether or not equip an a/c with winglets.
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- 3MilesToWRO
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- bristolflyer
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RE: Why No Winglets On The A380
| Quoting NEMA (Reply 16): So if the wingspan is currently over 79m and, it needs to fit in an 80m box, its already looking a bit tight with almost no room for error, isnt it? |
I'm sure the 'room for error' has been already built-in to the 80m figure. If the airports say that the aircraft can be no wider than 80m then the aircraft can be up to 80m safely.
Fortune favours the brave
RE: Why No Winglets On The A380
| Quoting 3MilesToWRO (Reply 21): Quoting Art (Reply 18): Perhaps you don't sideslip large commercial aircraft, making my question irrelevant. If you're gliding without fuel you do |
I've been in exactly that situation a few times. Come to think of it, I don't ever recall gliding any other way.
RE: Why No Winglets On The A380
| Quoting Tdscanuck (Reply 13): To put it a little more properly...the potential performance gain for winglets on the A380 doesn't justify the cost and weight increase winglets would impose. |
Perfectly worded!
| Quoting Art (Reply 18): Looking at the pics in reply 7 made me wonder. What effect do large fences have when sideslipping? Wouldn't they cut a lot of wingtip lift? |
By the time the relative wind starts to become blocked by winglets, you've got far larger problems to deal with.
| Quoting Ph-tvh (Reply 20): Adding winglets will reduce INDUCED drag to be specific..... Downside: its adds PARASITE drag and weight to the airplane |
Nevertheless, the net effect (of properly designed winglets) is a decrease in overall drag and an increase in efficiency.
2H4
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- hotelbravo
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RE: Why No Winglets On The A380
| Quoting BristolFlyer (Reply 22): 'm sure the 'room for error' has been already built-in to the 80m figure. If the airports say that the aircraft can be no wider than 80m then the aircraft can be up to 80m safely. |
There may not be room for error, but the fact is the only thing that would collide with an A380 with, say, 81 m wingspan in a neighboring gate is another A380. So the solution would be simply not to park two A380s side by side. So I'mnot sure I buy the 80 m box argument. I would rather go with the following:
| Quoting Tdscanuck (Reply 13): the potential performance gain for winglets on the A380 doesn't justify the cost and weight increase winglets would impose. |
Remember that the wing had to be reinforced during testing and extra weight added as it was.
RE: Why No Winglets On The A380
| Quoting 2H4 (Reply 24): Quoting Ph-tvh (Reply 20): Adding winglets will reduce INDUCED drag to be specific..... Downside: its adds PARASITE drag and weight to the airplane Nevertheless, the net effect (of properly designed winglets) is a decrease in overall drag and an increase in efficiency. |
Indeed if designed correctly it should overcome the weight/parasite drag issues and be more efficient.
This is different however for each specific kind of operation.
No environment crap, just cold heart math...
If the cost or inconvenience of winglets are higher than the little extra fuel consumption, forget it.
RE: Why No Winglets On The A380
| Quoting Art (Reply 1): A380 wingspan is over 79m, so winglets would take it over the 80m mark. |
| Quoting Zvezda (Reply 3): Adding winglets to the WhaleJet would put the wingspan over 80 meters |
Well, maybe it's just me, but I think you're looking at this 80m wingspan the wrong way round. The wingspan is 80m because it does NOT have winglets. I'm not a genius, but I assume that if winglets were designed for the A380, then the overall wingspan, including winglets, would still be 80m or less. Doesn't a winglet increase the effective aspect ratio anyway? So, an existing 80m wingspan would be similar to a 79m wingspan with 1m winglets ... in theory actually resulting in a shorter wingspan with the same aspect ratio.
Jimbo
I'd rather be on the ground wishing I was in the air, than in the air wishing I was on the ground!
RE: Why No Winglets On The A380
| Quoting Bond007 (Reply 27): I'm not a genius, but I assume that if winglets were designed for the A380, then the overall wingspan, including winglets, would still be 80m or less. |
I'm no genius, either, but I would guess that such an approach would involve much more work than simply adding structural reinforcements and bolting on some winglets. You seem to be talking about a wing shortening.
The mere mention of such an undertaking has probably sent a chill through the spines of many engineers over in Toulouse.
2H4
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RE: Why No Winglets On The A380
| Quoting 2H4 (Reply 28): I'm no genius, either, but I would guess that such an approach would involve much more work than simply adding structural reinforcements and bolting on some winglets. You seem to be talking about a wing shortening. The mere mention of such an undertaking has probably sent a chill through the spines of many engineers over in Toulouse. |
Well, my point is that had the engineers designed winglets for the A380, it would most probably still be 80m or less. The fact that the wingspan without winglets is 80m, IMO has little to do with why it doesn't have any.
Jimbo
I'd rather be on the ground wishing I was in the air, than in the air wishing I was on the ground!
RE: Why No Winglets On The A380
| Quoting Bond007 (Reply 29): Well, my point is that had the engineers designed winglets for the A380, it would most probably still be 80m or less. The fact that the wingspan without winglets is 80m, IMO has little to do with why it doesn't have any. |
Ah, I understand what you're saying. Perhaps it has something to do with the fact that they expect to use the same wing on future lengthened versions. This requirement might have prevented them from fully optimizing the wing for the current version.
2H4
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- Starlionblue
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RE: Why No Winglets On The A380
| Quoting Art (Reply 18): What effect do large fences have when sideslipping? Wouldn't they cut a lot of wingtip lift? Perhaps you don't sideslip large commercial aircraft, making my question irrelevant. |
It's all about proportions. Those fences are large but so are the wings. The effect is no different from the fences on a 319. As for sideslipping airliners, read up on the Gimli Glider.
| Quoting Bond007 (Reply 27): The wingspan is 80m because it does NOT have winglets. I'm not a genius, but I assume that if winglets were designed for the A380, then the overall wingspan, including winglets, would still be 80m or less. |
Indeed.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
RE: Why No Winglets On The A380
| Quoting Tdscanuck (Reply 11): Something's not right about this...large wing area with a large wingspan gives you a lower aspect ratio, not a higher one. |
The wording is confusing.
If you achieve a greater wing area through an increased span, then you will increase the aspect ratio. However, if you achieve a greater wing area through an increased chord, then you'll lower the aspect ratio.
The wingspan is squared in the equation for aspect ratio...ensuring that if wingspan and wing area both grow, you'll likely still get a greater aspect ratio.
I'm watching Jeopardy. The category is worst Madonna songs. "This one from 1987 is terrible".
RE: Why No Winglets On The A380
| Quoting 2H4 (Reply 28): The mere mention of such an undertaking has probably sent a chill through the spines of many engineers over in Toulouse. |
FWIW, the wing engineers would ideally have liked the A380's wing-span to be 83m, with a lower chord/higher aspect ratio. This requirement is driven by the task of making the wing aerodynamically efficient for the application up to 650 tonnes MTOW.
They were artificially constrained to 80m.
Don't know if that influenced the wing fence decision or not.
Regards
RE: Why No Winglets On The A380
| Quoting Scbriml (Reply 14): Quoting Tdscanuck (Reply 11): A winglet only makes sense when you are span-restricted. Then why do the A350 and 787 both have wing-tip devices on clean-sheet designs? scratchchin Maybe it's just to make the planes look cool. wink |
Because they're not span restricted. I specifically said *winglet*. A raked wingtip will always have better performance if you're got the margin to support it (which a cleansheet always will) and span (which the 787-8/9 and A350 do). You would always install a raked wingtip if you could (and you're asking an engineering...marketing might say something else).
Tom.
RE: Why No Winglets On The A380
| Quoting 2H4 (Reply 35): Quoting Tdscanuck (Reply 34): A raked wingtip will always have better performance Why? |
Because a raked wingtip increases span and generates lift. A winglet makes the wing fly like it has increased span but doesn't generate any lift. Both devices cause the rest of the wing to generate additional lift but only a device with horizontal extent generates any significant lift on its own.
Put another way, a winglet is just a raked wingtip bent up 90 degrees. You get most of the same change in airflow over the rest of the wing but you loose all the lift the wingtip was generating.
Tom.