Mason From United States, joined Jun 1999, 719 posts, RR: 0 Posted (8 years 8 months 1 day 15 hours ago) and read 700 times:
The other day, I was pondering why (with the exception of the 747-400) Boeing has chosen not to have winglets on its longer-range aircraft. Airbus has always integrated a winglet into its wings (except for a few early A320s), even on short-range aircraft where winglets do not provide significant fuel conservation. Why on aircraft such as the 777 and 767ERs did Boeing choose to omit the winglet? Will the 777X series have winglets?
Jet Setter From , joined Dec 1969, posts, RR: Reply 3, posted (8 years 8 months 1 day 14 hours ago) and read 608 times:
The 767-400 and 777X series have raked wing tips, patented by Boeing, they are more efficient than winglets. There is information and pictures of the raked wing tips at boeing.com in the 767-400 section. Ordinary 757/767/777s have very efficient wings and were all original designs, a winglet is a sign you are trying to improve on a less-than-optimal design (like when Airbus made the A300 into the A300-600R "long-haul" variant with the same wing etc) The 737NG has a totally new wing, and winglets are only neccessary if you really want to strech the range. I expect the A340 has winglets to get as much range as possible, no idea why the A320/330 have them. The A3XX won't have winglets. If you design your wings well enough - you shouldn't need them
Cedarjet From United Kingdom, joined May 1999, 7029 posts, RR: 44 Reply 5, posted (8 years 8 months 1 day 14 hours ago) and read 584 times:
Saying the A340 needs winglets to squeeze extra performance is mean and also wrong - as Ben88 says, it's the best wing in the business. Fact. And what's this about the A300-600R? It hardly has winglets, just little fences to stop clumsy mechanics falling off the ends of the wings (hoho). If you want to talk about winglets being added to old wing designs, Jet Setter, have you heard of the 747-400?
The first commerical aircraft with winglets were Learjets, and they have great, highly efficient wing designs that were ahead of their time. It has nothing to do with fixing an inefficient design, it's making the whole wing work and depends upon many factors.
Yes! Senator Obama. We are ready to believe again.
Sammyk From United States, joined Oct 1999, 1672 posts, RR: 0 Reply 6, posted (8 years 8 months 1 day 14 hours ago) and read 568 times:
Actually, the A340/330 wing is not as efficient as it could be had it been built for ONE specific plane, but its a compromise for both the 340 and 330.
The 777 wing is actually considered the best around, mainly because it was designed for one airframe from the start, and for only one engine, and growth was designed into it so that future models would not suffer from an inefficient wing.
Also, I hear the A3XX will have wingtip fences like those found on the A310 and A320.
ZRH From Switzerland, joined Nov 1999, 4723 posts, RR: 24 Reply 7, posted (8 years 8 months 1 day 12 hours ago) and read 553 times:
I don't think that the wing of the A 330/340 is a compromise between two aircrafts because they have exactly the same fuselage (e.g. the -300's), they only have different numbers of engins.
Delta772 From United States, joined Oct 2006, 0 posts, RR: 0 Reply 8, posted (8 years 8 months 1 day 9 hours ago) and read 526 times:
Actually, I have read that the A330/A340 wing IS a compromise. I think they were originally designed for entirely different missions, the 330 for a short/medium haul airBUS type operation, and the A340 for long haul. That's why they put the 4-engines on the A340. So the wing is a compromise between the differing needs of the two distinct missions.
Hamlet69 From United States, joined Mar 2000, 2241 posts, RR: 52 Reply 9, posted (8 years 8 months 1 day 8 hours ago) and read 513 times:
From what I have heard (mostly from AI people) the A330/A340 wing is a definite compromise between the two market types, medium and long-haul. The reason it has winglets, however, is not because of this. The A340 program was originally intended to have the IAE SuperFan engine. This engine was way ahead of its time, and IAE/Airbus decided that the commercial risks were too great. i.e. there was no way they could have developed it and certified it in the time the airlines wanted the aircraft. When the CFM56 was chosen as a replacement, the wing that they had been using was not enough to meet promised design goals. So they lengthened it and replaced the intended 'wing fences' with full-blown winglets. This revision is exactly what Boeing did with the 744.
Saying AI wanted to squeeze extra performance is not wrong at all. Both Airbus and Boeing are always looking for ways to gain an edge over each other. This is one aerodynamic trick that helps.
Boeing727 From United States, joined May 1999, 822 posts, RR: 0 Reply 10, posted (8 years 8 months 1 day 8 hours ago) and read 507 times:
It is true that a well designed wing usually does not need winglets for the aircraft's mission (e.g. short/medium haul flights). The winglet on the A330/340s wing was designed more in mind for the A340 and its extremely long range, where winglets have an advantage on fuel consumption. We see the same design on the B744; although the B744D has none, because the aircraft's mission does not benefit from that additional weight. The idea has been brought up to retrofit B747 classics that would be used for long distance flying with winglets, but that still needs to be seen.
We can see that almost no short/medium haul aircraft with well aerodynamically designed wings, even the A320 family I don't count, have no real winglets. All these aircrafts' wings are so well designed that the addition of winglets and their additional weight would not make it a more efficient aircraft.
Hamlet69 From United States, joined Mar 2000, 2241 posts, RR: 52 Reply 11, posted (8 years 8 months 14 hours ago) and read 451 times:
I just wanted to add that the compromise between the A330 (short/medium) and the A340 (long) is one of the reasons the A330-200 is such a great aircraft. It has a wing perfectly suited to its niche in the market place (between medium and long haul routes).
Rocket Roger From , joined Dec 1969, posts, RR: Reply 13, posted (8 years 7 months 2 weeks 6 days 8 hours ago) and read 407 times:
Winglets are more than just to improve handling! They increase lift! They extend the wing to what the legnth of what it would be if they stuck out straight. The Learjet-60 has winglets, which I work on, and they are like having a whole lot more wing, The only reason the Lear didnt have longer wings, is to decrease hangar space needed, and to make crosswind landings easier. By the way, The 727 was the best wing design.... EVER!
Airbus_A340 From Hong Kong SAR, PRC, joined Mar 2000, 1497 posts, RR: 13 Reply 14, posted (8 years 7 months 2 weeks 6 days 1 hour ago) and read 389 times:
To: Jet Setter
the A3XX will have winglets.Go here...:
http://airbus.com/images/a3xx-side-bg.jpg
to some of you guys you say that the A320 hardly have winglets?! they are small ones, what are you people on about they dont do much of a difeence, etc, etc...
Airbus wouldnt have just "stuck" them on for no reason. The A3XX will have similar winglets as to those on the A32X versions. see for your self on the link.
hope it has helped
trev*
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