Linked Questions

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Why don't more airplanes incorporate spiroid winglets? [duplicate]

In typical airplanes, lift induced drag can account for the majority of the overall drag. Why don't more aircraft employ methods to reduce this and specifically why not spiroid winglets? From every ...
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0answers
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Do winglets really improve efficiency and reduce drag? [duplicate]

Below are some pictures of various fixed wing aircraft with winglets. It is widely accepted that these winglets will improve an airplane's performance by reducing drag and therefore improving fuel ...
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Wings and winglets [duplicate]

Wouldn't a wider wing center section be a better solution than adding winglets? Say adding 5% to the span by increasing the size of the wing box and center section. Like they did when they built that ...
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6answers
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Would an 8% reduction in drag outweigh the weight addition from this custom CFD-tested winglet?

I'm writing an essay at school about why there is so much variation in winglet design. I am analysing all the primary types of winglets used today in the aviation industry. I'm constructing them in ...
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4answers
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Why is it rare for small aircraft to have winglets?

I've noticed that winglets are very rare on small aircraft. I wonder why this is the case. Wouldn't they have the same advantages, especially because they travel at low speed? Or is it just a wrong ...
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3answers
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How does an aircraft form wake turbulence?

This question discusses how wake turbulence can affect planes flying in formation. It got me wondering, how do aircraft (the wings in particular) form wake turbulence to begin with? It can't be as ...
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5answers
7k views

Would connecting propeller blades with a continuous ring reduce induced drag?

Turbine engines are covered, which of course is to contain the process (just like a super/turbocharged engine is as soon as the air enters the intake). But it got me thinking, doesn't this also reduce ...
32
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6answers
8k views

Why do propeller blades not have winglets?

On the first look this question might sound ridiculous and maybe it is. But as propeller blades act by the same physical laws as wings, and winglets reduce the induced drag by quite a bit, then why ...
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4answers
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How high does the ground effect last?

Up to which height is the ground effect still significant enough to be taken into account? Would this height be sufficient to actually fly above the ground, overcoming at least trivial obstacles like ...
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6answers
14k views

Do box-wings suffer from induced drag the same way as normal wings?

Most wings suffer from induced drag due to a pressure difference above and below the wing causing air to sneak around the tip, forming a vortex. There are various methods to minimize these effects, ...
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3answers
9k views

Why has the 777x been designed with folding wingtips?

I recently visited the Boeing factory outside Seattle, WA and noted in the distance a new 777x being built with, what looked like very large winglets. However, on closer inspection they're not - the ...
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5answers
4k views

Why is lift larger than thrust?

It's been a while since I tried to read a little about flight mechanics and aerodynamics, but I remember one question I had back then: Is the thrust of a common passenger aircraft (A320, B737) ...
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2answers
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Why does the Antonov AN-225 not have any winglets?

Winglets provide a lift boost that would be useful to a plane of this size. But the An-255 does not have any winglets. Why is it so?
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3answers
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Is wingtip design mature?

There are many wingtip design, all made to reduce vortex related drag, and neither boeing nor airbus seems to prefer one over another. They move from one design to another at each new aircraft, always ...
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4answers
4k views

Why don't horizontal stabilizers have winglets?

Winglets are used to reduce induced drag on the main wings of an aircraft as per explanations on wikipedia. Since they are very effective I was wondering why they are not installed also on horizontal ...
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3answers
5k views

Why is the use of tail-down force so common?

Why is the use of tail-down force so prevalent in aircraft design? Why not use canards to avoid induced drag?
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3answers
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How does the raked wingtip of the Boeing 787 work?

The wing tips are very different on these airplanes. The wingtip on a Boeing 787 is a sharp triangle, while the wingtip on a Boeing 737-300 is flat. British Airways Boeing 787-8 G-ZBJC wingtip | by ...
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2answers
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How does chord length affect wing design?

In comments on the answer to a question about transonic speeds and control surfaces I came across this comment and I'm having a hard time understanding it. If you increase the chord, lift goes up ...
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2answers
28k views

Why does the B777 have no winglets? Are there any drawbacks to having winglets?

I have googled and noticed that almost every Boeing 777 is not equipped with winglets. Does anybody know the reasons why Boeing did not equip B777s with winglets? Are there any drawbacks to having ...
13
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2answers
22k views

What is the method to calculate a finite wing's lift from its sectional airfoil shape?

I am struggling to get my head around a concept that I believe should be fairly simple to understand. Lift versus drag and AoA data of many airfoils are freely available, for instance the NACA 4-...
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4answers
2k views

Why don't airliners have rudders on the winglets?

There are a couple airplanes out there that use the winglet as the rudder, but why doesn't the winglet have a rudder on it to increase the turn of the aircraft?
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3answers
3k views

Why do airfoil's trailing edges point downward?

The trailing edge of and airfoil is mostly pointing downward. Is there any reason for that? Down wash increases drag and down wash is due to the direction of air pointing down. If the trailing edge is ...
6
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2answers
1k views

Why does wake turbulence sink?

There has been a remarkable story this week of a Challenger 604 business jet being rolled after encountering the wake turbulence of an A380. A Challenger 604 at FL340 operating from Male-Abu Dhabi ...
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2answers
2k views

Why do winglets reduce maneuverability (of fighter jets)?

In this answer Ethan makes the following statement concerning winglets on fighter jets: [Winglets] reduce maneuverability which is why you don't see a winglet on a fighter jet I could image that ...
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2answers
683 views

What are the effects of adding winglets to an aircraft not designed with winglets originally?

Are there any positive advantages or catastrophic effects on adding winglets to an aircraft not designed with winglets originally?
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3answers
2k views

How is drag created from wingtip vortices?

What is the reason for the drag due to wingtip vortices? This question is about (general) performance, but doesn't answer the drag aspect.
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3answers
3k views

Why are modern aircraft wings often pointed instead being more rectangular?

When viewed from the Z axis (above or below), why are modern aircraft wings often pointed as they get towards the wingtips instead of maintaining the same surface area for their entire length? This ...
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1answer
3k views

Any info on very strange wing endings on this Stemme glider?

Do you have any info on this strange wing endings used on Stemme glider? Source
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1answer
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Why are there different types of winglets? [duplicate]

If all winglets serve the same purpose (to reduce vortex drag), why do different aircraft have different winglets? This question is not trying to get a comparison of the development of winglets/...
8
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1answer
892 views

Is induced drag not caused by tip vortices?

According to most online resources, including NASA, induced drag is caused by wingtip vortices which induce downwash. However, in StackExchange I have found a few answers (Peter's and Jan's) that ...

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