4 ms·

An airfoil that will never stall, no matter the angle of attack

47 points by andrewfarah 12y ago

AlexeyBrin 12y ago
The title is a bit sensationalist - An airfoil that will never stall, no matter the angle of attack. They did CFD simulations that shows their wing not stalling at extreme angles of attack (not at any angle). Also, they are talking about a wing. An airfoil is a wing section not the actual wing.
- ibisum 12y ago
  An airfoil describes the stall characteristics of the wing. Camber, chord, edges, angle of attack .. these are all described by the airfoil and are key to flight control, including stall handling. How an airfoil gets itself out of the stall state is of great interest to designers. Airfoils which utilize the Magnus effect (as in this case) do have different stall characteristics. Its not incorrect to refer to the airfoil in that context.. a bit like calling a soccer ball not just a sphere but also a wing, too, which in fact it is to most airfoil designers .. ;)
ridgeguy 12y ago
This reminds me of the Boeing YC14 blown wing (1). It looks a little like a fully structure-contained implementation of that concept. (1) http://en.wikipedia.org/wiki/Boeing_YC-14 http://en.wikipedia.org/wiki/Boeing_YC-14
- Crito 12y ago
  Kind of reminds me of a lot of ekranoplan designs.
callesgg 12y ago
Not entirely correct as turning it over 90 degrees does not apear to work.
simonblack 12y ago
There is a difference between stalling due to high angles of attack, and having too much drag from cross-sectional resistance on an unstalled wing to be able to lift. The practical outcome is the same however, not enough lift to overcome the weight.
- Alupis 12y ago
  Or not enough airspeed, which is the most common stall condition real pilots face (caused by a variety of scenarios such as too much altitude, runway approach too slow, etc).
awjr 12y ago
Rather than kill the site (as the video is a downloadable 27mb file), I've uploaded it to youtube https://www.youtube.com/watch?v=frgCQVGOdgs&feature=youtu.be https://www.youtube.com/watch?v=frgCQVGOdgs&feature=youtu.be I'll delete it in a couple of days once this drops off HN.
fit2rule 12y ago
I'm reminded of some of the other attempts to utilize the Magnus effect: https://www.youtube.com/watch?v=kgOAwzG9Fd0 https://www.youtube.com/watch?v=kgOAwzG9Fd0 https://www.youtube.com/watch?v=_BDCcSR1pJ4&list=PLB851DC7DF2995130 https://www.youtube.com/watch?v=_BDCcSR1pJ4&list=PLB851DC7DF... https://www.youtube.com/watch?v=acXvl-8xrBM https://www.youtube.com/watch?v=acXvl-8xrBM Very interesting flight mechanics are possible when designers try to utilize this effect, and its exciting to see this little-known technology come to the forefront as more and more folks enter the 'drone-fleets are the new network' age ..
lotsofmangos 12y ago
Cool, is fairly similar to the fanwing configuration. http://www.fanwing.com/ http://www.fanwing.com/
deleted 12y ago
[deleted]
staz 12y ago
Could a (2010) be added to the title? The website don't seem to have been updated since then
- Aerohead 12y ago
  The website hasn't been updated in a while, but I assure you that development is still going on.
larrydag 12y ago
I wonder how it performs when there is power failure? Does it glide well?
- Aerohead 12y ago
  Absolutely not. To glide well, you need big ol' wings. There's a concept called aspect-ratio, which is basically the relationship between the wingspan (left to right) and wing chord (front to back). High AR = better for gliding. Conversely, and in the case of the mini-PW, when you have virtually no wingspan, you aren't going to glide very far. We affectionatly referred to power loss as "brick mode".
  - larrydag 12y ago
    So i suppose you could design a trade-off or balance. Increase AR while reducing the size of the mangus effect airfans.
    - Aerohead 12y ago
      Well ideally we wouldn't lose power to begin with but yes. The PW is essentially a powered wing to begin with, so losing power leaves you with just a wing. The real design benefit here is that with the powered wing, you can make the win extra thick. And I can tell you, that internal space is huge. Plenty of room for any kind of payload.
Aerohead 12y ago
Hey guys, I worked on this program as an intern in my senior year of college (2012-2013). There are 5 units of the mini-PW's out right now for testing, and I've built all of them. I can answer any questions you might have and I'll do my best to explain the aerodynamics behind it if anyone is interested!
- TheLoneWolfling 12y ago
  What does the list-to-drag ratio versus AOA curve look like?
  - TheLoneWolfling 12y ago
    *lift, sorry about that. And I'd actually be interested in both the lift curve and the drag curve, as well as lift/drag.

47 points by andrewfarah 12y ago

The title is a bit sensationalist - An airfoil that will never stall, no matter the angle of attack. They did CFD simulations that shows their wing not stalling at extreme angles of attack (not at any angle). Also, they are talking about a wing. An airfoil is a wing section not the actual wing.

ibisum 12y ago
An airfoil describes the stall characteristics of the wing. Camber, chord, edges, angle of attack .. these are all described by the airfoil and are key to flight control, including stall handling. How an airfoil gets itself out of the stall state is of great interest to designers. Airfoils which utilize the Magnus effect (as in this case) do have different stall characteristics. Its not incorrect to refer to the airfoil in that context.. a bit like calling a soccer ball not just a sphere but also a wing, too, which in fact it is to most airfoil designers .. ;)

ridgeguy 12y ago

This reminds me of the Boeing YC14 blown wing (1). It looks a little like a fully structure-contained implementation of that concept. (1) http://en.wikipedia.org/wiki/Boeing_YC-14 http://en.wikipedia.org/wiki/Boeing_YC-14

Crito 12y ago
Kind of reminds me of a lot of ekranoplan designs.

callesgg 12y ago

Not entirely correct as turning it over 90 degrees does not apear to work.

simonblack 12y ago

There is a difference between stalling due to high angles of attack, and having too much drag from cross-sectional resistance on an unstalled wing to be able to lift. The practical outcome is the same however, not enough lift to overcome the weight.

Alupis 12y ago
Or not enough airspeed, which is the most common stall condition real pilots face (caused by a variety of scenarios such as too much altitude, runway approach too slow, etc).

awjr 12y ago

Rather than kill the site (as the video is a downloadable 27mb file), I've uploaded it to youtube https://www.youtube.com/watch?v=frgCQVGOdgs&feature=youtu.be https://www.youtube.com/watch?v=frgCQVGOdgs&feature=youtu.be I'll delete it in a couple of days once this drops off HN.

fit2rule 12y ago

I'm reminded of some of the other attempts to utilize the Magnus effect: https://www.youtube.com/watch?v=kgOAwzG9Fd0 https://www.youtube.com/watch?v=kgOAwzG9Fd0 https://www.youtube.com/watch?v=_BDCcSR1pJ4&list=PLB851DC7DF2995130 https://www.youtube.com/watch?v=_BDCcSR1pJ4&list=PLB851DC7DF... https://www.youtube.com/watch?v=acXvl-8xrBM https://www.youtube.com/watch?v=acXvl-8xrBM Very interesting flight mechanics are possible when designers try to utilize this effect, and its exciting to see this little-known technology come to the forefront as more and more folks enter the 'drone-fleets are the new network' age ..

lotsofmangos 12y ago

Cool, is fairly similar to the fanwing configuration. http://www.fanwing.com/ http://www.fanwing.com/

deleted 12y ago

[deleted]

staz 12y ago

Could a (2010) be added to the title? The website don't seem to have been updated since then

Aerohead 12y ago
The website hasn't been updated in a while, but I assure you that development is still going on.

larrydag 12y ago

I wonder how it performs when there is power failure? Does it glide well?

Aerohead 12y ago
Absolutely not. To glide well, you need big ol' wings. There's a concept called aspect-ratio, which is basically the relationship between the wingspan (left to right) and wing chord (front to back). High AR = better for gliding. Conversely, and in the case of the mini-PW, when you have virtually no wingspan, you aren't going to glide very far. We affectionatly referred to power loss as "brick mode".
- larrydag 12y ago
  So i suppose you could design a trade-off or balance. Increase AR while reducing the size of the mangus effect airfans.
  - Aerohead 12y ago
    Well ideally we wouldn't lose power to begin with but yes. The PW is essentially a powered wing to begin with, so losing power leaves you with just a wing. The real design benefit here is that with the powered wing, you can make the win extra thick. And I can tell you, that internal space is huge. Plenty of room for any kind of payload.

Aerohead 12y ago

Hey guys, I worked on this program as an intern in my senior year of college (2012-2013). There are 5 units of the mini-PW's out right now for testing, and I've built all of them. I can answer any questions you might have and I'll do my best to explain the aerodynamics behind it if anyone is interested!

TheLoneWolfling 12y ago
What does the list-to-drag ratio versus AOA curve look like?
- TheLoneWolfling 12y ago
  *lift, sorry about that. And I'd actually be interested in both the lift curve and the drag curve, as well as lift/drag.