EAA 2016 founders Inovation Competition

[jedi]

The application window is about to close (June first). The goal, "To reduce the in-flight loss of control accident rate" by inspiring the design and development of new technology for experimental aircraft builders.

I understand there are 60 + entrants. Has there been any prior discussion on the competition?

Any comments from participants?

Any good ideas?

 

[Victor Bravo]

My wife wants me to submit my invention ( EZ Flap Home ) but I'm guessing that they want something with more "wow" factor.

 

[jedi]

Is this more of a Wow?


Wing Induced Thrust - Improving Aerodynamic Control


Abstract

Wing induced thrust (WIT) is a result of modifying the wings span wise lift distribution to recover energy from the inboard lifting wing segment with an outboard wing segment which produces both thrust and lift. This thrusting wing segment can be used to create a rolling moment without creating the adverse yaw moment of typical ailerons, thus improving aircraft control and handling characteristics. This modified wing can provide improved performance as well as positive yaw stability at high angles of attack and into a progressive wing stall, to reduce or eliminate the tendency for the stall to develop into a spin. The overall result is expected to be an improvement in Loss of Control (LOC) accident statistics.
The primary reason for aircraft in-flight LOC accidents is a stall-spin entry with insufficient altitude for recovery. Experimental Amateur Built (EAB) aircraft incorporating wing designs that offer a progressive stall will provide an opportunity for stall recovery. Improving high-alpha yaw stability and roll control will result in fewer LOC incidents. We are proposing to incorporate new wing tip technology on EAB aircraft that will improve the aerodynamics of basic wing structures. The aerodynamic changes will improve aircraft control and safety in a manner that is acceptable to both the home builder and kit manufacturer.
To accomplish the safety goal, the new technology must not result in performance degradation to the aircraft in normal operation. It also must not add to cost or build time unless the change is offset by an acceptable balance of performance gains.
Our wing technology is most effective on the constant-chord and untwisted-wing designs used on many EAB aircraft such as Van's RV aircraft series, the Glasair Sportsman, Cub type aircraft and many others. However, it will also be effective on other wing plan-forms that do not already incorporate an advanced wingtip device (winglet). We have worked with constant-chord and untwisted wings for many years. Through the use of crescent shaped wing tip extensions, we have achieved significant performance improvements while also improving the yaw stability and stall characteristics of the wing. With the use of this simple and inexpensive solution, the primary aircraft structure of common EAB aircraft designs can be maintained while the aircraft's stall/spin characteristics are improved, resulting in fewer LOC incidents.
With further development, much larger efficacy may be achieved by incorporating the aircraft roll control into the geometry of the wing tip device. This may eliminate state-of-the-art ailerons from the wing, simplifying aircraft construction and reducing cost. It may also significantly reduce or eliminate the typical adverse yaw which is often a contributing factor for a stalled wing initiating a potentially dangerous spin.

What do you all think?

 

[Victor Bravo]

The entire abstract does not specify what exactly this innovation does, how it accomplishes what it claims to do, and in general talks around in circles... you have more questions after you read it than before.

All I got out of it is "crescent shaped wingtips" are involved, but I came away with no understanding of why, how, or when they work. I did not understand whether the crescent shape was in planform, or whether it was being viewed from the front/back.

I'm NOT saying that their idea is BS, I'm saying they did a horrible job of explaining what they were proposing.

 

[BBerson]

Where did you find that abstract?

 

[TahoeTim]

I submitted my 1946 Ercoupe :roll:

 

[BoKu]

...What do you all think?

Translated: "A bit more aspect ratio might help."

The aero guy I work with, who published a thesis that showed that the most efficient planform (top view) for an elliptically-loaded wing panel is essentially a quarter-ellipse with a straight trailing edge, just rolls his eyes at every new proposal for a wingtip. Bottom line, there's not much you can do with that little bit of wing that will make much difference. Besides, of course, making it longer.

 

[Wayne]

My wife wants me to submit my invention ( EZ Flap Home ) but I'm guessing that they want something with more "wow" factor.

Cool - you are the EZ Flap guy! Unless you are the lady on your website, of course! :ban:

 

[Mavigogun]

Bottom line, there's not much you can do with that little bit of wing that will make much difference. Besides, of course, making it longer.

Not to jack the thread, but the Prandtl-D plane form seems to have successfully surpassed the ellipse with a bell lift distribution, no?

 

[BoKu]

Not to jack the thread, but the Prandtl-D plane form seems to have successfully surpassed the ellipse with a bell lift distribution, no?

Well, yes and no. Yes, they have demonstrated greater efficiency in certain flight envelopes. However, I don't think that the solution is universally applicable.

 

[autoreply]

Translated: "A bit more aspect ratio might help."

The aero guy I work with, who published a thesis that showed that the most efficient planform (top view) for an elliptically-loaded wing panel is essentially a quarter-ellipse with a straight trailing edge, just rolls his eyes at every new proposal for a wingtip. Bottom line, there's not much you can do with that little bit of wing that will make much difference. Besides, of course, making it longer.

But why make that assumption, or was the underlying assumption a planar wing?

The results from "unrestrained" optimization for lowest bending moment, profile drag and induced drag invariably lead to a super-elliptical top- and frontal view with a polyhedral wing, or even a slight C-wing. Harder to make admittedly, and sure a hell of a lot harder to design right...

 

[Victor Bravo]

Cool - you are the EZ Flap guy! Unless you are the lady on your website, of course! :ban:

Shhhh... quiet! If I get found out, the guys from one or two of the other forums will come after me here and throw a rope over a tree branch! I get in enough trouble here discussing experimental stuff already. Can you imagine if I had to fight off those guys plus the people here ?

The girl on the website is a friend of ours, and for some strange reason people really seem to enjoy looking at her more than they enjoyed looking at me at the trade shows. Never did figure that out...

 

[cluttonfred]

My wife wants me to submit my invention ( EZ Flap Home ) but I'm guessing that they want something with more "wow" factor.

An actual product already in use and for sale should be worth at least ten unimplemented bright ideas. I say go for it. And ****, I was hoping you were the spokesmodel. ;-p

 

[Victor Bravo]

Thank you Matthew, that little idea turned into a very successful thing for me, although I put some expectations on it (and on some of my fellow aviators) that were not totally realistic and did not address human nature. No fault of the product, it has bought my little 172 four or five times over. But the EAA "prize" is for experimental airplanes, so I'm DQ'ed.

 

[jedi]

Where did you find that abstract?

I am a consultant on the project.

 

[Victor Bravo]

With all sincere respects, I believe they need some help in the comm's department if they want to make it palatable for funders, award committees, professional review, etc.

For example, creating thrust at the wingtip will not create a rolling moment nearly as much as a yawing moment. Even if yaw eventually couples into a rolling motion, it needs to be explained in more detail. In this example it also should be addressed why and how the thrust created at the wingtip is better than the yaw created by a rudder.

Does anyone else here remember that brilliant humorous description written by a (presumably disgruntled) Scaled employee where he explains Rutan's discovery of "intersection thrust" as a by-product of his propensity to design aircraft without no regard for the number of intersections?

 

[jedi]

The entire abstract does not specify what exactly this innovation does, how it accomplishes what it claims to do, and in general talks around in circles... you have more questions after you read it than before.

All I got out of it is "crescent shaped wingtips" are involved, but I came away with no understanding of why, how, or when they work. I did not understand whether the crescent shape was in planform, or whether it was being viewed from the front/back.

I'm NOT saying that their idea is BS, I'm saying they did a horrible job of explaining what they were proposing.

VB Thanks so much for your reply. I found it useful and will post a revision based on your comments. There is a 800 word limit on the abstract. The abstract posted was well below that theorizing that less is better. I understand your desire for more information. That is what the full report is for. I have pulled segments from the above post that I feel address your questions. I doubt that will fully satisfy your comments so more will follow.

what exactly this innovation does - crescent shaped wing tip extensions improve the aerodynamics of basic wing structures; create a rolling moment without creating the adverse yaw moment of typical ailerons; Improving high-alpha yaw stability and roll control; eliminate state-of-the-art ailerons from the wing, simplifying aircraft construction

how it accomplishes what it claims to do - with crescent shaped wing tip extensions the primary aircraft structure of common EAB aircraft designs can be maintained while the aircraft's stall/spin characteristics are improved; modifying the wings span wise lift distribution to recover energy from the inboard lifting wing segment with an outboard wing segment which produces both thrust and lift; eliminate the typical adverse yaw which is often a contributing factor for a stalled wing initiating a potentially dangerous spin.

when they work - at high-alpha; at high angles of attack and into a progressive wing stall, When applied to "many EAB aircraft such as Van's RV aircraft series, the Glasair Sportsman, Cub type aircraft"

 

[jedi]

Translated: "A bit more aspect ratio might help."

The aero guy I work with, who published a thesis that showed that the most efficient planform (top view) for an elliptically-loaded wing panel is essentially a quarter-ellipse with a straight trailing edge, just rolls his eyes at every new proposal for a wingtip. Bottom line, there's not much you can do with that little bit of wing that will make much difference. Besides, of course, making it longer.

How much longer? The typical wing tip is a foot or two. High performance droop tips might add 2 or three feet. 737 winglets add about 7 feet possibly more. Adding 4 feet to a Sonex might make a significant difference if it also applies different aerodynamic principles to the basic wing structure.

 

[Victor Bravo]

Sorry I could not continue the conversation yesterday, no offense or lack of interest on my part. Phone calls at work vs. quiet e-mail correspondence, household chores, and other impediments were in play.

From a proposal (pronounced "sales") standpoint there are still a couple of things that I am guessing might have made better use of the 800 word space you were given for an abstract. Not because you don't know what your invention does, but because the reader doesn't.

The full proposal becomes irrelevant if the abstract does not grab the attention, then win the support of the reader. "Less is more", SOMETIMES, but that principle applies to confusion and questions as much as it does to information

If you were responsible for the stewardship and expenditure of any significant amount of money, would you want to understand more about what you were buying or less?

If any significant number, out of a group of fairly educated airplane people (HBA), doesn't immediately get the concept and why it is an improvement, then IMHO you have a problem to address. So perhaps you might think of polling the group to see whether other reasonably experienced people feel that the abstract is missing something. I could easily be wrong about this,a nd will admit it with sincerity if that is the case.

 

[jedi]

I have added additional information in the bold print below. (Guess the bold did not work.) Additional comments?


Abstract

Wing induced thrust (WIT) is a result of modifying the wings span wise lift distribution to recover energy from the inboard lifting wing segment with an outboard wing segment which produces both thrust and lift. This thrusting wing segment can be used to create a rolling moment without creating the adverse yaw moment of typical ailerons, thus improving aircraft control and handling characteristics. This modified wing can provide improved performance as well as positive yaw stability at high angles of attack and into a progressive wing stall, to reduce or eliminate the tendency for the stall to develop into a spin. The overall result is expected to be an improvement in Loss of Control (LOC) accident statistics.

The primary reason for aircraft in-flight LOC accidents is a stall-spin entry with insufficient altitude for recovery. Experimental Amateur Built (EAB) aircraft incorporating wing designs that offer a progressive stall will provide an opportunity for stall recovery. Improving high-alpha yaw stability and roll control will result in fewer LOC incidents. We are proposing to incorporate wing tip technology on EAB aircraft that will improve the aerodynamics of basic wing structures. The aerodynamic changes will improve aircraft control and safety in a manner that is acceptable to both the home builder and kit manufacturer.

To accomplish the safety goal, the new technology must not result in performance degradation to the aircraft in normal operation. It also must not add to cost or build time unless the change is offset by an acceptable balance of performance gains.

[/B]Many EAB aircraft have a constant chord and untwisted-wing sometimes referred to as a Hershey Bar Wing (HBW). This design is selected because it is easily and accurately constructed without the use of jigs and complicated tooling. A side benefit is that it has a progressive stall that is recognizable and avoidable. However, once the wing is stalled it becomes unstable in yaw and roll and has a tendency to enter a spin unless prevented by decisive pilot input to counter the roll and yaw of a dropping wing.

Our work in fluid dynamics has demonstrated significant performance improvements while also improving the yaw stability and stall characteristics of this type of wing. Through the use of crescent plan form wing tip extensions utilizing the Prandtl/Horten developed Bell Shaped Lift Distribution (BSLD) applied to a constant cord zero twist wing the progressive stall of the HBW can be retained and the favorable roll/yaw characteristics of the BSLD can provide a synergistic improvement to the high alpha wing characteristics. This would provide a dramatic improvement in overall wing performance and stability up to and through the stall that could prevent LOC accidents.

This wing technology is most effective on the constant-chord and untwisted-wing designs used on many EAB aircraft such as Van's RV aircraft series, the Glasair Sportsman, Cub type aircraft and many others. However, it will also be effective on other wing plan-forms that do not already incorporate an advanced wingtip device (winglet). With the use of this simple and inexpensive solution, the primary aircraft structure of common EAB aircraft designs can be maintained while the aircraft's stall/spin characteristics are improved, resulting in fewer LOC incidents. [/B]

With further development, much larger efficacy may be achieved by incorporating the aircraft roll control into the geometry of the wing tip device. This may eliminate state-of-the-art ailerons from the wing, simplifying aircraft construction and reducing cost. It may also significantly reduce or eliminate the typical adverse yaw which is often a contributing factor for a stalled wing initiating a potentially dangerous spin.