Aerodynamics behind Flying Wings and Tailless Aircraft (Part 2): Stability

[@JinKee]

I’m so glad i found your channel for a detailed aerodynamic breakdown of these topics for the hobbyist

[@StartupChuck]

Thanks for for these videos. It is a great resource in the small niche of tailless aircraft design that is largely ignored. very excited to see more of your wing design and how it performs.

[@陳謹揚-q7e]

Such a high-quality video. Thanks to Gabe, a message from a Taiwanese student who is also majoring in aerospace engineering

[@leaky8]

Gabe, thank you for putting these videos together. I'm not an aerospace engineer but I feel like I learned more in these two videos on aerospace than I did in my entire undergraduate program. Incredible detailed, incredibly in depth, absolutely amazing. Looking forward to future videos! Thank you!

[@gabefpv]

Appreciate that! Glad you found it helpful!

[@RealBMK]

I haven't taken aero yet but I learned so much from this video.

[@matthewallen3375]

Your series is great at explaining the process to go from design tasks through formulas, to virtual models ending with a working test model. I appreciate the depth in this series. I have successfully built a RC Prandlt-D flying wing (no vertical surfaces.) from foam board, as tested and detailed out by Albion Bowers formerly at NASA years ago. I have been trying to simplify the build process so other can easily succesd too, this has been helpful on the quest, thank you.

[@TheLinessCompany]

As someone who had a small Module about flying robotics and fell in love with flying wings, this vid is really awesome! Thanks man. :)

[@jamesomega]

Excellent series! I'm really looking forward to your winglet analysis! I used to make rc wings and have test flown all kinds of weird shapes and angles to dampen adverse yaw but I've never seen the variables and their relationships explained so well. Keep up the great work!

[@fishercawkey]

Well-done. There's clearly a hunger for this type of content on KZbin, as indicated by the view counts on this video and your Part 1.

[@mostowitz84]

Thank you so much for including the explanation of stability derivatives. Looking forward to the other videos!

[@mykolakhrystenko2886]

By far, the best video on KZbin on aerodynamics topic! Thank You for your work! Please continue! Waiting for new detailed series on dynamic stability and winglet design!

[@notravstar]

Great series so far, really enjoying the videos keep making them and you'll blow up

[@II_xD_II]

Subbed for this level of details Keep going mate

[@onlygaming8106]

Plz continue the series it is really helpful

[@grzegorzkolbrecki8344]

Both parts are top notch content, thank You very much!

[@II_xD_II]

Looking forward for whats to come!

[@RafaelSanchez-s3f]

amazing content!!!!!!!!!!! thank you so much for sharing your knowledge with us!!!!

[@Frank-xd4hw]

Pretty good video. Will there be another one in these series? Have you considered doing one on box wings?

[@gabefpv]

Yeah I’ll keep the series going

[@ay_sher]

Good stuff, would love to see how you counter adverse yaw, and produce directional control.

[@rafaelpadilha4585]

Proverse yaw is achieved by ailerons on the tip of the wing, on the part with negative angle of attack. More lift there means forward thrust in that case. There are videos explaining this.

[@ay_sher]

@@rafaelpadilha4585 I guess you're talking about the Prandtl wing and bell shaped wing loading. I have seen the vidoes. But still, YAW CONTROL is missing.

[@jedswift]

Induced drag decreases, not increases with increasing speed. Di = L^2/(πqb^2) or CDi = CL^2/(πA) with q being dynamic pressure, b the wing span, and A as aspect ratio (b^2/wing area).

[@gabefpv]

Whoops, maybe I accidentally said decreases. Totally meant increases! Good catch

[@ilyesouadah7299]

incredible videos! love the detail

[@hu5116]

Hi Gabe, another fantastic video! You are a master of this! So quick question, can you recommend a top couple of books to cover this in some approximate way to how you do here? Or stated another way, what do you recommend in books? Also, I’d like to recommend taking a look at the “Klingberg wing MkII” channel. He has done some really interesting analysis of a famous flying wing failure and his most recent videos have isolate a really interesting root cause phenomena related to Reynolds Number that is really a core lesson in the vagaries of aerodynamics that I think really highlight some of the things you say about verification.

[@gabefpv]

Yessir, there are a few books in the video description

[@hu5116]

@@gabefpv Oooops, sorry missed that! Anyhow your videos are like Tony the Tiger, GREAT! Thanks and look forward to next ones!

[@fikumik]

16:46 does increased speed really increase induced drag? As far as i know the ind drag coeff drops with the velocity as the AOA decreases, so can we be certain that drag as a force raise?

[@gabefpv]

This was an error on my end, Q is in the denominator of the induced drag eq, meaning Di decreases with velocity increases

[@fikumik]

@gabefpv thanks for clarification, great videos tho:)

[@jzerious4523]

What program are you using to simulate the flight characteristics?

[@gabefpv]

Tools like XFLR5, Star-CCM+, Openfoam/fun3d

[@dipesh8836]

Hi, whats the reference area for planes in the drag equation? Generally in cars we use the frontal area but a lot of papers are saying that its the wing area for planes? What is actually the reference area

[@gabefpv]

For drag on bluff bodies like cars or parachutes, frontal area should be used. For drag on streamlined bodies like aircraft, the planform area is used for consistency with the lift equation

[@dipesh8836]

What sort of Cd are you aiming for with this wing? I am personally designing a speeding with a Cd of 0.05 and am currently at 0.083 Edit: can you please help me out a bit? I am currently using a mh60 airfoil with no twist, naca 009 winglets and a frontal area of 0.00876m^2

[@gabefpv]

Making a winglet design video soon, but if your winglets aren’t toed in try to use a cambered airfoil to extract more negative drag (resultant winglet lift vector due to spanwise flow is tilted slightly forward)

[@dipesh8836]

I had another question, do we use the wing area or the frontal area for evaluating drag? From what i know from the automotive side is that the reference area is the frontal area but a lot of the rc plane guys say that its actually the wing area.

[@dzfeverframe6787]

Thank you man ❤

[@BatataKato]

🎉🎉🎉 great video

[@timothyjudson9191]

Hey mate, would you consider doing a video that is self contained and focused on using diagrams to show that the principles discussed are obvious? I kinda get the math, but I get a little lost in some of the jargon. Making it very intuitive would be huge!

[@gabefpv]

Sure thing. Can you elaborate a bit?

[@timothyjudson9191]

@@gabefpv Imagine that someone who has never taken calculus is watching. The basic ideas should (I hope lol) be transmissible without knowing exactly how to predict it. Starting with that makes the math make a lot of sense too. (This is kinda how I approached rigid body mechanics: concept ----> math)

[@gabefpv]

Got it. Maybe after this series I’ll do a side series that’s aimed towards those without engineering or mathematics backgrounds! Thanks for the suggestion

[@timothyjudson9191]

@@gabefpv~ I re-watched at normal speed and it was a lot easier to understand lol. Btw, where do you study?

[@CptPorkster]

The fastest glow up since Mr Beast

[@pranav5777]

can u mention some books to learn this?

[@gabefpv]

@@pranav5777 check out the description

[@pranav5777]

@@gabefpv oh i did see it after writing the comment,sry!

[@varshneydevansh]

subbed

[@mohammad_physics]

How i Contact with you

[@gabefpv]

[e-mail]

[@NinaNime-eh7ew]

Dude plz, maybe can you look into upside down v tails

[@gabefpv]

Sure thing

[@nidhinkn5980]

Think three forward and backward .

[@KlingbergWingMkII]

This design will be very, very spin prone due to size, shape, and location of the elevons.

[@gabefpv]

I agree, because i designed the example wing in a couple of minutes. Definitely needs twist and sweep optimization

[@shayankumarnag8650]

Hello sir

[@gabefpv]

Hello my friend

[@shayankumarnag8650]

@@gabefpv sir would you teach me this course please 🙏🙏🙏

[@sashgorokhov]

This one is too theoretical for me. I wish you dived more into practical side of things that can be applied by hobbyists like me

[@gabefpv]

You can design a plane and have these values in XFLR5 in a matter of minutes. If you know what you are looking for in static and dynamic stability modes, you can cut out a whole lot of trial and error when designing RC planes. The videos on fabrication and flight testing are coming soon, too. Just can’t ignore stability when properly designing.

[@gabefpv]

24:30 is about as practical as you can get before just attempting flight with no stability checks (such as only checking CG location on an RC)

[@professionalprocrastinator8103]

I don't agree @sashgorokhov, the theoretical grounds are extremely handy for this one video. I'm saying that as someone who wants to understand more about the stability of flying wings as a flight sim dev. Keep going Gabe, this is a gem

[@MattExzy]

I've always found flying wings to be black magic. Nice to have an understanding of the 'why' vs. just whacking on a flight controller, loading firmware, setting pitch & roll limits, and going full send.

[@miguelcanoe6774]

The well is deep. Very deep. The surface of the water in the well is as close as the rain brings it. Dig away the hill