Author Topic: All in One (Read 10366 times)

Admin · « **on:** July 21, 2023, 07:24:29 AM »

Hey guys,

This new foil design has an 800 mm span lower wing with 1220 area. The two upper wing sections are the stabilizers so, unlike the Falcon design, no fuselage or tail wing is needed. Inspired by the Synergy aircraft design below which I find amazing. Part one is printing now.

exiled · « **Reply #1 on:** July 22, 2023, 10:43:08 PM »

I was just telling someone the other day that I thought foil design was going to plateau pretty soon. I guess those words are as good as eaten. Looks like wing tip breaches all over the place though.

Admin · « **Reply #2 on:** July 23, 2023, 07:42:11 AM »

Quote from: exiled on July 22, 2023, 10:43:08 PM

I was just telling someone the other day that I thought foil design was going to plateau pretty soon. I guess those words are as good as eaten. Looks like wing tip breaches all over the place though.

Yes! There are a number of ways to do closed wings and I want to try them all. We are certain to find the shortcomings of each

.

This is what got me interested in this double box. https://www.aero-mag.com/box-tail-wing-developments-synergy-aircraft Mine is quite different but it does share the dual downlifting horizontals.

This is a possibly more efficient alternative to using a single flying wing with a lot of reflex like the Triton guys are doing (nicely).

burchas · « **Reply #3 on:** July 23, 2023, 11:46:55 AM »

Quote from: Admin on July 23, 2023, 07:42:11 AM

Quote from: exiled on July 22, 2023, 10:43:08 PM
I was just telling someone the other day that I thought foil design was going to plateau pretty soon. I guess those words are as good as eaten. Looks like wing tip breaches all over the place though.

...We are certain to find the shortcomings of each .

This design is fascinating

Wondering if you ran any flow analysis with mast included in the formula? It reminds me a flow issue I ran into a while back running three vertical objects in such close proximity.

Admin · « **Reply #4 on:** July 23, 2023, 01:39:46 PM »

No real flow analysis other than what is available online for the unedited airfoils that I am using.

I too am interested in what the yaw control will be like. In my mind, we take a lot of the mast's yaw resistance out of the equation when we direct mount (bringing the mast very close to the yaw axis), leaving us to fine tune yaw with other verticals (in this case four so far). The plane has active controls and is, of course, very different in many ways, but I thought it was interesting that they added those strakes. We can sure do that and in general this file can be veery easily modified as needed later. I have a lot of questions and the likelyhood that this first attempt will be perfect is zero, but we have a start point.

surfcowboy · « **Reply #5 on:** July 24, 2023, 01:43:13 PM »

One thing I love here is the idea that there is no need to be right. I appreciate that folks are letting admin just make stuff and refine this process without the weight of every foil being a hit or even working.

The quick(-ish) relatively low labor prototypes are the thing here more than the actual foils themselves. Kudos to the forum for getting onboard with this.

But man would it be cool to see one be a game changer.

PonoBill · « **Reply #6 on:** July 24, 2023, 05:28:14 PM »

Actually, I don't think you'd need to worry about breaching. This design should benefit from the same lift self-regulating as ladder foils do. As speed increases there is less surface area required (lift is a function of velocity squared, so that's a big deal). The wing doesn't come out of the water to lose lift--just being close to the surface should ventilate the top wing.

exiled · « **Reply #7 on:** July 24, 2023, 10:16:32 PM »

Quote from: PonoBill on July 24, 2023, 05:28:14 PM

Actually, I don't think you'd need to worry about breaching. This design should benefit from the same lift self-regulating as ladder foils do. As speed increases there is less surface area required (lift is a function of velocity squared, so that's a big deal). The wing doesn't come out of the water to lose lift--just being close to the surface should ventilate the top wing.

I was more thinking about tip breaches in turns. Good breach recovery is a killer feature, but having the top wing that much higher means you won't be able to roll as far.

Admin · « **Reply #8 on:** July 25, 2023, 04:26:53 AM »

Quote from: exiled on July 24, 2023, 10:16:32 PM

Quote from: PonoBill on July 24, 2023, 05:28:14 PM
Actually, I don't think you'd need to worry about breaching. This design should benefit from the same lift self-regulating as ladder foils do. As speed increases there is less surface area required (lift is a function of velocity squared, so that's a big deal). The wing doesn't come out of the water to lose lift--just being close to the surface should ventilate the top wing.

I was more thinking about tip breaches in turns. Good breach recovery is a killer feature, but having the top wing that much higher means you won't be able to roll as far.

You could make the case that we have the ultimate fences (and therfore ventilation protection) in place with the closed wingtips and mid wing verticals of this design.

. Also, the surface which would actually breach first in a banked turn is a single stabilizer tip (small inverted wing). That has the low pressure side down, and the internal fence should keep the ventilation from travelling down the wing. Lastly, closed wing designs should theoretically allow the use of shorter span wings without sacrifice due to drag reduction and efficiencies. This wing is 800 mm. That obviously is a big benefit as short span wings take a much steeper banked turn to pierce at all.

Is all of that true? Shit if I know

https://www.sciencedirect.com/science/article/abs/pii/S0029801818313234

Admin · « **Reply #9 on:** July 25, 2023, 05:00:24 AM »

I am really interested to see how the onboard stabilizers do in managing pitch. I have all of the measurements, specs, airfoil (best guess), and speeds for the Synergy plane and can use Reynolds, wing loading info, and real world comparison to known-good conventional (production) wings to adjust air to water and get a basic plan. I think I am in the range there, but that is just a start. There is no way it is going to be perfect right off. There are just too many unknowns. My goal is to get the first one built, hope it flies, hope it holds together, hope I can see what can be improved on the next one.

Dwight (DW) · « **Reply #10 on:** July 25, 2023, 07:48:05 AM »

Those fences are what GoFoil has on the front wings. He said they were first used in kite racing back in the day.

Admin · « **Reply #11 on:** July 30, 2023, 06:42:04 AM »

Here is the next batch of prints. In back is the Synergy inspired double box (All In One, No Fuse or Stabilizer) that I mentioned a few days ago. Code name Eldorado

. The internal carbon tubes are all cut and inserted, so she is ready for bonding.
In the middle is the first major revision of the Falcon Foil. There is a newer stiffer fuse joint, a single 6 mm screw fuse removal point, and a number of small form tweaks to clean up flow. She is also ready for bonding.
The little guy up front is a 20% larger Infinity tail for the new fuse design on the Falcon. I have also done 3 other tails for that system and bonded up 3 fuse lengths

Admin · « **Reply #12 on:** August 30, 2023, 03:10:37 PM »

Here is the Eldorado, all finished up and ready for testing. She is 800 mm and weighs 4.2 lbs as she sits. Thought I better shoot a couple of beauty shots before I drop her 🙂.
Thanks for looking!