Delanne Tandem Wing Project

[Monte.C]

Of so-called Nenadovich biplane or tandem wing configuration, the tandem-mounted wings providing a continuous slot effect and offering exceptional center of gravity range.

Relative angle of attack between the upstream and downstream airfoils (δ = α w α p ), where each angle of attack is taken with respect to the free stream. The decalage is therefore positive if the forewing incidence is greater than that of the rearwing or negative if the converse is true.

Positive decalage results in greater lift from the upper wing than the lower wing, the difference increasing with the amount of decalage (angle difference between the upper and lower wings chords)
In a survey of representative biplanes, real-life design decalage is typically zero, with both wings having equal incidence. A notable exception is the Stearman PT-17, which has 4° of incidence in the lower wing, and 3° in the upper wing. Considered from an aerodynamic perspective, it is desirable to have the forward-most wing stall first, which will induce a pitch-down moment, aiding in stall recovery. Biplane designers may use incidence to control stalling behavior, but may also use airfoil selection or other means to accomplish correct behavior.

For me, is seems the older dual-wing configurations is more of "STOL" capacity than speed.. even if such configuration give possibility for thinner airfoils, and less wingspan and smaller plane (aka speed and then quicker maneuverability eg.). And that the CG point get easier eg. by loads, so isnt as necessary to place it at actual point.
By some theories though, its mentioned that the room between for & aft "wings" can help less drag, and in subsonic we can today see lot of plane designs with a tandem systems, even if is just canards (who also is a tandem-wing versions)

Now you're speaking my language. Very helpful. Thank you!

 

[leaded50]

also a technical science report on a British dual-wing plane: https://www.aerosociety.com/media/4...la-tandem-wing-aircraft-concept-1941-1947.pdf

 

[leaded50]

and... a funny control.. the de Delanne´s planes (confirmed at least on the 20-T) had ailerons/flaps/elevators on both wings, or flaps on front, ailerons at back wing. Think about the "weird" flyingaction you can get by elevators on both wings.... flaperons fun

 

[Monte.C]

and... a funny control.. the de Delanne´s planes (confirmed at least on the 20-T) had ailerons/flaps/elevators on both wings, or flaps on front, ailerons at back wing. Think about the "weird" flyingaction you can get by elevators on both wings.... flaperons fun

Wow, LOADS of control. Those guys were saying "Hey look what I can do!"

 

[synjin]

leaded50, thanks for the information. I'm half way into my twin design, so the more information to work from the better. It will have a 45" front wing, probably about 30" long, a pair of 2212 1000Kv motors with differential thrust. I'd like to do a Master Series style fuselage for it.

In any case, I wondered if you fellows would look at my plans for the Delanne-Long DL-57 Mk.III (I'm 57...so, DL-57.) to see if I missed anything. I put it on a standard Sponz 34"x22" sheet. In Adobe Acrobat Reader DC it prints out on 12 tiled pages. Should anyone want to use them, here they are.

Edit: Changed the dihedral gage and added a faint gray grid to make it easier to line up tiled pages.
Edit: Added the tiled plans, but forgot the dihedral gage. I put a 2 inch lift dihedral into the rear wing.

 

[leaded50]

In any case, I wondered if you fellows would look at my plans for the Delanne-Long DL-57 Mk.III (I'm 57...so, DL-57.) to see if I missed anything. I put it on a standard Sponz 34"x22" sheet. In Adobe Acrobat Reader DC it prints out on 12 tiled pages. Should anyone want to use them, here they are.

Looks ok, no missing parts for me. Perhaps made the dihydral gauge for rear wing either angled, or note on direction in use?

I always do a lot of research when making a plane from scratch with missing plans. I wanna know most, to ensure i get it right, or know what to adjust to fit RC use best. Your welcome on the info

 

[leaded50]

Delanne had a few different planes at idea. The 10-T flew, and was hard tested by the Germans under the war, nobody know where it is today. But a bit similarity to the fantasy plane you pictured, just that the 10-T have the seagull wing. a 2 seater with rear gunner

 

[leaded50]

a few more versiopns here

 

[varg]

Very cool. My senior design project was a tandem wing VTOL UAV. Where did you wind up putting the CG? A small scale foamboard model is how we determined where to put the CG on the plane, though my calculations were not far off. Tandem wings are cool but the models at least seem to be more susceptible to disturbance by wind than conventional planes in my experience.

 

[synjin]

leaded50: I'll fix the dihedral gage. I also wanted to add a rear wing cradle to hold the rear wing in position while gluing it in place. Love those other images. As I go forward designing rc planes, I can use all the interesting ideas I can get.

varg: The CG on the Mk.III is 2.8 inches back from the front wing leading edge. That puts the CG near the middle of the airplane length. I used this CG calculator and the caculated CG has worked out so far. https://rcplanes.online/cg_calc.htm

 

[synjin]

leaded50, I like the swept-wing design above and have a couple of 50mm EDFs to try that with. That would be after I get finished with the twin design.

 

[leaded50]

leaded50, I like the swept-wing design above and have a couple of 50mm EDFs to try that with. That would be after I get finished with the twin design.

you too?? ha,ha

 

[synjin]

Okay, I must be tandem wing mad. I started a DL-250 pusher plan today. The plan is for 48” front wings, about 48” length, and maybe a 3508 motor (though that might be overkill). If I did flaps (front and back wings) that would be 8 servoes. If it flies, it would be a beast!

 

[leaded50]

Okay, I must be tandem wing mad. I started a DL-250 pusher plan today. The plan is for 48” front wings, about 48” length, and maybe a 3508 motor (though that might be overkill). If I did flaps (front and back wings) that would be 8 servoes. If it flies, it would be a beast!

ill bet, it can fly!

 

[leaded50]

here you got a nice painting of it.. (or a version)

 

[Monte.C]

here you got a nice painting of it.. (or a version)
View attachment 177165

Into the space age!

 

[leaded50]

Into the space age!

rare to see a close to todays style of a jetplane, as a pusher as in back of picture.... someone had a unclear crystalball to look in?

 

[Monte.C]

rare to see a close to todays style of a jetplane, as a pusher as in back of picture.... someone had a unclear crystalball to look in?

It just makes me feel like that whole era was about all sorts of modern new design - freedom of design in everything, not just planes. The 50s, 60s, into the 70s.

 

[PsyBorg]

It just makes me feel like that whole era was about all sorts of modern new design - freedom of design in everything, not just planes. The 50s, 60s, into the 70s.

That is because people tried things on their own and did not "Cookie Cutter" everything or just copy someone else who actually DID the work back in those days. They didnt walk around stoned all day (just mostly drunk hehe) and had a little self value and ambition left.

 

[synjin]

Made the right front wing tonight in Master Series style. Looks good. I'll finish the left side and see what they look like joined, then I'll draw up the back wing. I sketched the fuselage with former stations and a box central spine. I'm still trying to think through the transitions from the fuselage skin into the the wings. I'm not going to put flaps on the first plane, and will save that for down the road.

I may go back and reconfigure the twin Delanne plans for Master Series wings instead of folded ones. I was going to do the fuselage MS on that, so I might as go whole hog and do the entire aircraft MS.