What makes our flight controls different 

It's bright white, lol.

​@@FarmerFpvplenty of other white planes out there

I agree. I imagine there's a small aerodynamic penalty to using split rudders. I'm pretty sure the split rudder has more drag in use than a conventional rudder. Having a speed brake likely makes any loses worth it.

Was wondering if that could be a replacement for ... flaps. Thoughts?

@@fdelacou- It could replace flaps for giving drag while reducing altitude without gaining airspeed. Won’t add lift for slower takeoff and landing speeds though.

No! Not sick but good!

@@fdelacou NO. Flaps increase lift and drag, important to minimize and bleed KE during landing. Lift is critical for this. Flap extension is typically not allowed at high speeds due to high loading they can create.

- How I heard it, the rudders are independent - with only a pull cable (spring return to centre) - ??, is the rudder deviation only from centre to full lateral deflection (left or right) ? - OR having no centre stop, the lee side rudder (low pressure) just follows the pressure side (half) to full deflection under spring action? - using the airbrakes on a steep straight-in approach sounds kind of similar to balancing regular toebrakes for yaw control, from the sound of it.. hmmm... Some high performance lightweight RC craft also only use a (single acting) pull cable (kevlar thread/kite-line often used) for tail unit control, the tension is maintained by spring tension as is full tension deflection - balanced by servo force - (spring-pull rudder and elevator - no tensioning problems or slop can intrude)

I think they're making a mistake with the split rudders in the way they have them designed. They really need to follow each other at least somewhat past centerline for the first third of their travel before splitting, with canard aircraft a little misalignment doesn't come with a drag penalty but it certainly will with a split rudder, and especially so with conventional tractor configuration slipstream hitting the vertical. There will only be a single speed and throttle setting in which the two rudders are streamlined and together, the rest of the time one or the other will be split, meaning you'll always have a small amount of airbrake deployed. The rudder pedals should also be interconnected in their movement with airbrake function as a separate lever to actuate that simply moves two pulleys to shorten the rudder cables. This would allow standard toe brakes to be used instead of pushing the pedals to the floor and forcing the airbrakes open in order to make the toe brakes work, or having to use the dreaded piper style hand brake. You may not always want to use brakes with the airbrake deployed for whatever reason, and not being able to put any pressure on the rudder pedals during flight to avoid deploying the airbrake is going to suck.

I was going to mention the drag. If you need to fly with a trim, you'd be flying with a parasitic drag. Anyway, yours went well beyond that!

They didn't have carbon fiber back in WW2. But it is a good idea if they need to.

@@LawyerPapa Ouhhh thats a solid concern.

Does a control lockout not have its own safety challenges?

You wouldn't want to lock out the rudders during takeoff, climb, or any other phase of flight since they are required for directional control.

@@DarkAeroInc only lock out the split rudder functionality. When locked, it should behave as a conventional single rudder

The ability to flip a switch to convert the rudder(s) into a single control surface would inherently be safer. (If this function is actually desired) Failures to the pins/flanges shouldn't lead to any particular dangers.

@@codeforge3301 This is what I meant to convey. Thanks.

ngl, yeranidiot see my comment above

edit: I checked my plans and the Cozy definitely has a shorter rudder moment arm than a comparable 172, previous comment deleted. oops!

The LongEZ and Cozy both place the rudder aft of the Center of Gravity. Rudder deflection yaws the aircraft in the conventional sense. Yaw control also benefits from some increased drag located far outboard. But the drag increment is minuscule compared to lift increment from a deflected flap. This is self evident in all flapped airfoil wind tunnel measurements.

Mmm ok

I agree with you. Rutan design is based on drag. In conventional control surfaces it’s the back side of the control surface that moves the airframe. It’s a wing you might say creating lift. Left rudder input means the right side of the vertical fin and right side skin of the rudder making a positive airfoil moving the tail in the left direction. I question if this will work well. I’m not an engineer but have been designing and building model aircraft all of my life for 50 years or so. Have studied design for decades. I guess we will know one day. Great project!!!

It looks like it shifts the air flow point of indecision on the leading edge so that more air will flow over the clean side and move with higher speed giving more lift. Will it be _efficient_ and forceful enough for fighting *repeating* turbulent air gust rapid wing rises or more importantly immediate effective and powerful spin recovery? Imagine an inadvertent spin at aft C.O.G. with those pretty, narrow wings.

Very good point.

How is ice going to get inside an aft-facing gap, when it is closed together for the entire duration of the flight?

Seems so to me too. What say you guys?

Speed break is cool, also wondering why both rudder halfs don't both go left/right?

The rudder deflection to trim the aircraft in climb or during normal maneuvers is small. The drag of the split rudder isn't much different than a conventional rudder for small deflection angles.

@@DarkAeroInc Thanks for the reply! So loving the epic engineering quality of this project ❤️❤️❤️

@@DarkAeroInc Since the rudders are the speed brake, can you turn on the ground and speed brake at the same time like a short-field landing?

it's much easier to do pressurized with a round cross section like a balloon. This plane is more boxy. It's not impossible but flat parts need very high strength and the canopy edge and latching mechanisms have to be very strong as well. The 'glass' would be thicker too. Or would have less glass, more or a hard top with pillars like a car, maybe. No pressurized GA plane has been done with a clear canopy afaik but not impossible. Fighter planes have it.

I don't get this either. The VariEze uses the split rudder to add a little extra pro-yaw drag out at the tips as well as the normal yaw moment, but I can't see the advantage of this on DarkAero because you're adding extra drag down the centre-line.

We are a long ways from requiring hydraulically boosted controls, which are mainly found on much larger aircraft. Even on large aircraft there are still tricks like servo tabs that enable manual controls with acceptable control forces.