Designs

[chasgf]

I am knew to the forum but have been thinking about ....thinking about expermental plane design, has / are people looking at a conard style, larger than a Velocity but way smaller than the Avanti ll ? perhaps 6 seats in a club design, twin ?? Thanks !!
Charlie

[Hal Bryan]

Hi Charlie -

Welcome to the forum!

I know you said "larger than a Velocity", but, just in case... have you seen the V-twin?

http://www.velocityaircraft.com/airplane-models-vtwin%20-%20updates.html

(http://www.velocityaircraft.com/airplane-models-vtwin%20-%20updates.html)I'm guessing you've already come across it, but, as I said, just in case. I had a very brief look at it at Sun 'n Fun - I'm hoping we'll see it here in Oshkosh this summer.

Regards -

Hal

[steveinindy]

has / are people looking at a conard style, larger than a Velocity but way smaller than the Avanti ll ? perhaps 6 seats in a club design, twin ?? Thanks !!

I know of someone in southern Indiana who is working on a design for himself, with no intention of selling the plans or a kit, that is something like what you're talking about. The reason for the "gap" between the Velocity series and the Avanti is largely because that niche is already well filled by traditional aircraft designs and the folks with the money to build something in that range tend to just buy a new or used Seneca, Baron or one of the other existing aircraft that are readily available. Less fuss, easier to insure and you get to fly straight away as opposed to spending three, four, five or ten years building something. Also, I've read and been told that designing a canard is more complicated than designing a traditional aircraft configuration. I have no direct experience but perhaps one of the aerospace engineers or aerodynamicists on the list can chime in and correct me if I'm wrong on this.

[chasgf]

I did not know about the V-Twin !! kinda exactly what I was pondering! Thanks !!

[steveinindy]

Hi Charlie -

Welcome to the forum!

I know you said "larger than a Velocity", but, just in case... have you seen the V-twin?

http://www.velocityaircraft.com/airplane-models-vtwin - updates.html

(http://www.velocityaircraft.com/airplane-models-vtwin - updates.html)I'm guessing you've already come across it, but, as I said, just in case. I had a very brief look at it at Sun 'n Fun - I'm hoping we'll see it here in Oshkosh this summer.

Regards -

Hal

Hal, thanks for sharing that. It's a pretty airplane and I can't wait to see it in person. Now if you'll pardon me, I'm going to go wipe the drool off my chin. ;)

[Hal Bryan]

I did not know about the V-Twin !! kinda exactly what I was pondering! Thanks !!

Great - glad to have been able to point it out!


Hal, thanks for sharing that. It's a pretty airplane and I can't wait to see it in person.

I wish I'd had more time with it at SnF - it really is striking, sort of a baby Avanti or Junior Starship, depending on your preference. :)

[steveinindy]

Great - glad to have been able to point it out! I wish I'd had more time with it at SnF - it really is striking, sort of a baby Avanti or Junior Starship, depending on your preference. :) Either and/or both is any acceptable response right? ;),,

[Eric Witherspoon]

One issue is the EZ / Cozy may not continue to just scale up - in particular, these don't have flaps. So the things flaps do - steeper descent angle, adding drag, lower stall speed - might become more important as the airplane gets bigger and heavier. The Avanti has flaps - but it's really a 3-surface aircraft - not canard only. The Starship, IIRC, also has flaps, but the canard articulates to varying positions to compensate. I believe the design for such systems, and their reliable duplication and rigging would be beyond the resources of smaller companies and individual builders - in short, without some sort of flap system, the scaling up of the configuration starts to be limited by runway length. It may be possible to design/build one with a 6-seat cabin + 2 pilots, but flying from 12500' runway to 12500' runway is going to limit the utility.Then again, this may be exactly the technological development that some company is working on right now that will bring such an aircraft to the market.

[steveinindy]

but flying from 12500' runway to 12500' runway is going to limit the utility.

Seeing as how (within reasonable margins of density altitude, etc) not even jumbos normally eat up that sort of distance, it's going to be hard to botch a traditional configuration (never flown or designed a canard so I'm going with what I know here) six-seat GA design (unless you're going for obscene fuel load, etc) enough to require operation out of a field more than 6000 feet and that's with a pretty good chance of not overrunning the end if you have to abort instead of the "let's say hello to Mr. Airport Perimeter Fence" approach. ;)

For reference, a 286892 KG B777 can do a run to V1, rejected takeoff and come to a complete stop in 10,215 feet (accelerate-stop distance per one of the technical manuals).

[uavmx]

interesting about the Vtwin, but it doesn't much much bigger? Looks like they just added a tail and two engines to the normal velocity? Makes me wonder how they got the CG to come forwards after adding all that rear weight? Did they shift the wing mounting aft? Extend the nose?

Pretty sweet design, but hopefully they added a bunch more space for all the extra cost involved.


Also, with those wheels now DIRECTLY infront of the props....better have some strong props and you're going to be doing a lot of blending or fod'ing out of props.....

[Eric Witherspoon]

For reference, a 286892 KG B777 can do a run to V1, rejected takeoff and come to a complete stop in 10,215 feet (accelerate-stop distance per one of the technical manuals).

Impressive what you can do with multi-disk antilock-equipped brakes, a willingness to waste a set of tires, the capability to direct a couple hundred thousand pounds of thrust out the front of the nacelles, leading edge slats, spoilers, and a highly experienced professional test pilot at the controls well versed in what's about to happen in a brand-new airplane on a clean, dry runway on a no-wind day...
:eek: I don't think I'd like to have to fly like that every day, though. Tires, brakes, and underwear start to add up...

You can do your own research, but a quick look at the Cozy website showed that it has a gross weight 1.78x my airplane, and a takeoff roll roughly 4x longer at that weight. So though canards are "compromised" in the direction of speed, low drag, and endurance, takeoff and landing roll seems to have ended up on the other side of that compromise.

Interesting to note from the Wikipedia entry on the Starship - "a traditionally located vertical tail would have transmitted propeller noise into the airframe. In its place, directional stability and control is provided by rudders mounted in the winglets at the tips of the wings." And given the few numbers thrown around on this thread - a 6- to 8-seat-sized airplane - the Starship had 1030 lbs non-fuel payload & 6 seats. Just to give you an idea of "how big" you need to go. There really isn't much "in between" size between a 4-seat Cozy or this twin engined Velocity and the Starship.

Though I did hear that since the Starship was the first all-composite non-military airframe that the FAA certified, it did get several thousand pounds of unnecessary "structural reinforcements" to meet what the FAA thought was necessary. Maybe now, with much more knowledge and experience, all that "structure" could be swapped out for payload. In which case, there really would be a lot of design space "in between" the Vtwin and the Starship (especially if it's not certified).