In Flight adjustable wing on Scrappy

[ColdFusion]

It looks like scrappy is on the edge of awesomeness with an in-flight adjustable cord wing.


Several years ago a team in Brazil built an adjustable camber wing seeking the same outcome, lower lows and higher highs. Simple concept, worked with REM and a full spar inflatable bladders. Their challenge was not STOL, it was getting rotation and landing V’s lower.


An inflight adjustable cord is a super fun concept. Looking forward to see the progress. Interested to see if Patey copies the Brazil adjustable in flight wing design or comes out with something new.

At the end of the day, the future winners of these stol things will be dominated by hi-torq high-burst E-Drivers .

[Shadowrider]

"Never been done before" quite the claim, so I am interested to see what he tries!

[jrevens]

...

At the end of the day, the future winners of these stol things will be dominated by hi-torq high-burst E-Drivers .

Hard to see how they could do much better than Steve Henry does right now.

[Shadowrider]

Agreed! Power to weight, especially when the weight is low.

[ColdFusion]

For winning open stol comps I think Electric drives are the future on the podium.


There are many too many benefits to ignore. Yea, the battery is heavy but you only need a 3 minute burst, and you can carry the motor around in a kids backpack. The new solid state power blocks are a game changer...
1 - Super lightweight, less mass means faster stopping with smaller brakes.
2 - Instant off prop - with E-Power you can shut it off on short final and use the prop as drag instead of static thrust at gas idle.
3 - Instant on - Once stopped, hit the throttle for turn around and enjoy catapult like instant full RPM flash bang plaid thrust.


The only person I would be worried about on stol day is Steve Henry in 44 with an E-Drive.


It is going to fun to watch this play out.


Observations...
1 - You are not going to beat Steve much if any on take off.
2 - It will also be tough to beat Steve landing. This means the straightaway is where the delta D is had, and all that built up speed will be in play but by default so will mass and momentum - Patey has ALOT of mass hanging up front (are they allowing reverse pitch in the rules - if so my bet is still on lightweight E-Drives,) but reverse thrust on scrappy could present a big problem for 44, but Patey will still have some roll out. Patey may have a trick up his sleeve with near zero ground speed landing, but the big Berringers indicate ground roll. Maybe nascar air drag hinged doors are hiding.


With Patey ground support being unlimited, I am surprised he did not consider a cruise wing for cross country and then have a completion wing for Reno ferried with trailer.


The flight adjustable high lift wing will get him going slow, but that’s a lot of mass to slow down in just seconds. A lot of changing air dynamics are in play on that wing, it will take time to deploy when it is needed and it will take time for the new shape to start flowing and be fully acted upon and then you land and need to flash dump the lift (retract) and get stopped.


The longer the distance to LZ the greater benefit higher speed will play. Keep it close and you keep it pure - $75K beating $1 million rigs. Every inch you add to the airborne run the more the winners will be defined by money vrs skill.


On another note, I have been watching the Burt Rutan interviews on YouTube. Wow, that guy is so passionate. I am blown away at how many airplanes he built and the endless innovation he brought to the entire aviation community including N328K and voyager. In one of the interviews he stated how very disappointed he was with stagnation in the industry - he basically called out other kit builders for not improving their designs each year.


I wonder what the performance specs would look like with a Rutan Bushy. I wonder about what the KF8 will look like.


Grab your popcorn, it is going to be a very fun show.


A final note... a motor is electric, an engine is fuel powered.

[Rodney]

I just hope he is careful. I worry if he is pushing it too far. He's come awfully close several times to buying the farm.
He is a brilliant individual, no doubt.

[Eric Page]

...reverse thrust on scrappy could present a big problem for 44, but Patey will still have some roll out.
No reverse as long as he's using that enormous paddle-blade airboat prop. It wouldn't surprise me to see him hire Hamilton-Standard or MT to build a custom reversible prop governor, but he's put so much effort into precise CG location that I don't think he'd be willing to suffer that much weight that far forward. If there's one thing predictable about Mike's builds, it's the unpredictability.

Speaking of that airboat prop, I'll be very interested to see what kind of performance he gets from it. I'm not very familiar with airboats, but I can't believe they can reach speeds anywhere near what Scrappy could produce. I'm sure his takeoffs will be eye watering, but I'll bet his cruise speeds won't be very impressive given the horsepower involved. Says the guy with zero engineering background...

[Utah-Jay]

As stated previously Steve Henry is going to be very tough to beat mainly because he leaves very little meat on the bone, i.e. his distances are so short that there is not much room to beat him. Scrappy is gonna be very heavy, especially compared to YeeHaw.

Mike’s builds are fun to watch, but Steve is out practicing while Mike is building.

But it will be fun to watch Scrappy fly

[Shadowrider]

I agree with Jay. Only way I see to beat Steve is more HP “AND” less weight. I don’t see electric as a viable option right now. Weight of batteries is to heavy. Steve’s power to weight is unmatched. Plus 400hp out of a apex is not uncommon, but I guess it’s not needed because no one can touch his takeoffs. Steve can already takeoff brakes locked, so added torque of a electric is not needed IMO. You would just be adding weight. Only contenders I see as a worthy opponent is Jason Busat who is putting the same engine in. Of course I bet Jason is going to really push the engine. Jason will have more HP but will have more weight. Should be good match. Of course we are talking STOl and not stol drags. Stol drags is a different story and what they are going for I bet.

[109JB]

He isn't talking about it in terms of "beating" anybody in competitions, but rather to be able to get into the backcountry spots he wants to and to be able to cruise at a better clip.

[alexM]

Waaaaaay back in high school I wanted to be an aeronautical engineer so I read everything I could put my hands on. One of the books (remember those?) "Design for Flying" was written by David Thurston. In that book he stated that almost without exception the ratio of stall to top speed will not exceed 4:1.

So for a 50mph stall you get a 200mph top end. What do you know, there's a Van's RV right there. Over the years I've seen published numbers for planes and regardless of what the design goals were, Thurston's ratio has proven correct.

To exceed that ratio you need some real freak show geometry - typically heavily cambering a wing just like an airliner does with leading edges that move forward and down in conjunction with flaps at the trailing edge. You might even need to reflex the trailing edge at cruise. Molt Taylor's Mini Imp did that and he didn't create the idea.

I'm sure Patey will come up with something cool. I've got his video on right now.

As for electric
We're still a long ways from electric planes threatening the practicality of our dinosaur powered planes. BUT I grew up around r/c planes and remember when electric was a pipe dream. I was building and flying r/c in their early days and stuck with it until I actually preferred electric over nitro. I'm talking insane performance, clean, quiet and flew so long you got tired of watching them.

If I wanted to go to Valdez and make a showing I would find whoever is making the plane most of us know as the Kitfox Lite. Last time I looked them up they offered a titanium fuselage option. I would leave off everything not absolutely required for flight (covering only the wings and tail surfaces). And I would go electric.

While the weight of the batteries to make cross country flight practical are elusive, for a competition plane that only needs to fly for a few minutes that power could easily be achieved with a total power package that would compete with a two stroke.

[Utah-Jay]

He isn't talking about it in terms of "beating" anybody in competitions, but rather to be able to get into the backcountry spots he wants to and to be able to cruise at a better clip.

Just to be clear, he was big into STOL Drag when he had Draco. I think you may want to rethink the above. But my wife says I am wrong often