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O-4U Darner

The O-4U Darner: Maybe actually use it for something!

For the time being a custom edit bench or mission is required to spawn as it is ever-so-slightly to wide for hangars. Might try to do some wing folding or something to get around that, but I'm going out of town for a bit.

Description:
The O-4U Darner is a novel quad-wing dragonfly configuration ornithopter built with the objective of attaining practical VTOL flight while minimizing shake and maximizing performance. By the numbers, O-4U is drastically superior to its predecessors, offering a virtually shakeless* ride in horizontal flight, minimally-shaken ride in vertical flight, and speeds approaching twice that of its older siblings. You'll also find it is far more domestic in flight, and enjoys the disregard for aerodynamic concerns that most conventional stormworks aircraft do. No need to worry about adverse yaw or stalling here. I'll always love the Mariposa for the nuance of flying it, but if you want something that just flies and flies easy, here you go. You can even shut the doors and use it as a submarine! It'll dive in and out of the water like some kind of horrifying lovecraftian dolphin!

*Stormworks' recent physics optimization updates appear to have decreased physics timestep resolution and introduced some joint slop. This ornithopter is still very low-shake as they go, but no longer perfect. I'm working on new reduction techniques to deal with the physics downgrade in newer projects.

Stuff for nerds:
- Specifics -
The biggest shifts in design here are the addition of an extra pair of wings, the addition of leading edge control surfaces, and VTOL/Horizontal control mixing. The addition of another wing set serves to balance forces along the longitudinal axis. In a two-set ornithopter, the wings constantly produce forward and rearward torque that can only be reduced by bringing them as closely together as possible. In this design we outright cancel that torque rather than trying to minimize it by cross-controlling each wing set with an opposing one. This is how we get close to zero shake, and also provides for stable VTOL behavior through the same mechanism. VTOL is accomplished by changing the behavior of the leading and trailing edge control surfaces so that, rather than behaving as a single unit, they instead form chevrons on the upstroke (low drag) and flatten out on the downstroke (high drag), producing net positive thrust. Control in VTOL mode is obtained by regulating the degree of this chevron effect on individual wings, or reversing the leading or trailing edge in the case of yaw. If you want to see how it works, I recommend wiring a very low constant value to the throttle input and just playing with the controls in VTOL mode so you can watch what it does.

Like my other ornithopters, this is a no-cheating, no-XML edits ornithopter, though I do intend to experiment with XML-edited hinges on other vehicles in the future.

Features in this version:
-110/117 knot cruise speed, depending on blade angle
-Stable Vertical Takeoff and Landing
-12 knot VTOL strafe speed
-200 km Range providing enough current for vertical takeoff on arrival
-300+ km Range if a vertical takeoff is not required after landing
-~3000kg useful load
-Very responsive controls
-High inherent stability
-Convenient avionics
-Dual-Axis GPS autopilot, plus autohover (engaged on arrival to a waypoint)
-Full interior

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Operation:
At this point you can fly it like most anything else in stormworks. No special instructions.