Say hello to the RV-15 engineering prototype and some of the folks who designed it.
This pic about 20 minutes before the team showed the RV-15 to the OSH crowd in person.
L-R: Rob, Scott, Axel, Rian and Brian.

What We Know:
(sent to me by Van's employees)

• RV-15 Engineering Prototype (Mothership Page)  

• 12 to 18 months until we release either the wing kit or the empennage kit, hopefully by Oshkosh 2023.

• Utility category: +4.4, -2.2

• Engine: From 180 hp to 220 hp.

• Goals: 900 lbs useful load, 140 KTAS cruise

• Seats: 2+Baggage. Optimized for a mission of "2 people and a whole lot of gear". The back area could have a bench seat for two little kids or a third adult seat. Currently the capacity of the back area is 200 lbs.

• Float kit in early preliminary design stages.

• 35.5 ft span with the wingtips on the prototype.

• (re: RV-15 w/215hp vs C170 w/145hp)
  The C170 weight and the target weight for the kit RV-15 are essentially the same. We just want to do more.

• (re: Gurney flaps on elevator trailing edge)
  ...This is an engineering prototype. We had a choice of going quick or leaving the plane at home. In order to go quick, we can change the length or height of the tab. That takes hours. Or we can build a new stab which will take days. After flying the airplane, I provided the feedback that the stick force per G was too light. So we are tuning the feedback/forces. When we get the plane home, we will build a new stab with the hinge 1/8 of an inch from where it is now and the forces will be what they are now.
  The final kit will not have those on.

• Each flap is over 10 feet.

• Cabin width is 46", same as an RV-10, 4" wider than a Cessna 180.

• Trapeze ropes in cockpit:
  "The rope pull handles are test aircraft feature only, to enable emergency door jettison if needed."

• Fuel Tank:
  "The fuel tank in the cabin is only for the test airplane. Certain prototype aircraft design considerations are there to enable us to make engineering changes and adjustments (keep in mind, this is an engineering test prototype airplane), easily change configurations in weight/balance, loading, etc."

• Baggage Door:
  The kit will have one.

• 34-percent-chord ailerons (versus 25% in other RVs) in part inspired by the Helio Courier (also true of the stabilator).

• Airfoil designed with aerodynamicist Steve Smith to combine high lift with docile stall. Most STOL airplanes have high-camber airfoils (i.e. you never fully get rid of the flaps); This one does not, so drag is lower, cruise speed will be higher.

• Stiffness of landing gear shock absorbers is tunable via air pressure.

• Parallelogram four-bar linkage in tailwheel ensures constant caster angle, preventing shimmy.

• Lots of fairings still need to be added.

• For easy entry, the seat slides all the way back behind the door, and the stick has a "D shape" so most of it is under the panel; It's easy to step in between the seat and the stick.

• Cowl will be improved: Right now it's a slightly modified 14 cowl. Needs bigger openings, would probably benefit from cowl flaps.

• Its unique articulated landing gear, with shock absorbers hidden in the floor, sets it apart from its competition and predecessors. Patent pending!

• The RV-15 kit will be offered with domed-head blind rivets, the same LP4 rivets used on the RV-12, just because they allow for faster assembly and have more than the required structural capability.
  For folks who would prefer flush solid rivets, like on all other RVs, we are hoping to be able to offer the option of using AN426A4 rivets on the exterior skins. Most rivets in other RV skins are AN426AD3, where "AD" means aluminum 2117 - which is quite hard - and "3" means 3/32" diameter. This new rivet being tested is the "A4": The "A" by itself means that it's made of aluminum 1100 (pure aluminum) which is softer than conventional rivets. Lots of tests and structural analysis must be done to show that the strength and fatigue properties of AN426A4 rivets - i.e. 1/8", flush, solid, "soft" rivets - are acceptable for assembling RV-15 structure. These tests and analyses are still ongoing, but initial results are promising, and we hope to offer the option of using these soft flush solid rivets for fastening at least most of the external skins.

• I know it probably seems like worlds away from a lot of the U.S, but out here in the west, particularly here in the Pacific north west, there is a huge number of airstrips that are not particularly short (often times because of their elevation), or particular rough, but that are located in the "back country" and having an airplane that is biased more towards the capabilities of a true back country airplane can still be beneficial.
  
  The RV-15 will be capable of using the rougher / shorter back country strips, but I think the average user will be someone that doesn't regularly fly it to that extreme of its capabilities.