The Super Duper Sabre flies! I flew it for the first time today with mixed results. The short version is that it flies beautifully and will be pretty near perfect with a bit more tuning in the air. However, it inherited all the landing gear problems from the Ghost and 2 of 3 struts collapsed on a landing that was admittedly harder than it should have been. Fortunately, the required repairs are pretty minor. Here's a picture post maiden flight:
In the air, the Super Duper Sabre is surprisingly docile for being such a heavy jet with such small wings. Roll control is good at all speeds with the combined ailerons and elevon stabilators. I need to turn up the elevator rates a bit, but overall, it responded well to what I told it to do. It also slows down shockingly well with flaps - it's still a heavy plane but with the flaps down it slows down as well as many lighter EDFs. There was a weird uncommanded left roll right after takeoff, but I think it must have just been wind or me not letting go of the rudder quickly enough since it went away very quickly in flight. This is really the Reynolds number (size and speed of airplane) I designed this airfoil for, in this plane, and it shows in being much less stall-prone than any of my previous laminar flow wing designs. It's been interesting flying these more recent designs derived from my experimental planes thread since none of them (the Ghost, Rapier and now Super Duper Sabre) really feel like they're flying fast even when they clearly are. I'm guessing I got it ballpark 120-130 mph on this maiden flight with no gear doors and no attempt to optimize passes and only maybe 10 seconds of full throttle in the full flight, but that's really just based on going, wow, it's getting small quick a couple of times. Control response felt the same with full flaps at landing speed as it did at full throttle.
I'm also really very happy with the CFD trim predictions. The plane needed next to no elevator trim and had no trim change with the flaps thanks to the (fairly aggressive) elevator mix I had preprogrammed on the ground. I do want more elevator, but that's a matter of preference - it's hitting the angles of attack I predicted, I just want more ability to get it to higher angles of attack if I want to. My original tune was meant to avoid pitch up but with the 50mm version, I proved that was pretty manageable if you gave it more throw so now I want to be able to maneuver a bit more aggressively.
However, the landing gear and surrounding structure are a problem. My landing must have been harder than I thought since both wings cracked just outboard of the gear struts and one of the main struts broke off right at the retract unit. The nose gear also pulled a new trick and punched its way through the bottom of the inlet duct although the strut itself survived.
To fix this, I plan to add carbon fiber rods running through the section of the fuselage around the nose gear and the full span of the wings. I also need to look at redesigning the main gear struts, maybe with a trailing link design. After all the pain with these gear struts in the Ghost, I intentionally designed in extra space in case the gear needed to get a bit bigger in this one. Fortunately, the parts that broke are the easiest ones to fix - the wings are only a few parts each, and the nose fuselage is grand total of 3 parts so I can reprint them pretty fast. And everything unbolts so I can just remove the wings with 3 screws each and the nose fuselage with 8 screws and not need to risk damaging anything else.
