- Mon Mar 05, 2018 11:26 pm
#402530
While it's structurally very simple, aerodynamically I don't think it is. The Pou du Ceil, or Flying Flea, has a similar tandem-wing configuration. Several of the pre-WW2 models dove in because the forward wing was used for pitch control.
Pulling out of a dive at high speed, the gap between the wings decreased, which increased the airflow over the rear wing, increasing the lift on the rear wing, which pitched the aircraft more nose down. The harder the pilot pulled back, the worse the pitch down got. Apparently this didn't happen at low speeds, because people were able to fly them.
Post WW2, the pitch problem was fixed by some changes in airfoils, and, I think, using a conventional elevator on the rear wing and having the gap between wings be fixed. Then several of those crashed due to Dutch Roll. There are people building and flying them today, but the configuration is not without its issues.
I'm not saying it isn't feasible at all, but I suspect that like many unexplored corners, Here There Be Dragons.
Pulling out of a dive at high speed, the gap between the wings decreased, which increased the airflow over the rear wing, increasing the lift on the rear wing, which pitched the aircraft more nose down. The harder the pilot pulled back, the worse the pitch down got. Apparently this didn't happen at low speeds, because people were able to fly them.
Post WW2, the pitch problem was fixed by some changes in airfoils, and, I think, using a conventional elevator on the rear wing and having the gap between wings be fixed. Then several of those crashed due to Dutch Roll. There are people building and flying them today, but the configuration is not without its issues.
I'm not saying it isn't feasible at all, but I suspect that like many unexplored corners, Here There Be Dragons.