Abstract: Wing tip vortices are evident from airliner vapor trails, and helicopter blade slap. Elliptically loaded high aspect ratio tapered wings have minimum induced drag but cannot eliminate it. Different methods are disclosed herein, for upper and lower surface boundary layers to cancel their opposing vorticity upon shedding from the trailing edge, thereby eliminating wake vorticty, induced drag and associated noise. This requires wing-rotor-propeller or fan blades with a platform designed for uniform bound circulation and with boundary layer control near the tip. In addition this requires special techniques to counter span-wise pressure gradients, such as tip circulation control blowing or an upwind small propeller or wind turbine on each tip. These techniques can eliminate wake vorticity with its induced drag, noise, flying on the backside of the power curve and the option for asymmetric loading by pneumatic means to eliminate need for cyclic pitch control or conventional ailerons.

Abstract: The herein disclosed IC engine relies on air injection for ignition instead of Otto cycle spark or Diesel cycle fuel injection. One or more adjacent cylinders are connected by a valve, which is opened near the end of their compression strokes so that high-pressure air can inject into the cylinder containing the air fuel mixture, and induce detonation ignition at top dead center. During expansion the cylinder-connecting valve remains open and provides equal pressure on both cylinders, which is substantially higher than possible in Otto cycle. Constant volume heat addition makes this engine also more efficient than Diesel cycle. The absence of spark ignition or high pressure fuel injectors make this engine more economical, more reliable, and scalable down to very small size unlike Diesel fuel injectors which cannot meter small quantities and eliminate the Diesel cold starting problem. Engine can serve as reactor for generating high temperature hydrogen to power high temperature fuel cells.