RE:RE:Martel shrugs off the competition, saying it falls short...Ecojet, which is blended wing design can reduce aerodynamic drag by 30%. But that's aerodynamic drag, and you still need to factor in extra structural weight due to the design.
Flight characteristics of that design.is a big unknown. You need alot of testing to see how this design behaves in each flight parameters and then design fly by wire computer to control it.
Lots of R&D, which means lots of money to be spent to mature this technology.
This technology is not cost effective right now.
Engine efficiency and technology has been and will always be the driver. In this industry the airframers wait and see what new engine tech is out so they design their airplanes around the engine. Airframer aerodynamic drag and weigh reduction doesn't come close to what new efficient engine brings in.