Бескрылая схема самолёта: история и перспективы

Aircraft design with no clear divide between fuselage and wing

A blended wing body (BWB), also known as blended body, hybrid wing body (HWB) or a lifting aerofoil fuselage, is a fixed wing aircraft having no clear dividing line between the wings and the main body of the craft. This contrasts with a flying wing, which has no distinct fuselage, and a lifting body, which has no distinct wings. A BWB design may or may not be tailless. The main advantage of the BWB is to reduce wetted area and the accompanying form drag associated with a conventional wing body junction. It may also be given a wide airfoil shaped body, allowing the entire craft to generate lift and thus reducing the size and drag of the wings. The BWB configuration is used for both aircraft and underwater gliders.

In the early 1920s Nicolas Woyevodsky developed a theory of the BWB and, following wind tunnel tests, the Westland Dreadnought was built. It stalled on its first flight in 1924, severely injuring the pilot, and the project was cancelled. The idea was proposed again in the early 1940s for a Miles M.26 airliner project and the Miles M.30 "X Minor" research prototype was built to investigate it. The McDonnell XP 67 prototype interceptor also flew in 1944 but did not meet expectations. The 1944 Burnelli CBY 3 Loadmaster was a blended wing design intended for Canadian bush operations. NASA and McDonnell Douglas returned to the concept in the 1990s with an artificially stabilized 17 feet (5 m) model (6% scale) called BWB 17, built by Stanford University, which was flown in 1997 and showed good handling qualities. From 2000 NASA went on to develop a remotely controlled research model with a 21 feet (6 m) wingspan. NASA has also jointly explored BWB designs for the Boeing X 48 unmanned aerial vehicle. Studies suggested that a BWB airliner carrying from 450 to 800 passengers could achieve fuel savings of over 20 percent. The N3 X NASA concept uses a number of superconducting electric motors to drive the distributed fans to lower the fuel burn, emissions, and noise. The power to drive these electric fans is generated by two wingtip mounted gas turbine driven superconducting electric generators. This idea for a possible future aircraft is called a "hybrid wing body" or sometimes a blended wing body. In this design, the wing blends seamlessly into the body of the aircraft, which makes it extremely aerodynamic and holds great promise for dramatic reductions in fuel consumption, noise and emissions. NASA develops concepts like these to test in computer simulations and as models in wind tunnels to prove whether the possible benefits would actually occur.

In 2020, Airbus presented a BWB concept as part of its ZEROe initiative and demonstrated a small scale aircraft. In 2022, Bombardier announced its EcoJet project. In 2023, California startup JetZero announced its Z5 project, designed to carry 250 passengers, targeting the New Midmarket Airplane category, expecting to use existing CFM International LEAP or Pratt & Whitney PW1000G engines. In August 2023, the U. S. Air Force announced a $235 million contract awarded over a four year period to JetZero, culminating in first flight of the full scale demonstrator by the first quarter of 2027. The goal of the contract is to demonstrate the capabilities of BWB technology, giving the Department of Defense and commercial industry more options for their future air platforms. Following this development, JetZero has received FAA clearance for test flights of its Pathfinder, a 'blended wing' demonstrator plane designed to significantly reduce drag and fuel consumption. This innovative design could potentially lower emissions by 50%. Scheduled for full scale development by 2030, JetZero plans to create variants for passengers, cargo, and military use. The project faces challenges in certification and integration with current airport infrastructures.

The wide interior spaces created by the blending pose novel structural challenges. NASA has been studying foam clad stitched fabric carbon fiber composite skinning to create uninterrupted cabin space. The BWB form minimizes the total wetted area – the surface area of the aircraft skin, thus reducing skin drag to a minimum. It also creates a thickening of the wing root area, allowing a more efficient structure and reduced weight compared to a conventional craft. NASA also plans to integrate Ultra High Bypass (UHB) ratio jet engines with the hybrid wing body. A conventional tubular fuselage carries 12–13% of the total lift compared to 31–43% carried by the centerbody in a BWB, where an intermediate lifting fuselage configuration better suited to narrowbody sized airliners would carry 25–32% for a 6.1–8.2% increase in fuel efficiency.

A concept photo of a blended wing body commercial aircraft appeared in the November 2003 issue of Popular Science magazine. Artists Neill Blomkamp and Simon van de Lagemaat from The Embassy Visual Effects created the photo for the magazine using computer graphics software to depict the future of aviation and air travel. In 2006 the image was used in an email hoax claiming that Boeing had developed a 1000 passenger jetliner (the "Boeing 797") with a "radical Blended Wing design" and Boeing refuted the claim.