California-based aviation start-up JetZero is developing the Z4, a radically different aircraft that abandons the familiar tube-shaped body used by today's passenger jets. Instead, the aircraft uses a "blended wing body" design, in which the wings and main body merge to create a wide, stingray-like shape. The company hopes the unusual design will eventually carry up to 250 passengers and travel as far as 5,000 nautical miles.
Inside the windowless cabin
Passengers could notice an even bigger difference once they step inside. The wider and lower cabin is expected to be divided into separate areas, with larger seats and individual overhead luggage space for travellers. Most of the aircraft would have no traditional windows. Instead, high-resolution screens would be used to show passengers displays or views from outside, although a small number of real windows could remain towards the front.
The design is intended to reduce weight and improve structural efficiency by removing windows from most of the aircraft.
Fuel savings and airline backing
The biggest potential benefit, however, could be the amount of fuel the Z4 uses. Its engines are positioned towards the rear, while the aircraft's shape is designed to improve airflow and reduce aerodynamic drag. JetZero claims the blended-wing design could cut fuel consumption by 50% compared with conventional aircraft, even when using the same engines.
Founder Mark Page said: "The blended wing is 50% more efficient. It uses half the fuel, makes half the carbon dioxide compared to a tube-and-wing aircraft, frankly, even with the same engines." He added: "Fuel is the largest line item on an airline's profit and loss statement. A JetZero blended wing cuts that line item in half. That's not just a competitive advantage; in the future, it'll be survival."
The project has attracted interest from some big airlines. The company is said to have backing from around 20 airlines, including Delta and Alaska Airlines, while United Airlines has previously announced plans that could see it buy up to 200 aircraft if performance requirements are met. Andrew Chang, a managing director at United Airlines, said: "We believe [JetZero] is a game changer; this is a different way to reinvent aviation."
Timeline and cost
Travellers will have to wait a while before they can board one. The Z4's maiden flight is currently scheduled for 2027, with the company hoping to begin commercial operations in the early 2030s. Smaller test aircraft have already completed more than 30 flights, according to JetZero.
JetZero also reached an agreement with the US Export-Import Bank in July 2026 over potential financing of up to $3 billion for a factory in North Carolina. Estimates put the potential cost of each aircraft at between £100 million and £200 million.
