Chinese scientists have released the first images of a prototype of transformable hypersonic missile able to reach Mach 5 -6,174 km/h- and modify its configuration in mid-flight. To do it, integrates retractable wings that fold inside the fuselagereduce aerodynamic resistance and allow extreme speeds to be maintained.
On the contrary, deploying them provides greater lift and maneuverabilityfacilitating more precise turns and glides, as well as finer control of flight, according to the South China Morning Post.
This ability is considered a kind of Holy Grail in this field. In vehicles that operate at such high speeds, engineers are often forced to choose between optimizing form for speed or control, but not both.
The development is carried out by the teacher’s team Wang Pengof the National University of Defense Technology (NUDT)a leading military research institution in China. Their work, published in Acta Aeronautica et Astronautica Sinica, goes beyond theory, as demonstrated by the images and hardware-in-the-loop (HIL) tests carried out.
In these tests, the control system is connected to real sensors and components that operate in a simulator that reproduces flight conditions. The objective is to demonstrate that the platform can work in real time with physical hardware and not only in simulations.
The military implications are clear. China has already shown the hypersonic cruise missile CJ-1000which maintains that it can attack mobile targets – aircraft or ships – thousands of kilometers away. Something considered until recently impractical, given that at hypersonic speeds maneuverability is usually sacrificed in favor of speed. The concept of retractable wings aims to break that limitation.
In an operational scenario, the missile could fly at maximum speed with folded wings to quickly reach your target area and, once there, deploy them to maneuver, change course or altitude and make prediction or interception difficult. If these capabilities are confirmed, they would provide a considerable advantage in attacking high-value mobile targets, such as aircraft carriers or stealth fighters.
The technical challenges, however, are enormous. Flying above Mach 5 – the limit above which hypersonic flight is considered – exposes the vehicle at temperatures above 2,000 °Csufficient to soften metals and ionize the air. This phenomenon creates a layer of plasma around the missile that can interfere with communications, guidance and sensors.
Added to this are the enormous aerodynamic forces that make every moving surface a potential point of failure. In a design with retractable wings, each movement alters the aerodynamics and requires recalculating lift, resistance and stability in milliseconds. Actuators must operate without delays or vibrations, but On-board computers – designed to be compact and rugged – do not have the computing capacity of a supercomputer..
The team claims to have solved this complexity thanks to a algorithm which combines three elements: a high precision mathematical modeling of the behavior of each part of the aircraft, a prescribed performance control -which sets limits and response times in advance- and a control method robust so-called ‘super-twisting sliding-mode control’, designed to maintain stability even with disturbances and without generating harmful vibrations in the actuators.
Although its main motivation is military, the authors aim to possible civil applications. In theory, such a technology could reduce intercontinental flights to 1–2 hours and enable ultra-fast freight transportation between continents.