Hypersonic Vehicle Race: SR-72, Invictus, and China's Tengyun

July 25, 2026

Hypersonic vehicles (typically referring to aircraft exceeding Mach 5) are expanding from military applications to commercial space access. In 2025-2026, progress was made on the US Lockheed Martin SR-72, European Space Agency's Invictus, and China's Aviation Industry Corporation Tengyun project, marking a new stage in the global hypersonic competition.

I. US SR-72: The Plight of the 'Son of Blackbird'

Built by Lockheed Martin's Skunk Works, the SR-72, nicknamed 'Son of Blackbird,' is the successor to the SR-71 Blackbird reconnaissance aircraft. Designed for Mach 6 flight, it uses a turbine-based combined cycle (TBCC) engine that integrates turbojet, ramjet, and scramjet propulsion into a single system. Originally, the SR-72 was scheduled to make its demonstrator first flight in 2025, but as of July 2026 the project is still in the technical research phase, with the TBCC engine encountering difficult technical bottlenecks during bench testing.

II. Europe's Invictus: Continuation of SABRE Technology

In July 2025, the European Space Agency (ESA), together with the UK's Frazer-Nash, officially launched the Invictus project, aiming to develop a Mach 5 reusable hypersonic test platform. The project is based on the SABRE (Synergetic Air-Breathing Rocket Engine) technology heritage of the UK's Reaction Engines—the precooler technology can cool ultra-high temperature airflow to ambient temperature within milliseconds, allowing air-breathing engines to work normally at hypersonic speeds. Invictus uses a hydrogen-fueled air-breathing propulsion system, with a first flight planned for 2031.

III. China's Tengyun: 8,100 km/h Global Express

In October 2025, China's Aviation Industry Corporation (AVIC) unveiled the Tengyun hypersonic vehicle, designed for a speed of 8,100 km/h (approximately Mach 6.7), which theoretically could circumnavigate the globe in 7 hours. Tengyun is positioned not only as a military platform but also as a revolutionary vehicle for commercial space tourism and global rapid transportation. Over 90% of its main structure uses 3D printing technology, and it is equipped with a liquid metal cooling system to withstand temperatures exceeding 2,000°C.

• Design speed: 8,100 km/h (~Mach 6.7)
• Time to circle Earth: ~7 hours
• Structural material: 90% 3D-printed titanium alloy
• Cooling system: Liquid metal circulation
• Application scenarios: Military reconnaissance, commercial space tourism, global rapid transportation
• First flight target: 2028

IV. Three-Country Technology Path Comparison

V. Technical Challenges & Strategic Significance

The core technical challenges of hypersonic vehicles include: thermal protection (surface temperatures exceeding 2,000°C), propulsion systems (multi-mode engine switching), communication blackout (plasma shielding), and structural fatigue. The three countries have chosen different technical paths to address these challenges. The US has encountered difficulties with the TBCC combined cycle engine, Europe has chosen a more pragmatic precooler approach, and China has made breakthroughs in 3D printing and liquid metal cooling. Hypersonic technology not only has strategic value in the military domain, but also has broad prospects in commercial space—future hypersonic airliners could reduce global travel time to 1-2 hours.