New information from China confirms its scientists will be unable to deploy a hypersonic boost and glide missile by 2020 and hypersonic missiles propelled by scramjets by 2025, as estimated by U.S. intelligence.

Chinese state-owned media has reported China will test a prototype combined-cycle hypersonic engine -- one of the proposed propulsion systems for a hypersonic glide vehicle or HGV -- later this year. If successful, this test might lead to the first demonstration flight of a full-scale scramjet propulsion system by 2025.

A scramjet is a variant of a ramjet air breathing jet engine where combustion takes place in supersonic airflow. This allows the scramjet to operate efficiently at extremely high speeds.

The Chinese are already claiming this combined-cycle hypersonic engine, which is likely a Turbo Rocket Combined Cycle (TRCC) propulsion system, could be the first of its type to power either a hypersonic vehicle or the first stage of a two-stage-to-orbit spaceplane.

This announcement followed China recently making public the first known images of a scramjet test it said reached Mach 7 (8,600 km/h) and an altitude of 30 kilometers on December 2015.

"We also developed a low cost near-space science and technology flight test platform," said Lihong Chen, a Chinese Academy of Sciences professor.

"The first flight test was successfully carried out, and key issues of the scramjet were demonstrated at Mach 3.5-7 and at altitudes of 15-30 km (9-18 miles)."

These facts contradict intelligence estimates presented before the U.S. Congress in mid-2016 that China's HGV program "progressing rapidly."

At the time, a U.S. congressional commission reported China might be able to deploy the DF-ZF experimental HGV as warheads on Chinese ballistic missiles as early as 2020.

Formerly designated WU-14, the DF-ZF is a hypersonic missile delivery vehicle that's been flight-tested by the Chinese seven times from January 2014 to April 2016. Six of these tests are known to have been successful.