In February 2024, a drone equipped with a newly developed rocket engine successfully approached the speed of sound, reaching over 680 miles per hour. This marked the inaugural test of Venus Aerospace’s rotating detonation rocket engine (RDRE). If successful, the company plans to develop a hypersonic commercial airliner called “The Stargazer.” With a top speed of 4,600 mph, The Stargazer would significantly surpass the hypersonic threshold of five times the speed of sound (approximately 3,836 mph).

Hypersonic flights are objects flying at least five times faster than the speed of sound.

Texas-based Venus Aerospace is working on making hypersonic commercial flights a reality. Its proposed airliner, The Stargazer, can disrupt the aviation industry by cutting the travel time of long-haul flights from hours to minutes.

According to the company, The Stargazer can fly at a top speed of 4,600 mph. This is much faster than the speed flying objects need to become hypersonic, which is five times the speed of sound, about 3,836 mph.

The aircraft can cruise for 5000 miles at a sustainable speed of 3,070 mph. It will fly 110,000 feet above ground, giving passengers a view of the earth’s curvature through their windows. For comparison, modern commercial airliners typically fly at a maximum altitude of 42,000 feet.

To achieve this feat, Venus Aerospace has developed a new propulsion engine, the Venus Detonation Ramjet 2 (VDR2). While the VDR is a single unit, it combines the key technologies of a ramjet and a rotating detonation rocket engine (RDRE) to achieve hypersonic speed.

Under the rotating detonation mechanism, the fuel does not undergo a steady burn. Instead, it detonates, generating high-pressure shock waves that travel at supersonic speeds within the engine. This provides a higher efficiency and sustained thrust over traditional jet or rocket engines.

On the other hand, the ramjet compresses incoming air by using the engine’s speed as it moves forward rather than mechanical components like turbine blades. As there are no moving parts involved, it can withstand high temperatures of up to 3,860 °F, making it suitable for the extreme conditions faced by hypersonic flights.

The Stargazer will have 50% less of a carbon footprint than a Gulfstream fitted with traditional jet engines.

Venus Aerospace’s project is ambitious, to say the least. Developing hypersonic flights is a challenging and costly endeavor, and the challenges do not arise solely from a technological standpoint.

At its top speed, The Stargazer could fly the distance between London and New York in under an hour instead of the average eight hours.

But are existing airports in these two cities, and others around the world, equipped for handling hypersonic aircraft?

While Venus Aerospace is working on making the aircraft operational from 30 existing airports, the company has not clarified how it intends to handle noise pollution around airports.

Hypersonic flights produce sonic booms that can impact communities near airports. In 1973, the US banned non-military aircraft from flying over land above the speed of sound. NASA advocates a regulatory shift to base flight restrictions on noise pollution levels rather than speed. However, the current ban on non-military supersonic flights over land remains in effect.

The Stargazer must also keep in check its ecological impact. Venus Aerospace has indicated that its aircraft is designed to achieve 50% lower carbon emissions than a similarly sized Gulfstream business jet.

They are also exploring the potential to use Sustainable Aviation Fuel (SAF), a cleaner alternative to conventional jet fuel derived from renewable sources like agricultural residues, algae, or waste oils. Compared to traditional jet fuels, SAF can reduce lifecycle carbon emissions by up to 80%.