Key Points
- Supersonic flights match or slightly exceed the speed of sound, while hypersonic flights reach speeds five times faster than sound.
- Hypersonic flight is still largely experimental and theoretical, while supersonic flight is well established and has seen commercial and military use.
- Supersonic flights have a higher environmental impact due to fuel consumption and sonic booms, while hypersonic flights fly at higher altitudes and have less noise pollution on the ground.
- Supersonic aircraft like the Concorde have been retired, but commercial supersonic flight is making a comeback with the production of the Boom Overture.
- Hypersonic aircraft are still under development, but promising projects like the Stargazer aim to reach speeds of Mach 9 and could revolutionize commercial aviation in the future.
Over the years, humans have made tremendous technological strides, and supersonic flight certainly comes to mind. Back in 1903, everyone was losing their minds because the Wright Brothers managed to get a plane off the ground. Now, we’re arguing about whether we’re going faster than sound or, get this, five times faster than sound!
Simply put, if supersonic flights once seemed like something from a science fiction movie, hypersonic flights are truly out of this world (almost literally). Essentially, supersonic machines match or slightly exceed the speed of sound, while hypersonic technology reaches speeds five times faster than sound.
Now, let’s have a real chat about these two types of flights. We’ll explore their technological implications and how accessible they are to the general public.
Hypersonic vs. Supersonic: Side-by-Side Comparison
| Hypersonic | Supersonic | |
|---|---|---|
| Speed | Speeds exceed Mach 5 | Faster than the speed of sound (Mach 1) but slower than Mach 5; typically between Mach 1 and Mach 3 |
| Typical Uses | Experimental aircraft and future commercial space travel | Military aircraft and future commercial flights |
| Technological Challenges | Extremely high, many technologies are still experimental, and reliability is a significant concern | High, but largely solved for specific applications like military aircraft |
| Flight Altitude | Generally higher, often in the mesosphere (30 to 50 miles above Earth) | Generally lower, below 60,000 feet |
| Sonic Boom | Usually inaudible on the ground due to the extreme altitudes | Sonic booms are created, which can be disruptive on the ground |
| Environmental Impact | There is less noise pollution on the ground due to the high altitude. Heat and atmospheric pollution could be major issues. | Higher fuel consumption than subsonic flight, noise pollution due to sonic booms |
| Passenger Experience | Fast travel times are likely to be more intense and possibly uncomfortable due to acceleration forces and the potential for weightlessness | Quick travel times, but potential discomfort due to the sonic boom and need for high altitude |
Hypersonic vs. Supersonic: Differences Explained
The biggest difference between hypersonic and supersonic flight lies in their speeds. Supersonic aircraft have seen real-world applications and widespread use in recent decades. However, the concept of developing hypersonic vehicles is mostly still on the drawing board. This is due to the challenges associated with surpassing Mach 5 speed. It’s not just about making the tech, which is tough enough. It’s also about making it work in the real world, which is a whole new level of tricky.
Let’s break down the key differences between hypersonic and supersonic aircraft.
Technology
Although hypersonic flight has had some instances throughout history, its usage remains experimental and its discussion is largely theoretical. The challenges include designing a craft that can handle Mach 5 speeds and developing an engine powerful enough to propel it. However, there have been some major advancements.
In 2022, the U.S. Air Force successfully tested a turbojet-ramjet hybrid engine known as “Chimera.” It’s a significant achievement because it paves the way for the “Quarterhorse,” a proposed hypersonic airplane from Hermeus. In this design, a ramjet propels the theoretical Quarterhorse aircraft beyond Mach 5 by relying on high speeds to pressurize the air-fuel mixture.
In contrast, supersonic flights are well established. Although they have seen commercial use, these fast planes are primarily seen in military use. Such aircraft, like the Lockheed Martin F-35 Lightning, often utilize turbofan engines. Moreover, they boast an aerodynamic design that helps reduce air resistance to allow for higher speeds. The key feature is thin, angular wings that cut through the air.
©jgorzynik/Shutterstock.com
Applications
Supersonic flights took off (quite literally) in 1947 with the Bell X-1, an experimental plane from the USA. Since then, their use has been primarily military, though there were exceptions, like the famous Concorde that catered to commercial flyers. This model, along with other supersonic planes, was discontinued due to high production and maintenance costs, among other factors.
That said, don’t write off commercial supersonic flight just yet. The Boom Overture, a future commercial supersonic plane, starts production in 2024 and is expected to be operational by 2029.
One of the primary examples of hypersonic flight was NASA’s X-43A. During a research stint, this speedster made headlines when it clocked in at a record-breaking Mach 9.6.
Currently, hypersonic speeds are mostly used in military technology, like China’s XingKong-2 or Russia’s Avangard. These technologies are anticipated to be pivotal in the future space race.
©Senohrabek/Shutterstock.com
Environmental Implications
While supersonic and hypersonic flights represent a triumph in human innovation, they do come with considerable environmental implications. The main concern is their voracious appetite for fuel, which leads to hefty greenhouse gas emissions.
One of the biggest drawbacks of supersonic aircraft is the sonic boom caused by their engines. Researchers have been working tirelessly on different plane designs and strategies to dial down the noise, particularly in overpopulated areas.
Hypersonic technology faces the same challenges in terms of high fuel usage. Nevertheless, the sonic boom is virtually inaudible on the ground as hypersonic vehicles and devices fly at extremely high altitudes.
To address the issues of fuel consumption and pollution, technologies such as hydrogen engines and high-density electric batteries are under investigation as cleaner alternatives that could one day take flight in a greener aviation future.
Supersonic Aircraft: Here to Stay
Supersonic speed technology became a reality with the American Bell X-1 in 1947. This marvel of aviation ran on a rocket engine. It produced a 6,000-pound thrust, fueled by a mix of liquid oxygen and ethyl alcohol. A lengthy history of research, study, and manufacturing for various purposes followed this milestone.
While supersonic aviation is currently mostly used for military exploration and bombing, there have been instances of commercial supersonic aircraft. Take the Concorde, for instance. This French jet operated between 1976 and 2003 and could reach speeds of over Mach 2, close to 1,354 miles per hour. Unfortunately, it was ultimately retired due to high costs and a tragic crash in 2000.
Today, some of the most well-known military supersonic aircraft are the Northrop Grumman B-2 Spirit and the Lockheed Martin F-35 Lightning II.
These sophisticated machines represent the cutting edge of supersonic technology. They’re equipped for various military operations, from ground assaults to ensuring air dominance.
©Kletr/Shutterstock.com
Hypersonic Aircraft: Still Under Development
The field of hypersonic aviation is even more ambitious. It’s a challenging journey, but tangible applications are starting to take shape. For example, Venus Aerospace is planning to manufacture the Stargazer. This plane aims for the stars with a speed target of Mach 9 — quick enough to whisk you from Tokyo to New York in just one hour.
The secret ingredient is a rotating detonation engine that spins at 20,000 revolutions per second. Another piece of good news is that the rotating detonation burns 20% less fuel than a conventional engine, earning it a nod from the U.S. Navy. The concept is to let the plane climb almost to space, then flip the switch to rocket mode to max out its speed.
The future seems bright for the Stargazer project and similar initiatives. However, there’s still a long way to go in development and testing.
Despite the challenges, the hypersonic realm holds promise. As we push the limits, it’s likely that hypersonic speeds will gradually become a common feature of commercial aviation in the future.
Hypersonic vs. Supersonic: 5 Must-Know Facts
- Supersonic aviation can surpass the speed of sound.
- Hypersonic aviation exceeds five times the speed of sound.
- The most famous commercial supersonic aircraft in history is the Concorde.
- Although it’s still in an experimental phase, Venus Aerospace plans to use hypersonic aircraft to traverse the globe with passengers.
- The main obstacle for both supersonic and hypersonic aviation is their high fuel consumption.
Wrapping Up
When it comes to supersonic and hypersonic flights, we’re dealing with a straight-up race against the speed of sound. While supersonic aircraft can reach the sound barrier, hypersonic machines far surpass it. This also implies different sets of challenges associated with each method.
Supersonic planes aren’t a new phenomenon. Currently, they are primarily used for military operations. Nonetheless, some companies, like American Airlines, are investing in developing their own supersonic passenger aircraft.
Hypersonic aviation, on the other hand, is still largely confined to the drawing board regarding civilian use. That said, it’s not an impossible dream. There are loads of ambitious companies out there engineering their way toward this dream.
Imagine cross-continental travel in less than an hour. That’s the promise of hypersonic flight!
The image featured at the top of this post is ©Keith Tarrier/Shutterstock.com.
