A supersonic transport (SST) or a supersonic aircraft is designed to transport passengers at speeds greater than the speed of sound. To date, the only SSTs to see regular service have been Concorde and Tupolev Tu-144.

Concorde is a British-French supersonic airliner. Concorde began scheduled flights with British Airways and Air France in January 1976. The Concorde had a top cruising speed of 2.179 km/h, or Mach 2.04, more than twice the speed of sound, allowing the aircraft to reduce the flight time between London and New York to about 3 hours. AF flew its last commercial flight on 30 May 2003, and BA retired its Concorde fleet on 24 October 2003.

One aircraft was scrapped in 1994, and another was destroyed in the Air France Flight 4590 crash shortly after taking off, with all 109 occupants and four on the ground killed 2000. And it was the end of the Concorde era.

Tupolev Tu-144, a Soviet supersonic passenger airliner designed by Tupolev, was in operation from 1968 to 1999. The Tu-144 was the world's first commercial supersonic transport aircraft, with a top speed of 2,430 km/h, Mach 2.35. The Tu-144 was bigger and faster than Concorde. Tupolev-144 crash... The incident at the 1973 Paris Air Show happened when the Tu-144 swerved to avoid a French Mirage IIIR fighter jet, which had taken off before the accident.

The flights were expensive, mainly shuttling business people and the rich and famous. Concorde was a product of the analog era when the idea of flying to London or New York for the day for an important business meeting seemed like a necessary thing. Today, in a world of remote work and video meetings, maybe for that reason, we don't need the supersonic flights. Cheaper, larger, and more efficient airliners (the Boeing 747 entered commercial service in 1970) blew Concorde out. Concorde may be gone, but that doesn't mean that supersonic passenger flights are over. The US is determined to restore supersonic air travel for all, and aerospace agencies and manufacturers are proceeding along this course. 14, 16, and more flight hours are awful.

Cutting it down to 4 will be great. SS doesn't make sense for short distances, but for trans-Pacific and Atlantic, it does. SS needs to climb to a very high altitude to make it practical. Eliminating the sonic boom and reducing costs are problems. Concorde was extremely fuel inefficient when taking off and accelerating. If those problems could be solved, a return to supersonic flight would become a definite possibility. Noise is a real problem for supersonic flight. A supersonic plane causes disturbances called 'sonic booms.' In 1970, sonic boom concerns led the United States government to ban supersonic passenger flight over land in the U.S.

Safety concerns, deafening sonic booms, high prices, and a crash in France in July 2000 spelled the end for Concorde. A future for supersonic travel relies on solving some or all of the issues Concorde faced. Endeavors by Boom Supersonic, Exosonic, Spike Aerospace, and several major airlines are putting the possibility of supersonic back in the game. American company Boom Supersonic has an ambitious goal to have supersonic airliners carrying passengers by 2029. Boom Aviation completed the production of its Overture passenger jet in the facility in Greensboro, NC. Deliveries are scheduled for 2027, supposedly.

The plane will be much improved over the Concorde in fuel efficiency and 50% longer range. In terms of gas guzzling (Boom Supersonic Overture), they plan to use up to 100% sustainable aviation fuel to reduce emissions and their carbon footprint.

Modern design methods and modern aerospace materials such as titanium and carbon fiber should allow Overture to weigh much less than Concorde, improving efficiency. An airliner called Overture can fly at Mach 1.7, and flying supersonically can drastically decrease flight times. The Boom company claims a trip from New York to Rome on Overture could take just four hours, cutting journey times to as little as half of their subsonic equivalents. Boom Supersonic XB-1 became the first civilian aircraft to fly supersonically since Concorde. The plane speed (with Mach numbers greater than 1) is faster than the speed of sound (meaning 'to break the sound barrier'). As the plane flies, it disturbs the air in front of it, and in supersonic flights, these disturbances combine to form shock waves around the vehicle.

The only manned aircraft to fly in the low hypersonic regime were the X-15 and the Space Shuttle during re-entry. The X-15 used a rocket propulsion system to achieve sustained Mach 6 flight. For Mach numbers greater than 5, the frictional heating of the airframe by the air becomes so high that very special nickel alloys are required for the structure.

With modern technological advances, supersonic passenger travel will become a reality, and the technology will build an ambitious aircraft that will be available in the foreseeable future. The hypersonic jet concept...is one of them, designed to travel at an incredible speed of 5-10 Mach. This conceptual supersonic aircraft (Paradoxal hypersonic) looks like a futuristic version of the B-2 stealth bomber. The paradoxical hypersonic jet has a flat fuselage with integrated delta wings. The Paradoxal is powered by a dual-engine system called the R4E, which delivers a two-stage journey. In the first stage, the hypersonic aircraft can accelerate to Mach 3.0 and climb to 60,000 feet using air-breathing engines. And in the second stage kicks in, introducing liquid oxygen into the propulsion system, which turns it into the rocket engine.

This will propel aircraft to Mach 5 and beyond, taking them to the edge of space. The hypersonic military jet (the fictional Darkstar jet) in the actor Tom Cruise's film Top Gun: Maverick had a top speed of Mach 10. Many scenes in the movie break numerous laws of physics. Flying at such speed and altitude would have dire consequences on the human body. The Stratolaunch aircraft is being used to test high-speed hypersonic flight research vehicles. Stratolaunch recently completed two successful test flights of its new hypersonic plane. The Talon-A2 autonomous plane flew faster than Mach 5, five times the speed of sound, before landing at the Vandenberg Space Force Base in California.

It was the first time a hypersonic test aircraft was flown in the United States since NASA left the X-15 program in 1968. Other companies in California and Georgia are also working on hypersonic engines and airframes. China, Russia, and the U.S. have been working on hypersonic aircraft for decades. Hypersonic flight is flight through the atmosphere below altitudes of about 90 km at speeds greater than Mach 5. The idea of hypersonic aviation is becoming more and more clear every year. On the civil side, hypersonic flight remains a long-term ambition, with research targeting Mach 5 passenger aircraft that could drastically reduce intercontinental travel times. China revealed a new hypersonic fighter jet that reaches the speed of light, surpassing Mach 5 and setting records in ways we could only imagine.

The Soviet hypersonic fighter MIG-15 achieved greater speed, a higher service ceiling, and heavier armament. With the creation of the 6th generation of hypersonic fighter concepts and its powerful and lethal air fighters, Russia is ready to dominate the world with its unrivaled military technology. Russia has created the ultimate weapon, the Sukhoi-57, designed with stealth technology. Northrop Grumman has successfully demonstrated GPS-independent navigation using a cutting-edge inertial measurement unit aboard its hypersonic test vehicle. The fastest jet in the world is NASA’s X-43 hypersonic experimental plane. Three of these were built in total. Thanks to its scramjet design, it was able to reach a speed of Mach 9.9, or 11,854 km/h. This is the future of air combat.

The hypersonic weapons are capable of traveling at hypersonic speed, defined as above Mach 5 (hypersonic missiles, hypersonic glide vehicles). Most supersonic military fighter aircraft are designed to fly at subsonic speeds and only to exceed the speed of sound for short periods, such as when intercepting an enemy aircraft. Supersonic military aircraft continue to be developed, focusing on enhancing speed, agility, and stealth capabilities. Programs like the U.S. Air Force’s next-generation air dominance and other international projects are focused on the requirements for the next generation of supersonic fighter jets. Key research areas include improving supersonic cruise efficiency, maneuverability at high speeds, and minimizing radar signatures. Hypersonic technologies may also be poised to revolutionize military systems by enabling vehicles that travel above Mach 5 with high maneuverability, making them nearly impossible to intercept.

Technology can be developed rapidly... The question is, do we need to go so fast?

Elon Musk debuts revolutionary hypersonic aircraft, which could be nearing the speed of light, which has sparked global shock waves. And it can use microwave energy. Concorde needed as much as eight times more fuel compared to a Boeing 747. The cost of developing, building, and testing a plane is pretty high. Development of modern jetliners runs into multiple billions of dollars, and maybe there will not be sufficient demand for a large production. Engineers take years and years of development, and a brand new one costs billions of dollars. Whether the issue of the sonic noise can be overcome remains to be seen. Prohibitively high costs are among the reasons both Soviet Union and the United States abandoned their quest for supersonic passenger flight.

The commercial aviation supersonic market is currently not a priority. But if it does ever take off again, we are more likely to see success in the business aviation market rather than with large-scale commercial planes. Of course, there is still hope that we could one day be whizzing around the world in a few hours. If the NASA project is successful and operational costs can somehow be lowered, supersonic jets can cover longer distances in a few hours. But we might have to wait a little longer. With modern technological advances, it will be interesting to see whether supersonic passenger travel once again becomes a reality or even goes mainstream. Only time will tell. The only possible way supersonic flights could return would be if someone like Elon Musk or Jeff Bezos decided to bankroll the entire project and were fine with the massive overhead costs.