On the fateful day of July 25, 2000, around 4 PM, Air France flight 4590 was poised for takeoff. This flight was not your ordinary passenger journey; it was the domain of the Supersonic Concorde, an aircraft capable of traversing the skies at twice the speed of sound. To put this into perspective, it streaked through the air like a bullet fired from a gun. Whereas typical passenger flights on conventional planes took a leisurely 8 hours to make the voyage from Paris to New York, the Supersonic Concorde slashed that time to a mere 3.5 hours. But there was an unmistakable distinction about this flight—it was an opulent experience, reserved for the affluent. Traveling on the Concorde was the epitome of luxury, far beyond the reach of the average person, as a round-trip ticket between Paris and New York would set you back $12,000, and this was 22 years ago. Considering inflation, that price tag would equate to roughly $20,000 in today’s currency. This ticket amounted to over ₹1.5 million, and as the clock ticked to 4:40 PM, the aircraft was ready to embark on its journey.
As the plane began its acceleration along the runway, an unsettling discovery was made by the Air Traffic Controller—a fire had ignited beneath the aircraft. An alert was promptly relayed to the pilot, but it was a case of too little, too late. The plane was already hurtling down the runway at a considerable speed, rendering an abortive takeoff impossible. The pilot, with the grim realization that there was no turning back, radioed the controller to convey that the plane could not be stopped. In mere seconds, the aircraft soared into the sky, the fire escalating to an uncontrollable blaze. The pilots made desperate attempts to regain control, disengaging certain engines, but the aircraft was unable to achieve the required velocity. Onlookers on the highway adjacent to the airport witnessed the horrifying spectacle unfolding before their eyes. In a matter of minutes, the situation deteriorated to a point where the pilots lost all command over the aircraft. Tragically, the Concorde crashed into a hotel located 15 kilometers from Paris. This harrowing accident claimed the lives of all 100 passengers aboard, as well as the lives of the 9 crew members. The devastating outcome of the crash reverberated around the globe, as the world grappled with the loss.
“The world’s most prestigious aircraft crashes. More than 100 people are dead.” The Concorde crash sent shockwaves throughout the world, leaving people incredulous. How could this happen? The Concorde was the epitome of aviation prestige—the crème de la crème of aircraft, renowned for its Supersonic capabilities. However, the crash of this one aircraft irrevocably transformed the trajectory of Supersonic aviation.
Breaking the Sound Barrier
My friends, the term ‘supersonic’ is inextricably linked with sound, specifically the speed of sound. Ordinarily, the speed of sound at sea level hovers at approximately 1,236 kilometers per hour, with some minor fluctuations depending on air temperature. The classification of aircraft speed falls into four broad categories: Subsonic for speeds lower than the speed of sound, Transonic for speeds around the speed of sound, Supersonic for speeds exceeding the speed of sound, and Hypersonic for speeds surpassing five times the speed of sound. It is important to note that the unit of measure for this speed is known as the Mach number, which signifies the ratio between an aircraft’s speed and the speed of sound.
The typical passenger aircraft in which we embark travel at speeds of approximately 900 kilometers per hour, classifying them as Subsonic. The Concorde, which I reference in the past tense since it is no longer in operation (and I shall delve into the reasons later in this narrative), boasted speeds of around 2,160 kilometers per hour, placing it in the Supersonic realm with a Mach number close to 2.0. For a captivating tidbit of information, the current title-holder for the world’s fastest aircraft is the Lockheed SR 71 Blackbird, with a staggering Mach number of 3.3, equating to over 3,500 kilometers per hour. The SR 71 Blackbird stands as a model for Supersonic speed. Furthermore, an exciting development is the SR 72, the next generation of this aircraft, currently in the developmental phase. It is projected to embark on its inaugural test flight in 2025, with an anticipated speed exceeding Mach 6.0, which amounts to approximately 7,400 kilometers per hour. Consequently, the SR 72 will be classified in the Hypersonic category, considering speeds ranging from Mach 5.0 to Mach 10.0.
The Sonic Boom
A most intriguing facet of Supersonic aircraft is the phenomenon of the sonic boom. When these aircraft breach the sound barrier, they generate a sonic boom, an auditory event that leaves an indelible impression. This signature boom occurs due to the aircraft’s ability to outpace sound waves. As a passenger jet moves through the air at Subsonic speeds, sound waves assume a particular curvature. However, when an aircraft is capable of Supersonic velocities, the intensity of its speed leads to the overlapping of sound waves. This collision of sound waves produces an abrupt, deafening noise akin to a thunderous explosion, heralding the passage of a Supersonic aircraft. For individuals on the ground underneath the path of a Supersonic jet, the experience is unmistakable—listening to the sonic boom is akin to hearing an enormous sonic clap, reminiscent of a balloon bursting as air pressure is suddenly released.
The visual accompaniment often associated with Supersonic travel is the formation of vapor clouds surrounding the aircraft during flight. Nevertheless, these cloud formations can also be a feature of Transonic aircraft under specific conditions. This effect occurs when Transonic planes traverse moist air. In situations of elevated humidity, the plummeting air pressure around the wings is accompanied by a corresponding temperature drop. This atmospheric interplay prompts moisture in the air to coalesce into visible cloud formations. Although these cloud formations can indeed occur in proximity to Supersonic aircraft breaking the sound barrier, it is imperative to comprehend that the mere presence of these cloud formations does not signify Supersonic flight.
I will now proceed to expound on the turn of events following the Concorde crash and its enduring implications.
History of Supersonic Flights
The journey through the annals of Supersonic flights unveils a captivating narrative. While the technology may appear cutting-edge, its origins date back to 1947 when Major Charles Yeager of the US Air Force achieved the remarkable feat of breaking the sound barrier. On October 14th, 1947, he piloted an aircraft at supersonic speeds, heralding a historic moment in aviation history above the Mojave Desert in America.
Following this breakthrough, the world of business magnates and commercial airlines cast a keen eye on supersonic aircraft. Their inquiry was straightforward: Why reserve these marvels of engineering solely for military applications? They aspired to develop supersonic aircraft accessible to ordinary passengers and embarked on a decade-long journey to transform this aspiration into reality.
However, the early 1960s marked a pivotal juncture in this trajectory. The intense Cold War rivalry between the United States and the Soviet Union diverted the focus of the US aerospace industry toward the realm of space exploration. The allure of moon landings and spacecraft eclipsed the quest for supersonic passenger planes, prompting a notable shift in the center of gravity for supersonic developments to Europe.
The Ascent of the Concorde Airliner
A significant turning point occurred when France and Britain joined forces in a multi-billion-dollar agreement for supersonic research. This collaboration materialized with the formal signing of the Concorde Agreement in 1962, a groundbreaking accord. Their collective mission was to construct a supersonic jetliner expressly designed for passenger travel, not military applications.
This vision bore fruit in March 1969 when the Concorde aircraft successfully completed its inaugural flight. Subsequently, over the course of a few years, the Concorde earned the distinction of being the world’s premier supersonic passenger flight. It marked a departure from the exclusive domain of the military, opening the skies to civilians who could now experience the thrill of supersonic travel. Underpinned by the slogan “Arrive Before You Leave,” the Concorde efficiently bridged the Atlantic Ocean, shuttling passengers between Europe and America in half the time of conventional aircraft.
What set the Concorde apart was its distinctive nose, which could be adjusted by tilting it upwards and downwards. During takeoffs and landings, this dynamic feature ensured optimal visibility for the pilots. When airborne, the nose could be raised to enhance aerodynamics. In terms of capacity, the Concorde was relatively compact, accommodating a mere 100 passengers initially. However, with time, the interior underwent a transformation, evolving from simplicity to luxury. Given the premium cost of tickets, as only the affluent could afford them, the airlines saw fit to enhance the interiors, introducing opulent features like caviar and champagne. Traveling on the Concorde became emblematic of prestige and status, attracting an array of luminaries, including superstars, celebrities, sports icons, and politicians. Notably, even former British Prime Minister Tony Blair embarked on this remarkable aircraft.
During its illustrious career, the Concorde maintained an impeccable safety record, free from any flight incidents for over 25 years. Safety and luxury were twin priorities. However, all of this changed tragically on July 25, 2000, when Air France flight 4590, as previously described, ended in disaster. The plane crashed near Paris, resulting in the loss of all 109 lives on board. Subsequent investigations revealed that a 17-inch metal piece left on the runway by a previous flight had been propelled into the Concorde’s tire upon takeoff, initiating a catastrophic sequence of events that led to the crash.
This catastrophic incident sent shockwaves worldwide, as it shattered the widely held belief that flying on the Concorde was inherently safe, akin to the misconception surrounding the “unsinkable” Titanic. Subsequently, both Air France and British Airways chose to temporarily suspend all Concorde flights while investigations unfolded. In November 2001, they cautiously reintroduced Concorde flights, but the industry faced several insurmountable challenges. The crash had cast a pall over the Concorde’s reputation, and the September 2001 attacks on the World Trade Center ushered in a period of anxiety and reduced air travel. The Concorde’s thunderous sonic boom, a marvel to behold initially, transformed into a source of disturbance for those residing in its flight path. This prompted a shift in flight routes to limit disruptions, directing Concorde flights primarily over the ocean instead of populated land areas.
As a result of these factors, the once-glorious Concorde faced a decline, leading to its eventual downfall.
Fuel consumption posed yet another significant issue for the Concorde. Compared to conventional passenger airplanes, the Concorde’s fuel consumption was a staggering four times higher. This was detrimental both from an environmental and economic perspective. To compound these challenges, the costs associated with maintaining and operating these supersonic planes were exorbitant. For instance, British Airways incurred an annual expense of £1 billion back then, which, when adjusted for inflation, amounts to approximately £1.7 billion today.
From a passenger’s viewpoint, spending a substantial sum, around ₹1.5 million, for the sake of swift travel seemed less justifiable when confronted with the Concorde’s relatively cramped seating. The spacious comfort of business or first-class seats seemed a more appealing option. The Concorde’s demand dwindled, further exacerbated by the crash, ultimately leading to increasingly vacant flights.
These myriad challenges culminated in Air France and British Airways jointly deciding to discontinue their Concorde flights in 2003. On October 24, 2003, the last commercial Concorde flight took off, marking the end of an era and signaling the conclusion of supersonic commercial flight.
Strikingly, nearly two decades later, supersonic aircraft are poised for a resurgence. Startups like Boom are actively developing supersonic planes, with United Airlines having placed orders for 15 of Boom’s Overture Aircraft, designed to reach Mach 1.7. If these endeavors succeed, supersonic aircraft may return to the skies by 2029. The environmental impact, a pressing concern, is being addressed through the use of sustainable aviation fuels and carbon-neutral manufacturing methods. While the Overture Aircraft may not match the Concorde’s Mach 2.0 speed, it will still significantly reduce travel times, potentially shrinking a Dubai-to-Singapore flight from 7 hours to just 4.
In an aviation landscape that often sees technological progress, the revival of supersonic flight demonstrates a unique and promising reversal.
