When Concorde Chased a Solar Eclipse

This is the tale of a group of researchers who managed to observe a solar eclipse on board Concorde.



April 8, 2024

DALLAS — In 1973, a select team of astronomers from various countries used the prototype Concorde aircraft to their advantage in their quest to witness a long solar eclipse.

In light of today's total solar eclipse special flights by various U.S. airlines, we delve into the remarkable tale of researchers who endeavored to observe a solar eclipse from the unique perspective of the fastest commercial airplane ever built.

To understand the significance of Scientists chasing a solar eclipse aboard Concorde, we must first appreciate the extraordinary characteristics of this iconic aircraft. Concorde is prominent in the history of air travel and aerospace engineering. Developed and manufactured jointly by British Aerospace and Aérospatiale, this supersonic jet revolutionized the concept of commercial flying.

Besides its delta wing shape, the key feature that set the Concorde apart was its remarkable speed. Capable of cruising at speeds exceeding Mach 2 (approximately 1,354 mph or 2,180 km/h), the Concorde was twice as fast as the speed of sound.

It could whisk passengers across the Atlantic Ocean in just under three and a half hours, dramatically reducing travel time compared to conventional subsonic aircraft. In addition to its impressive speed, Concorde was renowned for its ability to fly at altitudes of around 60,000 feet (18,300 meters). Operating at such heights offered several advantages.

Firstly, it allowed the Concorde to fly above most weather systems, minimizing turbulence and ensuring a smoother ride for passengers. Secondly, the higher altitude reduced air resistance, resulting in fuel efficiency and enabling the aircraft to maintain supersonic speeds for longer.

Secondly, flying at such heights granted passengers a unique perspective of Earth and the sky. They could witness the planet's curvature and experience breathtaking views of the celestial sphere.

In the context of chasing a solar eclipse, the Concorde's speed and altitude capabilities played a pivotal role. These attributes allowed researchers to access unique perspectives of the eclipse and observe it from a vantage point beyond conventional aircraft's reach.

Photo: Aerospatiale

An Idea Takes Flight

According to Vice, In May 1972, slightly more than a year before the celestial event, Pierre Léna, an astronomer from the Paris Observatory, presented his proposal to André Turcat, a French test pilot.

Turcat was highly impressed with the idea and presented it to his superiors at Aérospatiale, who provisionally approved it and agreed to cover the mission's expenses. The concept of observing a solar eclipse from Concorde was born from a collaboration between astronomers and aviation enthusiasts.

It was a bold plan to leverage the capabilities of Concorde to chase the shadow of a solar eclipse across the Earth's surface, thereby extending the duration of its totality and maximizing scientific observations.

The first challenge was pinpointing an upcoming solar eclipse and calculating its path and timing accurately. The researchers conducted astronomical calculations to determine the trajectory of the moon's shadow during the eclipse, taking into account the Concorde's speed, altitude, and flight capabilities.

Léna and Turcat performed extensive simulations and test flights to fine-tune the logistics and ensure the mission's feasibility.

Meanwhile, at the Astrophysics Department at Queen Mary College, London University, Dr John Beckman and other researchers were keen on making far-infrared eclipse observations to learn about the sun. "He put two and two together and came up with the answer - Concorde," recalls Jim Lesurf, ex-QMC student.

Lesurf had spent months developing and testing at QMC and flew to Aerospatiale's facilities in Toulouse at the start of May 1973.

Concorde prototype (F-WTSS). Photo: Aérospatiale

Astronomy Meets Aviation

The QMC research team —Léna, Lesurf, Jim Hall (RSRE), John Beckman, and Tony Marston— collaborated closely with Concorde pilots and navigators, sharing their expertise in celestial mechanics and eclipse predictions.

QMC wasn’t the only research team using 001 at the time. There were also researchers from Los Alamos in the US, two groups from France, and one from Aberdeen University. In addition, there was already an ongoing project run by Dr. Jim Birch of the UK National Physical Laboratory.

Together, they worked to synchronize Concorde's flight trajectory with the eclipse's path, aiming for a perfect interception that would provide an optimal viewing and research experience.

The planning also extended to the selection and preparation of the astronomer who would embark on the expedition. The chosen astronomer would need to have the scientific knowledge and observational skills required to study a solar eclipse and the adaptability to work in the unique environment of a supersonic jet.

Extensive training was provided to familiarize the research team with Concorde's operating procedures and safety protocols, ensuring a seamless integration of science and aviation.

As the idea gained momentum, excitement and anticipation grew among the scientific community and aviation enthusiasts alike. The prospect of witnessing a solar eclipse from Concorde's unrivaled vantage point generated a sense of wonder and anticipation.

The collaboration represented the convergence of two distinct fields - astronomy and aviation - and promised groundbreaking scientific research and discovery opportunities.

The mission was approved in February 1973, and there were only four months until the eclipse. The researchers hurriedly embarked on the final preparations.

Finally, on June 30, 1973, Concorde 001 took off in pursuit of the solar eclipse, marking the culmination of months of planning and preparation.


The Flight

With its crew and the chosen astronomer onboard, at precisely 10:08 am on the morning of June 30, the four twin-spool Olympus 593 engines beneath the sweeping delta wings of Concorde were ignited to full afterburner, propelling "001" down the runway of Gran Canaria Airport (LPA).

The successful execution of the mission depended on precise navigation and timing. The moment of interception approached as Concorde raced along its calculated flight path.

Traveling together at almost the same speed, Concorde would race the solar eclipse across the planet's surface by swooping down from the north and intercepting the moon's shadow over northwest Africa.

The astronomers and the entire crew anxiously awaited the announcement of totality. And then, in a remarkable display of precision and engineering, Concorde entered the eclipse's shadow, plunging the aircraft into ethereal darkness.

As Turcat kept 001 on its planned course, the astronomers witnessed the extraordinary phenomenon of totality from the four special portholes. The darkened skies revealed the Sun's corona, a delicate and shimmering crown surrounding the hidden solar disk. The scientific observations and Concorde could have continued, but the team had to prepare for the upcoming landing in Chad.

Each group concluded their observations and took a few moments to appreciate the unique sight of the Sahara sands. The researchers witnessed the complete eclipse for an unprecedented duration of 74 minutes.

After the test. Photo: PIERRE LÉNA via Jim Lesurf (ex-QMC student)


During a single flight, Concorde provided astronomers more time to observe the eclipse than all the expeditions conducted in the previous century combined.

Concorde's pursuit of a solar eclipse left a lasting legacy and significant scientific impact. This extraordinary endeavor not only pushed the boundaries of aviation but also provided invaluable opportunities for astronomical research and deepened our understanding of the Sun's behavior and structure.

One of the key scientific contributions of the Concorde solar eclipse chase was the extended duration of totality. By intercepting the eclipse's shadow and continuously flying within it, the astronomer aboard the Concorde gained precious extra minutes of observing time during the event.

This extended period of totality allowed for more detailed and comprehensive scientific observations of the Sun's corona, magnetic fields, and other phenomena that occur during eclipses.

The data collected during the chase contributed to advancements in solar physics and provided valuable insights into the intricate workings of our nearest star.

'Alpha Foxtrot' was the first Concorde to appear in BA's Chatham Historic Dockyard scheme.
Photo: Ken Fielding, CC BY-SA 3.0

Moreover, Concorde's unique vantage point offered an unattainable perspective from the ground or conventional aircraft. Flying around 60,000 feet above much of Earth's atmospheric interference provided an unobstructed eclipse view.

This unfiltered view allowed for detailed observations of the corona and other solar features, free from the distortions caused by Earth's atmosphere. The unprecedented observations from the Concorde's height increased our understanding of the Sun's outer atmosphere and dynamic behavior.

The astronomers' collaboration with Concorde highlighted the potential for future astronomical research and exploration from high-altitude platforms. The mission's success demonstrated the feasibility and benefits of using advanced aircraft to conduct scientific observations in the upper atmosphere.

It opened up new avenues for studying not only solar eclipses but also other celestial events and phenomena that the unique capabilities of high-altitude platforms could enhance.

Air France, British Airways Concorde. Photo: Airbus

Moon Shadow Flights

During the 1999 solar eclipse over Europe, three Concordes, one from France and two from Britain, briefly pursued the moon's shadow. However, the passengers on board were tourists.

The fatal crash of Concorde Flight 4590, which occurred shortly after takeoff from Paris on July 25, 2000, marked the beginning of the end for the Supersonic airliner.

The planned Concorde eclipse tours for 2001 were canceled, and in 2003, the final commercial Concorde flight landed for the last time.

Concorde landed at Farnborough in September 1974. Photo: Steve Fitzgerald,
GFDL 1.2

Final Thoughts

Concorde's chase of a solar eclipse was a testament to collaboration in pursuing knowledge. This endeavor not only pushed the boundaries of aviation but also deepened our understanding of the Sun and its celestial dance.

By extending the duration of totality and providing a unique vantage point, Concorde enabled valuable scientific observations and contributed to advancements in solar physics. The legacy of this remarkable mission continues to inspire future generations, reminding us of the power of exploration, innovation, and the unyielding spirit of human curiosity.

Although Concorde is no longer operational, its solar eclipse chase serves as a reminder of the remarkable achievements that can arise from collaboration between different disciplines and the relentless pursuit of pushing the boundaries of human knowledge.

The Concorde solar eclipse chase demonstrated the power of combining cutting-edge technology, scientific expertise, and the inherent curiosity of the human spirit to unlock the secrets of the universe.

Feature Image: Concorde chasing Solar Eclipse. The photo was credited to Arthur Gibson from an unknown source, Public Domain. Article by Bhavya Velani. Special thanks to Jim Lesurf (ex-QMC student) and his September 24, 2011, post on the QMC experiment as the primary source of this article.