The longest eclipse viewing flight in history

In 1973, scientists used the Concorde supersonic aircraft to extend the eclipse observation time to 74 minutes while flying nearly as fast as the Moon's shadow moving across the Earth.

On April 8, JSX Airlines had a flight to view the solar eclipse over Dallas. Both United Airlines and Delta sold out tickets for the flight across the total spectrum on the journey from Texas to Northeast. But no aircraft can compare to what Concorde 001 did on June 30, 1973, when it chased the Moon's shadow along the Tropic of Cancer during a total solar eclipse.

Concorde supersonic aircraft chased the shadow of the Moon in 1973. (Photo: Grant Faint).

Flying at an altitude of 17,000m, the world's fastest supersonic aircraft extends the eclipse observation time from a maximum of 7 minutes and 4 seconds on the ground to 74 minutes. For seven observers from France, Britain and the United States, this was the longest flight to view a total solar eclipse in human history. Although the supersonic aircraft has long been discontinued, Concorde's historic 1973 flight is still legendary among eclipse chasers.

On June 30, 1973, the Concorde plane took off from Las Palmas, Gran Canaria, on the Canary Islands of Spain. The band of totality that day was about 251km wide with the Moon's shadow moving at 2,400km/h. Concorde flew at a speed of 2,200km/h (Mach 2) along the path of totality in the same direction as the Moon's shadow, thereby maintaining the eclipse observation time as long as possible. Longer eclipse observation periods allow scientists to study the Sun's corona and chromosphere, as well as the intensity of sunlight from above Earth's atmosphere.

The Concorde 001 prototype first flew at Toulouse Airport, France on March 2, 1969. (Photo: Tony Eyles/Mirrorpix).

Scientists on board were from Los Alamos National Laboratory, Paris Observatory, Kitt Peak Observatory, Queen Mary University of London, University of Aberdeen, and the French National Center for Scientific Research. Concorde 001 was modified specifically for them, with a window hole in the roof for observation equipment. After takeoff, the Concorde chased the shadow of the Moon above Mauritania . Over the next four minutes, it flew over the Sahara in Mali, Nigeria and Niger before being overtaken by the Moon's shadow. The vehicle landed in Chad.

The 1973 flight was not the last time Concorde flew in the Moon's shadow during a total solar eclipse. 20 years later, on August 11, 1999, three Concordes, one from France and two from England, carried passengers into the shadow of the Moon. Their eclipse viewing time lasted 4 - 5 minutes instead of about 2 minutes on the ground. However, passengers had problems observing the eclipse for more than 30 seconds due to the small window and the position of the Sun.

Those were Concorde's last flights into full range. After the fatal accident of Air France flight 4590 on July 25, 2000, the solar eclipse viewing flight on June 21, 2001 was canceled. The most successful eclipse viewing flight in recent years was E-Flight 2019-MAX which took place on July 2, 2019, doubling the observing time from 4 minutes 32 seconds to 9 minutes.