Visitors looks at the flying car Pegasus 1, built by French entrepreneur Jerome Dauffy at Paris Air Show, in Le Bourget, east of Paris, France, Tuesday, June 20, 2017. Aviation professionals and spectators are expected at this week's Paris Air Show, coming in, in a thousands from around the world to make business deals. (Photo by Michel Euler/AP Photo)

Hot air balloons take to the skies over Bristol city centre on August 6, 2012 in Bristol, England. The early morning flight of over twenty balloons over the city was organised as a curtain raiser for the four-day Bristol International Balloon Fiesta which starts on Thursday. Now in its 34th year, the Bristol International Balloon Fiesta is Europe's largest annual hot air balloon event in the city that is seen by many balloonists as the home of modern ballooning. (Photo by Matt Cardy)

“The Boeing X-45 unmanned combat air vehicle is a concept demonstrator for a next generation of completely autonomous military aircraft, developed by Boeing's Phantom Works. Manufactured by Boeing Integrated Defense Systems, the X-45 was a part of DARPA's J-UCAS project”. – Wikipedia

Photo: Two X-45A Unmanned Combat Air Vehicles (UCAV) are shown to members of the news media July 11, 2002 at Edwards Air Force Base, California. The X-45A, developed by The Defense Advanced Research Projects Agency and the Boeing Company, is the first unmanned system designed from inception for combat missions. (Photo by David McNew/Getty Images)

A woman wearing a scarf to cover her face looks on as she waits for a passenger bus on a smoggy morning in New Delhi, India, November 8, 2017. The Great Smog of Delhi is an ongoing severe air-pollution event in New Delhi and adjoining areas in the National Capital Territory of India, in November 2017. Air pollution at this time peaked on both PM 2.5 and PM 10 levels. It has been reported as one of the worst levels of air quality in Delhi since 1999. (Photo by Saumya Khandelwal/Reuters)

United States Air Force Academy graduates cheer as the United States Air Force Thunderbirds fly over the graduation for the Class of 2021 at Falcon Stadium on May 26, 2021 in Colorado Springs, Colorado. Chairman of the Joint Chiefs of Staff General Mark A. Milley gave the commencement address to the 1,019 graduates from the academy. (Photo by Michael Ciaglo/Getty Images)

Vendor Yegor Dyachkovsky, 45, poses for a picture at an open-air market on a frosty day in Yakutsk, Russia, January 15, 2023. Yakutsk, one of the Russia's north-most cities, is hit by an extreme cold snap as the air temperature on Sunday (January 15) plunged as low as minus 51 degrees Celsius (minus 59.8 degrees Fahrenheit). (Photo by Roman Kutukov/Reuters)

Breath of an Arctic fox by Marco Gaiotti, Italy. Marco was watching this little Arctic fox as it incessantly called another nearby. Gradually he noticed the fox’s wet breath was quickly freezing in the air after each call. It was late winter in Spitsbergen, Svalbard, and the air was -35C (-31F). Photographing Arctic foxes is often frustrating, as they are normally running around fast in search of food, but this one was very relaxed and let Marco get close enough to focus on it, with the light glowing perfectly in the background. (Photo by Marco Gaiotti/Wildlife Photographer of the Year 2021)

Family of passengers onboard AirAsia flight QZ8501 react at a waiting area in Juanda International Airport, Surabaya December 28, 2014. Indonesia's air force was searching for the AirAsia plane carrying 162 people that went missing on Sunday after the pilots asked to change course to avoid bad weather during a flight from the Indonesian city of Surabaya to Singapore. The Airbus 320-200 lost contact with Jakarta air traffic control at 6:17 a.m. (23:17 GMT), officials said. (Photo by Reuters/Beawiharta)