Dutch cyclist Fabio Jakobsen's bicycle (behind, L) flies through the air as he collides with compatriot Dylan Groenewegen (on the ground, L) during the opening stage of the Tour of Poland race in Katowice, southern Poland on August 5, 2020. The Dutch rider was fighting for his life on Wednesday after he was thrown into and over a barrier at 80km/h in a sickening conclusion to the opening stage of the Tour of Poland. (Photo by Szymon Gruchalski/Forum/AFP Photo)

A fighter jet flies above as Ukrainian soldiers sit on an armoured personnel carrier in Kramatorsk, in eastern Ukraine April 16, 2014. Ukrainian government forces and separatist pro-Russian militia staged rival shows of force in eastern Ukraine on Wednesday amid escalating rhetoric on the eve of crucial four-power talks in Geneva on the former Soviet country's future. (Photo by Marko Djurica/Reuters)

NASA's DHC-3 Otter plane flies in Operation IceBridge-Alaska surveys of mountain glaciers in Alaska in this image released on September 18, 2014. Over the past few decades, average global temperatures have been on the rise, and this warming is happening two to three times faster in the Arctic. (Photo by Chris Larsen/Reuters/NASA/University of Alaska-Fairbanks)

A military aircraft flies low through the Mach Loop in west-central Wales on September 25, 2025 during Cobra Warrior 25-2, one of Nato’s largest multinational air exercises. The operation, running across the UK until October 3, brings together air forces from the UK, US, Canada, Italy and Germany for three weeks of high-intensity training in challenging low-level environments. (Photo by Tony Marsh)

“Contrails (short for “condensation trails”) or vapour trails are artificial clouds that are the visible trails of condensed water vapour made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets or, if the air is cold enough, tiny ice crystals”. – Wikipedia

Photo: An airplane leaves a vapor trail as it flies in front of he moon on January 17, 2007 above Hanover, Germany. (Photo by Alexander Hassenstein/Getty Images)

Michael Read, director of Flight Operations from New Zealand-based Martin Aircraft Company, flies a Martin Jetpack during a demonstration at a water park in Shenzhen, China December 6, 2015. KuangChi Science Ltd, a Hong Kong-listed Chinese company and investor of Martin Aircraft, will sell the flying machine in mainland China for 1.6 million yuan ($249,902), according to the company. (Photo by Bobby Yip/Reuters)

In this undated photo made available by journal Nature on January 15, 2014, a northern bald ibis (Geronticus eremita) flies in Tuscany, Italy. A new study released Wednesday, January 15, 2014 says the birds choreograph the flapping of their wings, getting a boost from an updraft of air in the wake of the flapping wings by flying behind the first bird and off to the side. When a flock of birds take advantage of these aerodynamics, they form a V. (Photo by Markus Unsöld/AP Photo)

A Polish MiG-29 flies beneath dark skies at the annual RNAS Yeovilton Air Day on July 9, 2011 in Yeovil, England. The annual air day at RNAS Yeovilton in Somerset, attracts over 35,000 people to what is one of the biggest air shows in the region and gives visitors the chance to see a host of aircraft as well as a number of historic and classic cars. (Photo by Matt Cardy/Getty Images)