An autumn leaf sticks to a bench near the Bishops Castle near Wells Cathedral on November 1, 2011 in Wells, England. According to a number of nature watchers the autumn colours are currently reaching their peak following an unusually warm September and October which has led to trees holding onto their leaves longer than normal. (Photo by Matt Cardy/Getty Images)

Druids, pagans and revellers cheer as the sun rises at Stonehenge on December 22, 2011 in Wiltshire, England. The unseasonable warm weather encouraged a larger than normal crowd to gather at the famous historic stone circle to celebrate the sunrise closest to the Winter Solstice, the shortest day of the year. (Photo by Matt Cardy/Getty Images)

“Igor Sikorsky (May 25, 1889 – October 26, 1972), born Igor Ivanovich Sikorsky was a Russian American pioneer of aviation in both helicopters and fixed-wing aircraft. He designed and flew the world's first multi-engine fixed-wing aircraft, the Russky Vityaz in 1913, and the first airliner, Ilya Muromets, in 1914. After immigrating to the United States in 1919, Sikorsky founded the Sikorsky Aircraft Corporation in 1923, and developed the first of Pan American Airways' ocean-conquering flying boats in the 1930s. In 1939 Sikorsky designed and flew the Vought-Sikorsky VS-300, the first viable American helicopter, which pioneered the rotor configuration used by most helicopters today. Sikorsky would modify the design into the Sikorsky R-4, which became the world's first mass-produced helicopter in 1942”. – Wikipedia

Photo: Westland Sikorsky H-5's, used by British European Airways Helicopters, which fly between London and Birmingham. The Sikorsky H-5, (aka R-5, S-51, HO3S-1, or Horse) (R-5 until 1948; company designation VS-327) is a helicopter built by Sikorsky Aircraft Corporation, formerly used by the United States Air Force, and its predecessor, the United States Army Air Forces, as well as the United States Navy and United States Coast Guard (with the designations HO2S and HO3S). (Photo by Harrison /Topical Press Agency/Getty Images). 22nd May 1951

A woman waits at a polio immunisation health centre, in Maiduguri, Borno State, Nigeria, August 29, 2016. Nigeria's military has liberated large swathes of land from Boko Haram but a ride with an army convoy, all guns firing for fear of ambush, shows how far the northeast is from normality after a brutal Islamist insurgency that has displaced millions. (Photo by Afolabi Sotunde/Reuters)

Visitors enjoy food at a table bounded by a banner with a character fast food restaurant Kentucky Fried Chicken, in Jakarta, Indonesia, on June 23, 2020. The display banner is useful for limiting physical distance for visitors who eat on the spot. The Indonesian government has imposed a new set of regulations known as “new normal”, which will be implemented in stages starting in early June for some provinces. (Photo by Jefta Images/Barcroft Media via Getty Images)

A vendor pushes an improvised cart with a woman and merchandise along a rarely used rail track in Bangkok, Thailand, Thursday, June 25, 2020. Daily life in the capital slowly returns to normal as the Thai government eases many restrictions imposed weeks ago to combat the spread of COVID-19. Though emergency regulations require the use of face masks in public, some residents have become apathetic as Thailand has record zero local transmission for over three weeks. (Photo by Gemunu Amarasinghe/AP Photo)

Chinese women dressed in traditional costumes and wearing masks visit a popular shopping street in Wuhan in central China's Hubei province, Saturday, January 23, 2021. A year after it was locked down to contain the spread of coronavirus, the central Chinese city of Wuhan has largely returned to normal, even as China continues to battle outbreaks elsewhere in the country. (Photo by Ng Han Guan/AP Photo)