Poppy, a female Crowned sifaka, inspects a photographer's camera in the enclosure at the zoo of Mulhouse, eastern France, on March 5, 2019. The Crowned sifaka is a critically endangered species from Madagascar. (Photo by Sebastien Bozon/AFP Photo)

A Vietnamese cosplayer poses as police officer character from the game during the League of Legends (LOL) Mid-Season Invitational 2019 play-in group stage, in GG Stadium, Ho Chi Minh, Vietnam May 5, 2019. (Photo by Reuters/Kham)

An abandoned protection masks in the deserted building near bypass channel for cooling at the Chernobyl nuclear power plant in the Exclusion Zone, Ukraine, April 5, 20177. The Chernobyl nuclear accident occurred on 26 April 1986 in the No.4 light water graphite moderated reactor at the Chernobyl Nuclear Power Plant near Pripyat. An estimated 47,000 people of the city of Pripyat were evacuated after the explosion in 1986. (Photo by Vitaliy Holovin/Corbis via Getty images)

Pakistani vendors carry animals in a bus for the upcoming Muslim festival Eid al-Adha in Lahore, Pakistan, Monday, August 5, 2019. Eid al-Adha, or Feast of Sacrifice, is the most important Islamic holiday and marks the willingness of the Prophet Ibrahim (Abraham to Christians and Jews) to sacrifice his son. (Photo by K.M. Chaudhry/AP Photo)

Members of the Knights Guard clean the ice during the Vegas Golden Knights' game against the Anaheim Ducks at T-Mobile Arena on January 14, 2021 in Las Vegas, Nevada. The Golden Knights defeated the Ducks 5-2. (Photo by Ethan Miller/Getty images/Profimedia)

“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

5-year-old Chinese girl Wang Anna prepares meals for her grandmother and great-grandmother at home in Zhuyuan village, Guizhou province, China on March 3, 2017. Chinese girl called Wang Anna, 5, takes care of her ill grandmother and 92-year-old great-grandmother on her own every day in a mountainous village in Zhima town, Zunyi city, southwest China's Guizhou province. Her father went to jail before she was born and her mother remarried after gave birth to her. Although she is just five years old, she started to shoulder the responsibility to look after ill grandmother and elderly great-grandmother. (Photo by Imaginechina/Rex Features/Shutterstock)

A girl salutes to visitors before a show at the Mangyongdae Children's Palace in central Pyongyang, North Korea May 5, 2016. Pyongyang held a gala of song and dance performances by local school children on May 5 for visiting delegations of foreign journalists and tourists at the Mangyongdae Children's Palace. The event included orchestral, choir, and acrobatic performances, many of them with political undertones. The Seventh Worker's Party Congress commences on May 6, 2016. (Photo by Damir Sagolj/Reuters)