“NASA's Pathfinder, Pathfinder Plus, Centurion and Helios Prototype were an evolutionary series of solar- and fuel-cell-system-powered unmanned aerial vehicles. AeroVironment, Inc. developed the vehicles under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. They were built to develop the technologies that would allow long-term, high-altitude aircraft to serve as “atmospheric satellites”, to perform atmospheric research tasks as well as serve as communications platforms”. – Wikipedia

Photo: The solar-electric Helios Prototype flying wing is flies over the Hawaiian islands of Niihau and Lehua during the first solar-powered test flight July 14, 2001 from the U.S. Navy's Pacific Missile Range Facility on Kauai, HI. The 18-hour flight was a functional checkout of the aircraft's systems and performance in preparation for an attempt to reach sustained flight at 100,000 feet altitude later in the summer. (Photo Courtesy of NASA/Getty Images)

The Haʻikū Stairs, also known as the Stairway to Heaven or Haʻikū Ladder, is a steep hiking trail on the island of Oʻahu. The trail began as a wooden ladder spiked to the cliff on the south side of the Haʻikū Valley. It was installed in 1942 to enable antenna cables to be strung from one side of the cliffs above Haʻikū Valley to the other. A building to provide a continuous communication link between Wahiawā and Haʻikū Valley Naval Radio Station was constructed at the peak of Puʻukeahiakahoe, elevation about 2,800 feet (850 m). The antennae transmitted very low frequency radio signals from a 200,000-watt Alexanderson alternator in the center of Haʻikū valley. The signals could reach US Navy submarines as far away as Tokyo Bay while the submarines were submerged.

“The Naval and Military Club is a gentlemen's club in London, England. It was founded in 1862 because the three then existing military clubs in London – the United Service, the Junior United Service and the Army and Navy – were all full. The membership was long restricted to military officers. This is no longer the case, but it still has a predominantly military and ex-military membership”. – Wikipedia

Photo: Members of the prestigious “In and Out Club”, one of the oldest and most exclusive clubs in London, march around St. James's Square during the club's 150th birthday celebration on March 1, 2012 in London, England. Patrons of the private members club, whose official title is the Naval and Military Club, gathered in St. James's Square in Central London before marching with the Band of the Royal Logistics Corps to be greeted by HRH The Duke of Edinburgh, and retiring for lunch inside the club. (Photo by Dan Kitwood/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

During a jungle survival program February 20, 2013 taught by Royal Thai Special Forces in Sannapit, Thailand, U.S. Marines learned to catch cobras and drink their fresh blood, not to mention eat forest insects and pull the heads off of chicken. The training was part of Operation Cobra Gold 13, the 32nd edition of international military exercises hosted by the Thai. According to a U.S. Marines press release, Cobra Gold is the largest exercise of its kind in Asia and incorporates troops from five other nations in addition to the U.S. and Thailand. The Daily Mail reports that the Marines were invited to experience the local custom of drinking cobra blood after being taught to catch and kill cobras in the wild. As CNN notes, Cobra blood is believed to be a panacea and aphrodiasic in parts of Southeast Asia. In Jakarta, vendors can earn over $100 a night selling shots of cobra blood mixed with liquor. (Photo by Pornchai Kittiwongsakul/AFP Photo)

Gymnasts from the Pyongyang Circus Theater perform during Mother's Day Monday, November 16, 2020, in Pyongyang, North Korea. (Photo by Jon Chol Jin/AP Photo)

North Korean soldiers keep watch at the bank of the Yalu River, near the North Korean town of Sinuiju, opposite Dandong in China's Liaoning province, September 10, 2016. (Photo by Thomas Peter/Reuters)

Competitors take part in the 8th annual World Gravy Wrestling Championships at the Rose n Bowl Pub in Bacup, north west England on August 31, 2015. Contestants must participate in fancy dress and wrestle in a pool of Lancashire Gravy for 2 minutes whilst being scored for a variety of wrestling moves. (Photo by Oli Scarff/AFP Photo)