The city of Meroë laid undiscovered for two millennia before British archaeologist John Garstang excavated it in the early 20th century. Garstang took the radical decision to document his discoveries with photography – and immortalised an ancient world. “Meroë: Africa’s Forgotten Empire” is being shown until 14 September at Garstang Museum of Archaeology, Liverpool. Here: A group visiting the excavations at Meroë, including (from left) Midwinter Bey, director of Sudan Railways; Lord Kitchener; General Sir Francis Reginald Wingate, Sirdar of the Egyptian Army; Professor Archibald Sayce; John Garstang; and Lady Catherine Wingate, 1911. (Photo by Garstang Museum of Archaeology)

A People's Liberation Army (PLA) commando jumps through a fire hoop part of an exercise during an open day event at the Ngong Shuen Chau Barracks, the PLA navy base in the territory, in Hong Kong, China, 01 July 2015. Thousands of visitors attended the PLA open day yesterday and today to mark the 16th anniversary of the handover from British rule. (Photo by Jerome Favre/EPA)

Number 10. BELL H-13 SIOUX was a two-bladed, single engine, light helicopter built by Bell Helicopter. Westland Aircraft manufactured the Sioux under license for the British military as the Sioux AH.1 and HT. In 1947, the United States Air Force ordered the improved Bell Model 47A. Most were designated YR-13 and three winterized versions were designated YR-13A. The United States Army first ordered Bell 47s in 1948 under the designation H-13. These would later receive the name Sioux. The Bell-built H-13 B is seen airborne in this April 29, 1951 photo. The helicopter is equipped with a 173 horsepower engine, cruises at 85 miles per hour, climbs 900 feet in a minute and has a service ceiling of 11,500 feet. (Photo by AP Photo)

Members of the Indian Army display aerobatic Taekwondo skills during the 11th Reunion and 262nd Anniversary of Army Service Crops in Bangalore, India, 09 December 2022. The 11th ASC Reunion & 262nd Corps Day will be held at Army Service Corps (ASC) Centre & College on 8th and 9th of December 2022, to showcase the military capabilities. Indian Army Service Corps, established in 1760, is an arm of the Indian Army handling logistic support. (Photo by Jagadeesh N.V./EPA/EFE/Rex Features/Shutterstock)

U.S Army combat camera photographer Spc. Hilda Clayton took this photo July 2, 2013 that was released by the U.S. Army, that shows an Afghan soldier engulfed in flame as a mortar tube explodes during an Afghan National Army live-fire training exercise in Laghman Province, Afghanistan. The accident killed Clayton and four Afghan National Army soldiers. (Photo by Spc. Hilda Clayton/U.S. Army via AP Photo)

“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

An Israeli soldier leaves the battlefield after an army exercise on at the Shizafon army base, in the Negev Desert north of the southern city of Eilat on January 31, 2012 in Shizafon, Israel. (Photo by Uriel Sinai/Getty Images)

Members of ASC Tornados, the motorcycle display team of the Indian army, lie in a row on the ground as another performs a stunt by jumping over them during the 225th anniversary celebrations of Army Service Corps in Bangalore, India, Tuesday, December 8, 2015. The Army Service Corps which was established in 1790 is an arm of the Indian Army which handles its logistic support function. (Photo by Aijaz Rahi/AP Photo)