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87-415: Cursuses range in length from 50 yards (46 m) to almost 6 miles (9.7 km). The distance between the parallel earthworks can be up to 100 yards (91 m). Banks at the terminal ends enclose the cursus. Over fifty have been identified via aerial photography while many others have doubtless been obliterated by farming and other activities. The Stonehenge Cursus is a notable example within sight of

174-402: A buoyant force that does not require lateral movement through the surrounding air mass to effect a lifting force. By contrast, aerodynes primarily use aerodynamic lift , which requires the lateral movement of at least some part of the aircraft through the surrounding air mass. Some things that fly do not generate propulsive thrust through the air, for example, the flying squirrel . This

261-626: A public space is considered outside the realm of privacy in the United States, aerial photography may legally document features and occurrences on private property. The FAA can pursue enforcement action against persons operating model aircraft who endanger the safety of the national airspace system. Public Law 112–95, section 336(b). June 21, 2016, the FAA released its summary of small unmanned aircraft rules (Part 107). The rules established guidelines for small UAS operators including operating only during

348-451: A rocket launch , which provides the initial thrust to overcome the force of gravity and propels the spacecraft from the surface of the Earth. Once in space, the motion of a spacecraft—both when unpropelled and when under propulsion—is covered by the area of study called astrodynamics . Some spacecraft remain in space indefinitely, some disintegrate during atmospheric reentry , and others reach

435-732: A space without contacting any planetary surface , either within an atmosphere (i.e. air flight or aviation ) or through the vacuum of outer space (i.e. spaceflight ). This can be achieved by generating aerodynamic lift associated with gliding or propulsive thrust , aerostatically using buoyancy , or by ballistic movement. Many things can fly, from animal aviators such as birds , bats and insects , to natural gliders/parachuters such as patagial animals, anemochorous seeds and ballistospores , to human inventions like aircraft ( airplanes , helicopters , airships , balloons , etc.) and rockets which may propel spacecraft and spaceplanes . The engineering aspects of flight are

522-562: A 624 square miles (1,620 km ) area in Palestine as an aid to correcting and improving maps of the Turkish front. This was a pioneering use of aerial photography as an aid for cartography . Lieutenants Leonard Taplin , Allan Runciman Brown , H. L. Fraser, Edward Patrick Kenny , and L. W. Rogers photographed a block of land stretching from the Turkish front lines 32 miles (51 km) deep into their rear areas. Beginning 5 January, they flew with

609-404: A balloon between Hammam-Lif and Grombalia . The first use of a motion picture camera mounted to a heavier-than-air aircraft took place on April 24, 1909, over Rome in the 3:28 silent film short, Wilbur Wright und seine Flugmaschine . The use of aerial photography rapidly matured during the war, as reconnaissance aircraft were equipped with cameras to record enemy movements and defenses. At

696-801: A business with major contracts in Africa and Asia as well as in the UK. Operations began from the Stag Lane Aerodrome at Edgware, using the aircraft of the London Flying School. Subsequently, the Aircraft Manufacturing Company (later the De Havilland Aircraft Company ), hired an Airco DH.9 along with pilot entrepreneur Alan Cobham . From 1921, Aerofilms carried out vertical photography for survey and mapping purposes. During

783-484: A few are listed below. Vertical photographs are often used to create orthophotos , alternatively known as orthophotomaps , photographs which have been geometrically "corrected" so as to be usable as a map. In other words, an orthophoto is a simulation of a photograph taken from an infinite distance, looking straight down to nadir . Perspective must obviously be removed, but variations in terrain should also be corrected for. Multiple geometric transformations are applied to

870-481: A fighter escort to ward off enemy fighters. Using Royal Aircraft Factory BE.12 and Martinsyde airplanes, they not only overcame enemy air attacks, but also had to contend with 65 mph (105 km/h) winds, antiaircraft fire, and malfunctioning equipment to complete their task. The first commercial aerial photography company in the UK was Aerofilms Ltd, founded by World War I veterans Francis Wills and Claude Graham White in 1919. The company soon expanded into

957-496: A first sighting of cropmarks visible from aerial reconnaissance; for example, the cropmarks at Fetteresso were the first indication of a cursus at that location in Aberdeenshire , Scotland . 'Cursus' (plural 'cursūs' or 'cursuses') was a name given by early British archaeologists such as William Stukeley to the large parallel lengths of banks with external ditches which they thought were early Roman athletic courses , after

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1044-630: A flying fish was 45 seconds. Most birds fly ( see bird flight ), with some exceptions. The largest birds, the ostrich and the emu , are earthbound flightless birds , as were the now-extinct dodos and the Phorusrhacids , which were the dominant predators of South America in the Cenozoic era. The non-flying penguins have wings adapted for use under water and use the same wing movements for swimming that most other birds use for flight. Most small flightless birds are native to small islands, and lead

1131-427: A heavier aircraft gliding at a higher airspeed will arrive at the same touchdown point in a shorter time. Air pressure acting up against an object in air is greater than the pressure above pushing down. The buoyancy, in both cases, is equal to the weight of fluid displaced - Archimedes' principle holds for air just as it does for water. A cubic meter of air at ordinary atmospheric pressure and room temperature has

1218-483: A high vantage structures , suspended on cables (e.g. Skycam ) or on top of very tall poles that are either handheld (e.g. monopods and selfie sticks ), fixed firmly to ground (e.g. surveillance cameras and crane shots ) or mounted above vehicles . Aerial photography was first practiced by the French photographer and balloonist Gaspard-Félix Tournachon , known as "Nadar" , in 1858 over Paris , France. However,

1305-564: A lifestyle where flight would offer little advantage. Among living animals that fly, the wandering albatross has the greatest wingspan, up to 3.5 meters (11 feet); the great bustard has the greatest weight, topping at 21 kilograms (46 pounds). Most species of insects can fly as adults. Insect flight makes use of either of two basic aerodynamic models: creating a leading edge vortex, found in most insects, and using clap and fling , found in very small insects such as thrips . Many species of spiders , spider mites and lepidoptera use

1392-411: A mass of about 1.2 kilograms, so its weight is about 12 newtons . Therefore, any 1-cubic-meter object in air is buoyed up with a force of 12 newtons. If the mass of the 1-cubic-meter object is greater than 1.2 kilograms (so that its weight is greater than 12 newtons), it falls to the ground when released. If an object of this size has a mass less than 1.2 kilograms, it rises in the air. Any object that has

1479-923: A mass of more than 20 kg are termed 'Large Model Aircraft' – within the UK, large model aircraft may only be flown in accordance with an exemption from the ANO, which must be issued by the CAA. Photographs taken at an angle are called oblique photographs . If they are taken from a low angle relative to the earth's surface, they are called low oblique and photographs taken from a high angle are called high or steep oblique . Vertical photographs are taken straight down. They are mainly used in photogrammetry and image interpretation . Pictures that will be used in photogrammetry are traditionally taken with special large format cameras with calibrated and documented geometric properties. Aerial photographs are often combined. Depending on their purpose it can be done in several ways, of which

1566-601: A mass that is less than the mass of an equal volume of air will rise in air - in other words, any object less dense than air will rise. Thrust-to-weight ratio is, as its name suggests, the ratio of instantaneous thrust to weight (where weight means weight at the Earth 's standard acceleration g 0 {\displaystyle g_{0}} ). It is a dimensionless parameter characteristic of rockets and other jet engines and of vehicles propelled by such engines (typically space launch vehicles and jet aircraft ). If

1653-470: A pair of flat gliding surfaces. "Flying" snakes also use mobile ribs to flatten their body into an aerodynamic shape, with a back and forth motion much the same as they use on the ground. Flying fish can glide using enlarged wing-like fins, and have been observed soaring for hundreds of meters. It is thought that this ability was chosen by natural selection because it was an effective means of escape from underwater predators. The longest recorded flight of

1740-582: A perception of depth that could aid in cartography and in intelligence derived from aerial images. The Royal Flying Corps recon pilots began to use cameras for recording their observations in 1914 and by the Battle of Neuve Chapelle in 1915, the entire system of German trenches was being photographed. In 1916 the Austro-Hungarian Monarchy made vertical camera axis aerial photos above Italy for map-making. The first purpose-built and practical aerial camera

1827-534: A planetary or lunar surface for landing or impact. In 2018, researchers at Massachusetts Institute of Technology (MIT) managed to fly an aeroplane with no moving parts, powered by an " ionic wind" also known as electroaerodynamic thrust. Many human cultures have built devices that fly, from the earliest projectiles such as stones and spears, the boomerang in Australia , the hot air Kongming lantern , and kites . George Cayley studied flight scientifically in

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1914-626: A reality in the 20th century following theoretical and practical breakthroughs by Konstantin Tsiolkovsky and Robert H. Goddard . The first orbital spaceflight was in 1957, and Yuri Gagarin was carried aboard the first crewed orbital spaceflight in 1961. There are different approaches to flight. If an object has a lower density than air, then it is buoyant and is able to float in the air without expending energy. A heavier than air craft, known as an aerodyne , includes flighted animals and insects, fixed-wing aircraft and rotorcraft . Because

2001-455: A retarding force called drag. Because lift and drag are both aerodynamic forces, the ratio of lift to drag is an indication of the aerodynamic efficiency of the airplane. The lift to drag ratio is the L/D ratio, pronounced "L over D ratio." An airplane has a high L/D ratio if it produces a large amount of lift or a small amount of drag. The lift/drag ratio is determined by dividing the lift coefficient by

2088-500: A special rule for model aircraft. In Section 336, Congress confirmed the FAA's long-standing position that model aircraft are aircraft. Under the terms of the Act, a model aircraft is defined as "an unmanned aircraft" that is "(1) capable of sustained flight in the atmosphere; (2) flown within visual line of sight of the person operating the aircraft; and (3) flown for hobby or recreational purposes." Because anything capable of being viewed from

2175-465: A technique called ballooning to ride air currents such as thermals , by exposing their gossamer threads which gets lifted by wind and atmospheric electric fields . Mechanical flight is the use of a machine to fly. These machines include aircraft such as airplanes , gliders , helicopters , autogyros , airships , balloons , ornithopters as well as spacecraft . Gliders are capable of unpowered flight. Another form of mechanical flight

2262-452: A ten-inch lens and took photos from 23,000 feet. Each photo covered two hundred and twenty-five square miles. One of its first government contracts was an aerial survey of New Mexico to study soil erosion. A year later, Fairchild introduced a better high altitude camera with nine-lens in one unit that could take a photo of 600 square miles with each exposure from 30,000 feet. In 1939 Sidney Cotton and Flying Officer Maurice Longbottom of

2349-470: A timer to take photographs from the air. The same year, Cecil Shadbolt devised a method of taking photographs from the basket of a gas balloon , including shots looking vertically downwards. One of his images, taken from 2,000 feet (610 m) over Stamford Hill , is the earliest extant aerial photograph taken in the British Isles. A print of the same image, An Instantaneous Map Photograph taken from

2436-468: A video mapping program. This "Spatial Multimedia" is the timely union of digital media including still photography, motion video, stereo, panoramic imagery sets, immersive media constructs, audio, and other data with location and date-time information from the GPS and other location designs. Aerial videos are emerging Spatial Multimedia which can be used for scene understanding and object tracking. The input video

2523-418: Is perpendicular to the flow direction. Aerodynamic lift results when the wing causes the surrounding air to be deflected - the air then causes a force on the wing in the opposite direction, in accordance with Newton's third law of motion . Lift is commonly associated with the wing of an aircraft , although lift is also generated by rotors on rotorcraft (which are effectively rotating wings, performing

2610-439: Is a system that remains aloft primarily through the use of buoyancy to give an aircraft the same overall density as air. Aerostats include free balloons , airships , and moored balloons . An aerostat's main structural component is its envelope , a lightweight skin that encloses a volume of lifting gas to provide buoyancy , to which other components are attached. Aerostats are so named because they use "aerostatic" lift,

2697-408: Is captured by low flying aerial platforms and typically consists of strong parallax from non-ground-plane structures. The integration of digital video, global positioning systems (GPS) and automated image processing will improve the accuracy and cost-effectiveness of data collection and reduction. Several different aerial platforms are under investigation for the data collection. In film production, it

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2784-469: Is common to use a unmanned aerial vehicle with a mounted cine camera. For example, the AERIGON cinema drone is used for low aerial shots in big blockbuster movies. [REDACTED] Media related to Aerial photography at Wikimedia Commons [REDACTED] The dictionary definition of aerial photography at Wiktionary Flight Flight or flying is the process by which an object moves through

2871-404: Is equal to the drag D divided by the (density r times half the velocity V squared times the reference area A). [Cd = D / (A * .5 * r * V^2)] Lift-to-drag ratios for practical aircraft vary from about 4:1 for vehicles and birds with relatively short wings, up to 60:1 or more for vehicles with very long wings, such as gliders. A greater angle of attack relative to the forward movement also increases

2958-413: Is flight faster than the speed of sound . Supersonic flight is associated with the formation of shock waves that form a sonic boom that can be heard from the ground, and is frequently startling. The creation of this shockwave requires a significant amount of energy; because of this, supersonic flight is generally less efficient than subsonic flight at about 85% of the speed of sound. Hypersonic flight

3045-440: Is para-sailing, where a parachute-like object is pulled by a boat. In an airplane, lift is created by the wings; the shape of the wings of the airplane are designed specially for the type of flight desired. There are different types of wings: tempered, semi-tempered, sweptback, rectangular and elliptical. An aircraft wing is sometimes called an airfoil , which is a device that creates lift when air flows across it. Supersonic flight

3132-450: Is pushed in the direction opposite to flight. This can be done in several ways including by the spinning blades of a propeller , or a rotating fan pushing air out from the back of a jet engine , or by ejecting hot gases from a rocket engine . The forward thrust is proportional to the mass of the airstream multiplied by the difference in velocity of the airstream. Reverse thrust can be generated to aid braking after landing by reversing

3219-617: Is sometimes suggested as a related or continual folk tradition with the Neolithic cursus. Larger scale modern ceremonial analogs might include the National Mall in Washington, and The Mall, London . Numerous examples of cursus are known and the discipline of aerial archaeology is the most effective method of identifying such large features following thousands of years of weathering and plough damage. Some cursus have only been identified through

3306-648: Is termed ballistic flight . Examples include balls , arrows , bullets , fireworks etc. Essentially an extreme form of ballistic flight, spaceflight is the use of space technology to achieve the flight of spacecraft into and through outer space . Examples include ballistic missiles , orbital spaceflight , etc. Spaceflight is used in space exploration , and also in commercial activities like space tourism and satellite telecommunications . Additional non-commercial uses of spaceflight include space observatories , reconnaissance satellites and other Earth observation satellites . A spaceflight typically begins with

3393-493: Is termed gliding . Some other things can exploit rising air to climb such as raptors (when gliding) and man-made sailplane gliders . This is termed soaring . However most other birds and all powered aircraft need a source of propulsion to climb. This is termed powered flight. The only groups of living things that use powered flight are birds , insects , and bats , while many groups have evolved gliding. The extinct pterosaurs , an order of reptiles contemporaneous with

3480-422: Is the radio controlled Nitrohawk helicopter developed by Robert Channon between 1988 and 1998. In addition to gyroscopically stabilized footage, the use of RC copters as reliable aerial photography tools increased with the integration of FPV (first-person-view) technology. Many radio-controlled aircraft, in particular drones, are now capable of utilizing Wi-Fi to stream live video from the aircraft's camera back to

3567-417: Is used in cartography (particularly in photogrammetric surveys , which are often the basis for topographic maps ), land-use planning, aerial archaeology . Oblique aerial photography is used for movie production , environmental studies, power line inspection, surveillance , construction progress, commercial advertising, conveyancing , and artistic projects. An example of how aerial photography

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3654-518: Is used in the field of archaeology is the mapping project done at the site Angkor Borei in Cambodia from 1995 to 1996. Using aerial photography, archaeologists were able to identify archaeological features, including 112 water features (reservoirs, artificially constructed pools and natural ponds) within the walled site of Angkor Borei. In the United States, aerial photographs are used in many Phase I Environmental Site Assessments for property analysis. In

3741-455: Is very high speed flight where the heat generated by the compression of the air due to the motion through the air causes chemical changes to the air. Hypersonic flight is achieved primarily by reentering spacecraft such as the Space Shuttle and Soyuz . Some things generate little or no lift and move only or mostly under the action of momentum, gravity, air drag and in some cases thrust. This

3828-630: The Latin word cursus , meaning "course". Aerial photography Aerial photography (or airborne imagery ) is the taking of photographs from an aircraft or other airborne platforms. When taking motion pictures , it is also known as aerial videography . Platforms for aerial photography include fixed-wing aircraft , helicopters , unmanned aerial vehicles (UAVs or "drones"), balloons , blimps and dirigibles , rockets , pigeons , kites , or using action cameras while skydiving or wingsuiting . Handheld cameras may be manually operated by

3915-537: The RAF were among the first to suggest that airborne reconnaissance may be a task better suited to fast, small aircraft which would use their speed and high service ceiling to avoid detection and interception. Although this seems obvious now, with modern reconnaissance tasks performed by fast, high flying aircraft, at the time it was radical thinking. They proposed the use of Spitfires with their armament and radios removed and replaced with extra fuel and cameras. This led to

4002-529: The dinosaurs , were also very successful flying animals, and there were apparently some flying dinosaurs (see Flying and gliding animals#Non-avian dinosaurs ). Each of these groups' wings evolved independently , with insects the first animal group to evolve flight. The wings of the flying vertebrate groups are all based on the forelimbs, but differ significantly in structure; insect wings are hypothesized to be highly modified versions of structures that form gills in most other groups of arthropods . Bats are

4089-560: The photographer , while mounted cameras are usually remotely operated or triggered automatically. Aerial photography typically refers specifically to bird's-eye view images that focus on landscapes and surface objects, and should not be confused with air-to-air photography , where one or more aircraft are used as chase planes that "chase" and photograph other aircraft in flight. Elevated photography can also produce bird's-eye images closely resembling aerial photography (despite not actually being aerial shots) when telephotoing from

4176-482: The thrust-to-weight ratio is greater than the local gravity strength (expressed in g s), then flight can occur without any forward motion or any aerodynamic lift being required. If the thrust-to-weight ratio times the lift-to-drag ratio is greater than local gravity then takeoff using aerodynamic lift is possible. Flight dynamics is the science of air and space vehicle orientation and control in three dimensions. The three critical flight dynamics parameters are

4263-900: The 1930s, the company pioneered the science of photogrammetry (mapping from aerial photographs), with the Ordnance Survey amongst the company's clients. In 1920, the Australian Milton Kent started using a half-plate oblique aero camera purchased from Carl Zeiss AG in his aerial photographic business. Another successful pioneer of the commercial use of aerial photography was the American Sherman Fairchild who started his own aircraft firm Fairchild Aircraft to develop and build specialized aircraft for high altitude aerial survey missions. One Fairchild aerial survey aircraft in 1935 carried unit that combined two synchronized cameras, and each camera having five six inch lenses with

4350-481: The Arran cursus the most significant he had seen in his career. It has been conjectured that they were used in rituals connected with ancestor veneration , that they follow astronomical alignments or that they served as buffer zones between ceremonial and occupation landscapes. More recent studies have reassessed the original interpretation and argued that they were used for ceremonial competitions. Finds of arrowheads at

4437-582: The Car of a Balloon, 2,000 feet high , was shown at the 1882 Photographic Society exhibition. Frenchman Arthur Batut began using kites for photography in 1888, and wrote a book on his methods in 1890. Samuel Franklin Cody developed his advanced 'Man-lifter War Kite' and succeeded in interesting the British War Office with its capabilities. In 1908, Albert Samama Chikly filmed the first ever aerial views using

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4524-560: The Civil Aviation Safety Authority (CASA). Whilst a small RPAS and model aircraft may actually be identical, unlike model aircraft, a RPAS may enter controlled airspace with approval, and operate close to an aerodrome. Due to a number of illegal operators in Australia making false claims of being approved, CASA maintains and publishes a list of approved remote operator's certificate (ReOC) holders. However, CASA has modified

4611-404: The FAA. Small scale model aircraft offer increased photographic access to these previously restricted areas. Miniature vehicles do not replace full-size aircraft, as full-size aircraft are capable of longer flight times, higher altitudes, and greater equipment payloads. They are, however, useful in any situation in which a full-scale aircraft would be dangerous to operate. Examples would include

4698-544: The Special Rule for Model Aircraft", banned the commercial use of unmanned aircraft over U.S. airspace. On September 26, 2014, the FAA began granting the right to use drones in aerial filmmaking. Operators are required to be licensed pilots and must keep the drone in view at all times. Drones cannot be used to film in areas where people might be put at risk. The FAA Modernization and Reform Act of 2012 established, in Section 336,

4785-486: The UK has tight regulations as to where a drone is able to fly. Aerial Photography on Light aircraft under 20 kg (44 lb). Basic Rules for non commercial flying Of a SUA (Small Unmanned Aircraft). Article 241 Endangering safety of any person or property. A person must not recklessly or negligently cause or permit an aircraft to endanger any person or property. Article 94 small unmanned aircraft Article 95 small unmanned surveillance aircraft Model aircraft with

4872-596: The United States, except when necessary for take-off and landing, full-sized manned aircraft are prohibited from flying at altitudes under 1000 feet over congested areas and not closer than 500 feet from any person, vessel, vehicle or structure over non-congested areas. Certain exceptions are allowed for helicopters, powered parachutes and weight-shift-control aircraft. Advances in radio controlled models have made it possible for model aircraft to conduct low-altitude aerial photography. This had benefited real-estate advertising, where commercial and residential properties are

4959-601: The angles of rotation in three dimensions about the vehicle's center of mass , known as pitch , roll and yaw (See Tait-Bryan rotations for an explanation). The control of these dimensions can involve a horizontal stabilizer (i.e. "a tail"), ailerons and other movable aerodynamic devices which control angular stability i.e. flight attitude (which in turn affects altitude , heading ). Wings are often angled slightly upwards- they have "positive dihedral angle " which gives inherent roll stabilization. To create thrust so as to be able to gain height, and to push through

5046-492: The camera parts freezing. Based at RAF Medmenham , the collection and interpretation of such photographs became a considerable enterprise. Cotton's aerial photographs were far ahead of their time. Together with other members of the 1 PRU, he pioneered the techniques of high-altitude, high-speed stereoscopic photography that were instrumental in revealing the locations of many crucial military and intelligence targets. According to R.V. Jones , photographs were used to establish

5133-400: The car stable on the road. For a solid object moving through a fluid, the drag is the component of the net aerodynamic or hydrodynamic force acting opposite to the direction of the movement. Therefore, drag opposes the motion of the object, and in a powered vehicle it must be overcome by thrust . The process which creates lift also causes some drag. Aerodynamic lift is created by

5220-486: The craft is heavier than air, it must generate lift to overcome its weight . The wind resistance caused by the craft moving through the air is called drag and is overcome by propulsive thrust except in the case of gliding . Some vehicles also use thrust in the place of lift; for example rockets and Harrier jump jets . Forces relevant to flight are These forces must be balanced for stable flight to occur. A fixed-wing aircraft generates forward thrust when air

5307-451: The daytime, a 400 ft (120 m). ceiling and pilots must keep the UAS in visual range. April 7, 2017, the FAA announced special security instructions under 14 CFR § 99.7. Effective April 14, 2017, all UAS flights within 400 feet of the lateral boundaries of U.S. military installations are prohibited unless a special permit is secured from the base and/or the FAA. Aerial photography in

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5394-498: The development of the Spitfire PR variants. Spitfires proved to be extremely successful in their reconnaissance role and there were many variants built specifically for that purpose. They served initially with what later became No. 1 Photographic Reconnaissance Unit (PRU). In 1928, the RAF developed an electric heating system for the aerial camera. This allowed reconnaissance aircraft to take pictures from very high altitudes without

5481-443: The drag coefficient, CL/CD. The lift coefficient Cl is equal to the lift L divided by the (density r times half the velocity V squared times the wing area A). [Cl = L / (A * .5 * r * V^2)] The lift coefficient is also affected by the compressibility of the air, which is much greater at higher speeds, so velocity V is not a linear function. Compressibility is also affected by the shape of the aircraft surfaces. The drag coefficient Cd

5568-418: The end of the war, aerial cameras had dramatically increased in size and focal power and were used increasingly frequently as they proved their pivotal military worth; by 1918 both sides were photographing the entire front twice a day and had taken over half a million photos since the beginning of the conflict. In January 1918, General Allenby used five Australian pilots from No. 1 Squadron AFC to photograph

5655-411: The extent of deflection, and thus generates extra lift. However a greater angle of attack also generates extra drag. Lift/drag ratio also determines the glide ratio and gliding range. Since the glide ratio is based only on the relationship of the aerodynamics forces acting on the aircraft, aircraft weight will not affect it. The only effect weight has is to vary the time that the aircraft will glide for –

5742-458: The first half of the 19th century, and in the second half of the 19th century Otto Lilienthal made over 200 gliding flights and was also one of the first to understand flight scientifically. His work was replicated and extended by the Wright brothers who made gliding flights and finally the first controlled and extended, manned powered flights. Spaceflight, particularly human spaceflight became

5829-540: The ground more closely. Leaf-on photographs are used to measure crop health and yield . For forestry purposes, some species of trees are easier to distinguish from other kinds of trees with leaf-off photography, while other species are easier to distinguish with leaf-on photography. With advancements in video technology, aerial video is becoming more popular. Orthogonal video is shot from aircraft mapping pipelines, crop fields, and other points of interest. Using GPS, video may be embedded with meta data and later synced with

5916-521: The hands of field commanders in record time. Frederick Charles Victor Laws started aerial photography experiments in 1912 with No.1 Squadron of the Royal Flying Corps (later No. 1 Squadron RAF ), taking photographs from the British dirigible Beta . He discovered that vertical photos taken with a 60% overlap could be used to create a stereoscopic effect when viewed in a stereoscope, thus creating

6003-591: The image, depending on the perspective and terrain corrections required on a particular part of the image. Orthophotos are commonly used in geographic information systems , such as are used by mapping agencies (e.g. Ordnance Survey ) to create maps. Once the images have been aligned, or "registered", with known real-world coordinates, they can be widely deployed. Large sets of orthophotos, typically derived from multiple sources and divided into "tiles" (each typically 256 x 256 pixels in size), are widely used in online map systems such as Google Maps . OpenStreetMap offers

6090-432: The inspection of transformers atop power transmission lines and slow, low-level flight over agricultural fields, both of which can be accomplished by a large-scale radio-controlled helicopter. Professional-grade, gyroscopically stabilized camera platforms are available for use under such a model; a large model helicopter with a 26cc gasoline engine can hoist a payload of approximately seven kilograms (15 lbs). One example

6177-851: The more famous Stonehenge stone circle. Other examples are the four cursuses at Rudston in Yorkshire , that at Fornham All Saints in Suffolk , the Cleaven Dyke in Perthshire and the Dorset cursus . The Bures cursus and the Metlands cursus are in Bures St Mary , Suffolk, and were detected from cropmarks . They are situated just above the floodplain of the north bank of the River Stour, Suffolk . On 21 December each year

6264-663: The motion of an aerodynamic object (wing) through the air, which due to its shape and angle deflects the air. For sustained straight and level flight, lift must be equal and opposite to weight. In general, long narrow wings are able deflect a large amount of air at a slow speed, whereas smaller wings need a higher forward speed to deflect an equivalent amount of air and thus generate an equivalent amount of lift. Large cargo aircraft tend to use longer wings with higher angles of attack, whereas supersonic aircraft tend to have short wings and rely heavily on high forward speed to generate lift. However, this lift (deflection) process inevitably causes

6351-427: The only mammals capable of sustaining level flight (see bat flight ). However, there are several gliding mammals which are able to glide from tree to tree using fleshy membranes between their limbs; some can travel hundreds of meters in this way with very little loss in height. Flying frogs use greatly enlarged webbed feet for a similar purpose, and there are flying lizards which fold out their mobile ribs into

6438-555: The photographic subject. In 2014 the US Federal Aviation Administration banned the use of drones for photographs in real estate advertisements. The ban has been lifted and commercial aerial photography using drones of UAS is regulated under the FAA Reauthorization Act of 2018. Commercial pilots have to complete the requirements for a Part 107 license, while amateur and non-commercial use is restricted by

6525-510: The photographs he produced no longer exist and therefore the earliest surviving aerial photograph is titled 'Boston, as the Eagle and the Wild Goose See It.' Taken by James Wallace Black and Samuel Archer King on October 13, 1860, it depicts Boston from a height of 630m. Kite aerial photography was pioneered by British meteorologist E.D. Archibald in 1882. He used an explosive charge on

6612-699: The pilot's or pilot in command's (PIC) ground station. In Australia, Civil Aviation Safety Regulation Part 101 (CASR Part 101) allows for commercial use of unmanned and remotely piloted aircraft. Under these regulations, unmanned remotely piloted aircraft for commercial are referred to as Remotely Piloted Aircraft Systems (RPAS), whereas radio-controlled aircraft for recreational purposes are referred to as model aircraft. Under CASR Part 101, businesses/persons operating remotely piloted aircraft commercially are required to hold an operator certificate, just like manned aircraft operators. Pilots of remotely piloted aircraft operating commercially are also required to be licensed by

6699-410: The pitch of variable-pitch propeller blades, or using a thrust reverser on a jet engine. Rotary wing aircraft and thrust vectoring V/STOL aircraft use engine thrust to support the weight of the aircraft, and vector sum of this thrust fore and aft to control forward speed. In the context of an air flow relative to a flying body, the lift force is the component of the aerodynamic force that

6786-466: The position of pre-existing long barrows and bank barrows and appear to ignore difficulties in terrain. The Dorset Cursus , the longest known example, crosses a river and three valleys along its course across Cranborne Chase and is close to the henge monuments at Knowlton . The present-day Tynwald day ceremony on the Isle of Man involves the procession of parliament along a cursus-like structure, which

6873-410: The purview of aerospace engineering which is subdivided into aeronautics , the study of vehicles that travel through the atmosphere, and astronautics , the study of vehicles that travel through space, and ballistics , the study of the flight of projectiles. Humans have managed to construct lighter-than-air vehicles that raise off the ground and fly, due to their buoyancy in the air. An aerostat

6960-448: The regulations and from September 29, 2016, drones under 2 kg (4.4 lb) may be operated for commercial purposes. 2006 FAA regulations grounding all commercial RC model flights have been upgraded to require formal FAA certification before permission is granted to fly at any altitude in the US. June 25, 2014, The FAA, in ruling 14 CFR Part 91 [Docket No. FAA–2014–0396] "Interpretation of

7047-427: The same function without requiring that the aircraft move forward through the air). While common meanings of the word " lift " suggest that lift opposes gravity, aerodynamic lift can be in any direction. When an aircraft is cruising for example, lift does oppose gravity, but lift occurs at an angle when climbing, descending or banking. On high-speed cars, the lift force is directed downwards (called "down-force") to keep

7134-521: The size and the characteristic launching mechanisms for both the V-1 flying bomb and the V-2 rocket . Cotton also worked on ideas such as a prototype specialist reconnaissance aircraft and further refinements of photographic equipment. At the peak, the British flew over 100 reconnaissance flights a day, yielding 50,000 images per day to interpret. Similar efforts were taken by other countries. Vertical aerial photography

7221-407: The start of the conflict, the usefulness of aerial photography was not fully appreciated, with reconnaissance being accomplished with map sketching from the air. Germany adopted the first aerial camera, a Görz , in 1913. The French began the war with several squadrons of Blériot observation aircraft equipped with cameras for reconnaissance. The French Army developed procedures for getting prints into

7308-506: The sun rises over Lodge Hills, Wormingford, and shines down the length of the Metlands cursus. In the summer of 2023 excavation began at a cursus discovered near Drumadoon in the Isle of Arran in 2019. It is believed to be the only complete example in Britain. Archaeologists from Glasgow University co-led by Dr Kenneth Brophy and local volunteers began excavating at the site in August. Brophy judged

7395-432: The terminal ends suggest archery and hunting were important to the builders and that the length of the cursus may have reflected its use as a proving ground for young men involving a journey to adulthood. Anthropological parallels exist for this interpretation. Contemporary internal features are rare and it has been traditionally thought that the cursūs were used as processional routes. They are often aligned on and respect

7482-417: The use of similar orthophotos for deriving new map data. Google Earth overlays orthophotos or satellite imagery onto a digital elevation model to simulate 3D landscapes. Aerial photography may be labeled as either "leaf-off" or on "leaf-on" to indicate whether deciduous foliage is in the photograph. Leaf-off photographs show less foliage or no foliage at all, and are used to see the ground and things on

7569-605: Was invented by Captain John Moore-Brabazon in 1915 with the help of the Thornton-Pickard company, greatly enhancing the efficiency of aerial photography. The camera was inserted into the floor of the aircraft and could be triggered by the pilot at intervals. Moore-Brabazon also pioneered the incorporation of stereoscopic techniques into aerial photography, allowing the height of objects on the landscape to be discerned by comparing photographs taken at different angles. By

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