SUMMARY / RELATED TOPICS

Aerial firefighting

Aerial firefighting is the use of aircraft and other aerial resources to combat wildfires. The types of aircraft used include fixed-wing helicopters. Smokejumpers and rappellers are classified as aerial firefighters, delivered to the fire by parachute from a variety of fixed-wing aircraft, or rappelling from helicopters. Chemicals used to fight fires may include water, water enhancers such as foams and gels, specially formulated fire retardants such as Phos-Chek; the idea of fighting forest fires from the air dates back at least as far as Friedrich Karl von Koenig-Warthausen's observations on seeing a blaze when overflying the Santa Lucia Range, California, in 1929. A wide variety of terminology has been used in the popular media for the aircraft used in aerial firefighting; the terms airtanker or air tanker refer to fixed-wing aircraft based in the United States. The term "waterbomber" is used in some Canadian government documents for the same class of vehicles, though it sometimes has a connotation of amphibians.

Air attack is an industry term used for the actual application of aerial resources, both fixed-wing and rotorcraft, on a fire. Within the industry, though, "air attack" may refer to the supervisor in the air who supervises the process of attacking the wildfire from the air, including fixed-wing airtankers and any other aviation resources assigned to the fire; the Air Tactical Group Supervisor called "air attack," is flying at an altitude above other resources assigned to the fire in a fixed-wing plane but in a helicopter. Depending on the size and assessed potential of the wildfire, the "air attack" or ATGS person may be charged with initial attack, or with extended attack, the ongoing response to and management of a major wildfire requiring additional resources including engines, ground crews, other aviation personnel and aircraft needed to control the fire and establish control lines or firelines ahead of the wildfire. A wide variety of helicopters and fixed-wing aircraft are used for aerial firefighting.

In 2003, it was reported that "The U. S. Forest Service and Bureau of Land Management own, lease, or contract for nearly 1,000 aircraft each fire season, with annual expenditures in excess of US$250 million in recent years". Helicopters may be fitted with tanks or they may carry buckets; some helitankers, such as the Erickson AirCrane, are outfitted with a front-mounted foam cannon. Buckets are filled by submerging or dipping them in lakes, reservoirs, or portable tanks; the most popular of the buckets is the flexible Bambi Bucket. Tanks can be filled on the ground or water can be siphoned from lakes, reservoirs, or a portable tank through a hanging snorkel. Popular firefighting helicopters include variants of the Bell 204, Bell 205, Bell 212, Boeing Vertol 107, Boeing Vertol 234 and the Sikorsky S-64 Aircrane helitanker, which features a snorkel for filling from a natural or man-made water source while in hover; the world's largest helicopter, the Mil Mi-26, uses a Bambi bucket. Airtankers or water bombers are fixed-wing aircraft fitted with tanks that can be filled on the ground at an air tanker base or, in the case of flying boats and amphibious aircraft, by skimming water from lakes, reservoirs, or large rivers without needing to land.

Various aircraft have been used over the years for firefighting. In 1947, the United States Air Force and United States Forest Service experimented with military aircraft dropping water-filled bombs; the bombs were unsuccessful, the use of internal water tanks was adopted instead. Though World War II- and Korean War-era bombers were for a long time the mainstay of the aerial firefighting fleet, newer purpose-built tankers have since come online; the smallest are the Single Engine Air Tankers. These are agricultural sprayers that drop about 800 US gallons of water or retardant. Examples include the Air Tractor AT-802, which can deliver around 800 US gallons of water or fire retardant solution in each drop, the Soviet Antonov An-2 biplane. Both of these aircraft can be fitted with floats that scoop water from the surface of a body of water. Similar in configuration to the World War II–era Consolidated PBY Catalina, the Canadair CL-215 and its derivative the CL-415 are designed and built for firefighting.

The Croatian Air Force uses six CL-415s as well as six AT 802s for firefighting purposes. Medium-sized modified aircraft include the Grumman S-2 Tracker as used by the California Department of Forestry & Fire Protection, as well as the Conair Firecat version developed and used by Conair Group Inc. of Canada, while the Douglas DC-4, the Douglas DC-7, the Lockheed C-130 Hercules, the Lockheed P-2 Neptune, the Lockheed P-3 Orion – and its commercial equivalent, the L-188 Electra – have been used as air tankers. Conair converted a number of Convair 580 and Fokker F27 Friendship turboprop airliners to air tankers; the largest aerial firefighter used is a Boeing 747 aerial firefighter, known as the Global Supertanker, that can carry 19,600 US gallons fed by a pressurized drop system. The Supertanker was deployed operationally for the first time in 2009; the tanker made its first American operation on August 2009 at the Oak Glen Fire. It has since been replaced by a Boeing 747-400. Another wide body jetliner, being used as an air tanker is

Henry Taylor (artist)

Henry Taylor is an American artist and painter who lives and works in Los Angeles, California. Taylor is most well known for his acrylic paintings, mixed media sculptures, installations. Henry Taylor was born the youngest of eight brothers and sisters in Ventura, California, to a father, employed by the U. S. is listed as a painter on Henry's birth certificate. Raised in Oxnard, Henry took art classes at Oxnard College under James Jarvaise, who became an ongoing mentor. After 10 years of working as a psychiatric technician at Camarillo State Mental Hospital, Taylor retired in 1997, he attended the California Institute for the Arts, where in 1995, he obtained his Bachelor's of Fine Art. Taylor's largest output of work is in portraiture: he is known to paint obsessively, on various materials, including empty cigarette packs, detergent boxes, cereal boxes, crates, bottles and stretched canvas, his subjects include family, patients, strangers, celebrities, homeless people and historical figures, cultural figures, sports heroes and individuals from photographs or other art works.

At times, Taylor collapses time periods and spaces, as in Cicely and Miles Visit the Obamas: in this work, Cicely Tyson and Miles Davis—painted after a famous photograph of the couple from 1968—are seen in front of the White House, alluding to their imaginary visit to the Obamas. Taylor's painterly style has been variously described as sensuous, bold and loose, full of empathy and love, the visual equivalent to blues music, while retaining a profound critical social sensibility, his work has been lauded for maintaining an impossible balance between careful and sophisticated art-world references with a spontaneous and natural expressiveness. Taylor's oeuvre has been aligned within various American lineages, including the portraiture tradition of Alice Neel, the work of Harlem Renaissance painters such as Jacob Lawrence and Romare Bearden, compared with his peer Kerry James Marshall. Taylor's important exhibitions include a mid-career retrospective at MoMA PS1, along with solo exhibitions at the Studio Museum in Harlem and the Santa Monica Museum of Art, along with group exhibitions at the Whitney Museum of American Art, the Corcoran Gallery of Art, the Museum of Contemporary Art, Los Angeles, the Hammer Museum, the Carnegie Museum of Art, the Rubell Museum, the Bruce High Quality Foundation.

Taylor is represented by Feur Mesler gallery in New York. "I paint everyone. I try to capture the moment I am with someone who could be my friend, a neighbor, a celebrity, or a homeless person.”"It takes courage to do a lot of things. But, in a way, it doesn’t take courage, because you are free to do it. It’s like jumping in the water; the water's cold. You’ve gotta just jump in all the fucking time."

Hexagon

In geometry, a hexagon is a six-sided polygon or 6-gon. The total of the internal angles of any simple hexagon is 720°. A regular hexagon has Schläfli symbol and can be constructed as a truncated equilateral triangle, t, which alternates two types of edges. A regular hexagon is defined as a hexagon, both equilateral and equiangular, it is bicentric, meaning that it is both tangential. The common length of the sides equals the radius of the circumscribed circle or circumcircle, which equals 2 3 times the apothem. All internal angles are 120 degrees. A regular hexagon has 6 rotational symmetries and 6 reflection symmetries, making up the dihedral group D6; the longest diagonals of a regular hexagon, connecting diametrically opposite vertices, are twice the length of one side. From this it can be seen that a triangle with a vertex at the center of the regular hexagon and sharing one side with the hexagon is equilateral, that the regular hexagon can be partitioned into six equilateral triangles. Like squares and equilateral triangles, regular hexagons fit together without any gaps to tile the plane, so are useful for constructing tessellations.

The cells of a beehive honeycomb are hexagonal for this reason and because the shape makes efficient use of space and building materials. The Voronoi diagram of a regular triangular lattice is the honeycomb tessellation of hexagons, it is not considered a triambus, although it is equilateral. The maximal diameter, D, is twice the maximal radius or circumradius, R, which equals the side length, t; the minimal diameter or the diameter of the inscribed circle, d, is twice the minimal radius or inradius, r. The maxima and minima are related by the same factor: 1 2 d = r = cos ⁡ R = 3 2 R = 3 2 t and d = 3 2 D; the area of a regular hexagon A = 3 3 2 R 2 = 3 R r = 2 3 r 2 = 3 3 8 D 2 = 3 4 D d = 3 2 d 2 ≈ 2.598 R 2 ≈ 3.464 r 2 ≈ 0.6495 D 2 ≈ 0.866 d 2. For any regular polygon, the area can be expressed in terms of the apothem a and the perimeter p. For the regular hexagon these are given by a = r, p = 6 R = 4 r 3, so A = a p 2 = r ⋅ 4 r 3 2 = 2 r 2 3 ≈ 3.464 r 2. The regular hexagon fills the fraction 3 3 2 π ≈ 0.8270 of its circumscribed circle.

If a regular hexagon has successive vertices A, B, C, D, E, F and if P is any point on the circumcircle between B and C PE + PF = PA + PB + PC + PD. It follows from the ratio of circumradius to inradius that the height-to-width ratio of a regular hexagon is 1:1.1547005. The regular hexagon has Dih6 symmetry, order 12. There are 3 dihedral subgroups: Dih3, Dih2, Dih1, 4 cyclic subgroups: Z6, Z3, Z2, Z1; these symmetries express 9 distinct symmetries of a regular hexagon. John Conway labels these by a group order. R12 is full symmetry, a1 is no symmetry. P6, an isogonal hexagon constructed by three mirrors can alternate long