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24-475: The Dolphin originated in 1930 as the "Sinbad," a pure flying boat without wheels. The Sinbad was intended as a luxurious flying yacht. Undaunted by the lack of demand, Douglas improved the Sinbad in 1931 so that it was amphibious, and could land on water or land. The improved aircraft was named "Dolphin", however this did not represent the end of development, as many detail improvements were made, including an increase in

48-423: A 75% reduction in processing and assembly time as well as a noticeable weight saving over traditional aluminium counterparts. Multiple instances of damage to the aft pressure bulkhead have occurred; while a few cases have led to serious failures leading to aircraft losses, others have proven to be survivable. Aviation certifying authorities have often mandated inspections of an aircraft's aft pressure bulkhead in

72-469: A fixed front section called the vertical stabiliser , used to control yaw, which is movement of the fuselage right to left motion of the nose of the aircraft. The rear section of the vertical fin is the rudder , a movable aerofoil that is used to turn the aircraft's nose right or left. When used in combination with the ailerons , the result is a banking turn, a coordinated turn , the essential feature of aircraft movement. Some aircraft are fitted with

96-499: A second wing in tandem arrangement). A "tailless" type usually still has a vertical stabilising fin ( vertical stabiliser ) and control surface ( rudder ). However, NASA adopted the "tailless" description for the novel X-36 research aircraft which has a canard foreplane but no vertical fin. The most successful tailless configuration has been the tailless delta , especially for combat aircraft. Rear pressure bulkhead The aft pressure bulkhead or rear pressure bulkhead

120-421: A single repair patch plate was incorrectly cut in two "to make it fit". Failure of the bulkhead damaged hydraulic pipes passing through. Boeing later calculated that the incorrect installation would be expected to fail after approximately 10,000 pressurizations; the repaired aircraft accomplished 12,318 successful flights before the crash. During 2013, National Airlines Flight 102 crashed after loose freight on

144-513: A stabilising empennage were virtually unflyable. Even so-called " tailless aircraft " usually have a tail fin (usually a vertical stabiliser ). Heavier-than-air aircraft without any kind of empennage (such as the Northrop B-2 ) are rare, and generally use specially shaped airfoils whose trailing edge provide pitch stability, and rearwards swept wings , often with dihedral to provide the necessary yaw stability. In some aircraft with swept wings,

168-404: A tail assembly that is hinged to pivot in two axes forward of the fin and stabiliser, in an arrangement referred to as a movable tail . The entire empennage is rotated vertically to actuate the horizontal stabiliser, and sideways to actuate the fin. The aircraft's cockpit voice recorder , flight data recorder and emergency locator transmitter (ELT) are often located in the empennage, because

192-466: Is called the horizontal stabiliser and is used to provide pitch stability. The rear section of the tailplane is called the elevator , and is a movable aerofoil that controls changes in pitch, the up-and-down motion of the aircraft's nose. In some aircraft the horizontal stabilizer and elevator are one unit, and to control pitch the entire unit moves as one. This is known as a stabilator or full-flying stabiliser . The vertical tail structure has

216-469: Is characterised by: Twin fins may be mounted at various points: Unusual fin configurations include: An alternative to the fin-and-tailplane approach is provided by the V-tail and X-tail designs. Here, the tail surfaces are set at diagonal angles, with each surface contributing to both pitch and yaw. The control surfaces, sometimes called ruddervators , act differentially to provide yaw control (in place of

240-583: Is the rear component of the pressure seal in all aircraft that cruise in a tropopause zone in the Earth's atmosphere. It helps maintain pressure when stratocruising and protects the aircraft from bursting due to the higher internal pressure. Aft pressure bulkheads can either be curved, which reduces the amount of metal needed at the cost of reducing the usable space in the airliner, or flat, which gives more internal space but also more weight. Patents have been filed that propose deliberately creating cavities within

264-580: The tail or tail assembly , is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow . The term derives from the French language verb empenner which means " to feather an arrow". Most aircraft feature an empennage incorporating vertical and horizontal stabilising surfaces which stabilise the flight dynamics of yaw and pitch , as well as housing control surfaces . In spite of effective control surfaces, many early aircraft that lacked

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288-620: The USCG RD-4 undertook some rescues of merchant sailors at sea, feats that made spectacular news reports, enthralling the American public. Data from:McDonnell Douglas Aircraft since 1920 Vol.1 Data from McDonnell Douglas Aircraft since 1920, Vol. 1 General characteristics Performance Aircraft of comparable role, configuration, and era Related lists Empennage The empennage ( / ˌ ɑː m p ɪ ˈ n ɑː ʒ / or / ˈ ɛ m p ɪ n ɪ dʒ / ), also known as

312-532: The aft of the aircraft provides better protection for these in most aircraft crashes. In some aircraft trim devices are provided to eliminate the need for the pilot to maintain constant pressure on the elevator or rudder controls. The trim device may be: Multi-engined aircraft often have trim tabs on the rudder to reduce the pilot effort required to keep the aircraft straight in situations of asymmetrical thrust, such as single engine operations. Aircraft empennage designs may be classified broadly according to

336-406: The airfoil section or angle of incidence may change radically towards the tip. Structurally, the empennage consists of the entire tail assembly, including the tailfin , the tailplane and the part of the fuselage to which these are attached. On an airliner this would be all the flying and control surfaces behind the rear pressure bulkhead . The front (usually fixed) section of the tailplane

360-410: The cause was determined to be corrosion of the rear pressure bulkhead by fluid contamination, perhaps from the lavatory. The corrosion was not detectable by the inspection techniques at the time. In 1985, Japan Airlines Flight 123 crashed after a catastrophic failure of the aft pressure bulkhead. The failure occurred due to faulty repair of the bulkhead after a tailstrike seven years earlier, when

384-472: The early 2000s, Airbus Group developed the largest manufactured resin film infusion structure then in production to function as the aft pressure bulkhead for their double-decker A380 airliner. the German aerospace supplier Premium AEROTEC , which successfully manufactured the world's first thermoplastic -based rear pressure bulkhead during the 2010s; according to the firm, the new unit had reportedly resulted in

408-432: The fin and tailplane configurations. The overall shapes of individual tail surfaces (tailplane planforms, fin profiles) are similar to wing planforms . The tailplane comprises the tail-mounted fixed horizontal stabiliser and movable elevator. Besides its planform , it is characterised by: Some locations have been given special names: The fin comprises the fixed vertical stabiliser and rudder. Besides its profile , it

432-556: The first successful Douglas airliners. Subsequent examples were ordered by the United States Navy and U.S. Coast Guard for use as transports and search and rescue craft. The U.S. Army Air Corps ordered several under the designations C-21 , C-26 , and C-29 . Many were eventually ordered for their original purpose as luxury transports. Owners included William Boeing , the founder of the Boeing Company , and Philip K. Wrigley ,

456-464: The interest of safety. Various techniques have been devised to determine the integrity of the rear pressure bulkhead; these have been used not only to inspect in-service examples but also in the design process, helping to design efficient bulkheads that possess sufficient strength to ensure a safe operational life. In 1971, British European Airways Flight 706 crashed in Belgium, killing all 63 on board;

480-497: The length of over a foot and changes made to the empennage , engine nacelles and wings. The Great Depression had curtailed demand for such extravagance as a "flying yacht", but Douglas managed to interest the United States Coast Guard who not only bought the Sinbad, but 12 Dolphins. The first two were purchased by Wilmington-Catalina Airlines to fly passengers between Los Angeles and Santa Catalina Island , becoming

504-632: The rear bulkhead with the purpose of providing more usable cabin space. On several airliners, production of the rear pressure bulkhead has been outsourced to third party manufacturers. While typically being a time-consuming and somewhat uncommon process, an aircraft's aft pressure bulkhead can be wholly replaced. During the twenty-first century, various parties became increasingly interested in developing aft pressure bulkheads composed from composite materials, seeking benefits such as lower manufacturing costs, easier sealing, elimination of corrosion risk, along with weight and part count reductions. During

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528-523: The rudder) and act together to provide pitch control (in place of the elevator). An outboard tail is split in two, with each half mounted on a short boom just behind and outboard of each wing tip. It comprises outboard horizontal stabilizers (OHS) and may or may not include additional boom-mounted vertical stabilizers (fins). In this position, the tail surfaces interact constructively with the wingtip vortices and, with careful design, can significantly reduce drag to improve efficiency, without adding unduly to

552-639: The son of the founder of the Wm. Wrigley Jr. Company . William K. Vanderbilt bought two with custom interiors for use from the Vanderbilt yacht Alva as flying tenders. One was procured by the U.S. Navy as a transport for President Franklin D. Roosevelt . Although never used by Roosevelt, this was the first aircraft procured to provide transportation for the President of the United States. In 1933, landing in heavy seas,

576-800: The structural loads on the wing. The configuration was first developed during World War II by Richard Vogt and George Haag at Blohm & Voss . The Skoda-Kauba SL6 tested the proposed control system in 1944 and, following several design proposals, an order was received for the Blohm & Voss P 215 just weeks before the war ended. The outboard tail reappeared on the Scaled Composites SpaceShipOne in 2003 and SpaceShipTwo in 2010. A tailless aircraft (often tail-less ) traditionally has all its horizontal control surfaces on its main wing surface. It has no horizontal stabiliser  – either tailplane or canard foreplane (nor does it have

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