A pitot tube measures fluid flow velocity. It was invented by a French engineer, Henri Pitot, in the early 18th century, and was modified to its modern form in the mid-19th century by a French scientist, Henry Darcy. It is widely used to determine the airspeed of aircraft; the water speed of boats; and the flow velocity of liquids, air, and gases in industry.
Delta Air Lines Flight 1141 was a scheduled domestic passenger flight between Dallas/Fort Worth, Texas, and Salt Lake City, Utah. On August 31, 1988, the flight, using a Boeing 727-200 series aircraft, crashed during takeoff, resulting in 14 deaths and 76 injuries among the 108 on board.
A pitot–static system is a system of pressure-sensitive instruments that is most often used in aviation to determine an aircraft's airspeed, Mach number, altitude, and altitude trend. A pitot–static system generally consists of a pitot tube, a static port, and the pitot–static instruments. Other instruments that might be connected are air data computers, flight data recorders, altitude encoders, cabin pressurization controllers, and various airspeed switches. Errors in pitot–static system readings can be extremely dangerous as the information obtained from the pitot static system, such as altitude, is potentially safety-critical. Several commercial airline disasters have been traced to a failure of the pitot–static system.
West Caribbean Airways Flight 708 was a charter flight that crashed in northwest Venezuela in the early hours of Tuesday, 16 August 2005, killing all 160 passengers and crew on board. The plane, a McDonnell Douglas MD-82, registration HK-4374X, was en route from Tocumen International Airport (PTY) in Panama City, Panama, to Martinique Aimé Césaire International Airport (FDF) in Fort-de-France, Martinique, France. While flying at 33,000 ft (10,000 m), the aircraft's speed gradually decreased until it entered an aerodynamic stall. The crew, probably under the mistaken belief that the aircraft had suffered a double engine flameout, did not take the necessary actions to recover from the stall. The confusion and lack of action resulted in the crash.
Trans World Airlines Flight 514, registration N54328, was a Boeing 727-231 en route from Indianapolis, Indiana and Columbus, Ohio to Washington Dulles International that crashed into Mount Weather, Virginia, on December 1, 1974. All 92 people aboard, 85 passengers and seven crew members, were killed. In stormy conditions late in the morning, the aircraft was in controlled flight and impacted a low mountain 25 nautical miles northwest of its revised destination. The accident was one of two crashes involving Boeing 727 aircraft in the United States that day, the other being the crash of Northwest Orient Airlines Flight 6231 later that evening near Haverstraw, New York.
United Airlines Flight 389 was a scheduled flight from LaGuardia Airport, New York City, New York, to O'Hare International Airport, Chicago, Illinois. On August 16, 1965, at approximately 21:21 EST, the Boeing 727 crashed into Lake Michigan 20 miles east of Fort Sheridan, near Lake Forest, while descending from 35,000 feet (11,000 m) mean sea level (MSL). There was no indication of any unusual problem prior to impact. All 30 persons aboard, including six crew members and 24 passengers, were killed.
American Eagle Flight 4184, officially operating as Simmons Airlines Flight 4184, was a scheduled domestic passenger flight from Indianapolis, Indiana, to Chicago, Illinois, United States. On October 31, 1994, the ATR 72 performing this route flew into severe icing conditions, lost control and crashed into a field. All 68 people aboard were killed in the high-speed impact.
Aircraft upset is an unacceptable condition, in aircraft operations, in which the aircraft flight attitude or airspeed is outside the normally intended limits. This may result in the loss of control (LOC) of the aircraft, and sometimes the total loss of the aircraft itself. Loss of control may be due to excessive altitude for the airplane's weight, turbulent weather, pilot disorientation, or a system failure.
Birgenair Flight 301 was a flight chartered by Turkish-managed Birgenair partner Alas Nacionales from Puerto Plata in the Dominican Republic to Frankfurt, Germany, via Gander, Canada, and Berlin, Germany. On 6 February 1996, the Boeing 757-200 operating the route crashed shortly after take-off from Puerto Plata's Gregorio Luperón International Airport. All 189 people on board died. The cause was pilot error after receiving incorrect airspeed information from one of the pitot tubes, which investigators believe was blocked by a wasp nest built inside it. The aircraft had been sitting unused for 20 days, and without pitot tube covers in place for the preceding two days before the crash.
Austral Líneas Aéreas Flight 2553 was an Argentinian domestic scheduled passenger flight from Posadas to Buenos Aires. On October 10, 1997, the McDonnell Douglas DC-9-32 that was operating the flight crashed on the lands of Estancia Magallanes, Nuevo Berlín, 32 kilometres away from Fray Bentos, Uruguay. All 74 passengers and crew died upon impact. The accident remains the deadliest in Uruguayan history.
Alaska Airlines Flight 1866 was a regularly scheduled passenger flight operated by Alaska Airlines from Anchorage, Alaska, to Seattle, Washington, with several intermediate stops in southeast Alaska. The aircraft was a Boeing 727-100 with U.S. registry N2969G manufactured in 1966. On September 4, 1971, the aircraft operating the flight crashed into a mountain in Haines Borough, about 18 miles west of Juneau, Alaska, while on approach for landing. All 111 people aboard were killed. The subsequent investigation found that erroneous navigation readouts led the crew to descend prematurely. No definitive cause for the misleading data was found. It was the first fatal jet aircraft crash involving Alaska Airlines, and remained the deadliest single-aircraft accident in United States history until June 24, 1975, when Eastern Air Lines Flight 66 crashed. It is still, however, the worst air disaster in Alaska state history.
Dan-Air Flight 1008 was a fatal accident involving a Boeing 727-46 jet aircraft operated by Dan Air Services Limited on an unscheduled international passenger service from Manchester to Tenerife. The crash occurred on 25 April 1980 in a forest on Tenerife's Mount La Esperanza when the aircraft's flight deck crew wrongly executed an unpublished holding pattern in an area of very high ground; it resulted in the aircraft's destruction and the deaths of all 146 on board. Flight 1008 was Dan-Air's second major accident in ten years and the worst accident involving the deaths of fare-paying passengers in the airline's entire history.
Air France Flight 447 (AF447/AFR447) was a scheduled international passenger flight from Rio de Janeiro, Brazil, to Paris, France. On 1 June 2009, inconsistent airspeed indications and miscommunication led to the pilots inadvertently stalling the Airbus A330 serving the flight. They failed to recover the plane from the stall, and the plane crashed into the mid-Atlantic Ocean at 02:14 UTC, killing all 228 passengers and crew on board.
Iran Air Flight 277 was a scheduled Iran Air flight from Mehrabad International Airport, Tehran to Urmia Airport, Iran. On January 9, 2011, the Boeing 727 serving the flight crashed after an aborted approach to Urmia Airport in poor weather. Of the 105 people on board, 78 were killed. The official investigation concluded that icing conditions and incorrect engine management by the crew led to a double engine flame-out, loss of altitude and impact with the ground.
United Express Flight 2415 was a regularly scheduled flight in the northwest United States from Seattle to Pasco, Washington, operated using a BAe Jetstream 31. Late on Tuesday, December 26, 1989, Flight 2415 crashed while attempting to land at Pasco's Tri-Cities Airport, killing both pilots and all four passengers aboard.
In aeronautics, loss of control (LOC) is the unintended departure of an aircraft from controlled flight and is a significant factor in several aviation accidents worldwide. In 2015 it was the leading cause of general aviation accidents. Loss of control may be the result of mechanical failure, external disturbances, aircraft upset conditions, or inappropriate crew actions or responses.
Delta Air Lines Flight 723 was a flight operated by a McDonnell Douglas DC-9 twin-engine jetliner, operating as a scheduled domestic passenger flight from Burlington, Vermont, to Logan International Airport in Boston, Massachusetts, with an intermediate stop in Manchester, New Hampshire. On July 31, 1973, at 11:08 a.m., while on an instrument landing system (ILS) instrument approach into Logan in low clouds and fog, the aircraft descended below the glidepath, struck a seawall, and crashed. 88 of the 89 occupants aboard were killed.
Empire Airlines Flight 8284 was a cargo flight operated by Empire Airlines for FedEx Feeder from Fort Worth Alliance Airport to Lubbock Preston Smith International Airport, Texas. On January 27, 2009, it crashed on final approach to its destination. Both crew members survived with minor injuries but the aircraft was written off.
Ryan International Airlines Flight 590 was a cargo flight carrying mail for the United States Postal Service from Greater Buffalo International Airport (BUF) in Buffalo, New York, to Indianapolis International Airport (IND) in Indiana, with a stopover at Cleveland Hopkins International Airport (CLE) in Cleveland, Ohio. On February 17, 1991, the McDonnell Douglas DC-9-15RC operating the flight crashed on takeoff from Cleveland during icing conditions. Both pilots, the aircraft's only occupants, were killed. The National Transportation Safety Board (NTSB) determined that the causes of the crash were the flight crew failing to deice their aircraft, and the inexperience of the Federal Aviation Administration (FAA), McDonnell Douglas, and Ryan International Airlines with icing condition on DC-9-10 aircraft.
