Austral Líneas Aéreas Flight 2553
Encyclopedia
Austral Líneas Aéreas
Flight 2553, better known as Austral 2553, was a domestic scheduled Posadas
–Buenos Aires
service operated with a McDonnell Douglas DC-9-32 that crashed on the lands of Estancia Magallanes, Nuevo Berlín
, 32 kilometres (19.9 mi) away from Fray Bentos
, Uruguay
, on . All 74 passengers and crew perished after the impact. The accident remains the deadliest one both in the Uruguay
an, and in the Argentine
aviation history.
with registration EC-BQT, and it was transferred to Austral after the buyout of the company by the Spanish carrier.
and was due to land in Aeroparque Jorge Newbery
, Buenos Aires
, was forced to divert towards Fray Bentos to avoid a storm. Examination of the aircraft's flight data recorder
(FDR) revealed that shortly after the diversion occurred, the aircraft airspeed
began to fall to an alarmingly low airspeed. In response, the pilots repeatedly increased power from the engines in order to maintain airspeed; seeing no improvement, they contacted the control tower in Ezeiza Airport
and requested clearance to descend to a lower altitude. After receiving no response, the pilots lowered the aircraft's wing slats
to maintain their altitude and lower the plane's stall speed. When lowering the slats however, one of them was torn from the aircraft, causing catastrophic asymmetry in the air flow over the wings. The aircraft immediately became uncontrollable and crashed.
According to an investigation by both the Argentine
and Uruguayan Air Force
s, the pitot tube
—the primary instrument for measuring aircraft airspeeds—froze when the aircraft passed through a 15000 m high cumulonimbus cloud, blocking the instrument and causing it to give a false reading. Compounding this problem was the failure of the alarm designed to report such a malfunction (raising serious questions about inspection irregularities by the Argentine Air Force).
Thinking that the aircraft was flying at a dangerous low speed, the pilots increased power to the engines and then deployed the slats. Far from flying at the low speed reported by the instruments, the aircraft was actually exceeding its safe cruising speed, and far above a safe speed for deploying slats. During the deployment of the slats, one was torn off by the force of the high speed airflow traveling over the wing, which caused the aircraft to become unflyable and enter a steep descent.
During the descent, the FDR recorded an increase in the airspeed from 300 to 800 km/h in three seconds, which could only signify the sudden unfreezing of the pitot tube. Specialists estimated that the aircraft crashed almost perpendicularly to the ground, at a speed of 1200 km/h. Depending upon the source, the crater
left by the crash was 6 m (19.7 ft) deep and 30 m (98.4 ft) wide, 25 ft (7.6 m) and 30 ft (9.1 m), or 25 ft (7.6 m) deep and 80 ft (24.4 m) wide.
Austral Líneas Aéreas
Austral Líneas Aéreas , more commonly known by its shortened name Austral, is a domestic airline of Argentina, the sister company of Aerolíneas Argentinas. It is the second largest domestic scheduled airline in the country, after Aerolíneas Argentinas itself...
Flight 2553, better known as Austral 2553, was a domestic scheduled Posadas
Posadas, Misiones
Posadas is the capital city of the Argentine province of Misiones, located at the south of the province, on the left-hand shore of the Paraná River, opposite Encarnación, Paraguay. The city has an area of 965 km² and a population of 323,739 ....
–Buenos Aires
Buenos Aires
Buenos Aires is the capital and largest city of Argentina, and the second-largest metropolitan area in South America, after São Paulo. It is located on the western shore of the estuary of the Río de la Plata, on the southeastern coast of the South American continent...
service operated with a McDonnell Douglas DC-9-32 that crashed on the lands of Estancia Magallanes, Nuevo Berlín
Nuevo Berlín
Nuevo Berlín is a town in the Río Negro Department of western Uruguay. It is located on the east bank of Uruguay River northwest of the junction of Route 24 with Route 20. South of the town flows the stream Arroyo de la Yeguada and to its west, in the Uruguay River, is the island Isla del Burro...
, 32 kilometres (19.9 mi) away from Fray Bentos
Fray Bentos
Fray Bentos, the capital of the Río Negro Department of western Uruguay, is a port on the Uruguay River. It is close to the border with Argentina and about due north of Buenos Aires.-History:...
, Uruguay
Uruguay
Uruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area...
, on . All 74 passengers and crew perished after the impact. The accident remains the deadliest one both in the Uruguay
Uruguay
Uruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area...
an, and in the Argentine
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
aviation history.
Aircraft
The aircraft involved in the accident was a McDonnell Douglas DC-9-32, registration LV-WEG. It had its maiden flight in 1969, and was 28 years old at the time of the accident. It had previously operated for IberiaIberia Airlines
Iberia Líneas Aéreas de España, S.A., commonly known as Iberia, is the flag carrier airline of Spain. Based in Madrid, it operates an international network of services from its main bases of Madrid-Barajas Airport and Barcelona El Prat Airport....
with registration EC-BQT, and it was transferred to Austral after the buyout of the company by the Spanish carrier.
Accident
The aircraft, which left from PosadasPosadas, Misiones
Posadas is the capital city of the Argentine province of Misiones, located at the south of the province, on the left-hand shore of the Paraná River, opposite Encarnación, Paraguay. The city has an area of 965 km² and a population of 323,739 ....
and was due to land in Aeroparque Jorge Newbery
Aeroparque Jorge Newbery
-Accidents and incidents:*On 17 December 1969, an Austral Líneas Aéreas C-46 Commando, lost engine 1 due to fuel exhaustion shortly after take-off. The plane failed to gain height and made a crash landing in a small sport field...
, Buenos Aires
Buenos Aires
Buenos Aires is the capital and largest city of Argentina, and the second-largest metropolitan area in South America, after São Paulo. It is located on the western shore of the estuary of the Río de la Plata, on the southeastern coast of the South American continent...
, was forced to divert towards Fray Bentos to avoid a storm. Examination of the aircraft's flight data recorder
Flight data recorder
A flight data recorder is an electronic device employed to record any instructions sent to any electronic systems on an aircraft. It is a device used to record specific aircraft performance parameters...
(FDR) revealed that shortly after the diversion occurred, the aircraft airspeed
Airspeed
Airspeed is the speed of an aircraft relative to the air. Among the common conventions for qualifying airspeed are: indicated airspeed , calibrated airspeed , true airspeed , equivalent airspeed and density airspeed....
began to fall to an alarmingly low airspeed. In response, the pilots repeatedly increased power from the engines in order to maintain airspeed; seeing no improvement, they contacted the control tower in Ezeiza Airport
Ministro Pistarini International Airport
Ministro Pistarini International Airport , more commonly known as Ezeiza International Airport owing to its location within the Ezeiza Partido in the Greater Buenos Aires, is an international airport located south-southwest of Buenos Aires, the capital city of Argentina...
and requested clearance to descend to a lower altitude. After receiving no response, the pilots lowered the aircraft's wing slats
Leading edge slats
Slats are aerodynamic surfaces on the leading edge of the wings of fixed-wing aircraft which, when deployed, allow the wing to operate at a higher angle of attack. A higher coefficient of lift is produced as a result of angle of attack and speed, so by deploying slats an aircraft can fly at slower...
to maintain their altitude and lower the plane's stall speed. When lowering the slats however, one of them was torn from the aircraft, causing catastrophic asymmetry in the air flow over the wings. The aircraft immediately became uncontrollable and crashed.
According to an investigation by both the Argentine
Argentine Air Force
The Argentine Air Force is the national aviation branch of the Armed Forces of the Argentine Republic. , it had 14,606 military and 6,854 civilian staff.-History:...
and Uruguayan Air Force
Uruguayan Air Force
The Uruguayan Air Force is one of the three main branches of the Armed Forces of Uruguay under the Uruguayan Ministry of Defense. The current head of the force is General of the Air Enrique A...
s, the pitot tube
Pitot tube
A pitot tube is a pressure measurement instrument used to measure fluid flow velocity. The pitot tube was invented by the French engineer Henri Pitot Ulo in the early 18th century and was modified to its modern form in the mid-19th century by French scientist Henry Darcy...
—the primary instrument for measuring aircraft airspeeds—froze when the aircraft passed through a 15000 m high cumulonimbus cloud, blocking the instrument and causing it to give a false reading. Compounding this problem was the failure of the alarm designed to report such a malfunction (raising serious questions about inspection irregularities by the Argentine Air Force).
Thinking that the aircraft was flying at a dangerous low speed, the pilots increased power to the engines and then deployed the slats. Far from flying at the low speed reported by the instruments, the aircraft was actually exceeding its safe cruising speed, and far above a safe speed for deploying slats. During the deployment of the slats, one was torn off by the force of the high speed airflow traveling over the wing, which caused the aircraft to become unflyable and enter a steep descent.
During the descent, the FDR recorded an increase in the airspeed from 300 to 800 km/h in three seconds, which could only signify the sudden unfreezing of the pitot tube. Specialists estimated that the aircraft crashed almost perpendicularly to the ground, at a speed of 1200 km/h. Depending upon the source, the crater
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
left by the crash was 6 m (19.7 ft) deep and 30 m (98.4 ft) wide, 25 ft (7.6 m) and 30 ft (9.1 m), or 25 ft (7.6 m) deep and 80 ft (24.4 m) wide.
See also
- Fuerza Aérea Sociedad Anónima, a film by former pilot Enrique PiñeyroEnrique Piñeyro (actor)Enrique Piñeyro is a pilot turned film actor, producer, crash analyst, aeronautical physician, film director, and screenplay writer, working partly in Argentina. Piñeyro and Verónica Cura own Aqua Films, a film production company in Argentina.- Biography :Piñeyro was born in Genoa, Italy, 1956...
that attempts to explain the major causes of the crash - LAPA flight 3142LAPA flight 3142LAPA Flight 3142 was a scheduled Buenos Aires–Córdoba flight operated by the Argentine airline Líneas Aéreas Privadas Argentinas. The service was operated with a Boeing 737-204C, registration LV-WRZ, that crashed on at 20:54 local time while attempting to take off from Aeroparque Jorge Newbery...