CSA Flight OK-NAB
Encyclopedia
ČSA flight 001 registration OK-NAB was an Ilyushin Il-18
B 4 engine turboprop
, operating as a scheduled domestic passenger flight from Prague
's Ruzyně
airport to Bratislava-Ivanka Airport
, both in Czechoslovakia
, which crashed into the Zlaté Piesky
(Golden Sands) Lake while attempting to land in Bratislava on July 28, 1976. All 6 crew members and 70 out of 73 passengers died.
tower to land on runway 22. For reasons that are unclear, the crew executed a highly unstabilized ILS
instrument approach
to runway 22, with rates of descent as high as 22m/s (72 ft/sec) instead of 10m/s (33 ft/sec); speeds varying from 435km/h (270 mph) to 225 km/h (140 mph) instead of 269 km/h (167 mph); and flap selection directly from 0 degree to full flaps instead of in gradual increments. As they approached the runway, the crew inadvertently set thrust reversal at the no. 2 and no. 3 engine (inboard engines) while still airborne. The thrust reversal caused the no. 3 engine to fail and the crew then inadvertently feathered the no. 4 prop, losing all thrust on the right side of the aircraft. At 50m (164 ft) above the runway threshold the crew attempted to execute a go around. They tried to restart the no. 4 engine at 40m (131 ft), but the ensuing right bank due to asymmetric thrust increased; the aircraft then lost control and struck lake Zlaté piesky
(Golden Sands) in a 60 degree right bank and a 60 degree nose down attitude.
divers tried to help, but most passengers drowned or died due to crash forces. Initially four passengers were pulled out alive, of whom two later died in the hospital.
but it was rejected because of the Vietnamese delegation visiting the city and an emergency landing would harm the image of the country. He also claimed that Vienna airport
offered an emergency landing permission but communist
authorities rejected it. It is unclear how a surviving passenger would be aware of the captain's actions during the flight, or how searching for an alternate emergency landing site relates to an unstablilized approach with inadvertent thrust reversal deployment at Bratislava.
Ilyushin Il-18
The Ilyushin Il-18 is a large turboprop airliner that became one of the best known Soviet aircraft of its era as well as one of the most popular and durable, having first flown in 1957 and still in use over 50 years later. The Il-18 was one of the world's principal airliners for several decades...
B 4 engine turboprop
Turboprop
A turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...
, operating as a scheduled domestic passenger flight from Prague
Prague
Prague is the capital and largest city of the Czech Republic. Situated in the north-west of the country on the Vltava river, the city is home to about 1.3 million people, while its metropolitan area is estimated to have a population of over 2.3 million...
's Ruzyně
Ruzyne International Airport
-Ruzyně today:Most flights depart Ruzyně Airport from the North Terminals . The South Terminals handle a few irregular flights, as well as VIP flights, special flights and small aircraft....
airport to Bratislava-Ivanka Airport
M. R. Štefánik Airport
-Cargo airlines:-Charter airlines:winter 2011/12 list-VIP and other operators:*ABS Jets – base*Tatra Jet – focus city*OPERA JET – base*VR Jet – base...
, both in Czechoslovakia
Czechoslovakia
Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992...
, which crashed into the Zlaté Piesky
Zlaté Piesky
Zlaté Piesky is a lake and a summer resort in northeastern Bratislava, Slovakia, near the D1 motorway.-Characteristics:...
(Golden Sands) Lake while attempting to land in Bratislava on July 28, 1976. All 6 crew members and 70 out of 73 passengers died.
Crash
The flight departed Prague airport at 8:52 (CEST) and proceeded routinely to Bratislava. At 9:35:10 (CEST) the flight was cleared by BratislavaBratislava
Bratislava is the capital of Slovakia and, with a population of about 431,000, also the country's largest city. Bratislava is in southwestern Slovakia on both banks of the Danube River. Bordering Austria and Hungary, it is the only national capital that borders two independent countries.Bratislava...
tower to land on runway 22. For reasons that are unclear, the crew executed a highly unstabilized ILS
Instrument Landing System
An instrument landing system is a ground-based instrument approach system that provides precision guidance to an aircraft approaching and landing on a runway, using a combination of radio signals and, in many cases, high-intensity lighting arrays to enable a safe landing during instrument...
instrument approach
Instrument approach
For aircraft operating under instrument flight rules , an instrument approach or instrument approach procedure is a series of predetermined maneuvers for the orderly transfer of an aircraft under instrument flight conditions from the beginning of the initial approach to a landing, or to a point...
to runway 22, with rates of descent as high as 22m/s (72 ft/sec) instead of 10m/s (33 ft/sec); speeds varying from 435km/h (270 mph) to 225 km/h (140 mph) instead of 269 km/h (167 mph); and flap selection directly from 0 degree to full flaps instead of in gradual increments. As they approached the runway, the crew inadvertently set thrust reversal at the no. 2 and no. 3 engine (inboard engines) while still airborne. The thrust reversal caused the no. 3 engine to fail and the crew then inadvertently feathered the no. 4 prop, losing all thrust on the right side of the aircraft. At 50m (164 ft) above the runway threshold the crew attempted to execute a go around. They tried to restart the no. 4 engine at 40m (131 ft), but the ensuing right bank due to asymmetric thrust increased; the aircraft then lost control and struck lake Zlaté piesky
Zlaté Piesky
Zlaté Piesky is a lake and a summer resort in northeastern Bratislava, Slovakia, near the D1 motorway.-Characteristics:...
(Golden Sands) in a 60 degree right bank and a 60 degree nose down attitude.
Investigation
The investigators published the causes as follows:- Use of thrust reversal at altitude under 1 000 m (3280 feet)
- Improper manipulation of the thrust levers of the inner engines
- Reducing speed under the allowed limit on final approach
- Erroneous feathering of the engine number 4 propeller
- Failure to bank the plane towards the working engines side
- The immediate cause was the attempt to start engine number 4 at low speed and altitude
Rescue operation
The plane crashed into a lake in a densely populated area and rescue operations started immediately after the crash. SvazarmSVAZARM
Svazarm or Union for Cooperation with the Army , was, in Communist Czechoslovakia, the largest "paramilitary" organisation, though in fact many of the activities that Svazarm provided for its members were more reminiscent of a Boy Scout movement than of a...
divers tried to help, but most passengers drowned or died due to crash forces. Initially four passengers were pulled out alive, of whom two later died in the hospital.
Controversy
Surviving passenger Jaromír Kratochvíl later claimed in an interview that flight captain requested emergency landing in BrnoBrno
Brno by population and area is the second largest city in the Czech Republic, the largest Moravian city, and the historical capital city of the Margraviate of Moravia. Brno is the administrative centre of the South Moravian Region where it forms a separate district Brno-City District...
but it was rejected because of the Vietnamese delegation visiting the city and an emergency landing would harm the image of the country. He also claimed that Vienna airport
Vienna International Airport
Vienna International Airport , located in Schwechat and southeast of central Vienna, is the busiest and biggest airport in Austria. It is often referred to as Schwechat, the name of the county it is in. The airport is capable of handling wide-body aircraft such as the Boeing 747 and Airbus A340...
offered an emergency landing permission but communist
Communism
Communism is a social, political and economic ideology that aims at the establishment of a classless, moneyless, revolutionary and stateless socialist society structured upon common ownership of the means of production...
authorities rejected it. It is unclear how a surviving passenger would be aware of the captain's actions during the flight, or how searching for an alternate emergency landing site relates to an unstablilized approach with inadvertent thrust reversal deployment at Bratislava.
See also
- List of notable accidents and incidents on commercial aircraft
- TABSO Flight 101TABSO Flight 101TABSO Flight LZ101 was a scheduled service of the Bulgarian national airline from Sofia, Bulgaria via Budapest, Hungary and Prague, Czechoslovakia to East Berlin in the German Democratic Republic . The service was operated by the airline's 1960s' flagship equipment, the Ilyushin Il-18B airliner...
- Ilyushin Il-18B crash at Bratislava in 1966