TABSO Flight 101
Encyclopedia
TABSO Flight LZ101 was a scheduled service of the Bulgarian national airline from Sofia
, Bulgaria
via Budapest
, Hungary
and Prague
, Czechoslovakia
(today's Czech Republic
) to East Berlin
in the German Democratic Republic
(today's Germany
). The service was operated by the airline's 1960s' flagship equipment, the Ilyushin
Il-18B
airliner
. On Thursday 24 November 1966, the service crashed near Bratislava
, the capital of Slovakia
then part of Czechoslovakia
, with the loss of 82 lives. The crash remains Slovakia's worst air disaster.
The crew comprised Commander (captain) Lubomir Todorov Antonov, 41-years-old, with 11,959 total flight hours. He was among TABSO's most senior Il-18 commanders, having gained command of the type in July 1962, a month or so after its inauguration
into his airline's service. Antonov had passed a proficiency
test two days earlier. He was very familiar with Bratislava Airport, having operated there on 11 prior occasions. Second Pilot (first officer) was Svetoslav Dimitrov Shakadanov, 36, with 5975 flight hours. He had passed a proficiency check the previous day. Navigator
Officer was First Class Specialist Navigator Slavi Stefanov Tomakov. Radio
-Telegraphy
Officer was Nikola Aleksandrov Tasev, 36-years-old, with 3160 flight hours. On-Board Mechanic
al Officer was Stoyan Todorov Rangelov, 42, with 3602 flight hours. Cabin crew comprised Stewardesses Maria Ivanova, Svetla Georgieva (also known as Svetla Marinova, married 18 days earlier to Ivan Slavkov
) and Violina Stoichkova.
The 74 passengers on board Flight LZ101 were of 12 nationalities: Bulgarians, Argentinians, Britons, Chileans, Czechslovaks, Germans, Hondurans, Hungarians, Japanese, Soviets, Swiss and Tunisians. Among them were Bulgarian opera soloist Katya Popova, Bulgaria's ambassador to the German Democratic Republic
, General Ivan Buchvarov and famous Honduran
writer and journalist Ramón Amaya Amador
. The diversity of nationalities was partly explained by the recent Ninth Congress of the BKP Bulgarian Communist Party, many of them having been delegated to it by foreign communist parties.
Flight LZ101 departed Budapest at 1146 hours CET
. While it was en-route, weather
in Prague deteriorated. Commander Antonov elected to make a diversion to Bratislava Airport (today the M. R. Štefánik Airport
, landing there at 1158hrs. By 1530 hrs, the weather in Prague had improved and Antonov decided to prepare to resume the flight. Bratislava Airport meteorologist Jan Popeleny briefed the Commander that medium to strong turbulence
was expected above the Little Carpathians
hills north-west of Bratislava.
By 1610 the flight had boarded and at 16:20:30 hrs, Antonov was given clearance to taxi to Runway 04 or Runway 31 at his discretion. (He chose to use Runway 31 whose extended centreline crossed the Little Carpathians.) At the same time, he was cleared to take off, to turn right, to overfly the Nitra
radio beacon and to proceed to overhead Brno
and on to Prague at 5100m/16700 ft. Meanwhile, an Il-14
airliner of Czechoslovak Airlines had taken off from Bratislava. In order to maintain separation between the slower Il-14 and his faster Il-18, Antonov was instructed to maintain a height
of 300m/1000 ft until cleared to climb to his cruise
altitude
.
Flight LZ101 took off at 16:28 hrs in almost total darkness. Its departure was observed by air traffic controller Jaroslav Vadovic who reported that it had been normal. Shortly after reporting lift-off, LZ101 was instructed to turn right and contact the Bratislava Approach controller on a frequency of 120.9 MHz. The airliner failed to make the transition to Approach control. Some two minutes after departing Bratislava Airport, it crashed
8 kilometres (5 mi) from the airport into the Sakrakopec location in the foothills of the Little Carpathians
, near Bratislava's borough of Rača
. The area of impact was 288m/945 ft above the elevation of the airport. The aircraft struck the snow-covered ground while flying without any bank angle, at a speed of some 500 km/h/250 knots and while full take-off power was delivered by its engines. As it disintegrated over a period of 20 seconds, it left a swathe with a total length of 562 m and a width of between 30 m and 10 m, of which the main wreckage was located towards the end of a 265 m strip. A fierce fuel fire broke out but burned out fairly rapidly, mostly because fragments and fuel had dispersed over a large area.
The location of the crash was close to built-up areas of Bratislava and very popular with hikers. The accident was observed and heard by many local residents, including an off-duty air traffic controller who immediately telephoned his colleagues at the airport. The approach controllers at the airport had not, however, observed the accident, visually or on radar
.
Because of difficult terrain, total darkness and poor weather, rescue services failed to find the scene of the crash for an hour and a half after being summoned. More delays and hesitation were caused by fears that the airliner might have been carrying radioactive isotope
s. Within the next three days, the bodies of 74 of the 82 souls on board were recovered and transported to Bratislava for identification. Most victims had died instantly due to multiple injuries received during the impact, and most had severe burn marks sustained post-mortem.
Today, a timber cross marks the site where the aircraft's flightdeck came to a rest and 82 birch
trees (one for each victim) mark the general location of the wreckage.
The investigators documented that the local militia (police), Czechoslovak State Security and Bratislava Military Engineer School ranks searched an area of some 350m by 50m (1000 ft by 150 ft) surrounding the accident site. This involved removing snow cover of between 30 and 50 cm (12 to 20 in). The fears that the airliner was carrying radioactive isotopes were confirmed on 8 December 1966 when it was stated that it comprised two steel-lead containers with Iodine-131 for medical purposes. This isotope is, in fact, entirely harmless to human health and permitted for carriage on commercial flights under international law. The airliner's altimeter was found to indicate the correct height above Bratislava airport.
Extreme and escalating tension between the Bulgarian and Czechoslovak authorities and accident investigators was apparent from the outset. An advance TABSO party led by Beluhov had arrived at Bratislava the day after the crash but had been denied any access to the accident site or to any air traffic controllers. The Bulgarian side believed that air traffic controllers in the local Tower and Approach sectors had neglected their duties in allowing a slower aircraft (the Il-14) to depart before a high-performance aircraft (the Il-18), in failing to clear flight LZ101 to a safe height, and in failing to monitor its progress on radar. The Czechoslovak side believed that the flight crew had demonstrated poor comprehension of English by failing to turn right after lift-off, as instructed. The Czechoslovaks were also accused by the Bulgarians of spreading rumours that LZ101's flight crew had consumed alcohol while waiting in Bratislava. Dr Peychev insisted that a test recently developed by NASA
be conducted on tissues taken from the Commander and Second Pilot; the results showed that they had not consumed alcohol.
Ultimately, Czechoslovak Minister of Transport Alois Indra assumed overall control of the investigation in order to resolve the conflict between the Bulgarian and Czechoslovak sides. The issues in the conflict touched national prestige and the amount of damages payable to the victims' families: if Czechoslovak air traffic control was found deficient, they would receive 20,000 US dollars each. If the Bulgarian crew was found deficient, they would receive 10,000 leva each.
The Czechoslovak commission's eventual report stated that departure from runway 31 followed by climb to 300 m/1000 ft was possible without colliding with obstacles. While the stipulated height of 300 metres was adhered to, the aircraft departed from the route which would have kept it clear of ground obstacles. This deviation may have been caused by a wider than necessary turn, greater speed, or a combination of both. It was not possible to exclude the possibility that the crew may have doubted the correct operation of their artificial horizon. It was also not possible to exclude the effect of turbulence on maintaining a uniform bank angle in the turn. The crew, however, had sufficient warning of the weather. The situation became critical when the crew failed to execute the stipulated and acknowledged departure manoeuvre and when unpredictable circumstances may have arisen and accrued during the turn. The report concluded that the cause of the accident could not be determined clearly from the established facts. The most likely cause was inadequate evaluation of terrain and weather by the crew, leading them to fly in a manner inappropriate to these conditions.
, it had a massive public resonance in Bulgaria. The remains of the Bulgarian victims were ceremonially returned to Sofia and interred in the city's main cemetery, and all traffic was brought to a two-minute standstill when air-raid sirens sounded throughout Bulgaria. Poet Pavel Matev
wrote the valedictory
poem Ti san li si? ("Are you but a dream?") to Katya Popova which singer Lili Ivanova
turned into a remorseful popular hit.
in order to eliminate Gen Buchvarov. The topic rapidly became the subject of insistent dark rumours at the time. It was revived after the fall of Zhivkov. No evidence has been found to confirm or deny this.
Sofia
Sofia is the capital and largest city of Bulgaria and the 12th largest city in the European Union with a population of 1.27 million people. It is located in western Bulgaria, at the foot of Mount Vitosha and approximately at the centre of the Balkan Peninsula.Prehistoric settlements were excavated...
, Bulgaria
Bulgaria
Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...
via Budapest
Budapest
Budapest is the capital of Hungary. As the largest city of Hungary, it is the country's principal political, cultural, commercial, industrial, and transportation centre. In 2011, Budapest had 1,733,685 inhabitants, down from its 1989 peak of 2,113,645 due to suburbanization. The Budapest Commuter...
, Hungary
Hungary
Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...
and 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...
, 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...
(today's Czech Republic
Czech Republic
The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....
) to East Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
in the German Democratic Republic
German Democratic Republic
The German Democratic Republic , informally called East Germany by West Germany and other countries, was a socialist state established in 1949 in the Soviet zone of occupied Germany, including East Berlin of the Allied-occupied capital city...
(today's Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
). The service was operated by the airline's 1960s' flagship equipment, the Ilyushin
Ilyushin
Open Joint Stock Company «Ilyushin Aviation Complex» , operating as Ilyushin or Ilyushin Design Bureau, is a Russian design bureau and aircraft manufacturer, founded by Sergey Vladimirovich Ilyushin. Ilyushin was established under the Soviet Union. Its operations began on January 13, 1933, by...
Il-18B
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...
airliner
Airliner
An airliner is a large fixed-wing aircraft for transporting passengers and cargo. Such aircraft are operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an aircraft intended for carrying multiple passengers in commercial...
. On Thursday 24 November 1966, the service crashed near Bratislava
Bratislava
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...
, the capital of Slovakia
Slovakia
The Slovak Republic is a landlocked state in Central Europe. It has a population of over five million and an area of about . Slovakia is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south...
then part of 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...
, with the loss of 82 lives. The crash remains Slovakia's worst air disaster.
Events
On the day of the accident, flight LZ101 was operated by an Il-18B airliner registered LZ-BEN. It had been manufactured in January 1964 (constructor's number 7101) and had been accepted by TABSO on 22 January that year. By the time of the accident, it had not been involved in any incidents and had been maintained in accordance with the manufacturer's schedules.The crew comprised Commander (captain) Lubomir Todorov Antonov, 41-years-old, with 11,959 total flight hours. He was among TABSO's most senior Il-18 commanders, having gained command of the type in July 1962, a month or so after its inauguration
Inauguration
An inauguration is a formal ceremony to mark the beginning of a leader's term of office. An example is the ceremony in which the President of the United States officially takes the oath of office....
into his airline's service. Antonov had passed a proficiency
Proficiency
Proficiency may refer to:* Language proficiency, the ability of an individual to speak or perform in an acquired language* Expertise* Skill, the learned capacity to carry out pre-determined results often with the minimum outlay of time, energy, or both...
test two days earlier. He was very familiar with Bratislava Airport, having operated there on 11 prior occasions. Second Pilot (first officer) was Svetoslav Dimitrov Shakadanov, 36, with 5975 flight hours. He had passed a proficiency check the previous day. Navigator
Navigator
A navigator is the person on board a ship or aircraft responsible for its navigation. The navigator's primary responsibility is to be aware of ship or aircraft position at all times. Responsibilities include planning the journey, advising the Captain or aircraft Commander of estimated timing to...
Officer was First Class Specialist Navigator Slavi Stefanov Tomakov. Radio
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
-Telegraphy
Telegraphy
Telegraphy is the long-distance transmission of messages via some form of signalling technology. Telegraphy requires messages to be converted to a code which is known to both sender and receiver...
Officer was Nikola Aleksandrov Tasev, 36-years-old, with 3160 flight hours. On-Board Mechanic
Mechanics
Mechanics is the branch of physics concerned with the behavior of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment....
al Officer was Stoyan Todorov Rangelov, 42, with 3602 flight hours. Cabin crew comprised Stewardesses Maria Ivanova, Svetla Georgieva (also known as Svetla Marinova, married 18 days earlier to Ivan Slavkov
Ivan Slavkov
Ivan Slavkov was a Bulgarian sports boss linked to the Communist-era nomenklatura. He served as the President of the Bulgarian Olympic Committee between 1982 and 2005 and was a member of the International Olympic Committee between 1987 and 2005.During the Communist regime in Bulgaria, Slavkov...
) and Violina Stoichkova.
The 74 passengers on board Flight LZ101 were of 12 nationalities: Bulgarians, Argentinians, Britons, Chileans, Czechslovaks, Germans, Hondurans, Hungarians, Japanese, Soviets, Swiss and Tunisians. Among them were Bulgarian opera soloist Katya Popova, Bulgaria's ambassador to the German Democratic Republic
German Democratic Republic
The German Democratic Republic , informally called East Germany by West Germany and other countries, was a socialist state established in 1949 in the Soviet zone of occupied Germany, including East Berlin of the Allied-occupied capital city...
, General Ivan Buchvarov and famous Honduran
Honduras
Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...
writer and journalist Ramón Amaya Amador
Ramón Amaya Amador
-Biography:Amaya was born in Olanchito in the department of Yoro. After being educated in La Ceiba he worked on the banana plantations along the Northern Caribbean coast of Honduras. He published his first work in 1939. He became a journalist in 1941 for El Atlántico , a La Ceiba newspaper. In...
. The diversity of nationalities was partly explained by the recent Ninth Congress of the BKP Bulgarian Communist Party, many of them having been delegated to it by foreign communist parties.
Flight LZ101 departed Budapest at 1146 hours CET
Central European Time
Central European Time , used in most parts of the European Union, is a standard time that is 1 hour ahead of Coordinated Universal Time . The time offset from UTC can be written as +01:00...
. While it was en-route, weather
Weather
Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy. Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate...
in Prague deteriorated. Commander Antonov elected to make a diversion to Bratislava Airport (today the M. R. Štefánik 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...
, landing there at 1158hrs. By 1530 hrs, the weather in Prague had improved and Antonov decided to prepare to resume the flight. Bratislava Airport meteorologist Jan Popeleny briefed the Commander that medium to strong turbulence
Turbulence
In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by chaotic and stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time...
was expected above the Little Carpathians
Little Carpathians
The Little Carpathians are a low, about 100 km long, mountain range, part of the Carpathian Mountains. The mountains are situated in Western Slovakia, covering the area from Bratislava to Nové Mesto nad Váhom, a very small part called Hundsheimer Berge is situated south of Devín Gate in...
hills north-west of Bratislava.
By 1610 the flight had boarded and at 16:20:30 hrs, Antonov was given clearance to taxi to Runway 04 or Runway 31 at his discretion. (He chose to use Runway 31 whose extended centreline crossed the Little Carpathians.) At the same time, he was cleared to take off, to turn right, to overfly the Nitra
Nitra
Nitra is a city in western Slovakia, situated at the foot of Zobor Mountain in the valley of the river Nitra. With a population of about 83,572, it is the fifth largest city in Slovakia. Nitra is also one of the oldest cities in Slovakia and the country's earliest political and cultural center...
radio beacon and to proceed to overhead Brno
Brno
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...
and on to Prague at 5100m/16700 ft. Meanwhile, an Il-14
Il-14
IL-14 can refer to:*Ilyushin Il-14, a Soviet twin-engine aircraft*Interleukin 14, a protein important in immunology*Illinois's 14th congressional district*Illinois Route 14...
airliner of Czechoslovak Airlines had taken off from Bratislava. In order to maintain separation between the slower Il-14 and his faster Il-18, Antonov was instructed to maintain a height
Height
Height is the measurement of vertical distance, but has two meanings in common use. It can either indicate how "tall" something is, or how "high up" it is. For example "The height of the building is 50 m" or "The height of the airplane is 10,000 m"...
of 300m/1000 ft until cleared to climb to his cruise
Cruise (flight)
Cruise is the level portion of aircraft travel where flight is most fuel efficient. It occurs between ascent and descent phases and is usually the majority of a journey. Technically, cruising consists of heading changes only at a constant airspeed and altitude...
altitude
Altitude
Altitude or height is defined based on the context in which it is used . As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context...
.
Flight LZ101 took off at 16:28 hrs in almost total darkness. Its departure was observed by air traffic controller Jaroslav Vadovic who reported that it had been normal. Shortly after reporting lift-off, LZ101 was instructed to turn right and contact the Bratislava Approach controller on a frequency of 120.9 MHz. The airliner failed to make the transition to Approach control. Some two minutes after departing Bratislava Airport, it crashed
Aviation accidents and incidents
An aviation accident is defined in the Convention on International Civil Aviation Annex 13 as an occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of flight and all such persons have disembarked, in which a...
8 kilometres (5 mi) from the airport into the Sakrakopec location in the foothills of the Little Carpathians
Little Carpathians
The Little Carpathians are a low, about 100 km long, mountain range, part of the Carpathian Mountains. The mountains are situated in Western Slovakia, covering the area from Bratislava to Nové Mesto nad Váhom, a very small part called Hundsheimer Berge is situated south of Devín Gate in...
, near Bratislava's borough of Rača
Raca
Raca or RACA can refer to:* Raca, a Biblical term of Aramaic origin used in Matthew 5:22. See Aramaic of Jesus or Expounding of the Law.* Rača, a town and municipality in Serbia* Rača , river in Serbia...
. The area of impact was 288m/945 ft above the elevation of the airport. The aircraft struck the snow-covered ground while flying without any bank angle, at a speed of some 500 km/h/250 knots and while full take-off power was delivered by its engines. As it disintegrated over a period of 20 seconds, it left a swathe with a total length of 562 m and a width of between 30 m and 10 m, of which the main wreckage was located towards the end of a 265 m strip. A fierce fuel fire broke out but burned out fairly rapidly, mostly because fragments and fuel had dispersed over a large area.
The location of the crash was close to built-up areas of Bratislava and very popular with hikers. The accident was observed and heard by many local residents, including an off-duty air traffic controller who immediately telephoned his colleagues at the airport. The approach controllers at the airport had not, however, observed the accident, visually or on radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
.
Because of difficult terrain, total darkness and poor weather, rescue services failed to find the scene of the crash for an hour and a half after being summoned. More delays and hesitation were caused by fears that the airliner might have been carrying radioactive isotope
Isotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
s. Within the next three days, the bodies of 74 of the 82 souls on board were recovered and transported to Bratislava for identification. Most victims had died instantly due to multiple injuries received during the impact, and most had severe burn marks sustained post-mortem.
Today, a timber cross marks the site where the aircraft's flightdeck came to a rest and 82 birch
Birch
Birch is a tree or shrub of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae. The Betula genus contains 30–60 known taxa...
trees (one for each victim) mark the general location of the wreckage.
Investigation
The investigation was conducted by a Czechoslovak commission headed by Chief Inspector of Aeronautics Jan Dvorak. Under international law, he coopted representatives of the country in which the aircraft was registered and representatives of the Ilyushin design bureau and the Ivchenko engine design bureau. A Bulgarian commission of enquiry was also formed, headed by State Comptrol Commission Chairman and BKP Bulgarian Communist Party Central Committee member Ninko Stefanov) and also included TABSO Director General Lazar Beluhov, air specialist and deputy defence minisgter Gen Avgust Kabakchiev and Darzhavna Sigurnost (State Security) investigator Col Ivan Ohridski, chief police pathologist Dr Yordan Peychev and enough others to fill two specially chartered aircraft. The Bulgarians requested to lead the inquiry under a provision in international law which allowed this. The Czechoslovak authorities refused this on the grounds of reciprocity: Bulgaria had not signed the clause allowing foreign investigators to inquire into crashes in Bulgaria.The investigators documented that the local militia (police), Czechoslovak State Security and Bratislava Military Engineer School ranks searched an area of some 350m by 50m (1000 ft by 150 ft) surrounding the accident site. This involved removing snow cover of between 30 and 50 cm (12 to 20 in). The fears that the airliner was carrying radioactive isotopes were confirmed on 8 December 1966 when it was stated that it comprised two steel-lead containers with Iodine-131 for medical purposes. This isotope is, in fact, entirely harmless to human health and permitted for carriage on commercial flights under international law. The airliner's altimeter was found to indicate the correct height above Bratislava airport.
Extreme and escalating tension between the Bulgarian and Czechoslovak authorities and accident investigators was apparent from the outset. An advance TABSO party led by Beluhov had arrived at Bratislava the day after the crash but had been denied any access to the accident site or to any air traffic controllers. The Bulgarian side believed that air traffic controllers in the local Tower and Approach sectors had neglected their duties in allowing a slower aircraft (the Il-14) to depart before a high-performance aircraft (the Il-18), in failing to clear flight LZ101 to a safe height, and in failing to monitor its progress on radar. The Czechoslovak side believed that the flight crew had demonstrated poor comprehension of English by failing to turn right after lift-off, as instructed. The Czechoslovaks were also accused by the Bulgarians of spreading rumours that LZ101's flight crew had consumed alcohol while waiting in Bratislava. Dr Peychev insisted that a test recently developed by NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
be conducted on tissues taken from the Commander and Second Pilot; the results showed that they had not consumed alcohol.
Ultimately, Czechoslovak Minister of Transport Alois Indra assumed overall control of the investigation in order to resolve the conflict between the Bulgarian and Czechoslovak sides. The issues in the conflict touched national prestige and the amount of damages payable to the victims' families: if Czechoslovak air traffic control was found deficient, they would receive 20,000 US dollars each. If the Bulgarian crew was found deficient, they would receive 10,000 leva each.
The Czechoslovak commission's eventual report stated that departure from runway 31 followed by climb to 300 m/1000 ft was possible without colliding with obstacles. While the stipulated height of 300 metres was adhered to, the aircraft departed from the route which would have kept it clear of ground obstacles. This deviation may have been caused by a wider than necessary turn, greater speed, or a combination of both. It was not possible to exclude the possibility that the crew may have doubted the correct operation of their artificial horizon. It was also not possible to exclude the effect of turbulence on maintaining a uniform bank angle in the turn. The crew, however, had sufficient warning of the weather. The situation became critical when the crew failed to execute the stipulated and acknowledged departure manoeuvre and when unpredictable circumstances may have arisen and accrued during the turn. The report concluded that the cause of the accident could not be determined clearly from the established facts. The most likely cause was inadequate evaluation of terrain and weather by the crew, leading them to fly in a manner inappropriate to these conditions.
In popular culture
The accident was the second one to befall TABSO since 1952 and the airline's first publicly acknowledged one. Largely because of the loss of Katya Popova, well known Bulgarian lyric sopranoSoprano
A soprano is a voice type with a vocal range from approximately middle C to "high A" in choral music, or to "soprano C" or higher in operatic music. In four-part chorale style harmony, the soprano takes the highest part, which usually encompasses the melody...
, it had a massive public resonance in Bulgaria. The remains of the Bulgarian victims were ceremonially returned to Sofia and interred in the city's main cemetery, and all traffic was brought to a two-minute standstill when air-raid sirens sounded throughout Bulgaria. Poet Pavel Matev
Pavel Matev
Pavel Hristov Matev was a Bulgarian poet.Matev was born in the village of Orisovo, in the Stara Zagora province, , and completed his gymnasium education in the town of Tsirpan in 1938. His first work was published in 1946. He completed a course in Slavic studies in Sofia University in 1949...
wrote the valedictory
Valediction
A valediction , or complimentary close in American English, is an expression used to say farewell, especially a word or phrase used to end a letter or message, or the act of saying parting words- whether brief, or extensive.For the greetings counterpart to valediction, see salutation.Alternatively,...
poem Ti san li si? ("Are you but a dream?") to Katya Popova which singer Lili Ivanova
Lili Ivanova
Lili Ivanova is a popular Bulgarian singer.-Discography:Lili Ivanova has released 65 albums Lili Ivanova (born April 24, 1939 in Kubrat) is a popular Bulgarian singer.-Discography:Lili Ivanova has released 65 albums Lili Ivanova (born April 24, 1939 in Kubrat) is a popular Bulgarian...
turned into a remorseful popular hit.
Ivan Buchvarov conspiracy theory
One of the accident investigators appointed by the Bulgarian side, Supreme Court investigating magistrate Nedyu Ganchev, committed suicide during the closing stages of the investigation. Shortly beforehand, he had said to friends, "I cannot do what they insist I should do." This led some Bulgarians to believe that the crash may have been staged by Todor ZhivkovTodor Zhivkov
Todor Khristov Zhivkov was a communist politician and leader of the People's Republic of Bulgaria from March 4, 1954 until November 10, 1989....
in order to eliminate Gen Buchvarov. The topic rapidly became the subject of insistent dark rumours at the time. It was revived after the fall of Zhivkov. No evidence has been found to confirm or deny this.