2010 Polish Air Force Tu-154 crash

The 2010 Polish Air Force Tu-154 crash occurred on 10 April 2010, when a Tupolev Tu-154M aircraft of the Polish Air Force crashed near the city of Smolensk, Russia, killing all 96 people on board. These included the Polish president Lech Kaczyński and his wife, former president Ryszard Kaczorowski, the chief of the Polish General Staff and other senior Polish military officers, the president of the National Bank of Poland, Poland's deputy foreign minister, Polish government officials, 15 members of the Polish parliament, senior members of the Polish clergy, and relatives of victims of the Katyn massacre. They were en route from Warsaw to attend an event marking the 70th anniversary of the massacre; the site is approximately 19 kilometres (12 mi) west of Smolensk.

The pilots attempted to land at Smolensk North Airport, a former military airbase, in thick fog that reduced visibility to about 500 metres (1,600 ft). The aircraft was too low as it approached the runway. Striking trees in the fog, it rolled upside down, impacted the ground, broke apart, and eventually came to rest 200 metres (660 ft) short of the runway in a wooded area.

Per International Civil Aviation Organization (ICAO) annex 13, the responsibility for investigating the accident fell to Russia as the accident occurred on Russian soil. Both countries, Poland and Russia, agreed that annex 13 would be used in this case even though the flight was flown by a military aircraft and Smolensk Northern is a joint civil-military airport not certified by ICAO. Russian President Dmitry Medvedev appointed a special state commission to investigate the accident and placed Russian Prime Minister Vladimir Putin in charge. Additional parties involved in the investigation were the Interstate Aviation Committee (IAC; Межгосударственный авиационный комитет (МАК)), accredited representatives and advisors from the Republic of Poland, the USA's National Transportation Safety Board, and the USA's Federal Aviation Administration. Poland has set up its own committee to investigate the crash of the flight and (in separate cases not bounded by MAK or Polish commission conclusion) prosecutors of both countries also investigate criminal responsibility in the case.

The final accident report, created by MAK, was published on 12 January 2011, and placed the majority of the blame for the accident on the pilots. The accredited representatives and advisors from the Republic of Poland were not invited nor present during its presentation (Edmund Klich, head of the Polish commission was informed about presentation one day before, by journalists ). Some aspects of the report were criticized by members of the Polish government, specifically that the investigation found no fault with the Russian air traffic controllers. Poland published their comments to the MAK final report on the same day (document is also available on MAK's website ). Commenting on the MAK final report Polish Interior Minister Jerzy Miller said, "We are not disputing the criticism of MAK towards the Polish side. We would have made the same criticisms; it's obvious to us. (But) In our opinion, neither the Polish nor the Russian side was prepared for the safe realisation of that flight." and Edmund Klich, the head of the Polish investigative commission said: "In the description about actions of the crew, the report shows the truth. (...) Although it is possible to discuss the statement that the pilots did not respond to the command given: "level". The command "level" (...) was given too late." Poland also says that the report was not created in full compliance with Annex 13 to the Convention on International Civil Aviation because some requested documents and evidence were not provided by Russia. Additionally Polish comments to the final report were not agreed to nor fully applied. Polish comments to the report are not part of it, however they are published on the MAK website among other appendixes. The MAK defended their report and stated they would accept any international investigation or audit of their findings. Despite of no access to some evidences (wreck of plane, original recorders from plane are in Russia, 13 recorders including radar recorder and camera mounted in Air Traffic Control tower were not provided to Poland - according to MAK report all were broken and did not save any data ) The Polish Committee for Investigation of National Aviation Accidents published its report on 29 July 2011. According to the Polish report the main cause of accident was trial approach and the descent below the allowed altitude at an excessive rate of descent in bad weather conditions, in conjunction with too late execution of the go-around procedure. Circumstances that led to this are insufficient training of the Polish pilots but also errors on part of the Russian air traffic controllers who gave wrong information to crew of Tu-154M. Criminal investigations by the Russian and Polish prosecutor's offices (which examines the criminal responsibility of individuals, rather than just reasons of accident) have yet to be concluded.

Purpose and destination of the flight
The flight was conducted for the purpose of taking many high ranking Polish officials to ceremonies marking the 70th anniversary of the Katyn Massacre, a mass murder of Polish intellectuals, politicians, and military officers by the Soviets. The site of the massacre is approximately 19 km (12 mi) west of Smolensk. The area is fairly remote; Smolensk is the only city and contains the only two airports in the area: Smolensk North Airport, where the accident occurred, and Smolensk South Airport.

The airport
Smolensk North Airport is a former military airbase now in mixed military-civilian use. At the time of the crash the airport was not equipped with a Western-style instrument landing system (ILS); the airport used to have a Russian version of ILS, but this system was decommissioned upon the airport becoming a joint civil-military airfield. The Polish aircraft was modified to use Western-style ILS. A non-directional beacon system (NDB) was installed at the airport, but such a system can be used only for a non-precision approach to the runway, as its antennas are situated on the opposite ends of the runway and thus give only basic directional information about a landing plane's position relative to the axis of the runway. Since it is a navigational aid, not a landing aid, it remains the crew's responsibility to keep track of the plane's altitude. The airport was equipped with both surveillance and landing radar. The lowest available approach minimums were 100 meters (330 ft) lowest cloud base and 1,000 meters (3,300 ft) visibility.

The condition of ground visual navigation aids on 10 April 2010 were not effective. According to the Polish report the radar was unstable and swung within +- 10%. From the photographic documentation of the polish committee it appears that the origin of components of Smolensk Nord lighting system was unknown. This wasn't how Russians said the system LUCZ-2MU. In the report from the inspection flight performed on 15 April 2010 it is stated that the approach lamps, subject to their location and how high and inbound aircraft is, can be shaded by surrounding trees and shrubs when aircraft is at distance of 400, 700 and 800 m from the runway 26. The lamps of first group (900 m) had their lights filters shattered and, of three bulbs one was ok.

The aircraft


The aircraft was a Tupolev Tu-154M of the 36th Special Aviation Regiment of the Polish Air Force, tail number 101. Built in 1990 at the Kuybyshev Aviation Plant as msn 90A837, it first flew on 29 June 1990. At the time of the accident, the airframe had accumulated 5,143 hours and 3,899 cycles. The service life of the Tu-154M is 25½ years or 30,000 hours or 15,000 cycles (whichever expires first). All three Soloviev D-30KU-154 engines were within service limits of 24,000 hours or 11,100 cycles.

It was one of two Tupolev Tu-154s that served as official government jets; the other with a tail number of 102 was a year younger and at the time of the accident it was being overhauled in the Aviakor aviation plant in Samara, Russia. The "101" aircraft had undergone a major overhaul in December 2009 and Alexey Gusev, the head of the maintenance plant that carried out the work, told Polish TV that it should not have had technical problems. The crash happened 138 flight hours after the most recent overhaul.

The aircraft used the callsign PLF 101. PLF is the ICAO three-letter designator for the Polish Air Force used to identify the operator of an aircraft by air traffic control. During radio messages, PLF is either spelt out phonetically ("Papa-Lima-Foxtrot") or the related callsign "POLISH AIRFORCE" is used.

Interstate Aviation Committee
The Interstate Aviation Committee (IAC, Russian acronym MAK) oversees the use and management of civil aviation in the Commonwealth of Independent States. The committee's Air Accident Investigation Commission is responsible for investigating civil aviation accidents occurring in commonwealth member nations. The committee is headquartered in Moscow, Russia.

Flight sequence
Note: What follows is to a large extent based on the Final Report of the Interstate Aviation Committee; some aspects are disputed by Poland.

Takeoff and en route


PLF 101 took off from Warsaw at 9:27 Smolensk time after a delay of 27 minutes. The Captain had landed at Smolensk three days earlier on 7 April in the same TU-154, though he was serving as First Officer on that flight. As the aircraft was departing Warsaw, weather conditions were rapidly deteriorating at Smolensk. A temperature inversion had developed, trapping moisture low in the atmosphere and causing a dense fog to develop. At 9:15 Smolensk time, about an hour and a half before the crash, a Yakovlev Yak-40 jet (flight PLF 031) also belonging to the Polish government carrying Polish journalists from the president's press pool landed at the airbase without incident, though conditions were rapidly worsening at the time. Shortly thereafter, between 9:20 and 9:39 MSD, a Russian Ilyushin Il-76 (tail number 78817) performed two landing attempts, but could not land because of low visibility and instead diverted to the Vnukovo Airport near Moscow. Upon PLF 101's approach towards the base, atmospheric conditions continued to worsen, and the fog continued to thicken, further reducing visibility to 400 meters. The ground control personnel stated to PLF 101 that there were no conditions for landing. The Captain then requested and was given permission to conduct a "trial" approach. The controllers instructed the Captain as to the landing minimum of 100m, to which the Captain replied, "Yes Sir!"

Stress and workload factors
Meanwhile, the situation in the cockpit was one of very high stress. As the weather continued to worsen, the crew became increasingly aware of the extreme difficulty they would encounter in landing at Smolensk. The crew may have feared a negative reaction from their passengers should they have to divert to an alternate airfield. The Protocol director was present in the cockpit from time to time, and the Commander-in-Chief of the Polish Air Force was present in the cockpit for the final approach phase of the flight including the crash itself. At one point the Navigator is heard on the CVR as saying, "He'll go crazy," apparently in reference to the President of Poland should the crew choose to divert. There may also have been some friction between the Air Force Commander and the Captain, caused by an absence of the latter from condition training.

The Captain and First officer were also likely well aware of a 2008 flight when the President of Poland ordered a change in destination right before departure and again while airborne. The Captain and First Officer were First Officer and Navigator, respectively, on that flight. Lacking charts or a flight plan for the new destination, the Captain on that flight determined he could not bring the aircraft to the new destination safely. Disobeying the President and a high-ranking Polish Air Force Commander on board, the Captain flew on to the originally planned destination. The Polish prosecutor's office would later clear that Captain of any wrongdoing in relation to that flight, and he was even awarded a silver medal of merit for national defense. However, he had not been assigned to fly the President since according to the MAK's final accident report, though Polish sources note he flew the President to New York in September 2008 despite objections from the President. The Captain involved in the 2008 incident flew the Polish Prime Minister to Smolensk on 7 April without the President on board, but he was removed from the crew of the 10 April flight which carried the President. Knowledge of the 2008 incident and its repercussions may have weighed on the crew of PLF 101, potentially placing additional pressure on them to complete their flight to the original destination.

Complicating the situation was an increased workload on the Captain. Normally, one pilot flies the airplane while another crewmember handles radio communications. On PLF 101, the responsibility for communication usually rests with the Navigator. At Smolensk however the situation was different. As the airport is not usually open for international flights and is not ICAO certified, the controllers were not required to be fluent in English, the ICAO standard language for ATC communication. As such, all communication between Smolensk ATC and PLF 101 was carried out in Russian. Russian law requires international flights landing at military airports to have a Russian "Leaderman" (navigator) on board the flight, who is then responsible for all ATC communication, which is done in Russian. In the middle of March, as part of their request for permission to conduct the flight, Poland asked for "Leaderman" services and the latest airport data for Smolensk. At the end of March, after apparently receiving no reply to their first request, Poland tendered a second request for permission to fly, but did not request "Leaderman" services. As lieutenant colonel, spokesman for the Air Force Command said: "The Russian side has not confirmed readiness to protect the flight leader". According to Final report, Russia did offer "Leaderman" services, but Poland refused, stating their crew had satisfactory knowledge of Russian and could conduct the flight without the Leaderman. In reality, the Captain was the only member of the crew who could speak adequate Russian. Therefore, upon being handed-off (transferred) to Smolensk ATC, the Captain took over communication duties from the Navigator. In a normal situation, this would dictate that the First Officer be the pilot actually flying the airplane, but as the weather was bad the Captain, as the most experienced member of the crew, elected to fly the airplane as well. Therefore, the Captain was performing two tasks simultaneously which are usually split up, increasing his workload and requiring him to divide his attention.

Approach
Under these stresses, the crew continued their approach pattern and readied the aircraft for final descent. Radios were tuned to the two Non-Directional Beacons (NDBs) present at the field, and the autopilot was set up to use waypoints from the Flight Management System (FMS) units for navigation. The crew used their second radio to contact the Yak-40 which had landed earlier, inquiring as to the weather conditions. The Yak-40 crew replied, "Well, generally it's absolute shit here," and that, "(we) were lucky to land at the last moment." The Yak-40 crew estimated visibility was 200m, but told PLF 101, "you might try...(to make an approach)." The crew of PLF 101 acknowledged this information and continued their approach. As the aircraft approached the outer marker, the crew issued pitch commands (via the CLIMB-DESCEND wheel) to the autopilot. This is not recommended for the TU-154 as the autopilot cannot maintain vertical speed accurately enough for the approach phase of flight. Manual flight mode is instead recommended. Although the crew had not requested it, the radar controller began issuing reports to PLF 101 concerning their distance from the runway and whether or not they were on glidepath. The Polish report noted that on multiple occasions the radar controller stated the airplane was on glidepath when it was not.

The Terrain Awareness Warning System (abbreviated TAWS, although more correctly referred to as an Enhanced Ground Proximity Warning System or EGPWS) fired its first audible warning "terrain ahead!" at 10:40:06. This was because the Smolensk airport, as a former military airfield not open to international flights, was not in the system's database and therefore the system did not recognize that the airplane was approaching an airport. Six seconds later, someone (most likely the captain or navigator) pressed a button on the captain's FMS panel commanding standard barometric pressure be set on the captain's main electronic altimeter. This had the effect of increasing the altimeter's reading by 170 meters. As the TAWS takes readings from this particular altimeter, this had the effect of silencing the warning. The captain's secondary (mechanical) and the copilot's main electronic pressure altimeters continued to indicate correctly. As the descent continued, the crew realized they had started descent too late. To compensate for this, they increased the vertical speed to 8 meters per second, twice the prescribed rate for a normal approach. The aircraft did not have enough drag to maintain speed with this rate of descent, so even though the autothrottles commanded idle power from the engines, the speed of the aircraft increased to approximately 35 km/h higher than specified.

Approaching 300m, the Navigator began calling out the radar altimeter's indications. This is not standard practice for a non-precision approach as the radar altimeter does not take into account the terrain around the airport. Standard practice would entail calling out the readings on the pressure altimeter, which is set according to atmospheric pressure and thereby references the elevation of the actual airport. Unfortunately for PLF 101, the terrain around Smolensk airport includes a steep valley prior to the runway.

Warning signs
At 200m, the engines were still at idle power. The TU-154 manual indicates that a go-around must be initiated at 200m if the engines are running at or below 75% N2. This is because jet engine throttle response is not linear; jet engines have to "spool up" in order to produce more thrust. At power settings higher than 78% this response is almost instantaneous; at idle power it can take a full 8 seconds for a jet engine to "spool up" to full power. On PLF 101, the N2 values were not recorded by the flight data recorder (FDR). The N1 values were, and at 200m they indicated 32%-33% N1. 75% N2 equates to 51%-52% N1 for the given conditions. As such, the engines were well below the 75% minimum N2 reading, and the crew should have initiated a go-around at this point, even though they were still above Minimum Decision Altitude (MDA). However, they did not go around, and continued descent. (N1 and N2 refer to the spools, or shafts, of a jet engine on which the compressor and turbine blades are mounted; jet engine power is measured as a percentage of maximum N1 or N2 RPM. Although the shafts are not mechanically connected, the speed of one spool can be calculated based on the speed of the other spool and atmospheric conditions. ) The Final Report would later determine that a go-around was technically possible from as low as 40m, but that 200m was the first of many times that the crew were required to go around but did not.

At 180m, the "terrain ahead!" warning again sounded on the flight deck. The crew continued descent. According to MAK's report at 100m (Decision Height) there was no "landing" or "go around" call by the Captain. If this happens the First Officer is supposed to overrule the Captain, take control of the airplane, and initiate a go-around. Poland suggests that at this point the Captain says "Go around" 8 seconds later the First officer confirms by saying "go around". (only the second of these two statements is recorded in the official transcripts by MAK; the first one may have been obscured by a simultaneous report by TAWS). Despite these calls, neither pilot initiated a go around, and the descent continued. One second after 100m altitude was reached, the TAWS alert "PULL UP" activated and continued to sound for the remainder of the flight. "PULL UP" only activates when the TAWS computer believes a collision with terrain is imminent. Therefore, when "PULL UP" sounds the crew is supposed to begin an immediate, maximum performance emergency climb (full power and angle of attack to the maximum permissible without stalling) and continue climbing until the warning stops. However, the crew once again continued descent. In a typical situation with an airport in the TAWS database, the "PULL UP" warning might not have sounded at this point. There is a method of setting up the TAWS to prevent false warnings when flying into airports not in the database, known as "Terrain inhibit" mode. However, the crew did not utilize it. Even if they had, excessive rate of descent and excessive airspeed can cause the TAWS to issue a "SINK RATE" warning followed by a "PULL UP" warning. This point (10:40:40 local time, approximately 20 seconds before the collision with terrain) is also notable because this was the moment when the aircraft had crossed the minimum allowed approach slope for this airport (2°10’). Prior to this moment, the radar controller had no reason to think that the landing attempt was not proceeding normally. The behavior of the controller was later the subject of some criticism by the Polish media. The controller remained silent for about 12 seconds after the aircraft passed the 100m mark, and, even at that point, he did not order a go-around, but, rather, issued an instruction to transit from a descent to a horizontal flight. (The decision to go around was apparently reached in the cabin of the aircraft within a few seconds of that instruction.) In addition, according to some interpretations of the radio exchange between the ground and the aircraft, the crew was instructed by the ground control to descend to 120m and either to wait for clearance to land or request one explicitly, or to inform the ground control regarding their decision whether to land or to go around. (According to MAK's report, it meant that the crew was supposed to inform the ground control of their decision to land before passing the decision altitude, and that the ground control was supposed to allow the landing as long as the runway and the airspace were clear.) None of this ever happened, with the aircraft continuing the descent through the 120m mark while the ground control remained silent. It is unknown whether the crew really understood the ground control instruction (literally, "landing additionally, 120, 3 m"), which was issued in Russian and used a relatively recent expression that was only codified in 2006.

For the next several seconds, the crew continued to call out "100 meters" as read by the radar altimeter. The aircraft was flying into a valley at this time and actually descended by 60–70 meters. The crew began calling out radar altitude every 10 meters. At 60 meters radar altitude (where the crew had set their radar altitude bugs), the First Officer called out "Go around" (this is the "confirmation" go around call referred to in the Polish comment above). Due to the terrain in the area the aircraft was actually only 15 meters above the runway at the time. Simultaneously to this callout, the FDR recorded a brief pull on the control column, likely done by the First Officer, as he instinctively started the go-around sequence of actions. According to the investigation, this attempt of a go-around was completely overridden by the auto-pilot, which was still active, and, in any event, it was not completed (protocol requires that the correct sequence of operations during a go-around attempt involves increasing thrust to takeoff mode and disengaging the autopilot, neither action was done at the time.) Flight simulator testing by the investigation concluded that had the First Officer completed a go-around at this point, the crash would likely have been avoided despite the violation of minimums and the excessive rate of descent. The investigation found that this was the last moment at which a go-around would have been successful.

Point of no return
As the crew called out "50 meters," the controller instructed "level 101," telling the aircraft to terminate descent. At 20 meters, another controller instructed "Check altitude, level." Simultaneously with this final call, the control column was pulled full aft, commanding max pitch up from the aircraft, and the throttles were moved within one second from their flight idle positions to max power. The aircraft, due to the terrain, was actually 15 meters below the runway at this time. The Russian investigation surmised that at this moment the flight crew saw the trees through the fog, and instinctively reacted in an attempt to escape their grave predicament. The crew did not disengage the autopilot, but the action of commanding max pitch up on the control column overpowered it, causing the pitch channel to disengage. The control column briefly moved to neutral at this point, then moved full aft and remained there for the duration of the flight. According to the Polish report the command ordering change to horizontal flight "level" was issued at time when aircraft was at an altitude of about 14 meters above airfield plane. Two seconds before "level" command, the aircraft commander made the decision to go around. According to the Polish committee's findings the command to level should have been issued 10 seconds sooner when aircraft was well below the glide path.

Soon after, the aircraft began hitting trees. One, a large birch with a trunk 30–40 cm wide, ripped off about 6.5 meters of the left wing, including the left aileron. The resulting asymmetrical lift caused an uncommanded roll to the left. Within 5 seconds, the aircraft was inverted, hitting the ground with the left wing followed very shortly thereafter by the nose. The nose impact resulted in forces exceeding 100g, which killed everyone on board instantly. Even without the birch tree and subsequent roll, the excessive angle of attack would have led to an aerodynamic stall approximately two seconds after the impact with that tree. This would also have led to a fatal accident. According to the Polish report, safety areas are delineated round each aerodrome to present a situation where aircraft and aerodrome could not operate because of obstacles in its vicinity. Regulations alike international, Polish, Russian provide such safety areas. After thorough analysis of terrain, obstacles and the safety area it was stated that many trees were higher than allowable (mostly about 10–11 m).

After the nose hit, the aircraft was violently torn apart by impact forces. The pieces came to rest, upside-down and slightly left and short of the runway. The largest pieces left were the wing roots (the strongest part of an airplane), the wingtips, and the tail section. The tail section came to rest backwards relative to the direction of flight. A small fire started, but was quickly brought under control and extinguished by rescue crews 18 minutes after impact.

The Governor of Smolensk Oblast, Sergey Antufyev, confirmed that there were no survivors of the crash. Pictures from the scene showed parts of the aircraft charred and strewn through a wooded area. The Russian Prime Minister, Vladimir Putin, said that the bodies of those killed in the crash would be brought to Moscow for identification. Kaczyński's body was identified in Smolensk and was flown directly to Warsaw on the afternoon of 11 April.

Immediate actions
Within hours of the crash, the President of Russia, Dmitry Medvedev, announced the establishment of a special commission for the investigation of the accident. The commission was to be supervised by Prime Minister Vladimir Putin. An Investigation Committee of the Prosecutor General of Russia started a criminal case in accordance with a "violation of the safety rules" of the Russian Criminal Code.

Flight recorders
Two flight recorders, the Cockpit voice recorder (CVR) and the Flight Data Recorder (FDR), were recovered undamaged from the crash site during the afternoon/early evening of 10 April, as was confirmed by Sergey Shoygu, the Russian Minister of Emergency Situations. That evening, it was reported that the CVR recordings confirmed the crew attempted to land against the advice of air traffic controllers. A third flight recorder, a Quick Access Recorder (QAR) designed for maintenance diagnostics, was found on 12 April. The two Flight Management System (FMS) units were also recovered. Despite not being designed to withstand a crash, the investigation was able to obtain information from the electronic memories of the Quick Access Recorder and one of the FMS units. Since the FMS units are linked together, being able to read the memory of one meant the investigation was able to determine the actions performed by both units. It would later be discovered that the FDR was partially defective and had occasional gaps in its data, but as the QAR managed to survive the crash, by synchronizing the data from the two units a complete picture of flight data emerged.

On the day after the crash, investigators said they had reviewed the flight recorders, and confirmed that there were no technical problems with the Soviet-built aeroplane, ruling out initial theories that the 20-year-old aircraft was at fault. Alexei Gusev, general director of the Aviakor factory, said that the aircraft's three engines had been repaired and technicians had upgraded the plane's avionics at a recent overhaul the previous year. He said that there were no doubts about the plane's airworthiness.

Search for human remains
Ewa Kopacz, the Polish Minister of Health, claimed before the Sejm that after the crash, ground was dug to a depth of one meter, and even if a tiny piece of human flesh was found, it was genetically tested. However, in the transcript released online by the Sejm, the meaning of her speech was changed: that when a small piece of flesh was found, the ground was dug to a depth of one meter. Moreover, in September 2010, one of the Polish pilgrims to Smolensk found a jaw with teeth and two other bones.

International cooperation
Russia offered full cooperation to Polish prosecutors during the investigation. According to the Interstate Aviation Committee (IAC) Polish investigators in Russia have been given access to all procedures of Russian investigators. However, Bogdan Klich, the head of the Polish investigative commission, said that "Poland does not have a lot of things that (we) would like to have" and as an example gives lack of documentation of Smolensk airport and regulations about Air Control. Polish investigators do not have the authority to conduct investigative actions by themselves, but they participated on equal terms with their Russian counterparts in the interviews with people involved and other parts of the investigation. Polish officials were to secure all Polish state documents found in the wreckage, as well as electronic devices (portable computers and mobile telephones) belonging to government officials and military officers. In turn Russian investigators received from Poland materials secured after the crash, including those about the technical state of the aircraft and fitness of the pilot. The Polish investigation results were to be based in part on Russian findings, but they are not bound by the results of the Russian investigation. Preliminary results of the investigations were to be released on the Thursday after the crash (including the cockpit voice recordings), but this was postponed until after the weekend when the funeral of the Presidential couple was to take place, then postponed indefinitely until the full analysis was completed. The Flight Data Recorder and Cockpit Voice Recorder, both of Soviet design, were analyzed in Russia with the participation of Polish experts. The Quick Access Recorder, designed and produced in Poland, was sent to Poland and analysed there, with the participation of Russian experts. The Flight Management System units, manufactured in the United States, were analyzed there with the participation of the FAA, NTSB, Polish experts, and Russian experts.

Airport and pilot communication
The airport's traffic control communicated with the pilots in Russian, and one of the controllers claimed the Polish crew had problems communicating in this language. However, according to Tomasz Pietrzak, the former commander of the Polish 36th Special Aviation Regiment, the captain of PLF 101 was fluent in Russian and English. The Captain had landed in Smolensk three days before the crash, when he was part of the crew bringing Polish Prime Minister Donald Tusk to the 7 April ceremony, and at the time no communication problems with ground control were reported. However, while the captain knew Russian, the rest of the crew did not, in particular the navigator whose task it is to communicate with the ground, thus placing an additional workload on the captain. A Russian navigator which accompanied previous flights to Smolensk was not provided for the April 2010 flights, with differing reasons for this given by Polish and Russian sides. The final accident report would later conclude that the Captain's knowledge of Russian was "satisfactory."

The airport, which normally should have been closed due to the severe conditions, was not declared closed as its management feared that this could cause a diplomatic incident. According to the news agency Interfax, the pilot was told that Smolensk North Airport was enveloped in thick fog and strongly advised against landing, but still he decided to continue with the original flight plan to Smolensk and attempt a landing. According to an interview with a flight controller Pavel Plusnin it was suggested to the pilot that he land at an alternative airfield in Moscow or Minsk. According to Plusnin, the pilot said, that he would attempt one approach, and if landing was not possible, he would then divert to another airfield.

There was some concern in the press as to whether or not Russian military ATC had the authority to issue military orders to PLF 101 as the aircraft was a military flight. Under Russian law, military flights are under the control of Russian military ATC, and permission or denial for approach and landing must be given by the controller prior to these actions being undertaken by a flight crew. The final accident report determined that, as a foreign military aircraft, Russian controllers did not have the authority to issue military orders to PLF 101, and this had been communicated to the ATC personnel who handled the flight. The "trial" approach was conducted with the understanding by ATC that all risk for such an approach was to be undertaken by PLF 101 and not ATC.

Theft from victims
On 6 June 2010, it was reported that payments worth €1,400 had been made from a credit card found on the body of historian Andrzej Przewoźnik, one of the victims of the crash. Credit cards belonging to the politician Aleksandra Natalli-Świat were also missing, but not used in transactions. On 8 June 2010, ITAR-TASS reported that four soldiers of Unit 06755 had been charged in connection with the theft, after being found in possession of three credit cards used to withdraw a total of руб60,345. A Polish spokesperson said that the first withdrawals using the cards had been made around two hours after the crash. The Polish government admitted that the Russian soldiers involved in the theft were probably conscripts, and that earlier reports blaming members of Russia's OMON forces for the theft had been a mistake.

Initial reports
An initial report by CIS’ Interstate Aviation Committee (Межгосударственный авиационный комитет (MAK)) revealed that all three engines were operating normally, and that there was no fire or explosion before the aircraft crashed. According to the newspaper Dziennik, Polish flight recorder ATM-QAR registered that precisely at 8:41:02,5 (Polish time) the tail of the aircraft separated. All systems of Tu-154 stopped working at 8:41:04. Fuel temperature was below 0 °C (32 °F). Engines when the aircraft was above the road were at 60% of their nominal power (Tu-154 needs about 10 seconds to get 100% of power from engines). They also determined that the aircraft was 40 m lower than it should have been.

The discrepancy among the time of the crash registered by MARS flight recorders (10:41:05.4), ATM-QAR recorder (10:41:04), and when electricity lines were cut by the crashing aircraft a second or two before the final crash (10:39:35) was never explained.

On 19 May 2010, the preliminary report of the investigation into the crash was published. Alexei Morozov, the head of the technical commission of Russia’s Interstate Aviation Committee, stated that the Tupolev Tu-154M had no mechanical faults, and that an air traffic control official at Smolensk North Airport had "warned twice that visibility was 400 metres (1,312ft) and that were no conditions for landing". The investigation ruled out a terrorist attack, explosion or fire on board the aircraft as the cause of the crash. It was also reported that the voices of two non-crew members were heard in the cockpit during the period leading up to the crash. One of the voices was identified by sources as the Polish Air Force Commander, Lieutenant General Andrzej Błasik. The other voice was later identified as the Director of Protocol.

According to the Interstate Aviation Committee report from 19 May 2010, the aircraft first hit an 11 metre tree approximately 1100 metres from the runway. The aircraft was also off by 40 metres from the extended middle line of the runway. The TAWS alarm "Pull up!" was first sounded at 100 metres altitude and then repeated several times before the crash. It was first sounded 18 seconds before hitting the tree and the crew attempted to abort landing 13 seconds later. Due to geographical relief the aircraft was actually 15 metres below the runway at the time of the first impact.

On 26 May 2010, it was reported that pilot error had been identified as the reason for the crash. Edmund Klich, the head of the Polish investigative commission, stated in an interview "Pretty much everything is clear right now and nearly all evidence has been gathered". “The pilots ignored the plane's automatic warnings and attempted an incredibly risky landing,” Klich said. According to the report, the crew of the Tupolev Tu-154M failed to respond for 13 seconds when the plane's "terrain approaching" alarm warned that the aircraft was less than 100 metres from the ground. The aircraft attempted to pull up after hitting a five metre tall birch tree, but part of the left wing had been sheared off in the impact. The aircraft then went into a roll before landing on its back and disintegrating five seconds later. Edmund Klich declined to speculate on whether the pilot had been placed under pressure to land, commenting: "Psychologists will have to assess the stress levels the pilots were subjected to.

On 1 June 2010, Poland’s Interior Ministry published a transcript from the cockpit voice recorder of the crashed TU-154M. The transcript confirmed earlier reports that the aircraft had attempted to land in bad weather against the advice of air traffic control and the plane's terrain awareness warning system. At one point in the recording, Mariusz Kazana, the Director of Diplomatic Protocol in the Ministry of Foreign Affairs, enters the cockpit and was told by the pilot "Sir, the fog is increasing. At the moment, under these conditions that we have now, we will not manage to land" to which Kazana replies "Well, then we have a problem."

Expert commentators have noted that the flight navigator, who was listing the altitude readings on the transcript, was referring to the radar altimeter (which gives height above ground) rather than the pressure altimeter (which would provide the height relative to the level of the runway). Because the terrain rises up to the runway, this could have had the effect of causing the pilot to fly far too low. The Final report confirms this is exactly what happened.

Final accident report
The MAK completed their investigation on 20 October 2010. A copy of the report was sent to the Polish authorities, who had 60 days to comment, after which the report was published on 12 January 2011.

After Interstate Aviation Committee (IAC) report's publication, Poland stated that it was created in violation of Annex 13 to the Convention on International Civil Aviation because some requested documents or evidences were not be provided by Russia  and, according to a Polish lawyer, because Polish comments to the final report were not agreed to nor fully applied.

The final report noticed that the Captain's electronic altimeter was set 170 meters higher than real position. This change was made after the aircraft began its final approach and soon after the first TAWS warning sounded. All other altimeters on board were set correctly. The investigation also determined that the controller's radar screen was not calibrated correctly and showed the airplane as being 90–150 meters closer to the runway than it actually was. Additionally, his radio calls to the crew regarding their distance to the runway were given in advance by an average of 500 meters.

As part of their investigation, MAK conducted an experiment in a TU-154M simulator to determine how late the crew could have gone around. "The experiment confirmed that during approaches in conditions similar to the flight conditions of the T-154M… with a similar flight profile with vertical speed of descent of 7–8 m/sec… the aircraft characteristics guaranteed safe go around from the height of 40 m (without taking into consideration the possible obstacles and terrain along the flight path)." Taking into consideration the terrain at Smolensk, the investigation determined the last moment a go-around maneuver would have been successful was coincident with the First Officer calling "Go Around" and briefly pulling the control column at 60 m.

Polish comments on the draft of the final report
On the same day that the final report was published by MAK, Poland published its comments on the draft of the final report sent to MAK before. Poland states that their comments were not taken into consideration. MAK did not include them in the report, but published this document on its website among other appendixes. Poland also published a final version of MAK report with changes performed by MAK in reaction for Polish comments highlighted (red color means changes of text, blue means text addition).

Main points of Polish comments:
 * A list of documents, evidence, and other information requested by Poland but not received from the Russian side (First table in document "Lista Wystapien Strony Polskiej o Dokumentacje", List of requests from Poland about documentation. Entry "Nie otrzymano" means "Not received"). Sample of them: Standards of certification for usage of military airports on the Russian Federation territory, Instructions for flights in Smolensk area.
 * Poland notes that, according to international agreement between Poland and Russia from 1993, PLF 101 was classified in Poland as a military plane and should be treated as performing a military operation also on territory of Russian Federation, especially in non-classified airspace and during approaching a military airport, without ICAO certification. In military operation ATC can give order to crew about landing decision in opposite to civilian flight when ATC gives only recommendation, but final decision about landing is pilots' responsibility.
 * Information that result of analysis of CVR (Cockpit Voice Recorder), performed by Polish Commission for the Investigation of National Aviation Accidents, says that first officer gives command "go around" at 100 m altitude  This analysis has been ignored by MAK's final report.
 * Request for document confirmation that Commander of the Landing Zone was allowed to work in bad weather conditions. Documents confirm only admission for work at day and night in normal weather conditions. Poland notices also that Commander of the Landing Zone had never before worked at Smolensk and in last 12 months performed this function only 7 times. All that information is in his testimony. There is no documentation which certificate Commander of the Landing Zone on Smolensk airport which is required by Russian Law.
 * Polish position that ATC gives wrong information for PLF 101 ("on course, on glide slope") and "Level 101" was given too late. According to Final Report at this moment plane was up to 15–20 meters above runway level and 1400 meters before runway begins.
 * Differences in approach card described by Final Report and approach card received by Poland before 10 April 2010 with information that Russia sent documents without information about reference system of coordinates in document. Poland assumed that coordinates are expressed using WGS-84 which is world wide standard. Current standard for reference system used in Russia (according to its own law regulation) is PZ-90 which differ from WGS-84 by less than 40 cm (16 in) in any given direction.
 * Doubts about Smolensk compliance with Russian regulations because there were trees and other obstacles in an area 300 to 900 m long before the runway. The heights of these obstacles are 15m higher than allowed (according to both Russian and ICAO regulations). After the accident, trees in this area were cut. The structure of flight PLF 101 began to be destroyed in that area.
 * Polish explanation that there is no requirement in Military aviation for aircraft to have insurance (PLF 101 was owned and maintained by the Polish Military) and even civil regulations allows other financial protections besides insurance. In the case of PLF 101, the Polish National Treasury was financially responsible for the aircraft.
 * Polish explanation that, according to Polish law, Certificate of Airworthiness is required for civilian planes and is not obligatory for military machines — instead of this certificate, Polish military planes have to accomplish conditions regulated by "Instrukcja służby inżynieryjno-lotniczej Lotnictwa Sił Zbrojnych RP" (Instruction for engineering and aviation service of Aviation Forces in Republic of Poland). Poland also provides list of documents that confirm plane compliance with that document.
 * Information that Polish side had not received documentation of control flight over Smolensk nor documentation of RSP-6m2 radar system used in ATC.
 * Doubts about reliability of protocol after control flight which confirmed that light system (LUCZ-2MU) is working properly on Smolensk when MAK Final Report says it did not. Polish specialists were not allowed to be present during control flight.
 * Doubts about proper work of radar display according to protocol from control flight.
 * Request for source data to marker location on radar display described in Final Report. Information provided to Poland says that camera recorder in ATC was corrupted and there is no information about any other source data.
 * Request for information about 13 recorders mounted in ATC, and data recorded (even corrupted) for analysis. MAK states that camera, voice recorders and photo laboratory not worked properly and a lot of information was not saved.
 * Information that FCOM of TU-154M in fact does not prescribe using the autopilot during non-precision approach, however this is also not forbidden.
 * Expressed lack of any document that confirms PLF 101's status under Russian law.
 * Request for source data and method of calculation of PLF 101's weight. Poland says that original documentation about loading and weight measure was destroyed.
 * Allegations that documents certifying the medical examination of air controllers had manual corrections and are inconsistent with their testimonies where they confirmed that medical point was closed on 10 April 2010.
 * Correction of number of specialists — with list of their certifications — that performed technical support on PLF 101

Polish publication of ATC tapes
At a 18 January 2011 press conference, the Polish investigation made public the information contained in ATC recordings, and their analysis of such. They concluded that the "on course, on glide path" calls given to the pilots were made when the aircraft was actually off course, and furthermore the "Level!" call was given 11 seconds too late.

MAK publication of ATC tapes
In response to the Polish claims of publicity MAK published transcripts of ATC recordings on its website. The announcement made on MAK website states that the transcripts are based on a copy of recordings identical to the one which was given to the Polish side during the investigation.

The transcripts include: "Open microphone", phone calls and radio transmissions. The transcripts show that communication between the ATC and PLF101 was done mostly in Russian with only a few English phrases.

MAK report
The MAK report found the "immediate cause" of the accident was the failure of the crew to make a timely decision to proceed to an alternate airport despite being warned of the poor weather conditions at Smolensk. Another immediate cause was the descent below minimums without visual contact with the ground as well as ignoring numerous TAWS warnings. This led to controlled flight into terrain. Additionally, the MAK report found an "immediate cause" of the accident was the presence in the cockpit of the Commander-in-Chief of the Polish Air Force, which placed "psychological pressure" on the Captain to "continue descent in conditions of unjustified risk with a dominating aim of landing at any means."

A "contributing factor" to the accident was a long discussion with the Protocol director and the crew of the Yak-40 regarding the actual weather and the impossibility of landing at Smolensk in such weather conditions. The report found this discussion caused the Captain to experience "clash of motives." On one hand he knew that landing in the reported weather conditions was unsafe. On the other hand he faced strong motivation to land at Smolensk anyway. He expected a strong negative reaction from the President if he chose to divert the airplane and land at an alternate airport.

Other "contributing factors" were a lack of compliance with standard operating procedures, a lack of crew resource management, and a significant gap in bad weather flights by the PIC (he had not flown in weather conditions similar to Smolensk that day in four months). Additional "contributing factors" were the Navigator calling out radar altitudes without considering the uneven terrain in the area, utilization of the autopilot and autothrottles much lower than minimum descent altitude which did not comply with the Flight Crew Operations Manual for the TU-154, and the late start of the final descent which caused the crew to maintain a higher than normal vertical speed.

A "systemic cause" of the accident were "significant shortcomings in the organization of flight operations, flight crew preparation and arrangement of the VIP flight in the special air regiment."

Polish report
The Committee for Investigation of National Aviation Accidents published its report on 29 July 2011, also available in English and Russian. While the report stated that pilot error was the main cause of the accident, with the crew lacking adequate training in operating in adverse weather conditions, it differed from the Russian report. The main differences are:
 * conclusion that pilots did not want to land and after reaching 100m altitude (measured by radio altimeter) they decided to go around using automate mode of ABSU (it was impossible with plane and airport configuration at the moment of accident and this attempt delayed manual go-around ).
 * information that no pressure of any kind was put on pilots to force them to land according to evidence
 * information that Smolensk airport was not prepared for descending due to a lot of obstacles in the area before the runway
 * information about defective lighting installation of runway at Smolensk
 * information about misleading confirmations passed on to the crew by air traffic control which told that plane is on correct course and glide path.
 * information that approach card received by Poland from Russia was incorrect and usage of them result in entering bad data to navigation system (GPS/FMS) of TU-154m with error about 116 meters to north from real position of Aerodrome Reference Point of Smolensk airport

Cause of Accident according to Polish report:

"The immediate cause of the accident was the descent below the minimum descent altitude at an excessive rate of descent in weather conditions which prevented visual contact with the ground, as well as a delayed execution of the go-around procedure. Those circumstances led to an impact on a terrain obstacle resulting in separation of a part of the left wing with aileron and consequently to the loss of aircraft control and eventual ground impact"

Circumstances Contributing to the Accident :


 * 1) Failure to monitor altitude by means of a pressure altimeter during a non-precision approach;
 * 2) failure by the crew to respond to the PULL UP warning generated by the TAWS;
 * 3) attempt to execute the go-around maneuver under the control of ABSU (automatic go-around);
 * 4) Approach Control confirming to the crew the correct position of the airplane in relation to the RWY threshold, glide slope, and course which might have affirmed the crew's belief that the approach was proceeding correctly although the airplane was actually outside the permissible deviation margin;
 * 5) failure by LZC to inform the crew about descending below the glide slope and delayed issuance of the level-out command;
 * 6) incorrect training of the Tu-154M flight crews in the 36 Regiment.

Conducive circumstances :


 * 1) incorrect coordination of the crew's work, which placed an excessive burden on the aircraft commander in the final phase of the flight;
 * 2) insufficient flight preparation of the crew;
 * 3) the crew's insufficient knowledge of the airplane's systems and their limitations;
 * 4) inadequate cross-monitoring among the crew members and failure to respond to the mistakes committed;
 * 5) crew composition inadequate for the task;
 * 6) ineffective immediate supervision of the 36 Regiment's flight training process by the Air Force Command;
 * 7) failure by the 36 Regiment to develop procedures governing the crew's actions in the event of:
 * 8) * failure to meet the established approach criteria;
 * 9) * using radio altimeter for establishing alarm altitude values for various types of approach;
 * 10) * distribution of duties in a multi-crew flight.
 * 11) sporadic performance of flight support duties by LZC over the last 12 months, in particular under difficult WC, and lack of practical experience as LZC at the SMOLENSK NORTH airfield.

Notable passengers
In addition to Kaczyński and his wife Maria, and Ryszard Kaczorowski, the former last President of Poland in exile, on board were the military chiefs of staff (army, air force, navy), the national bank governor, a deputy foreign minister, head army chaplain, head of the National Security Bureau, three deputy parliament speakers, Olympic Committee head, the civil rights commissioner Janusz Kochanowski, and at least two presidential aides and widely known national lawmakers (including core members of the Law and Justice party), the Polish foreign ministry said.

Political aftermath
In accordance with the Polish Constitution, on the President's death his duties were taken on by the Marshal of the Sejm (speaker of the lower house of the parliament)—at the time Bronisław Komorowski, who thus became Acting President of Poland. Within two weeks he was obliged to announce the date of the popular presidential election, to be held within a further 60 days on a weekend. Kaczyński was up for re-election in late September or early October, before the end of his first five-year term.

Despite the deaths of the president and numerous officials, the crash was not expected to impair the functions of the Polish government, since no cabinet ministers were aboard the plane. The Polish Armed Forces were dealt a severe blow, however, since all of their senior commanding officers were killed; their duties were automatically taken over by respective deputy commanders, following standard contingency plans for such a situation.

The commemoration of the 70th anniversary of the Katyn massacre was split up because of the political conflict between the liberal-conservative government of prime minister Donald Tusk and national-conservative President Kaczyński. On 7 April, Tusk, along with government officials and members of his Civic Platform party, went to Katyn on invitation from the prime minister of Russia, Vladimir Putin. The official commemoration, organised by Polish Council for the Protection of Struggle and Martyrdom Sites, was scheduled on 10 April. Nevertheless, both ruling coalition and opposition were represented on the plane, with six and nine members of the Sejm, as well as one and two from the Senate, respectively, some of them well known in Poland. Many passengers were actively opposed to Tusk's policies, including:
 * President Kaczyński himself,
 * president of the National Bank of Poland, Sławomir Skrzypek,
 * chief of Institute of National Remembrance, Janusz Kurtyka,
 * Polish Ombudsman Janusz Kochanowski,
 * Jerzy Szmajdziński, the left-wing candidate in the upcoming presidential election.

The President of the Association of Former Intelligence Officers and former CIA analyst, S. Eugene Poteat, has written that political violence should not be ruled out under the circumstances of the aircraft crash.

The Marshal of the Sejm, Bronisław Komorowski, had previously been announced as the Civic Platform's candidate in the presidential election. He suggested that the date of the elections should be decided by the parliamentary opposition, with him acting merely to guarantee that the Constitution is respected.

On 17 April, one week after the crash, a memorial service, including a two-minute silence, was held to honour the victims of the crash. It was reported that over 100,000 mourners attended the event, held in Piłsudski Square; however, up to 1.5 million had been expected.

State funeral
The funeral service for the presidential couple took place in Saint Mary's Basilica in Kraków on 18 April. The couple were buried in a crypt below Wawel Cathedral]] a place traditionally reserved for people considered to be heroes of Polish history.

Presidential election
The first round of the election to elect President Kaczyński's successor was held on 20 June 2010. Since no candidate obtained an absolute majority, a run-off was held on 4 July 2010, between the two highest-polling candidates: the acting president Bronisław Komorowski, and the late president's brother Jarosław Kaczyński. While commentators noted that PiS gained some sympathy votes, it was not seen as a decisive factor in the election. In the second round of the election, Komorowski defeated Kaczyński with 53% of the vote.

VIP flight reorganisation
Following the publication of the Polish Accident report, the 36th Special Aviation Regiment which operated the flight was disbanded, and 13 Polish military officers were dismissed. Most Polish officials will now fly on regular civilian flights. Two Embraer 170s will be retained for government VIPs, but will be flown by civilian pilots and operated by LOT Polish Airlines. The remaining aircraft from the regiment, including the surviving Tu-154, are to be sold.

Poland


In Poland, the public reacted with shock and grief to the disaster. Almost immediately after the news broke, tens of thousands of Poles assembled at the Presidential Palace to lay tributes, including flowers, wreaths, and candles.

A week of national mourning was declared in Poland. Poles around the world mourned Kaczyński and set up shrines in the week that followed. Many wept openly. Flags flew at half mast in Poland. Sports fixtures, including women's U-17 UEFA Championship elite qualifying phase game Poland versus Republic of Ireland in Ukraine, were postponed. Concerts were cancelled.

On 11 April, Kaczyński's body was flown to Warsaw on a military plane; tens of thousands of Poles gathered at both the airport tarmac and the streets of the city to pay their respects to the late president as his casket was driven by hearse to the Presidential Palace. Afterwards, the casket was laid in state at the Palace. The casket remained there throughout the week, until Kaczynski and his wife were laid to rest at the Wawel Cathedral a full week after the crash, on 18 April.

On 15 April, Polish scouts put a wooden cross in front of the Presidential Palace at Krakowskie Przedmieście in Warsaw to commemorate the 96 victims of the Polish plane crash. The establishing of the cross provoked much controversy in Poland. Polish politicians began a dispute. The topic of the dispute was where the cross should be placed. Some people, mainly Catholic Church members, said the cross should stay in front of the Presidential Palace, because it is "manner worthy of remembrance". Other people said the cross should be moved to the St. Anne's Church, because the Presidential Palace, Warsaw is secular place and it should be "without signs of religion". A lot of people of the another religion than the Catholic religion were outraged and disappointed. The Catholic Church in Poland did not make any comment about the situation. During the summer of 2010, there were several protests. The acting president of Poland, Bronisław Komorowski said the cross should be transferred. After many disputes and the turbulent summer of 2010 in Poland, on September 16, 2010, the cross was transferred to the St. Anne's Church. Also, during the summer of 2010, the people in Poland commemorated the 96 victims of the plane crash by putting the arrays. One of them was placed on the wall of the Presidential Palace. Shortly after, an elderly, unknown man poured filth on the wall.

A public noon commemoration ceremony in Warsaw's Piłsudski Square was attended by more than 100,000 people on 17 April. Sirens sounded and bells tolled around the country. A three-gun salute was fired. People waved the flag of Poland complete with black ribbons and the names of the those who died in the crash were read out from a white stage decorated with a giant cross and photographs of the dead. The crowds bowed their heads.

On 18 April, the couple's caskets were driven at a slow pace through the streets of Warsaw, passing the city hall and a museum dedicated to the 1944 Warsaw Uprising which Kaczyński favoured. The funeral ceremony began at 2 pm local time (12:00 UTC) with a Mass held at Kraków's St Mary's Basilica, with thousands attending. Archbishop of Kraków Stanisław Dziwisz presided over the ceremony, and addressed President of Russia Dmitry Medvedev personally: "The sympathy and help we have received from Russian brothers has breathed new life into a hope for closer relations and reconciliation between our two Slavic nations".

Former president Aleksander Kwaśniewski told TVN24 that "It [Katyń] is a cursed place. It sends shivers down my spine. First the flower of the Second Polish Republic is murdered in the forests around Smolensk, now the elite of the Third Polish Republic die in this tragic aircraft crash when approaching Smolensk North Airport." Polish Prime Minister Donald Tusk stated that, "The contemporary world has not seen such a tragedy".

Former Polish Prime Minister Leszek Miller, who had himself suffered injuries in a helicopter crash while in office, said that Poland's aircraft were known to be in need of replacement, despite the lack of evidence that anything was wrong with the particular airplane. "I once said that we will one day meet in a funeral procession, and that is when we will take the decision to replace the aircraft fleet," he said.

Since the crash, conspiracy theories have spread in Poland about the cause of the disaster. Artur Górski, a Polish MP belonging to Kaczyński's Law and Justice party, claimed that the Russians in the Smolensk North Airport's control tower were ordered to keep the plane from landing so that the president could not attend the Katyń ceremony, resulting in the crash. Górski apologized for his remarks, saying that he had been in a "state of shock". In November 2010, Law and Justice members Anna Fotyga and Antoni Macierewicz travelled to Washington, D.C. with an open letter by Jarosław Kaczyński and a petition of 300,000 signatures from the Association of the Katyn Families 2010 (Stowarzyszenie Rodzin Katyń 2010), calling for the U.S. government to launch an independent international investigation into the crash. Fotyga, Macierewicz, and Jarosław Kaczyński have become critical of the Russian-led investigation, and have indicated suspicion that the Russians have engaged in a cover-up over the disaster; Polish government spokesman Pavel Gras called their action an "absolute scandal" and "on the verge of treason." In April 2012 Jarosław Kaczyński stated in national Polish television that there is only one theory that explains the crash and events that happened afterrwards, and it is the theory of assasination and explosion in the plane and called on international experts to investigate the catastrophy.

Russia


Russian President Dmitry Medvedev and Prime Minister Vladimir Putin expressed their condolences to the acting President and speaker of the parliament, Bronislaw Komorowski. President Medvedev also announced that 12 April 2010 would be a national day of mourning in Russia. Chairman of International Committee of the State Duma Konstantin Kosachev said that "Katyn claimed yet more victims". Chairman of the State Duma Boris Gryzlov has expressed condolences.

Russians and foreigners laid flowers and candles at the Polish embassy in Moscow, and at the Polish consulates-general in Saint Petersburg and Kaliningrad.

After the aircraft crash, state owned Russia Channel broadcast the film Katyń for the second time in Russia. The film, which was not distributed in Russia, was first shown in Russia on another state-owned channel, the less popular Kultura Channel on 2 April 2010. The first showing of Katyń was a political event, which was followed by a serious discussion of Polish-Russian relations by politicians and public figures, and drew high audience numbers for the smaller channel, with an estimated 100 million Russian viewers.

While Polish commentators saw Putin's participation in the 7 April ceremony as a symbolic gesture, they were touched when Putin and Tusk paid tribute and laid flowers at the site of the crash. Tusk knelt and briefly hid his face in his hands, then stood up as Putin patted him on the shoulder. The two hugged, then gave a joint press conference on the investigation into the crash. Polish commentators noted this was a human gesture, and a display of emotion that Poles had longed to see from their eastern neighbours.

On 11 April, holding a bouquet of red roses, Putin was reported to have appeared truly distressed as he escorted Kaczyński's body to a Warsaw-bound plane. Later Putin said in a Polish television interview: "This is of course first and foremost Poland's tragedy and that of the Polish people, but it is also our tragedy. We mourn with you".

The Russian response has been noted favourably by Poles, with talk of a thawing in the relationship between Russia and Poland. Witold Waszczykowski, deputy head of Poland's National Security Bureau, told Reuters, "We did not expect this gentle, kind approach, this personal involvement from Putin. Naturally it will have a positive impact on the relationship between our countries." Jerzy Bahr, the Polish ambassador to Russia also stated, "We can sense Russian solidarity at every step of the way."

As part of this thawing of relations, on 28 April, 18 days after the crash, Russia's state Archive publicly published on their website a number of previously secret files on the Katyn Massacre. The files were declassified in the early 1990s, but before the 28 April publication they were only available to specialized researchers.

The strongest admission was yet to come. On 26 November 2010, the Russian State Duma passed a resolution admitting that Soviet leader Joseph Stalin personally approved the Katyn Massacre. The Soviets had long claimed Nazi Germany were the ones responsible. Though this stance changed in 1990 when Mikhail Gorbachev admitted the Soviet NKVD secret police carried out the massacre, the November 2010 resolution was the first time the Russian government admitted direct involvement by Stalin.

In an interview with Rzeczpospolita, Andrei Illarionov, Vladimir Putin's former advisor, noted, “...contrary to the promises, the investigation of this crash is neither transparent nor dynamic." and added, “...the Polish side does not have full and free access to documents and evidence.” Illarionov was also one of the signatories of an open letter written by Russian dissidents, which voiced concerns about the conduct of the investigation. According to the letter, “rapprochement with the current Russian authorities is more important for the Polish government than determining the truth about the plane crash.” Polish Prime Minister Donald Tusk responded that his government would obtain flight data from the Russian investigators before making its own judgment and revealing it to the public.

International
Many countries, international organisations and other entities expressed sorrow and condolences to the people of Poland over the crash. A national day of mourning was proclaimed in the European Union and several countries. Victims of the airplane crash were also commemorated by a minute of silence before several football matches throughout Europe.

Some concern arose that Kaczyński's funeral would have to be delayed as a consequence of volcanic ash emanating from Iceland and the resulting air travel disruption in Europe. Only one airport in the country was open, and several international dignitaries were unable to attend. The funeral nonetheless went ahead as scheduled.

NATO was reportedly concerned over the possible compromise of many of its secret codes and communications procedures to the Russian government. Many of the Polish government and military officials on the aircraft apparently carried secret NATO communication key codes and devices which were recovered by the Russians after the crash.