Published: 2021-05-27 12:14:17 BdST
International condemnation of the scrambling of a fighter jet and the use of what turned out to be a false bomb alert to divert the flight to Minsk and detain a dissident Belarusian journalist has focused mainly on accusations of state-sponsored hijacking and rights violations.
But Europe's aviation regulator said on Wednesday that Belarus's actions had also cast doubt on its ability to provide safe air navigation, and some international officials are pushing for an investigation close to the type seen when a plane crashes or something goes technically wrong.
Opening such an investigation would test a system of global co-operation that has generally worked smoothly for decades, aviation experts said.
That's because under a global protocol called Annex 13 Belarus, as the "state of occurrence", would have the right to lead any ordinary safety probe with "unrestricted authority" over key evidence such as the plane's black boxes.
"The state of occurrence has the lead," said Michael Daniel, a former US Federal Aviation Administration (FAA) accident investigator. "However they are also the prime suspect in this case."
A probe would not take place entirely behind closed doors. The United States, where the Boeing 737 was made, and Poland, where it is registered, would be accredited. And states with passengers on board would have access to some information.
Lithuania, the destination of the flight from Greece, has said passengers included 94 Lithuanians, nine French citizens and 11 Greeks. Also on board was Russian citizen Sophia Sapega, the 23-year-old girlfriend of dissident Roman Protasevich, who was detained along with him.
Her presence on the flight could open the door to observer status for Belarus' closest ally in any investigation following normal safety probe rules.
Experts said Sunday's forcing down of the plane in Belarus was among a handful of extremely rare incidents that have exposed a loophole allowing countries accused of violations in their own airspace to control a probe carried out in the sometimes grey zone between security and safety.
Last year Iran led an investigation into the shooting down of a Ukrainian plane on its territory, blaming it on the error of a military operator. But Ukraine and Canada criticised the final report and relatives questioned the probe's impartiality.
The cockpit voice recorder has the potential to play an important role in any investigation if its two-hour loop retains a recording of communications before landing.
Belarus released what it said was an extract of the air traffic control transcript on Tuesday, but it differed from extracts previously publicised on Belarusian state TV and also appeared to contradict statements from Minsk airport officials
Belarus, which has blamed the diversion on an alleged bomb threat and accused the West of using the episode to wage "hybrid war", has invited US, European and international aviation officials to join it against "acts of unlawful interference".
But Europe's warning could favour a probe on safety grounds. These fall into categories including "accident" or "serious incident".
"It's definitely a serious incident, when you have air traffic control essentially lying to you to tell you that there is something that's putting your aircraft at risk but it's not clear why and you have to follow these aircraft and land here," said Mark Zee, founder of flight advisory firm OPSGROUP.
Daniel, the former FAA investigator, said a more international approach than usual was needed to bring "credibility and objectiveness", as happened after the downing by missile of a Malaysia Airlines jet over Ukraine in 2014.
In that case, the majority of victims were from the Netherlands, which led the probe with Ukraine's permission.
"If the investigation is not going to be able to be freely investigated by the Belarusian authorities - and that seems unlikely given the nature of the event - then you would want some other country," Zee said.
"It may be an alliance of states that will say 'we'll investigate this to the best of our ability'."
Airlines have called for a broad international probe.
The UN's International Civil Aviation Organisation (ICAO) is convening an urgent meeting of its 36-member council, which has some scope for fact-finding investigations, on Thursday.
"All the aviation authorities will take it seriously because it is unprecedented and it goes to the integrity of the air traffic management system," aviation lawyer John Dawson said.
"The whole thing about the air traffic management system is that everything is designed for a safe and efficient way to land an aircraft. When it becomes political, to get hold of a political opponent, it is obviously counter to that aim."