What could the MH370 piece reveal?

"Today, 515 days since the plane disappeared, it is with a heavy heart that I must tell you that an international team of experts have conclusively confirmed that the aircraft debris found on Reunion Island is indeed from MH370," Prime Minister Najib Razak said in televised address on August 5.

The two-meter (six-foot) long piece of wreckage, from a wing part known as a flaperon, had been found on a beach on the French Indian Ocean island on Wednesday, July 29, and taken to mainland France for closer examination. Aircraft seat cushions and window panes have also been found on the island, according to Malaysian authorities.

Flight MH370 vanished on March 8, 2014, shortly after it left Kuala Lumpur for Beijing in the early morning hours with 239 people, mostly Chinese, on board. Investigators believe an area off Western Australia - along a narrow arc in the southern Indian Ocean - is the most likely resting place of the jet.

But despite the most expensive search operation in history, an international team has yet to find evidence of any wreckage in that area. It is believed ocean currents took the flaperon to La Reunion.

Malaysia is responsible for the investigation and is managing the examination. They are being assisted by aircraft manufacturer Boeing as well as US, Australian and French authorities, who have so far stopped short of confirming whether the plane part belongs to the missing plane.

In a DW interview, aviation safety expert John Goglia, a former board member of the US National Transportation Safety Board, says that there are a number of steps and tests investigators must carry out before they can confirm the link, and explains how much could be learned about the plane's fate by closely examining the flaperon's metal and the marine life found on it.

DW: Malaysian PM Najib has confirmed that the aircraft debris found on Reunion Island is from MH370. How were the authorities able to determine the flaperon found in Reunion Island belonged to MH370?

There was initially much discussion about the printed number that was on the flaperon, but that doesn't provide any definitive answer. The investigators must have also compared the piece with the manufacturing drawings of the airplane to determine precisely whether this piece came from a Boeing 777 or not. I am sure that Boeing sent the details of the drawings of that particular airplane part to the French experts days ago.

Once they established the piece came from a Boeing 777, it also became highly likely that it was from MH370 as there have been very few accidents involving Boeing 777's in the area. And all those accidents were identified, and none of them were either in the Indian Ocean or anywhere near it.

What could this wreckage then tell us about what happened to the plane and where the other parts may be found?

It's not going to tell us anything about where exactly other parts of the missing plane can be found. But the marine growth found on the wreckage might provide a clue in this regard. The damage to the piece and to the attachment points could also tell us something about the attitude of the plane when it struck the water.

In a further step, the investigators will put the attachment points of the flaperon under a scanning electron microscope and take a look at how the metal broke.

There are a lot details to be extracted from it, but it is unlikely that they will reveal the cause of the accident or the exact location of the plane.

Aircraft seat cushions and window panes have just recently been found on La Reunion, Malaysia's transport minister said Thursday. How important are these parts and what will be necessary to determine the actual cause of the crash?

There is a remote possibility of identifying whether these parts also belong to MH370. As for the seats, for instance, the type of fabric or foam used inside the cushions might help in establishing a link to the missing plane. There is, however, nothing unique about the windows. What these new parts can tell us is that the plane did break up when it hit the water.

Investigators will then look for any indication on the material as to whether there was a fire onboard, for instance. In order to determine the cause of the crash, investigators need to gain access to the flight recorders.

Although the Malaysian PM confirmed the aircraft debris came from MH370, French authorities have so far stopped short of doing that. What do you think is the reason behind this?

I believe the investigating authorities are not going to speak publicly about it and make such a statement until they are 100 percent certain that this piece came from MH370. They don't assume anything and will take it cautiously.

One thing investigators don't like to do is to give false information, especially to the families of the victims. They know how painful every word they say and action they take is for those people left behind.

In this context, I believe that the actions of the Malaysian government - not only now but throughout this investigation - defy description; they are simply difficult to understand.

When do you expect the outcome of the entire investigation to be made public?

That's up to the French and Malaysian authorities. I think they may give us some little information but they may hold it all very close for a while.

Also, under International Civil Aviation Organization (ICAO) rules, the Malaysian government is in charge of this investigation. It doesn't matter that the French have a piece of the wreckage or that the US is also involved. The investigation is ultimately controlled by the Malaysians. So they are the ones who are going to make most of these determinations.

How important will this investigation be not only for the victims but also for the aviation industry as a whole?

The aviation industry always looks at events likes these and tries to make improvements. As for the families, I don't think it's going to help them with closure to a great degree given that they want to find the airplane.

But it does help in one sense. The confirmation that the piece belongs to MH370 will finally put an end to rumors such as the plane being on some remote island with the passengers held hostage. In that sense, it may provide some relief, but it's not very helpful in terms of closure. The families will have to continue to endure the pain from this event.

Aviation safety expert John Goglia is a former board member of the US National Transportation Safety Board.