Even if the flight-control surface discovered on the island of Reunion is confirmed as part of missing Malaysia Airlines flight MH370, it is highly unlikely to aid the search for the Boeing 777-200ER.

The chaotic complexity of turbulent ocean currents and wind patterns create too much uncertainty – particularly over an extended period of time – to enable accurate reverse-modelling of debris drift.

While several entities have contributed to drift modelling for the MH370 investigation, the Commonwealth Scientific and Industrial Research Organisation says that refining the search zone for the aircraft based on the Reunion debris find would be “impossible”.

The Australian Transport Safety Bureau has illustrated the difficulties associated with such modelling, pointing out that an initial analysis of debris drift had predicted that debris could wash up on the western coast of the Indonesian island of Sumatra as early as July last year, four months after the aircraft’s disappearance.

But this possibility was effectively discounted during further modelling, after the search area for MH370 had been revised the following October. The Australian Transport Safety Bureau says that the difference in predictions from the models – which had been conducted by different organisations – was attributed to a flaw in the earlier model traced to erroneous application of wind data.

“While this error in that model had no impact on the way the surface search was conducted, it was important in order to understand over the course of time where debris might wash up,” says the ATSB.

It says this helped the investigation in its analysis of possible debris sightings off the western Australian coast.

The drift analysis for MH370 has been complicated further by the delay in establishing the probable impact location for the 777.

French investigation authority BEA noted that the Atlantic hunt for floating debris from Air France flight AF447 had been frustrated by the absence of sea-surface current data at an early stage.

Lack of reliable information, it stated, had “affected the accuracy of the reverse-drift calculation” and added to the inherent uncertainties of the simulations.

“This work demonstrated that it is important to quickly have access to data on sea-surface currents measured in-situ,” it added, and formally recommended that search aircraft be fitted with buoys which could be immediately deployed to measure drift.

The most recent drift models for MH370 have refined the CSIRO calculations and accounted for the possible effects of sea waves as well as wind and ocean current.

Simulations covering the entire period – almost 17 months – since the 8 March 2014 disappearance have shown that the overall debris drift would have probably been in directions north and then west of the likely crash site.

Expansion of the modelling to the western side of the Indian Ocean supports the possibility of wreckage being carried to Reunion and Madagascar as well as south-eastern Africa.

CSIRO says that the discovery of the component on Reunion, considered in the context of a reasonable leeward drift, “does not cast doubt” on the search zone defined for MH370, even if it cannot be further refined.

Analysis of the debris – a flaperon, which serves both as a flap and high-speed aileron – might provide investigators with insight into the impact. Such techniques were applied to floating debris from AF447 and used to establish, with considerable accuracy, the orientation of the aircraft as it struck the ocean surface. Investigators are also likely to examine biological evidence derived from any marine life on the structure.

Malaysian investigators are leading the MH370 inquiry because, under ICAO protocol, the state of registry takes precedence when the state of occurrence remains unclear. ICAO says that confirmation of the source of the debris on Reunion – a French territory – would not change this investigative hierarchy because the location of the accident site “has not yet been established”.

Source: Cirium Dashboard