Flight MH370: forensic engineering expert on the significance of debris

Plane debris found on the French island of Réunion in the western Indian Ocean has renewed hopes experts can determine the fate of flight MH370 which disappeared en route from Kuala Lumpur, Malaysia, 500 days ago. 

The recovered object, confirmed to be a moveable piece of a Boeing 777 wing (a flaperon), has arrived at a lab in Toulouse, France, where experts will examine it on August 5. 

U of T News asked Doug Perovic, a professor in the department of materials science and engineering and a renowned expert in forensic engineering, for his take on why the plane veered off course, what the recovered debris can reveal to investigators and what happens next.

What information will the experts be looking for to conclusively identify the recovered artefact as part of the missing flight MH37?
The first order of business is to examine the evidence for the manufacturer’s serial numbers. Initial photographs and video footage show that the primary identification plate has been lost, presumably due to degradation of the adhesive during exposure to seawater for an extended period of time. Fortunately, since all aircraft components are fully regulated and certified, there are several serial numbers stenciled to the various components of the artifact that will allow for identification. In addition, chemical analysis of the paint will be performed to match with Malaysia Airlines paint specifications. Photographs available to-date reveal the serial number ‘657BB’, which corresponds to a component part of a right-wing flaperon designed for a Boeing 777 aircraft. Experts will disassemble the flaperon to reveal all available serial numbers and then confirm if the artifact was part of the MH370 Boeing 777-2H6ER aircraft.

If it is established that the flaperon belonged to MH370, would that confirm that the flight ended its journey in the Indian Ocean?
Yes, and also eliminate theories of the plane crashing or landing in another part of the world. According to reports from Boeing, there are no other Boeing 777 aircraft that are unaccounted for in the Indian Ocean. If the flaperon was indeed part of MH370, the recovery of the artifact on the shores of Réunion Island off the coast of Madagascar is consistent with the flaperon entering the Indian Ocean either prior to or during the crash of the aircraft in the present search area location determined from satellite data analysis. It is interesting to note that a University of Western Australia computer modeling study of Indian Ocean currents/wind patterns (gyres) and weather systems since the date of MH 370’s disappearance 17 months ago, predicted that aircraft debris would reach Réunion Island in as little as 18 months.

What can the condition of the flaperon reveal to the investigators?
Physical examination of the complete intact structure coupled with electron microscopy analysis of fracture surfaces of the relevant subcomponents following disassembly will help determine if the mode of separation of the flaperon from the wing occurred: (i) in-air under normal flight conditions, or due to excessive speed or explosion (ii) by impact with water at steep angle with the flaperon fully stowed indicative of an aircraft deep dive scenario or (iii) by impact with water while the flaperon was fully extended indicative of a slow speed on-water ditching scenario. Examination of available photographs and video of the recovered flaperon reveal minimal compression damage of the leading edge and extensive damage of the rear trailing edge consistent with a separation of the flaperon from the wing in-air prior to impact with water. The serrated damage at the trailing edge of the flaperon is most likely a result of transonic flutter caused by excessive speeds of the aircraft as would be experienced in a dive scenario performed intentionally or following fuel run-out.

It should be noted that a US-FAA Airworthiness Directive was issued in 2005 concerning a safety deficiency associated with premature wear, fretting and fracture of Boeing Model 777 flaperon fasteners that “could lead to the flaperon becoming unrestrained and consequently departing from the airplane”. Detailed analysis of the fracture surfaces of the fastener locations from the recovered flaperon will reveal whether any defect(s) were a contributing factor to the detachment of the flaperon from the wing.

There has been much speculation about why the plane veered off course, including a preliminary assessment by U.S. intelligence agencies suggesting someone in the cockpit deliberately controlled the aircraft’s movements before it disappeared. What’s your take?
There is no disputing that MH370 made a deliberate U-turn from its scheduled flight path heading back over Malaysia shortly after the last contact made with air traffic control. The majority of media reports appear to associate ‘deliberate’ with an intentional act of murder/suicide by someone who could disable all of the communications systems and intentionally fly the aircraft into the ocean.

However, another plausible explanation is that the aircraft suffered a major mechanical/system failure rendering the communication systems inoperative. The plane could have been deliberately turned to seek assistance. It is important to note that the flight trajectory of MH370 following the first turn was directly on course back to the Malaysia Airlines maintenance facility.

It is also possible that the continued flight path of MH370 around land and over water was initially an attempt to keep a malfunctioning aircraft away from land to make a crash landing on water if/when necessary. Forensic investigation of further recovered physical evidence could distinguish between the two possible scenarios.

If it’s confirmed that the debris is from the missing plane, what happens next?
The extensive and co-ordinated search for more aircraft debris in the area around Réunion Island, Madagascar and the southern-east coast of Africa will continue in order to obtain further physical evidence for the accident reconstruction investigation. It will be important to carefully document location and time of debris discovery. Further computer modeling of gyres and weather systems can be performed to work backwards from a given debris location to help further refine the location of origin of the crash site.

Furthermore, forensic biological analysis of the growth history of barnacle shells and other arthropods attached to the recovered flaperon can be used to provide a roadmap and timeline of where and how long the flaperon travelled in the Indian Ocean. Ultimately, circumstantial evidence will likely not be sufficient to solve this great mystery. The answers lie at the bottom of the Indian Ocean, particularly with the flight data and cockpit voice recorder black boxes.