Figure 27 shows the in-service locations of these two pieces of wreckage from MH370. Each had separated from one of two identical wing panels, one on the top of the left wing, and one on the top of the right wing. Note that the identical panels are immediately in front of the flaperon on each wing. Also note that each piece separated from the exact same location on its panel – the aft outboard corner.
From an investigation perspective, it is remarkable that these two pieces of wreckage are basically mirror images of each other (I will refer to them as twins). One is from the right wing, and the other is from the left wing.
We know that only twenty confirmed pieces of wreckage have been recovered from MH370. For a curious investigator, a basic question would be: why would two of only twenty pieces be twins from opposite sides of the airplane? Could that be coincidence, or is there a logical explanation for it? We will see below that there is a logical explanation, and it is based on solid investigation analysis.
When the investigators from the official investigation looked at these two pieces, they probably thought they were typical of small pieces that would be created during a high-speed diving crash. Apparently, the significance of these twin pieces was not recognized.
Here is some basic analysis. If there had been a high-speed diving crash, and these twin pieces had actually been liberated in that type of crash, the force of the crash would have liberated at least hundreds of other pieces with similar construction. Each one of the many hundreds would have had an equal chance of floating to a shoreline. It is very far-fetched to believe that from all these hundreds of similar pieces, only these two twin pieces floated all the way to a shoreline. What are the odds of that happening? I would say close to zero. That is not a realistic scenario – it makes no sense.
Here is the reality. There never were large numbers of similar pieces created, because there was no high-speed diving crash. What happened was that these twin pieces were created by a similar and specific failure mechanism, and it happened during a pilot controlled ditching. They were liberated from the airplane because of where they were located – directly in front of each flaperon. The analysis to support this conclusion comes next.
Much of the evidence presented to this point has been supported by witness marks that you can easily see. These twin pieces have no specific witness markings that show exactly how they were liberated. However, this gives us an opportunity to see how sound investigation analysis can lead us to a logical and very supportable conclusion.
Here is that analysis. We can see in Figure 27 that the failure mechanism for each of the twin pieces was that they were simply ripped free from the wing panel they had been a part of. In wreckage analysis terms, we call it ripping and tearing damage. Such ripping and tearing damage can happen in a high-speed diving crash, but we know that MH370 was not subjected to that type of event.
That tells us that the ripping and tearing damage that liberated our twin pieces must have resulted from abnormal forces in the wing structure surrounding each piece. Logic tells us that each twin piece was liberated in the same way. Each twin piece was exposed to an equivalent abnormal force, and that force was created at about the same time, and in the same way, in each wing.
The next investigative step is to look at what is inside the wing structure beneath each of these twin pieces. Mounted inside the wing at these locations is the support structure that holds the flaperon to the back of the wing. There are also support structures for the hydraulic mechanisms that move the flaperons up and down.
In a controlled ditching scenario, these are the support structures that would be holding against the tremendous force of the water trying to drive each flaperon towards its up (retracted) position. As each flaperon got deeper into the water during the controlled ditching, those water forces would become exceptionally strong. Extraordinary stresses would build up in those localized areas of the wing structure in front of each flaperon.
It is logical to conclude that each of the twin pieces broke free from the top of its wing because of the stress concentrations and wing-skin distortions in those very localized locations. It is also logical to conclude that the localized stress concentrations and wing skin distortions were created when the extended (down) flaperons were being dragged through the water. This is all very logical analysis.
There is no logic that could explain these twin pieces in a high-speed dive scenario. The localized forces that liberated these twin pieces could not be created if the flaperons were streamlined to the water flow in an up (retracted) position, regardless of the speed the airplane entered the water. To create these localized forces on the support mechanisms, and resultant stress risers and wing-skin distortions, both flaperons had to have been extended (down), as they would be with the flaps extended (down).
We saw earlier that the right flaperon broke free from the right wing because of the spanwise crushing forces created along the right wing’s trailing edge (combined with the water forces). That happened when the airplane’s right wingtip dug into the water.
In the controlled ditching event, there would have been no equivalent spanwise crushing force on the left wing, because the left wingtip did not dig into the water. It is reasonable to assume that the left flaperon sustained equivalent erosion damage to its trailing edge, but it probably did not break completely free from the wing because it was not subjected to the same spanwise crushing forces.
The takeaway from this analysis is that it provides further proof that MH370 entered the water with its wings level (the airplane was not banked). This analysis shows that a wings-level water entry is the only scenario that explains how these twin pieces were created. And of course this analysis also adds to the proof that MH370 entered the water with its flaps fully extended (down).
With the above information, we can now review and add to the narrative about how MH370 entered the water. We know that as it approached the water surface, the airplane was in a controlled ditching attitude, with the wings level (not banked). We know that the engines would touch the surface first, and they would be ripped off.
Next, the extended (down) flaps/flaperons would start to contact the swells and waves (see Figure 8). The airplane would still be travelling at a near flying/landing speed. This is when the trailing edge damage we see on the recovered flaperon and flap section occurred. Although we do not have proof, it is reasonable to assume that similar damages occurred on the trailing edges of all the flap system pieces, as they all would have been extended (down).
As the airplane settled further into the water, the water pressure against each extended flaperon caused the localized forces that popped the twin pieces from the tops of each wing. As the airplane slowed, the right wingtip dipped and was struck by a wave/swell, and it dug into the water. This is what created the spanwise loading that compressed the trailing edge of the right wing. It was this spanwise loading, combined with water forces, that caused the recovered right flap section, and the right flaperon, to break free from the airplane. No such spanwise loading would have occurred on the left wing, which explains why similar pieces were not recovered from the left wing.
There is more that can be learned from the recovered wreckage pieces. In this section, we will assess the three individual pieces of wreckage that have been identified as being from inside the passenger cabin of MH370. The fact that they were recovered proves that during the controlled ditching, the fuselage must have been breached. That would be the only way for those pieces to escape from inside the airplane. They had to have passed through an opening (breach) in the fuselage structure.
Figure 28 shows each of the three interior wreckage pieces.