Voice Spectrum of Malaysian Airlines Flight MH370

Sometime ago I came across the recording from the cockpit of the missing Malaysian Airlines flight MH370. The commentary from NBC News has been thoroughly examined and discussed by my forensics colleagues leaving me no reason to doubt their findings. I decided, therefore, to focus on another aspect of this recording.

Without knowing the chain of custody of a recording it is rather difficult to verify its authenticity, however it’s not impossible. In most situations like this the customer will ask the forensic audio examiner very specific questions especially in regards to the verification of its authenticity. Oblivious to the questions my colleagues were asked to answer enabled me to perform a closer examination of the recording without being influenced by their opinions. Subsequently, allowing me to ask myself this question. “Are the voices of the pilots in actual fact the voices of Captain Zaharie Ahmad Shah and his co-pilot Fariq Abdul Hamid?”

There is no doubt the recording has been edited. In saying this, there could be a very good reason associated with this editing process, particularly, when someone has to obtain the recordings from different sources as in this case. Considering the circumstances, the Malaysian authorities should have disclosed information in respect to this when the recording was submitted. This would have prevented others (including myself) from concluding that there is no evidence to say that these voices are in fact the voices of Captain Zaharie Ahmad Shah and his co-pilot Fariq Abdul Hamid.

An individual who listens carefully to the recording will clearly identify the four words “Malaysian, Three, Seven, Zero” repeated at least 16 times by the officer handling the communications. Possibly to the average listener these words may sound quite normal, and it is of course normal to hear these words repeated in a communication between the aircraft and air traffic control. For a forensic audio examiner or a forensic linguistic professional these four words contain a wealth of information with regards to the identity of the person pronouncing them. Of course in order to complete a meaningful comparison and conclusion it is imperative to have access to the voices of Captain Zaharie Ahmad Shah and co-pilot Fariq Abdul Hamid.

I have been unable to find other recordings that contain the voices of the Captain Zaharie Ahmad Shah and Fariq Abdul Hamid making it rather difficult to complete a voice comparison. Nevertheless, I have been successful in obtaining the transcript of this recording and have thereby extracted 16 instances mentioned in the transcript, which I will refer to as ‘segments’ in respect to those four words. The time location of these segments are marked in the audio of this video recording for reference purposes only. At this stage, I have not performed any initial processing of these segments such as removing background or ambient noise, they have been deliberately untouched until further notification.

Here you have the opportunity to judge for yourself if these are indeed the same voices throughout the recording. Imagine that you are a member of the jury in court where the judge instructs you to listen carefully to the presenting evidence of these segments of the recording. You can play them in any sequence, form your own opinion and draw your own conclusion. I will not try to influence you with my findings, and I will not specify what to listen for, as we exercise different patterns and methods to identify certain areas of interest, but rather ask you to trust your own ears and judgement on this. In this link below there’s a .zip file containing two folders. The first folder is labelled “Sound Files” and contains 16 .wav files (1-16 in the order they appear in this recording). The second folder labelled “Spectrographic Analysis” contains 16 spectrographic plots with the corresponding spectral properties of the sound files. In situations like this the words are normally separated and each word is displayed by a discrete plot in the spectrogram. The screenshots display the complete sentence “Malaysian Three Seven Zero”. The blue lines denote pitch information, and the red dotted lines denote formant information.