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MH370: The pings were not from the black box – William Meacham

A few months ago, a colleague at the University of Hong Kong mentioned that a great white shark had been tracked all the way from South Africa to Australia.

This came to mind on April 5 when the first ping was detected in the search for Malaysia Airlines flight MH370 and thought to have come from the airplane’s black boxes.

Stunningly, this detection occurred on the very first run of the underwater towed pinger locator (TPL), perhaps too good to be true. But the experts on TV seemed very confident, stating repeatedly that there was nothing in nature or commercial shipping that would make a similar sound.

Some preliminary research online revealed that an enormous amount of biotelemetry tracking is going on in the oceans, with pinger transmitters attached to all sorts of marine life from whales to sharks, sea turtles, tuna, seals, swordfish, etc. 

To cite just one example, the real-time tracking of more than 400 marine animals is listed at 

For several decades, pingers with frequencies of 30 to 50kHz have been commonly used to track large, deep ocean animals. Location and other data is transmitted to receivers in the ocean or to satellites whenever the animal surfaces. Acoustic pingers are also widely used as fishing net protectors, to drive away predators that would steal fish.

There are several features of the evidence obtained by the TPL that indicates the signals it received came from a tracking device, or pinger attached to a net that is drifting.

First and foremost is the signal’s frequency of 33.3khz. This is NOT within the manufacturer's specs of 37.5 +/- 1 for the black box pinger.

It was reported that three other detections by the TPL were also at that level. According to a message to me from P.H Nargeolet, an oceanographer involved in the search for Air France 447 that crashed into the Atlantic, this frequency alone proves that the signal is not coming from the missing Malaysian plane. [1]

The range of detection is another major issue. Scientists from the Woods Hole Oceanographic Institution used a pinger with the same specifications as MH370’s in their study of baleen whales. [2]

They tested the range of detection and found the maximum to be 2.3km. But the distances between the four detections of the “black box pings” were well beyond, at 9.5, 12.3 and 13.6km.

These signals clearly cannot be from the pingers on MH370’s voice and data recorders, even supposing they were separated by currents after the crash.

Dr Lee Freitag, one of the scientists in the study that I contacted, expressed scepticism that the pings were coming from the black box, and also confirmed that the frequency of the pinger would not change due to deep sea conditions. [3]

Another problem is the first detection that lasted over two hours. The ship towing the TPL was moving at 2 knots, so it covered 9km while the detection lasted.

Since it can only pick up a signal at most 3km away, this long detection suggests a target moving parallel or at an angle to the TPL.

The depth of the sea floor was around 4.5km and the TPL would be at least 1.5km away from the black box even when directly over it. Equally problematic is the second brief detection. The signal was picked up with the TPL partially deployed at a depth of only 300m, thus at least 4.2km from a source lying on the seabed.

Dr David Gallo, a senior scientist at Woods Hole and co-director of the successful search for the wreckage of AF447, wrote in an email to me: “I don't know any underwater acoustic people that think the pings have anything to do with the plane.” [4]

Two other pings were detected during the search. A Chinese ship detected a pulsing signal, reported at 37kHz. And a “fifth ping” was detected by a sonar buoy. These were dismissed as unrelated to the plane, almost certainly attributable to drifting or tracking pingers present in the search area.

The last two weeks have been focused on the area where the four “black box pings” were detected; the surface and air search areas have been derived from the former by float and current models. All to no avail.

One wonders if, in the eagerness to believe and the absence of any other lead, the authorities directing the search have ignored or downplayed evidence that is clearly contrary.

In the case of AF447 and also for the missing private plane piloted by billionaire Steve Fossett, faulty evidence led to the wrong areas being searched, with the loss of a year and a cost of over US$1 million.

A reporter on TV remarked: “Call it a triumph of science, or incredible luck, but on the very first path, the Ocean Shield (towing the TPL)... detected a steady series of pings.”[5] 

The prime minister of Australia was “very confident” that the signals were from the black box. One did hope that would be the case, but sadly it now appears to be incredible BAD luck creating a dead end that will take more weeks or months and millions of dollars to check out completely. – May 7, 2014.

Source notes:

1. email from P.H. Nargeolet to William Meacham April 24


3. email from Lee Freitag to William Meacham April 21

4. email from David Gallo to William Meacham April 23


Information about the three marine experts quoted:

* William Meacham is an archaeologist and writer affiliated with the University of Hong Kong.

* This is the personal opinion of the writer or publication and does not necessarily represent the views of The Malaysian Insider.


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