UPDATE 5/21/14: The families of missing MH370 passengers have released a fascinating document presenting their own analysis of the preliminary report issued by the Malaysian government’s Ministry of Transport, including their own assessment of what we know and what we’d like to know. Link: Analysis of the Preliminary Report on MH370 Incident, May 20 2014
by Michael Exner
[Note: The totality of what we know about the fate of missing Malaysia Airlines Flight 370 consists of a series of electronic handshake “pings” that were received by an Inmarsat satellite in the hours before the plane disappeared for good. Unfortunately, the authorities have steadfastly refused to release the full data set to the public, and there is an ongoing dispute between Inmarsat and Malaysia as to who exactly has the data and who is authorized to release it. According to CNN, a source within Inmarsat has said that the company released satellite ping data amounting to just 14 numbers to Malaysian authorities, along with documentation explaining their methods for analyzing the data. Here Michael Exner, Chairman of the Board of Radiometrics Corporation, weights in on that claim. — Jeff Wise]
In fact, we know there are at least 51 numbers, and here’s why. The BFO chart [released on March 25 by the Malaysian government as page two of “Annex I” accompanying the Inmarsat report — ed] shows 12 times and 12 frequencies. That’s 24 numbers.
Then, on April 29, there was a photo in Beijing that showed that there were more handshakes, and ACARS messages that preceded the first handshake on the BFO chart, but there were no BFO values given in the Beijing meeting with the families. But the fact that they had the angles proves they had the times and the BFO values. Thus, we know of at least 17 events for which they have Time, BFO and Angle (or time delays). That is 51 numbers total.
We have assembled the following data from two sources. The “BFO Data” provided in the March 25th AAIB ANNEX I Chart and the photo taken in Beijing on April 29, 2014.
Note that the numbers above represent our best estimates based on digitized paper graphs and photos. The true resolution is less than that inferred by the number of digits. Apparently, the statements about “…only 14 numbers…” are in reference to the last 7 BFO frequencies and last 7 elevation angles, which the official investigation team is focused on. But all the data from the other events are also valuable for the calibration of the other data. Those first 10 events are also very important.
Until April 29, 2014, it was believed that there were only 12 events recorded. The BFO chart has only 12 events. Then the photo taken of a chart projected on the wall in Beijing on 2014-04-29 showed that they had more data than previously known. That immediately raised the question, why didn’t they disclose all the data sooner, instead of only the 12 events disclosed on March 25, 2014? How much more do they have that has not been disclosed?
The photo proves that there were at least 17 total recorded handshake/ping events. For each event, there was a time, a BFO value and a time delay (elevation angle). It is important to note that elevation angle is NOT an observable parameter. It is a derived value, based on a time delay observation. The elevation angles are calculated from the time delays and several assumptions about the geometry of the earth, etc. So elevation angles are not raw data. They are derived products that depend on data and assumptions. We prefer the raw data, not Inmarsat’s derived work products.
In addition, there were 12 “Predicted North” and 12 “Predicted South” BFO values.
The missing metadata is really important. It’s more important than filling in the missing numbers. The existing BFO data in particular is very arcane and ambiguous. Without much better descriptions of what the BFO values mean, experts are guessing. Experts are even arguing over the question of whether the BFO values need to be interpreted as positive or negative Doppler values because the document is silent on that critical question. Another example of the missing metadata is a clear explanation of the so called Predicted Track data. It has everyone totally confused.
To Richard Quest: No one thinks there are reams of data. But there are more numbers than 14, as the description above clearly demonstrates. All we want are the missing numbers, and a clear explanation of how to interpret the BFO values (metadata). We also want the raw time delay values, not derived angles. And we want the numbers in a tabular, numeric format, not graphs designed for the general public. This what we mean by “give us all the data.”