Inmarsat log file message data at 17:07:34 UTC

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Originally, I thought I had found an anomaly in the Inmarsat MH370 Data Communication Logs file that was released, at time 17:07:34 UTC.

But upon further examination of the surrounding data, I think I can explain the anomaly and disregard it.

In my Method of calculating MH370's distance from satellite post, I showed a diagram and formulas for how to calculate MH370's distance from the Inmarsat 3F1 satellite.

I extracted only the following message types from the original data file, and only for cases where these messages were one after the other (i.e. no other messages occurred between them):

0x22 - Access Request (R/T-Channel)
0x51 - T-Channel Assignment

At 17:07:34 UTC, the delta time between the messages was 0.020 seconds less than it was for all previous messages of this same type. The delta time was also less than the minimum calculated round trip time.

The minimum calculated round trip time is based on MH370's known Slant Range to the satellite and the Perth GES 305's known Slant Range to the satellite at 17:07:34. But, the 0x62 message before the 0x22 message took 0.020 seconds longer than previous ones, so that might explain this time anomaly.

I was originally going to include all of the data from my calculations in this post, but because I no longer believe there is anything of interest with this data point at 17:07:34 UTC, the anomaly issue is now moot.

I made this blog post for completeness, because I had mentioned this on The Guardian.