How much shock (force) can this beacon withstand on impact?

Is there an FAA certification telling us anything about it?

  • $\begingroup$ It seems to be behind a paywall. The manufacturer says it complies with TSO-C121b, which says that it complies with SAE AS8045A. SAE wants USD 74 for the document. $\endgroup$
    – Pondlife
    Commented Jul 7, 2016 at 1:36
  • $\begingroup$ "The rules governing underwater locator beacons are the Federal Aviation Administration (FAA) TSO-C121, C121a, and C121b. European Aviation Safety Agency (EASA) is expected to publish ETSO requirements that parallel the FAA standards." (Source). C121b extends the life to 90 days. CVR themselves are tested at 3,400 G (6.5 ms, half-sine shock wave), the ULB must at least sustain this. $\endgroup$
    – mins
    Commented Jul 7, 2016 at 8:05

1 Answer 1


An exact model is too specific to find, but the FAA Advisory Circular 21-10A regarding ULD's from 1983 says:

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There is also a patent from 1989 which lists specifications regarding most pingers:

Most pingers are cylindrical in shape. Typical dimensions for flight recorder applications are 1.25 inches in diameter and 3.8 inches long. The flight recorder ULDs can survive crash forces of 6000 g's (0.5 ms) and ocean depths of 20,000 feet.

Google Patents (1989)

The FAA also mentions the SAE International’s Aerospace Standard (AS) 8045a, Minimum Performance Standard for Underwater Locating Devices, which is behind a paywall. But the aforementioned AC should suffice.


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