[manarth]

Here's a transcript of the intercepted call that they played:

> You have reached the 310 airlift squadron C-37 aircraft, tail number 0028.

> To call the CSL press 1.

> To call secure telephone number one, press 2.

> To call secure telephone number two, press <missing>

> Satcom direct Inmarsat connection in progress, please hold while we attempt to connect your call.

> The approximate global connect time is <missing>

> <ringing>

I suppose that selecting to connect to the secure phones could trigger an encryption layer on top of the call.