[Boatanchors] Radio transmitter ranges

[William L Howard]

I was asked by an overseas contact about US Army TMs use of the term
mile for a radios range  He asks " I  mean,  Is TM indication of "mile"
based on "land mile"  or  "sea mile" ????
One land mile is around 1.6Km. and One sea mile is around 1.8Km."

I would assume that means land mile but admit I could be wrong. Do any
of you know for certain which range is used?

Thanks,

Bill Howard