Convert from military pace to fathom [ancient]

Unit Definition (military pace)
The length of a single step in marching (taken to be 30 inches for quick time or 36 inches for double time).

Unit Definition (fathom [ancient])
A fathom is a unit of measure equal to 2 yards or 6 feet, or 1.8288 metres. The name of the unit derives from the Old English word fæthm meaning 'outstretched arms' which was the original definition of the unit's measure.