On May 5, 7:56*am, jcarlyle wrote:
The older Cambridge recorders (10, 20, 25) do use circular recording,
writing over the oldest data with the latest data without a hitch. If
you really want to erase all of the flight data, though, simply change
something like the Pilot Name or Comp ID.

I'd be surprosed if that erases any data although it may make it
inaccessible by the user. Typically "erasing" just moves a "pointer"
and all the data is still remains stored in memory.

Of course, as you say, there is no reason to "erase" these loggers.
Unlike some others they never fill up and they have no issues when
looping back to the start of memory.

The only issue I know with these loggers is that they produce an
inaccurate pressure altitude record when the voltage drops below
spec. Don't transmit at 17,400 ft during a contest or you may have to
explain an airspace violation. (the recorded altitude increases as the
voltage reduces).

Andy