On Sun, 29 Jan 2006 10:48:41 -0600, "Jim Macklin"
wrote:

At night, with no horizon and no moon you have actual
instrument conditions.

FWIW, according to the old FAQ,

"I agree with your statement that just because a person is flying “. .
.. by sole reference to instruments . . .” has nothing to do with
whether the flight can be logged as “actual instrument time” or
“simulated instrument time.” Only the weather conditions establish
whether the flight is in “actual instrument conditions.” And that is
dependent on the weather conditions where the aircraft is physically
located and the pilot makes that determination as to whether the
flight is in “actual instrument conditions” or he is performing
instrument flight under “simulated instrument conditions.” But for a
“quick and easy” answer to your question, it was always my
understanding if I were flying in weather conditions that were less
than the VFR weather minimums defined in § 91.155 and I was flying
“solely by reference to instruments” then that was the determining
factor for being able log instrument flight under “actual instrument
conditions.”

Otherwise, if I were flying solely by reference to instruments in VMC
conditions then I would log it as instrument flight in “simulated
instrument conditions.” In your example, the flight is clear of clouds
and in good visibility conditions at night over the desert with an
overcast above and no visible horizon. But other examples could
include flight between sloping cloud layers or flight between layers
of clouds at night. These could equally meet the requirement for
operations that can only be accomplished solely by reference to
instruments. But, the lack of sufficient visual reference to maintain
aircraft control without using instruments does not eliminate the
possibility of collision hazard with other aircraft or terrain."