http://w3n-a.blogspot.com/2008/12/fl...-airspeed.html

This maneuver demonstrates the flight characteristics and degree of
controllability of the airplane at its minimum flying speed. By
definition, the term "flight at minimum controllable airspeed" means a
speed at which any further increase in angle of attack or load factor,
or reduction in power will cause an immediate stall. Instruction in
flight at minimum controllable airspeed should be introduced at
reduced power settings, with the airspeed sufficiently above the stall
to permit maneuvering, but close enough to the stall to sense the
characteristics of flight at very low airspeed—which are sloppy
controls, ragged response to control inputs, and difficulty
maintaining altitude. Maneuvering at minimum controllable airspeed
should be performed using both instrument indications and outside
visual reference. It is important that pilots form the habit of
frequent reference to the flight instruments, especially the airspeed
indicator, while flying at very low airspeeds. However, a "feel" for
the airplane at very low airspeeds must be developed to avoid
inadvertent stalls and to operate the airplane with precision.

http://w3n-a.blogspot.com/2008/12/fl...-airspeed.html