The level-off from a glide must be started before reaching the  desired altitude because of the airplane’s downward inertia.  The amount of lead depends on the rate of descent and what  airspeed is desired upon completion of the level off. For  example, assume the aircraft is in a 500 fpm rate of descent,  and the desired final airspeed is higher than the glide speed.  The altitude lead should begin at approximately 100 feet  above the target altitude and at the lead point, power should  be increased to the appropriate level flight cruise power  setting when the desired final airspeed is higher than the glide  speed. At the lead point, power should be increased to the  appropriate level flight cruise power setting. The airplane’s  nose tends to rise as airspeed and power increases and the  pilot must smoothly control the pitch attitude so that the  level-off is completed at the desired altitude and airspeed.  When recovery is being made from a gliding turn, the back  pressure on the elevator control, which was applied during  the turn, must be decreased or the airplane’s nose will pitch  up excessively high resulting in a rapid loss of airspeed. This  error requires considerable attention and conscious control  adjustment before the normal glide can be resumed. These three factors make it necessary to use more back  pressure on the elevator than is required for a straight  glide or a level turn; and therefore, have a greater effect on  control coordination. In rolling in or out of a gliding turn,  the rudder is required to compensate for yawing tendencies;  however, the required rudder pedal pressures are reduced as  result of the reduced forces acting on the control surfaces.  Because the rudder forces are reduced, the pilot may apply  excessive rudder pedal pressures based on their experience  with powered flight and overcontrol the aircraft causing slips  and skids rather than coordinated flight. This may result in a  much greater deflection of the rudder resulting in potentially  hazardous flight control conditions. Common errors in the performance of descents and  descending turns are: Some examples of this hazard: Level-off from a glide is really two different maneuvers  depending on the type of glide: 3-22 • The normal stability and inherent characteristics of  the airplane to nose-down with the power off • A low-level gliding steep turn during an engine failure  emergency. If the rudder is excessively deflected in  the direction of the bank while the pilot is increasing  elevator back pressure in an attempt to retain altitude,  the situation can rapidly turn into an unrecoverable spin. • During a power-off landing approach. The pilot  depresses the rudder pedal with excessive pressure that  leads to increased lift on the outside wing, banking  the airplane in the direction of the rudder deflection.  The pilot may improperly apply the opposite aileron  to prevent the bank from increasing while applying  elevator back pressure. If allowed to progress, this  situation may result in a fully developed cross-control  condition. A stall in this situation almost certainly  results in a rapid and unrecoverable spin. • Failure to adequately clear for aircraft traffic in the  turn direction or descent.  • Inadequate elevator back pressure during glide entry  resulting in an overly steep glide. • Failure to slow the airplane to approximate glide speed  prior to lowering pitch attitude. • Attempting to establish/maintain a normal glide solely  by reference to flight instruments. • Inability to sense changes in airspeed through sound  and feel. • Inability to stabilize the glide (chasing the airspeed  indicator). • Attempting to “stretch” the glide by applying back- elevator pressure. • Skidding or slipping during gliding turns due to  inadequate appreciation of the difference in rudder  forces as compared to turns with power. • Failure to lower pitch attitude during gliding turn entry  resulting in a decrease in airspeed. • Excessive rudder pressure during recovery from  gliding turns. • Inadequate pitch control during recovery from straight  glide. 2. In the case of a quicker descent or simulated power  failure training, power should be applied as the 10%  lead value appears on the altimeter to allow a slow  but positive power application to maintain or increase  airspeed while raising the nose to stop the descent. Retrim as necessary.  1. In the event of a complete power failure, the best glide  speed should be held until necessary to reconfigure for  the landing, with planning for a steeper approach than  usual when partial power is used for the approach to  landing. A 10 percent lead (100 feet if the decent rate is  1,000 feet per minute) factor should be sufficient. That  is what is given in the Instrument flying Handbook,  so that should be the general rule of thumb for all  publications.