TM  55-1510-221-10 9-13. LOSS OF PRESSURIZATION (ABOVE 10, 000  FEET). If  cabin  pressurization  is  lost  when  operating above  10,000  feet  or  the  ALT  WARN  warning annunciator  light  illuminates,  perform  the  following: 1. Crew oxygen masks - 100% and on. 9-14. CABIN DOOR CAUTION LIGHT ILLUMI- NATED. Remain clear of cabin door and perform the fol- lowing: 1. Bleed air valve switches - ENVIRO OFF. 2. Descend below 14,000 feet as soon as practi- cable. 3.  Oxygen  -  As  required. 9-15.  SINGLE-ENGINE  DESCENT/ARRIVAL. NOTE Approximately  85%  N1  is  required  to maintain  pressurization  schedule. Perform  the  following  procedure  prior  to  the final descent for landing. 1. Cabin controller - Set. 2. Ice and rain switches - As required. 3.  Altimeters  -  Set. 4. Recognition lights - ON. *  5. Arrival briefing - Complete. 9-16. SINGLE-ENGINE BEFORE LANDING. 1. Propeller lever - As required. NOTE During approach, propeller should be set at 1900 RPM to prevent glideslope inter- ference   (ILS   approach),   provide   better power  response  during  approach,  and  to minimize  attitude  change  when  advancing propeller levers for landing. 2.   Flaps   -   APPROACH. 3.  Gear  -  DN. 4. Landing lights - As required. 9-8 5.  Yaw  damp  -  OFF. 6.  Brake  deice  -  OFF. 9-17. SINGLE-ENGINE LANDING CHECK. Perform  the  following  procedure  during  final approach to runway. 1. Autopilot/yaw damp - Disengaged. 2. Gear lights - Check (three green). 3.  Propeller  lever  (operative  engine)  -  HIGH RPM. NOTE To insure constant reversing characteris- tics, the propeller control must be in the HIGH  RPM  position. 9-18. SINGLE-ENGINE GO-AROUND. The  decision  to  go  around  must  be  made  as early as possible. Elevator forces at the start of a go- around are very high and a considerable amount of rudder  control  will  also  be  required  at  low  airspeeds. Retrim as required. If rudder application is insuffi- cient, or applied too slowly, directional control can- not be maintained. If control difficulties are experi- enced,  reduce  power  on  the  operating  engine immediately. Insure that the aircraft does not touch the  ground  before  retracting  the  landing  gear. Retract  the  flaps  only  as  safe  airspeed  permits (TAKEOFF  until  V  ref,  then  UP). engine go-around as follows: Perform single- Once  flaps  are  fully  extended,  a  single- engine   go-around   may   not   be   possible when  close  to  the  ground  under  condi- tions  of  high  gross  weights  and/or  high density  altitude. 1. Power - Maximum allowable. 2.  Gear  -  UP. 3. Flaps - As required. 4.  Landing  lights  -  OFF. 5.  Power  -  As  required. 6. Yaw damp - As required.