Air taxi (100 feet or less) Faster travel Surface taxi Less rotor downwash Figure 9-11.  Surface taxi. Figure 9-10.  Air taxi. Surface Taxi Technique Technique Common Errors Common Errors A surface taxi is used to minimize the effects of rotor  downwash in wheel-type helicopters.  [Figure 9-11]  Surface  taxiing in skid type helicopters is generally not recommended  due to the high risk of dynamic rollover; for more information,  refer to Chapter 11, Helicopter Emergencies and Hazards. Before starting, determine the appropriate airspeed and  altitude combination to remain out of the cross-hatched or  shaded areas of the height/velocity diagram (see  Figure 7-1 ).  Additionally, be aware of crosswind conditions that could  lead to loss of tail rotor effectiveness. Pick out two references  directly in front of the helicopter for the ground path desired.  These reference points should be kept in line throughout the  maneuver. The helicopter should be in a stationary position on the surface  with the collective full down and the rpm the same as that  used for a hover. This rpm should be maintained throughout  the maneuver. Then, move the cyclic slightly forward and  apply gradual upward pressure on the collective to move  the helicopter forward along the surface. Use the antitorque  pedals to maintain heading and the cyclic to maintain ground  track. The collective controls starting, stopping, and speed  while taxiing. The higher the collective pitch, the faster the  taxi speed; however, do not taxi faster than a brisk walk. If  the helicopter is equipped with brakes, use them to help slow  down. Do not use the cyclic to control groundspeed. Begin the maneuver from a normal hovering height by  applying forward pressure on the cyclic. As movement  begins, attain the desired airspeed with the cyclic. Control the  desired altitude with the collective and rpm with the throttle.  Throughout the maneuver, maintain a desired groundspeed  and ground track with the cyclic, a constant heading with  antitorque pedals, the desired altitude with the collective,  and proper operating rpm with the throttle. During a crosswind taxi, hold the cyclic into the wind a  sufficient amount to eliminate any drifting movement. To stop the forward movement, apply aft cyclic pressure to  reduce forward speed. Simultaneously lower the collective to  initiate a descent to hover altitude. As forward motion stops,  return the cyclic to the neutral position to prevent rearward  movement. As approaching the proper hover altitude, increase  the collective as necessary to stop descent at hover altitude  (much like a quick stop maneuver (see page 10-4)). 1.  Improper use of cyclic. 2.  Failure to use antitorque pedals for heading control. 1.  Erratic movement of the cyclic, resulting in improper  airspeed control and erratic movement over the  surface. 2.  Failure to use proper antitorque pedal control, resulting  in excessive heading change. 3.  Failure to maintain desired altitude. 4.  Failure to maintain proper rpm. 5.  Overflying parked aircraft causing possible damage  from rotor downwash. 9-11 6.  Flying in the cross-hatched or shaded area of the  height/velocity diagram. 7.  Flying in a crosswind that could lead to loss of tail  rotor effectiveness. 8.  Excessive tail-low attitudes. 9.  Excessive power used or required to stop. 10. Failure to maintain alignment with direction of travel.