Rectangular Course Technique 9-14 the helicopter and watching for other aircraft in the vicinity.  Other examples of ground reference maneuvers are flights  for photographic or observation purposes, such as pipe line  or power line checks. Prior to each maneuver, a clearing turn  should be done to ensure the area is free of conflicting traffic. line and maintain a specific heading, aircraft heading must be  adjusted in order to compensate for the winds and stay on the  proper ground track. Also, keep in mind that a constant scan  of flight instruments and outside references aid in maintaining  proper ground track.  Although the rectangular course may be entered from any  direction, this discussion assumes entry on a downwind  heading.  [Figure 9-15]  while approaching the field boundary  on the downwind leg, begin planning for an upcoming turn.  Since there is a tailwind on the downwind leg, the helicopter’s  groundspeed is increased (position 1). During the turn, the  wind causes the helicopter to drift away from the field. To  counteract this effect, the roll-in should be made at a fairly  fast rate with a relatively steep bank (position 2). This is  normally the steepest turn of the maneuver. The rectangular course is a training maneuver in which the  ground track of the helicopter is kept equidistant from the  sides of a selected rectangular area. While performing the  maneuver, the altitude and airspeed should be held constant.  The rectangular course helps develop recognition of a drift  toward or away from a line parallel to the intended ground  track. This is helpful in recognizing drift toward or from an  airport runway during the various legs of the airport traffic  pattern and is also useful in observation and photographic  flights. As the turn progresses, the tailwind component decreases,  which decreases the groundspeed. Consequently, the bank  angle and rate-of-turn must be reduced gradually to ensure  that upon completion of the turn, the crosswind ground track  continues to be the same distance from the edge of the field.  Upon completion of the turn, the helicopter should be level  and crabbed into the wind in order to maintain the proper  ground track. Keep in mind that in order to maintain proper  ground track the helicopter may have to be flown almost  sideways depending on the amount of wind. The forward  cyclic that is applied for airspeed will be in the direction of  the intended flight path. For this example, it will be in the  direction of the downwind corner of the field. However, since  the wind is now pushing the helicopter away from the field,  establish the proper drift correction by heading slightly into  the wind. Therefore, the turn should be greater than a 90°  change in heading (position 3). If the turn has been made  properly, the field boundary again appears to be one-fourth  to one-half mile away. While on the crosswind leg, the wind  correction should be adjusted, as necessary, to maintain a  uniform distance from the field boundary (position 4). Maintaining ground track while trying to fly a straight line  can be very difficult for new pilots to do. It is important to  understand the effects of the wind and how to compensate  for this. For this maneuver, pick a square or rectangular  field, or an area bounded on four sides by section lines or  roads, with sides approximately a mile in length. The area  selected should be well away from other air traffic. Fly the  maneuver approximately 500 to 1,000 feet above the ground  as appropriate. If the student finds it difficult to maintain a  proper ground track at that higher altitude, lower the altitude  for better ground reference until they feel more comfortable  and are able to grasp the concept better. Altitude can be raised  up to 1,000 feet as proficiency improves. Fly the helicopter parallel to and at a uniform distance, about  one-fourth to one-half mile, from the field boundaries, and  not directly above the boundaries. For best results, position  flightpath outside the field boundaries just far enough away  that they may be easily observed from either pilot seat by  looking out the side of the helicopter. If an attempt is made  to fly directly above the edges of the field, there will be no  usable reference points to start and complete the turns. In  addition, the closer the track of the helicopter is to the field  boundaries, the steeper the bank necessary at the turning  points. The edges of the selected field should be seen while  seated in a normal position and looking out the side of the  helicopter during either a left-hand or right-hand course. The  distance of the ground track from the edges of the field should  be the same regardless of whether the course is flown to the  left or right. All turns should be started when the helicopter is  abeam the corners of the field boundaries. The bank normally  should not exceed 30°–45° in light winds. Strong winds may  require more bank. As the next field boundary is being approached (position 5),  plan for the next turn. Since a wind correction angle is being  held into the wind and toward the field, this next turn requires  a turn of less than 90°. Since there is now a headwind, the  groundspeed decreases during the turn, the bank initially must  be medium and progressively decrease as the turn proceeds.  To complete the turn, time the rollout so that the helicopter  becomes level at a point aligned with the corner of the field  just as the longitudinal axis of the helicopter again becomes  parallel to the field boundary (position 6). The distance from  the field boundary should be the same as on the other sides  of the field. The pilot should understand that when trying to fly a straight 