Enter�
 

Start Turn� Pattern
At Boundary No Crab 

Turn More Than�
 

90°—Roll Out� Complete Turn�
With Crab Established At Boundary Turn More� 

Than 90°
Complete Turn� At Boundary
Start Turn� At Boundary
Crab Into�
 

Crab Into� WIND Wind

Wind
 

Turn less Than� Start Turn� 90°—Roll Out� At Boundary With Crab Established
Complete Turn�
Turn Less� At Boundary
Than 90°
 

Start Turn� At Boundary
Complete Turn�
At Boundary

No Crab
Figure 9-15. Rectangular course. The numbered positions in the text refer to the numbers in this illustration. 

downwind heading. [Figure 9-15] As you approach the field boundary on the downwind leg, you should begin planning for your turn to the crosswind leg. Since you have a tailwind on the downwind leg, the helicopter's groundspeed is increased (position 1). During the turn onto the crosswind leg, which is the equivalent of the base leg in a traffic pattern, 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).
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 aligned with the downwind corner of the field. However, since the crosswind is now pushing you away from the field, you must establish the proper drift correction by flying slightly into the wind. Therefore, the turn to crosswind 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).
As the next field boundary is being approached (position 5), plan the turn onto the upwind leg. Since a wind correction angle is being held into the wind and toward the field while on the crosswind leg, this next turn requires a turn of less than 90°. Since the crosswind becomes a headwind, causing the groundspeed to decrease during this turn, the bank initially must be medium and progressively decreased 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.