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When flying straight and level and following a select - ed ground track, the preferred method of correcting for wind drift is to head the powered parachute suf- ficiently into the wind to cause the powered parachute to move forward into the wind at the same rate the wind is moving it sideways. Depending on the wind velocity, this may require a large wind correction an- gle or one of only a few degrees. When the drift has been neutralized, the powered parachute will follow the desired ground track. 

To understand the need for drift correction during flight, consider a flight with a wind velocity of 30 knots from the left and 90° to the direction the pow- ered parachute is headed. After 1 hour, the body of air in which the powered parachute is flying will have moved 30 NM to the right. Since the powered para - chute is moving with this body of air, it too will have drifted 30 NM to the right. In relation to the air, the powered parachute moved forward, but in relation to the ground, it moved forward as well as 30 NM to the right. 

There are times when the pilot needs to correct for drift while in a turn. [Figure 9-2] Throughout the turn the wind will be acting on the powered parachute from constantly changing angles. The relative wind angle and speed govern the time it takes for the powered parachute to progress through any part of a turn. This is due to the constantly changing groundspeed. When the powered parachute is headed into the wind, the groundspeed is decreased; when headed downwind, the groundspeed is increased. Through the crosswind portion of a turn, the powered parachute must be turned sufficiently into the wind to counteract drift. 

To follow a desired circular ground track, the wind correction angle must be varied in a timely manner because of the varying groundspeed as the turn pro- gresses. The faster the groundspeed, the faster the 

wind correction angle must be established; the slow- er the groundspeed, the slower the wind correction angle must be established. You will see then that the PPC should have the steepest bank and fastest rate of turn on the downwind portion of the turn and have the shallowest bank and slowest rate of turn on the upwind portion. 

The principles and techniques of varying the angle of bank to change the rate of turn and wind correc- tion angle for controlling wind drift during a turn are the same for all ground track maneuvers involving changes in direction of flight. 

When there is no wind, it should be simple to fly along a ground track with an arc of exactly 180° and a con- stant radius because the flightpath and ground track would be identical. This can be demonstrated by ap- proaching a road at a 90° angle and, when directly over the road, rolling into a medium-banked turn, then maintaining the same angle of bank throughout the 180° of turn. [Figure 9-2] 

To complete the turn, the rollout should be started at a point where the canopy will become level as the pow- ered parachute again reaches the road at a 90° angle and will be directly over the road just as the turn is completed. This would be possible only if there were absolutely no wind and if the angle of bank and the rate of turn remained constant throughout the entire maneuver. 

If the turn were made with a constant angle of bank and a wind blowing directly across the road, it would result in a constant radius turn through the air. How- ever, the wind effects would cause the ground track to be distorted from a constant radius turn or semicir- cular path. The greater the wind velocity, the greater would be the difference between the desired ground track and the flightpath. To counteract this drift, the 

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