What is it + How To: Flying a Rectangular Course
As we begin exploring ground reference maneuvers, we're going to take a few minutes to discuss the key elements of the rectangular course.
The goal of this maneuver is to make a rectangular track with the airplane around a selected reference on the ground by correcting for wind drift. As with all other maneuvers, the rectangular course has three main elements that the pilot needs to concentrate on, directional control, altitude control, and airspeed control.
In performing the rectangular course you will be flying your airplane across, with and against the wind it is important to understand where the wind is coming from so that you may correct for any wind drift through each leg of the rectangle. Since the airplane will be changing direction throughout this maneuver, the angle of bank required in order to maintain the desired ground track will also change. Since the airplane is being flown through four turns forming a rectangle along the ground on each leg of the maneuver, the airplane will have a different ground speed. On the first leg the downwind the airplane will have its highest ground speed since the airplane is traveling at its highest speed at this point. When the turn is made to the base leg, the steepest angle of bank and fastest roll rate must be used and should normally not exceed 45 degrees. By using a steeper bank angle you are able to maintain a smaller radius of turn. If the bank is too shallow, the airplane will end up with a wider turn radius. As the wind pushes the airplane away from your desired ground track.
Once the turn is complete the airplane will be on the base leg and the wind will be blowing across the side of the airplane. In a cross wind you will have to crab the airplane toward your reference field and into the wind in order to maintain your rectangular course along the ground. This means that instead of turning exactly 90 degrees from your downwind heading, you will have to change your heading a little bit more than 90 degrees. The amount of crab depends upon the strength of the wind. On a day with a higher winds, the crab angle may be greater than it would be on a day with calmer winds. In the second turn, since the airplane is no longer traveling with the wind, you will use a medium bank angle with a gradual reduction to shallow. As you turn into the wind it will not be necessary to turn to a full 90 degree since you were already crabbing towards your reference. This will align you parallel to the downwind leg you flew earlier and should place the airplane directly into the wind. Little to no drift correction should be required on this upwind leg.
As you approach your third turn, the airplane should be rolled slowly into a shallow bank angle. With the wind now pushing against the airplane, reducing your ground speed too steep of a bank will cause the airplane to drift towards your reference point. As the term progresses, the headwind component decreases and the ground speed of the airplane will increase. This will require you to gradually increase the angle of bank until you roll out of the turn. Similar to the base leg and the crosswind leg of the maneuver, the wind will be blown across the side of the airplane. This time, however, the wind will be pushing the airplane towards your reference instead of away from it. This means that you must roll out after less than 90 degrees of heading change in order to establish a crab into the wind. For the last turn towards the downwind leg, you should plan to turn the airplane more than 90 degrees in order to roll out on the original downwind heading. As the airplane is rolled into a medium bank turn, the ground speed will be increasing, requiring you to gradually increase the angle of bank. In order to maintain a constant radius of turn, the rollout should be timed so that the airplane ends up on the same heading and the same distance from the reference field as it was when the maneuver began on the downwind leg.
Throughout the maneuver it is important that you divide your attention both inside and outside the airplane in order to maintain a constant altitude. Using a combination of the horizon wingtips and instruments will help you keep your original altitude as you complete the rectangular course. The primary flight instrument you'll be using to control the pitch is the attitude indicator. Since the bank varies throughout the maneuver, the back pressure on the yoke will have to be increased when flying downwind where you use the greatest bank and decreased when flying upwind where you use the shallow bank back up the attitude indicator with your altimeter and VSI to maintain your altitude. If you lose or gain altitude make the appropriate pitch power adjustments but do not change the bank angle from what is required to complete the maneuver.
While performing the rectangular course it is important that you maintain a constant indicated airspeed. This will allow you to better anticipate the changes to your ground speed as the airplane travels with a beam or against the wind. If you maintain a constant power setting throughout the maneuver, your indicated airspeed should not change as the airplane changes the direction. However, the effects of airflow across the prop could cause small power changes in the engine, monitor your power setting throughout the maneuver, and make small adjustments as necessary to keep your airspeed constant.
Notes:
- To perform a rectangular course you must first determine the wind direction, use visual references such as smoke, lakes, flags, or even a wind drift circle in order to accurately determine where the wind is coming from. Once you know the wind direction you can begin to set up for the maneuver as with all maneuvers, perform clearing turns and make a position report.
- The call on the radio should be said in entering the course, said as: traffic (Station/Location/Airport) (Plane Identifier) over the fields west of (Airport/Location) northeast corner. Ground.
- In order to fly a rectangular course you will need a ground reference area. Select a rectangular area or an area bounded on four sides by filled edges or roads with lengths of approximately one mile. Be sure that you select an area in which an emergency landing can be made if necessary. Position the airplane so that you enter the maneuver on a 45 degree angle to the center of your downwind leg. This will allow you to begin the maneuver with the highest ground speed as you enter the downwind leg.
- Position the airplane at a distance from your field that places the edge about halfway up the wing strut of the aircraft. This will keep the aircraft about a half a mile from the reference point and will allow you to see the ground track throughout the maneuver.
- Once you turn onto the downwind, remember that your ground speed will be at its fastest as the airplane passes a beam or adjacent to the first corner of your fields. Begin your first turn by rolling at a fairly high rate to your steepest bank. This bank angle should be less than 45 degrees in normal conditions. Gradually reduce your bank angle to a medium bank as the ground speed decreases and roll out slightly more than 90 degrees of heading change in order to establish drift correction for the new crosswind. Once you come abeam your next corner, roll the airplane into a medium bank turn and slowly decrease the bank to shallow as the ground speed decreases. Remember, make less than 90 degrees of heading change to stay parallel to your field on the upwind leg. The reference line in the selected field should be about halfway up your wing. Strut along this leg to place you approximately a half a mile from the field.
End Goal/Skill Req:
- Select a suitable reference area that includes an emergency landing site within gliding distance in case of an engine failure.
- Plan the maneuver so that you enter either a left or right pattern 600 to 1 thousand feet AGL 45 degrees to the downwind leg around your reference area. -Apply wind drift correction during both straight and turning flight to maintain a constant ground track around your reference area.
- Divide tension between aircraft control and ground track.
-Will maintain a coordinated flight and maintain your altitude. Plus or -100 feet and airspe plus or -10 knots.
As we begin exploring ground reference maneuvers, we're going to take a few minutes to discuss the key elements of the rectangular course.
The goal of this maneuver is to make a rectangular track with the airplane around a selected reference on the ground by correcting for wind drift. As with all other maneuvers, the rectangular course has three main elements that the pilot needs to concentrate on, directional control, altitude control, and airspeed control.
In performing the rectangular course you will be flying your airplane across, with and against the wind it is important to understand where the wind is coming from so that you may correct for any wind drift through each leg of the rectangle. Since the airplane will be changing direction throughout this maneuver, the angle of bank required in order to maintain the desired ground track will also change. Since the airplane is being flown through four turns forming a rectangle along the ground on each leg of the maneuver, the airplane will have a different ground speed. On the first leg the downwind the airplane will have its highest ground speed since the airplane is traveling at its highest speed at this point. When the turn is made to the base leg, the steepest angle of bank and fastest roll rate must be used and should normally not exceed 45 degrees. By using a steeper bank angle you are able to maintain a smaller radius of turn. If the bank is too shallow, the airplane will end up with a wider turn radius. As the wind pushes the airplane away from your desired ground track.
Once the turn is complete the airplane will be on the base leg and the wind will be blowing across the side of the airplane. In a cross wind you will have to crab the airplane toward your reference field and into the wind in order to maintain your rectangular course along the ground. This means that instead of turning exactly 90 degrees from your downwind heading, you will have to change your heading a little bit more than 90 degrees. The amount of crab depends upon the strength of the wind. On a day with a higher winds, the crab angle may be greater than it would be on a day with calmer winds. In the second turn, since the airplane is no longer traveling with the wind, you will use a medium bank angle with a gradual reduction to shallow. As you turn into the wind it will not be necessary to turn to a full 90 degree since you were already crabbing towards your reference. This will align you parallel to the downwind leg you flew earlier and should place the airplane directly into the wind. Little to no drift correction should be required on this upwind leg.
As you approach your third turn, the airplane should be rolled slowly into a shallow bank angle. With the wind now pushing against the airplane, reducing your ground speed too steep of a bank will cause the airplane to drift towards your reference point. As the term progresses, the headwind component decreases and the ground speed of the airplane will increase. This will require you to gradually increase the angle of bank until you roll out of the turn. Similar to the base leg and the crosswind leg of the maneuver, the wind will be blown across the side of the airplane. This time, however, the wind will be pushing the airplane towards your reference instead of away from it. This means that you must roll out after less than 90 degrees of heading change in order to establish a crab into the wind. For the last turn towards the downwind leg, you should plan to turn the airplane more than 90 degrees in order to roll out on the original downwind heading. As the airplane is rolled into a medium bank turn, the ground speed will be increasing, requiring you to gradually increase the angle of bank. In order to maintain a constant radius of turn, the rollout should be timed so that the airplane ends up on the same heading and the same distance from the reference field as it was when the maneuver began on the downwind leg.
Throughout the maneuver it is important that you divide your attention both inside and outside the airplane in order to maintain a constant altitude. Using a combination of the horizon wingtips and instruments will help you keep your original altitude as you complete the rectangular course. The primary flight instrument you'll be using to control the pitch is the attitude indicator. Since the bank varies throughout the maneuver, the back pressure on the yoke will have to be increased when flying downwind where you use the greatest bank and decreased when flying upwind where you use the shallow bank back up the attitude indicator with your altimeter and VSI to maintain your altitude. If you lose or gain altitude make the appropriate pitch power adjustments but do not change the bank angle from what is required to complete the maneuver.
While performing the rectangular course it is important that you maintain a constant indicated airspeed. This will allow you to better anticipate the changes to your ground speed as the airplane travels with a beam or against the wind. If you maintain a constant power setting throughout the maneuver, your indicated airspeed should not change as the airplane changes the direction. However, the effects of airflow across the prop could cause small power changes in the engine, monitor your power setting throughout the maneuver, and make small adjustments as necessary to keep your airspeed constant.
Notes:
- To perform a rectangular course you must first determine the wind direction, use visual references such as smoke, lakes, flags, or even a wind drift circle in order to accurately determine where the wind is coming from. Once you know the wind direction you can begin to set up for the maneuver as with all maneuvers, perform clearing turns and make a position report.
- The call on the radio should be said in entering the course, said as: traffic (Station/Location/Airport) (Plane Identifier) over the fields west of (Airport/Location) northeast corner. Ground.
- In order to fly a rectangular course you will need a ground reference area. Select a rectangular area or an area bounded on four sides by filled edges or roads with lengths of approximately one mile. Be sure that you select an area in which an emergency landing can be made if necessary. Position the airplane so that you enter the maneuver on a 45 degree angle to the center of your downwind leg. This will allow you to begin the maneuver with the highest ground speed as you enter the downwind leg.
- Position the airplane at a distance from your field that places the edge about halfway up the wing strut of the aircraft. This will keep the aircraft about a half a mile from the reference point and will allow you to see the ground track throughout the maneuver.
- Once you turn onto the downwind, remember that your ground speed will be at its fastest as the airplane passes a beam or adjacent to the first corner of your fields. Begin your first turn by rolling at a fairly high rate to your steepest bank. This bank angle should be less than 45 degrees in normal conditions. Gradually reduce your bank angle to a medium bank as the ground speed decreases and roll out slightly more than 90 degrees of heading change in order to establish drift correction for the new crosswind. Once you come abeam your next corner, roll the airplane into a medium bank turn and slowly decrease the bank to shallow as the ground speed decreases. Remember, make less than 90 degrees of heading change to stay parallel to your field on the upwind leg. The reference line in the selected field should be about halfway up your wing. Strut along this leg to place you approximately a half a mile from the field.
End Goal/Skill Req:
- Select a suitable reference area that includes an emergency landing site within gliding distance in case of an engine failure.
- Plan the maneuver so that you enter either a left or right pattern 600 to 1 thousand feet AGL 45 degrees to the downwind leg around your reference area. -Apply wind drift correction during both straight and turning flight to maintain a constant ground track around your reference area.
- Divide tension between aircraft control and ground track.
-Will maintain a coordinated flight and maintain your altitude. Plus or -100 feet and airspe plus or -10 knots.