Private Pilot Flight Training and Instruction Flight Training Article Library | Back To 4VFR.COM Rectangular Patterns Under calm conditions almost any rectangle can be used. If there is a wind, the longest leg of the rectangles should be planned to be crosswind. The less wind there is the lower the altitude flown so wind effect and crab angle is more discernible. This gives greater practice in selecting the crab angle needed to hold a given ground track. The ground track should held a constant distance outside the rectangle sides and around the corners. Usually only a couple of left turn rectangles are needed before doing a course reversal and entering two or more right turns. It is again important to do as many left turns as right turns. In the beginning accept some variation of altitude and tracking distance. On the second and any subsequent lessons be very specific and critical of variations. Do this because ground reference is one of the skill lessons that require mastery. Mastery will allow the pilot to maneuver about an airport pattern on track and at altitude. This skill must exist to allow sufficient intellectual energy left over for radio and reconfiguration of the aircraft for landing. The rectangular pattern should be flown as though the runway is parallel with the opposite side of the field. In calm winds heading and course are the same. It is in crosswinds where we use the ground reference skills of heading/course differences to make a desired ground track. The ideal of flying a pattern is that it be kept rectangular and tight to the airport. Properly flown the airport traffic pattern provides maximum safe separation of aircraft in the pattern, arriving aircraft and departing aircraft. The corners of a ground reference rectangle exactly conform to the four wind quadrants of the ground reference circle. The execution of the downwind and upwind turns are performed exactly the same for the rectangle as for the circle. Downwind straight legs will have crab angles between ground track (course) and heading to compensate for wind effect. Rectangular patterns are flown to the outside of a selected rectangle so as to give smooth turns at the corners. For best wind correction practice make the long side of the rectangle 90° to the wind. course reversal entry direction wind wind correcting headings It is important that the student be aware that flying the rectangular pattern has a direct relationship with the typical traffic pattern scenario. A low time pilot in the low and relatively slow pattern speed is more likely to be turning final too late. The bank angle seems steeper because the turn radius is tighter at slow speed. When the final approach line is overshot, rather than make the apparently steep turn even more so, the pilot hastens the turn with rudder. This rudder application while increasing the rate of turn will cause the nose to drop. The back pressure is added to lower the pitch, the speed drops, and aileron is trying to decrease the bank angle. At stall the airplane will roll to the inside of the turn and spin with the rudder. All of the stall symptoms are the result of sensory illusions too real to be recognized or corrected. It is too low and too late, you're dead. The purpose of rectangular patterns is to teach the student that the turns around a pattern must be planned, adjusted, and shaped with their straight legs to prevent the initial cause of the accident above. You must be able to position the aircraft on to the final approach course without overshooting. Or, if overshooting, the bank must not be increased nor the airspeed allowed to drop. You should learn to use "sum of the digits" in than all four headings at 90 degrees from each other are equal. Using the four cardinal headings we see that the sum of the digits for every 90, 180, or 270 degrees are always equal. North 3 + 6 + 0 = 9 East 0 + 9 + 0 = 9 South 1 + 8 + 0 = 9 West 2 + 7 + 0 = 9 This is also true for headings at 90 degrees to each other as with 045, 135, 225, 315 Written by Gene Whitt Flight Training Article Library | Back To 4VFR.COM