Pattern Discipline

Flying the landing pattern is one of those simple tasks that makes use of all the fundamentals of flying. It also uses other skills and disciplines–along with math and physics–and a “dash” of common sense.

The start of a good pattern begins a couple of miles away from the airport, maybe further. One of the more difficult tasks for new pilots is determining the heading to get into the pattern. Here is where the use of math comes to play.

If the runway in use is Runway 4 with a left pattern, 040 degrees is your runway heading, 040 – 180 = 220 for the downwind heading, and 220 – 90 = 130 on base leg, and the crosswind leg is 040 – 90 = 310, which actually becomes 040 – 90 = -50 + 360 = 310 (this is due to the 360 degree limitation). Now all you have to figure out is the entry leg, which is the downwind leg heading, less 45 degrees, or, 220 – 45 = 175.

Notice how all the math uses minus signs rather than plus signs. This is important: left traffic is minus because turning left always subtracts numbers on the compass card, while right patterns always use addition.  So, right hand traffic on Runway 4 uses the math like this: runway heading, 040 + 180 = 220; crosswind heading, 040 + 90 = 130; entry heading, 220 + 45 = 265.

Now here is another secret about all of the math above. Really, the only thing you have to know is the entry heading. When you determine the entry heading, you can draw a line on your sectional out from the center of the airport along the reciprocal of the entry heading. Next, pick a landmark along that line 3 to 5 nautical miles away from the airport. Go to that spot, point the nose of the airplane at the middle of the airport, and you will be perfectly set up for the proper entry to the pattern. After a while, you will get to the point that you can gauge where you need to be for that proper 45-degree entry to the downwind leg.

Once in the pattern, the trick to making good 90-degree turns regardless of the math is to look out the wing, pick a point on the horizon, and turn toward it putting the nose on the point. Essentially, if you are in the pattern for Runway 4 on the downwind leg approaching the base leg turn, all you have to do is look out to the left and pick a point just beyond the left wing. After turning to put the nose on that point, you will have made a 90 degree turn onto the base leg—no math required.

During the time you are flying the pattern, you should have the airplane’s speed reduced to a safe speed and the altitude roughly 800 to 1000 feet AGL, or whatever is mandated by the airport rules. Control of the airplane in the pattern is necessary; a good pilot will maintain altitude very close to the pattern altitude along with the speed near 10 knots of the desired pattern speed appropriate for the aircraft.

While disciplined control of airspeed is important in all phases of flight, it is critical in flying the final approach. Pilots must be on speed to execute the flare and landing properly. If too slow, there is a real possibility of stalling the wing on short final and impacting the ground prior to reaching the runway. Flying too fast can also result in similar catastrophe, only on the far end of the runway.

Speed control is a function of two pilot inputs: throttle position (or power) and pitch attitude (nose position). If the pilot is slow and high, the remedy is lowering the nose; the worst combination a pilot can attain is being low and slow, for which the pilot must increase power while carefully maintaining attitude and altitude to execute the go-around. If high and fast, the pilot should execute the go around appropriately, in order to avoid running off the far end of the runway, as in the case of the pilot in the YouTube video below.


(Found at https://www.youtube.com/watch?v=-z2o0ac.)

For the pilot who is flying final too fast, the first action required is a reduction of power. If low and fast, the pilot can use the excess speed to stabilize altitude until flying to the proper glideslope and can catch the correct airspeed with power or the proper pitch attitude.

If the pilot has flown the airplane to a point too high and fast on the final approach, the game is over for the most part. If the runway is excessively long, the landing might be salvageable. However, this could encourage a bad habit pattern. Correcting a high/fast on a long runway is an option, but on shorter landing strips, as shown in the video, inexperienced pilots who are in the habit of forcing the airplane down may be subject to running off the end the runway.

On every approach and landing, the PIC should choose a physical point on the runway at which the go-around commences if the aircraft is not on the runway and under control. If it is not, the pilot needs to abandon the landing and go-around immediately.

Ideally, pilots should be capable of arriving in the landing area at the precise speed. For normal landings, the transition from approach speed to touchdown requires a reduction in power (if not already at idle) and airspeed.  Contact with the runway should happen very close to stall with a nose up attitude.

After touchdown, one of the common mistakes made by lower time pilots is relaxing the elevator. Following touchdown and as the airplane slows, backpressure on the elevator should be maintained or increased as the airspeed decreases.

The pilot needs to maintain the backpressure throughout the landing rollout while turning the ailerons full in the direction from which the crosswind is blowing. At the end of every properly executed landing, the yoke or stick should be completely back and turned in the direction of the wind.

After completing the landing and with the airplane fully under control, the pilot then needs to position the flight controls appropriately for the wind conditions relating to taxiing. When the plane is back in the parking space, the pilot can finish “flying” the airplane when the mixture is pulled to idle cut-off.

For more on short field landings, see my blog on The Short Field Landing. For the soft field landing, see The Soft Field Landing.

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©2012 J. Clark

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