The Standard Airport Traffic Pattern

The standard airport traffic pattern is a typical feature of the general aviation, and of aviation, generally, as well. A standard airport traffic pattern is a rectangular, flight track, at a given altitude and axed unto a runway. The traffic pattern allows for the departures from and the arrival to, an airport. On a non-controled terrain, the airport traffic pattern allows for a regulation of the planes arriving at or departing from the terrain, as on larger airports -and even on most large ones- the airport traffic pattern remains a usual reference. The traffic pattern, on another hand, is one the basic components of the GA pilot's training. The pilot-apprentice will intensively fly traffic patterns, as a way to learn the automaticity and the swiftness necessary to maneuvers in an airport environment, as confirmed pilots will always practice some patterns like a way to maintain their proficiency

. The Traffic Pattern like a Training Feature . The traffic pattern like a way to Get Inserted into an Airport's Environment, or to Leave a Terrain

The Traffic Pattern like a Training Feature

click on the picture to a view of the standard airport traffic pattern

Training along a traffic pattern is allowing a pilot-apprentice to gain the necessary automatisms and swiftness for flying in an airport environment. The traffic pattern (see the illustration) is a rectangular flight pattern, axed unto a runway and which has to be flown according to specific rules and techniques. As a GA pilot is training for his PPL, he will fly successive traffic patterns. Once airborne, the pilot will fly to the pattern's altitude as he keeps flying on the runway's axis. This part of the pattern is called the 'headwind leg', as the various segments of the pattern are called 'legs', each one, with its own name. The pilot then is turning into the following leg -the crosswind leg that is. The following one is the famed 'downwind leg', which itself is followed by the 'base leg'. The base leg is bringing the plane to the 'final', which is the last leg of the traffic pattern, bringing back to the runway. Any traffic pattern is linked to a runway. Any pattern -as it's a custom in the aviation world- is flown 'left-hand', which means that it's flown turning left. Some traffic patterns have to be flown 'right-hand' to take into consideration that some obstacle or relief is hindering one side of the terrain. A traffic pattern is usually flown at an altitude of about 800-900 ft above ground level (AGL). Here is how one' flying a traffic pattern: you will first take off from the active runway and climb to the pattern's altitude (say 800 ft) through the first two legs (with a climb, then a level, configuration for the plane). Once in downwind, you'll have to configure the plane for landing. Then you'll be turning into the base leg and, from there, into the final, where you'll fly down to the runway. Once landed, further, one won't perform a complete landing and vacuate the runway, as you'll fly what's called a 'touch-and-go'. A touch-and-go consists in that you land the plane completely, until the front wheel touches down as, instead of braking then you'll take off two notches of flaps, throttle back and take off again! Thus, doing a touch-and-go will allow you to begin another pattern (back to climb in runway's axis, level, downwind -preparing the plane for landing, base leg, final) and... another touch-and-go. With a third pattern! Once weathered, you'll be able to fly three of four pattern in a row! Attaining there is relatively difficult as you'll well catch what we mean by saying that the pattern is enhancing your skills in term of automatisms and swiftness! If your skills are on the rise only, begin by mastering the take offs and landings well enough and get into the pattern training only when you deem that you have a good control enough of those techniques (generally, for the pattern training, I presume that you master the technique of the take off and landing -see the tutorial '"Take Off and Landing in a GA Plane')

Let's get some more into the details! Let's take a training plane, like the Cessna 172SP, put it on the active runway on a terrain, and an average weather. Once in the plane, on the active, you'll configure it quickly for a take off, with a notch of flaps, trimming for take off, full mixture, 1000 rpm, pitot heat ON, beacon/strobe ON, landing lights ON, fuel pump ON. You'll take note of the runway's heading: runways are numbered through an abreviation of their magnetic heading, with, if the runway at a 171 heading, for example, it's numbered '17', or if at a 177, '18'. Just memorize that approximation as it's enough for the pattern training. Just get too the terrain's altitude through the pressure (you'll have taken in the weather panel) you'll have displayed into the altimeter. Let's suppose that the active is the runway 17, as the terrain's altitude is 1,620 ft. So, we'll take off from the runway 17, and, through a climb in the runway's axis, and after a left turn, we'll aim 1,620 - 900 equals 2,520 ft. At 500 ft AGL, fuel pump OFF. Whatever the altitude you reached, just turn few after into the crosswind leg (as we were flying at a 170 heading, 170+90=80, one turns down to a 080 heading. The level usually occurs in this crosswind leg as you set the plane level (visual clue, trim, etc.) and configure it (pitot heat OFF, landing lights OFF) and let the plane accelerate. Just look left, you see the runway. Soon after a new turn, which brings you into the downwind leg: 80+90=350, a 350 heading (this time, we crossed North, coming back to negative headings). We're now at a heading the reverse of the runway's (170/350). We're flying parallel to the active! There, much work! In such a few time, we'll have to have the plane configured for landing! Just take the throttles full OUT, maintaining the altitude and the heading, as the plane will slow. At 80 kts (see the specs for the plane you'll use; the values here are for a Cessna 172SP), throttle back to about 2,300 rpm -or the value to maintain 80 kts. One notch of flaps. Trim. Maintain the altitude (2,520 ft), and the heading (170). Further (and you see what the workload is!), configuring the plane for landing, according to the usual pattern for such a configuration (see, for example, the section 'Boarding and Engine Start' in the tutorial 'The Steps of a Flight in a GA Plane'): pilot's seat belt: FASTENED, passengers' (if any) seat belt: FASTENED; flaps 1: CHECKED; trim is OK; both tanks; not brakes; full mixture; carburetor heat ON; pitot heat ON, strobe ON, beacon ON (in FS2002 strobe and beacon, for the Cessna 172SP are not dissociable), landing lights ON, fuel pump ON. The heading indicator is re-calibrated to the magnetic compass; the alternator is charging (see the amperemeter). You see how such a series of actions has to be swift as, meanwhile the runway, to our left, have moved! Seen in perspective, we're about to get the runway's threshold in the extension of our wing. One more notch of flaps! And now, preparing to turn into the base left. This is done by taking like a mark the moment when the runway's threshold (or the landing point in case of a displaced threshold) is seen at 45 degrees behind! There we are... Let's turn! 350+90=260. A 260 heading... and we are in the base leg, as the runway now is ahead, left. We'll keep flying on the base leg until that we assess visually that it's time to turn into the final. The runway's axis approaching. Let's turn! We are aligned (hem!) with the runway and, immediately we get: full flaps and the descent pitch (visual clue, etc.). We just are descending now, ready to land! Adding to the difficulties of the pattern, you'll note that we had too, to radio. Once the plane configured in the downwind -before the second notch of flaps- we radioed that we were on the downwind, readying for a landing on the active ('Romeo-X-ray downwind for the runway 1-7' -such a wording for a non-controled terrain; this com makes that the other planes in the terrain's surroundings -or pattern- do know now where we are and what our intentions are). Then in the base leg ('Romeo-X-ray, base left for the 1-7') as, eventually, in final ('Romeo-X-ray, final for the 1-7'). Back to the final. Arriving to the runway. Flare! Throttle full out, slight pitch and... touching donw! BUT, instead of braking, back to airborne. 2 notches of flaps out (back to one for take off) and full throttle back! The 55 kts limit for take off are quickly back and take off again! Level, accelerating to 70 kts -our climb speed- the notch of flaps OUT and... climbing. And we do perform a new traffic pattern (fuel pump OUT at 500 ft AGL, etc.). Just practice at your pace! And don't get tired or disillusioned by the task. Just catch that: climb, turn, level, the runway, turn, downwind (slow, configure, radio), 45° rear, turn into the base leg (radio), the runway axis, turn into final (radio and descent)! Practice, practice!

The traffic pattern like a way to Get Inserted into an Airport's Environment, or to Leave a Terrain

Once you're mastering the traffic pattern, you'll see that it's too used to get into an airport's environment as, when arriving to a terrain (or getting there back after some training), the traffic pattern (above all for the non-controled terrain) is the conclusion of the approach, with our flight passing from the approach to the pattern, on which we'll configure the plane for landing. Various transitions are used to get into a pattern as the simplest are the easiest. On your descent, on the approach, you'll aim the traffic pattern's altitude and a point of it, depending on the direction from which you're flying from. Should your heading bring you onto the side of the downwind leg, just turn into it when you are at the appropriate distance from the runway. Should you reach the pattern on the opposite side, just get into the pattern through the crosswind leg, as, if you're heading to about the direction of the runway's heading, just fly what is called a 'long final', with the plane's downwind configuration made sufficiently ahead of the final proper (you'll radio then that you're 'on a long final for the runway 1-7') and, coming at the final's beginning, full flaps and descent pitch, etc.

The traffic pattern, at last, may be used, above all on the non-controled terrains, to leave from there, with the pilots flying some part of the pattern before turning to their route's heading and climbing. Departing from a runway 17, with a left-hand pattern, to a course's heading West, brings to fly the pattern up to the middle of the downwind and then turn left and fly, climbing, above the terrain's center. Leaving to a course East, will bring you the same (the middle of the downwind) and then turn right, as if you depart North, you'll have to fly the downwind completely, or South, to depart in the runway axis (and in this case, not using the pattern)

Remember, at last, that the airport patterns are left-handed by default, as some are right-handed. This is then indicated through the charts, or the signals area. Also, a good idea, along your exercises, will surely be to train for both