Airports vary in complexity from small grass or sod strips to major terminals having multiple paved runways and taxiways. Regardless of the type of airport, the pilot must know and abide by the rules and general operating procedures applicable to the airport being used. These rules and procedures are based not only on logic or common sense but also on courtesy, and their objective is to keep air traffic moving with maximum safety and efficiency. The use of any traffic pattern, service, or procedure does not alter the responsibility of pilots to see and avoid other aircraft.
Generally, there are two types of airport operations:
- Uncontrolled airports where there is no control tower
- Controlled airports where there is a control tower with an air traffic controller
Airport operations is a prerequisite for reading and understanding this chapter. The Pilot’s Handbook of Aeronautical Knowledge (FAA-H-8083-25) chapter on airport operations is the starting point for this subject. Additionally, the portions of the Aeronautical Information Manual (AIM) covering aeronautical lighting and other airport visual aids, airspace, and air traffic control, should be studied prior to reading this chapter.
The following airport patterns are applicable to both towered and nontowered airport operations; however, in nontowered airports the pilot should use the information presented in this chapter along with the references provided in the summary to coordinate with the other air traffic. When flying at towered airports, the principles must be understood to understand the air traffic controller’s instructions. The pilot is always responsible for “see and avoid” and must continually look for other aircraft in towered and nontowered operations.
Standard Airport Traffic Patterns
To assure that air traffic flows into and out of an airport in an orderly manner, an airport traffic pattern is established appropriate to the local conditions, including the direction and placement of the pattern, altitude to be flown, and procedures for entering and leaving the pattern. Unless the airport displays approved visual markings indicating that turns should be made to the right, pilots should make all turns in the pattern to the left.
When operating at an airport with an operating control tower, the pilot receives by radio a clearance to approach or depart, as well as pertinent information about the traffic pattern. If there is not a control tower, it is the pilot’s responsibility to determine the direction of the traffic pattern, to comply with the appropriate traffic rules, and to display common courtesy toward other pilots operating in the area.
The pilot is not expected to have extensive knowledge of all traffic patterns at all airports; but if the pilot is familiar with the basic rectangular pattern, it is easy to make proper approaches and departures from most airports, regardless of whether they have control towers. At airports with operating control towers, the tower operator may instruct pilots to enter the traffic pattern at any point or to make a straight-in approach without flying the usual rectangular pattern. Many other deviations are possible if the tower operator and the pilot work together in an effort to keep traffic moving smoothly. Jets or heavy aircraft frequently fly wider and/or higher patterns than lighter aircraft and in many cases make a straight-in approach for landing.
The standard rectangular traffic pattern and terms are illustrated in Figure 10-1. The terms of an airport in the pattern after takeoff are described in Figure 10-1.
Departure leg—the flightpath which begins after takeoff and continues straight ahead along the extended runway centerline.
Crosswind leg—a flightpath at right angles to the landing runway off its takeoff end.
Downwind leg—a flightpath parallel to the landing runway in the opposite direction of landing.
Base leg—a flightpath at right angles to the landing runway off its approach end and extending from the downwind leg to the intersection of the extended runway centerline (third left hand 90° turn).
Final approach—a flightpath in the direction of landing along the extended runway centerline from the base leg to the runway.
Upwind leg—a flightpath parallel to the landing runway in the direction of landing (not shown in Figure 10-1).
The traffic pattern altitude is usually 1,000 feet above the elevation of the airport surface; however, many airports use different pattern altitudes for different types of aircraft. This information can be found in the Airport/Facility Directory (A/FD). The use of a common or known altitude at a given airport is a key factor in minimizing the risk of collisions at airports without operating control towers because aircraft can be expected to be at a certain level making it easier to see.
Compliance with the basic rectangular traffic pattern reduces the possibility of conflicts at airports without an operating control tower. It is imperative that the pilot form the habit of exercising constant vigilance in the vicinity of airports even though the air traffic appears to be light. The objective is to have both the fast and the slower weight-shift control (WSC) aircraft completing the pattern at the same interval.
The slower the aircraft is, the tighter the pattern is, as shown in Figure 10-1. The terminology is a “tight pattern” or “inside pattern” for the slower WSC aircraft in operations with faster aircraft. Using Figure 10-1 as an example, if the airplane is flying the pattern at 80 knots and the WSC aircraft is flying an inside pattern at 40 knots (that is half the distance), then the WSC aircraft and the airplane will fly around the pattern with the same interval.
The WSC pilot must determine the size of the pattern to create the same interval. This is commonplace at nontowered airports where WSC aircraft operate with faster aircraft. Both aircraft are going around the pattern at the same time with the slower WSC aircraft flying a tighter pattern and the faster airplane flying the larger pattern. In Figure 10-2, the WSC aircraft is establishing an inside airport pattern turning from crosswind to downwind.
In Figure 10-3, the aircraft shown is in the middle of the downwind leg flying an inside pattern.
When entering the traffic pattern at an airport without an operating control tower, inbound pilots are expected to listen to the other aircraft on the CTAF (Common Traffic Advisory Frequency), observe other aircraft already in the pattern, and conform to the traffic pattern in use. If other aircraft are not in the pattern, then traffic indicators on the ground and wind indicators must be checked to determine which runway and traffic pattern direction should be used. [Figure 10-4 and 10-5]
Many airports have L-shaped traffic pattern indicators displayed with a segmented circle adjacent to the runway. The short member of the L shows the direction in which traffic pattern turns should be made when using the runway parallel to the long member. These indicators should be checked while at a distance away from any pattern that might be in use, or while at a safe height above pattern altitudes. When the proper traffic pattern direction has been determined, the pilot should then proceed to a point clear of the pattern before descending to the pattern altitude.
As discussed earlier, all patterns are left hand unless indicated otherwise. Sectional aeronautical charts list a right hand pattern along with the airport information as shown in Figure 10-6. The segmented circle of Figure 10-5 and the airport shown in Figure 10-6 both clearly show the patterns for this airport.