7.pattern-altitude-and-spacing. Pattern Altitude and Spacing
The traffic pattern is a standardized rectangular flight path flown around an airport at a published altitude, designed to provide an orderly flow of arriving and departing aircraft. Two of the most important elements that keep this flow safe and predictable are pattern altitude and aircraft spacing.
Pattern Altitude
Unless otherwise specified, the standard traffic pattern altitude (TPA) for propeller-driven airplanes is 1,000 feet above ground level (AGL). Large or turbine-powered airplanes typically fly the pattern at 1,500 feet AGL. Some airports publish nonstandard pattern altitudes — for example, 800 feet AGL for noise abatement or 1,200 feet AGL where terrain dictates. The published TPA can be found in the Chart Supplement (formerly A/FD), on sectional charts, and in NOTAMs.
Key altitude practices:
- Enter the pattern at TPA on the 45° entry to the downwind leg.
- Maintain TPA throughout upwind, crosswind, and downwind.
- Begin descent abeam the intended point of landing on downwind, or after the base turn, depending on aircraft and technique.
- Climb to TPA before turning crosswind on departure (do not turn crosswind below 300 feet AGL, and not until beyond the departure end of the runway).
Pattern altitude is referenced to field elevation, not MSL. To compute the indicated altitude to fly, add field elevation to the published AGL value. For a field elevation of 1,250 feet MSL with a 1,000-foot AGL TPA, fly 2,250 feet MSL on the altimeter.
Altitude tolerance in the pattern should be tight — within ±100 feet is the practical standard, and on a checkride the ACS commonly requires altitude within ±100 feet on the downwind leg.
Spacing
Proper spacing keeps the airplane close enough to glide to the runway in the event of an engine failure, while leaving room to maneuver and to follow traffic. Standard guidance:
- Lateral spacing on downwind: approximately ½ to 1 mile from the runway. A common visual reference is to place the runway about halfway between the wingtip and the wing root (low-wing) or just outboard of the strut (high-wing) when straight and level.
- Longitudinal spacing behind traffic: maintain enough distance that the preceding aircraft will be clear of the runway before you cross the threshold. If a conflict develops, extend downwind, perform S-turns on final, or execute a 360° turn (only if cleared by tower or coordinated on CTAF).
- Wake turbulence spacing: when following a larger or heavier airplane, plan to land beyond its touchdown point and stay at or above its flightpath. Standard ATC wake separation behind a Heavy is 4–6 NM on final.
The Four Legs and Spacing Cues
- Upwind/Departure leg: climb straight ahead to within 300 feet of TPA before turning crosswind.
- Crosswind: a 90° turn from upwind; continue climbing to TPA.
- Downwind: parallel to the landing runway at TPA, opposite direction of landing. Abeam the touchdown point, reduce power, extend the first notch of flaps, and begin a stabilized descent.
- Base: a 90° turn from downwind, descending. Begin the base turn when the touchdown point is approximately 45° behind the wing.
- Final: roll out aligned with the runway centerline, ideally at least ¼ mile from the threshold, on a stable approach.
Adjusting for Traffic
When following slower aircraft, do not crowd: extend the downwind, widen the pattern slightly, or reduce airspeed early. When followed by faster traffic, keep a normal pattern; do not cut corners or descend below TPA prematurely. Avoid descending on downwind — this is a common cause of midair conflict with traffic entering on the 45.
Nonstandard Patterns and Right Traffic
Standard pattern turns are to the left. Right traffic is indicated by:
- A segmented circle with traffic indicators at the airport.
- The notation "RP" followed by runway numbers in the Chart Supplement.
- Sectional chart symbology and tower instruction at controlled fields.
Always verify the direction of turns and the published TPA before arrival. At nontowered airports, broadcast position and intentions on the CTAF on each leg, and use the published pattern altitude — straight-in approaches, while not prohibited, can conflict with aircraft in the pattern and should be coordinated carefully.
Common Errors
- Flying the downwind too close, resulting in a cramped base and final.
- Flying the downwind too wide, making engine-out glide to the runway impossible.
- Drifting above or below TPA — particularly descending early on downwind.
- Failing to compensate for wind drift, producing a non-rectangular ground track.
- Turning base too early when following faster traffic, or too late when followed by slower traffic.