Pilot Deviations and Runway Incursions

Overview

A pilot deviation is the result of a pilot action that violates a Federal Aviation Regulation. The majority of pilot deviations (69%) occur during GA operations.

Types of Deviations

Pilot deviations are classified as either airborne deviations (77%) or surface deviations (23%).

Airborne Deviations

Airborne deviations can result when a pilot strays from an assigned heading or altitude, instrument procedure, or if they penetrate controlled or restricted airspace without ATC clearance.

Types of IFR deviations (listed in order of occurrences):

  • Altitude violations (e.g., failure to maintain the assigned altitude)
  • Course clearance violations
  • Airspeed violations
  • Missing a compulsory reporting point

Types of VFR deviations (listed in order of occurrences):

  • Airspace violations (e.g., flying into prohibited airspace without clearance)
  • Flying VFR into IMC
  • Low-level flight
  • Required aircraft equipment is not installed or operating

Surface Deviations

Surface deviations include taxiing, taking off, or landing without clearance, deviating from an assigned taxi route, or failing to hold short of an assigned clearance limit. Vehicle and pedestrian deviations on an airport movement area can also occur.

The primary area of concern within the surface deviation classification involves runway incursions.

Runway Incursions

The FAA formally defines a runway incursion as "any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle, or person on the protected area of a surface designated for the landing and takeoff of aircraft."

A surface incident is similar to a runway incursion but occurs on a designated movement area (not a runway) and affects or could affect the safety of flight.

Types of Runway Incursions

Pilot Deviations: Crossing a runway hold marking without a clearance or taking off or landing without a clearance.

Operational Incidents: Clearing an aircraft onto a runway while another aircraft is landing on the same runway.

Vehicle Deviations: Crossing a runway hold marking without ATC clearance.

Runway Incursion Severity

DCBAAccident
DCBAAccident
Incident that meets the definition of runway incursion but with no immediate safety consequences.An incident characterized by ample time and/or distance to avoid a collision.An incident in which separation decreases, and there is a significant potential for collision, which may result in a time-critical evasive response to avoid a collision.A serious incident in which a collision was narrowly avoided.An incursion that resulted in a collision.

Runway Incursion Statistics

In the U.S., an average of three runway incursions occur daily. According to FAA data, approximately 65% of all runway incursions are caused by pilots, of which GA pilots cause 75%.

Investigations of runway incursions have identified four major contributing factors:

  • Failure to comply with ATC instructions
  • Lack of airport familiarity
  • Nonconformance with standard operating procedures
  • Distractions during taxi operations

Wrong Runway Departures

Wrong Runway Departure

Wrong runway departures are a subset of runway incursions. No one intends to take off on the wrong runway, but it still happens.

Major contributing factors to wrong runway departures:

  • Short taxi distance (less time to spot errors)
  • Single runway airports
  • A single taxiway leading to multiple runway thresholds
  • The close proximity of multiple runway thresholds

Best practices for preventing wrong runway departures:

  • Trace the taxi route to the departure runway on the airport diagram.
  • If uncertain about the taxi route, request progressive taxi instructions.
  • Verify each airport marking and sign along the taxi route.
  • Avoid distractions while the aircraft is moving ("heads up, eyes out").
  • Set the heading bug before taxiing. Before adding power, ensure that the aircraft heading is aligned with the heading bug and runway heading.

Wrong Direction Departures from an Intersection

Wrong Direction Intersection Departure

A wrong direction departure occurs when a pilot is cleared for an intersection takeoff and then departs in the wrong direction.

Major contributing factors to wrong direction departures:

  • Feeling rushed into the situation
  • Misinterpreting airport markings and signs
  • Not being fully prepared and ready when reaching the hold short line

Additional best practices for preventing wrong direction departures:

  • At a towered airport, do not confuse an instruction to turn after departure with a turn onto the runway.
  • Visualize the runway holding position sign as the runway (e.g., the runway number on the left side of the sign is to the pilot's left).

Wrong Surface Landings

A wrong surface landing occurs when an aircraft lands or tries to land on the wrong runway, on a taxiway in error, or at the wrong airport.

Pilots can avoid such incidents by:

  • Identifying any nearby airports with similar runway alignments that may result in confusion.
  • Studying the airport diagram and lighting ahead of time and noting key features and geometry.
  • Backing up all visual approaches with instrument guidance. [IFR]
  • Referring to moving map displays to increase situational awareness and safety.
  • Taking a moment on every final approach to verify the correctness of the runway alignment and runway number.

Types of Errors that Can Lead to Deviations

Inadvertent pilot deviations can result from a variety of error types, including decision errors, skill-based errors, and perceptual errors.

Decision Errors (Cognitive)

Decision errors are "honest mistakes" that occur when one does not have the appropriate knowledge or makes a poor choice. An action is carried out as intended but is inadequate for the situation.

Skill-Based Errors (Motor Control)

Skill-based errors are "stick-and-rudder" mistakes that occur without significant conscious thought. A person intends to carry out an action but carries it out incorrectly, and the desired goal is not achieved.

Perceptual Errors (Sensory)

Perceptual errors are due to incorrect responses to illusions. These can occur when sensory input is degraded at night or in other situations causing reduced visual acuity.

Best Practices for Avoiding Airborne Deviations

Plan Each Flight: Always review NOTAMs, even when flying to a familiar airport. Conditions can change rapidly, like a pop-up temporary flight restriction (TFR).

Talk and Squawk: ATC can act as another set of eyes and has the latest local TFR information.

Give Yourself Some Room: Using a GPS to fly along an airspace boundary could result in a pilot deviation if ATC radar shows the aircraft within the restricted airspace. It is best to use at least a 5 NM buffer.

Stay Alert: Avoid distractions by maintaining a sterile cockpit when appropriate.

Best Practices for Avoiding Surface Deviations

The best way to avoid a runway incursion is to make sure you understand (1) where you are at, (2) what you have been cleared to do, and (3) where you are going.

Standard Operating Procedures (SOPs): GA pilots should develop and adhere to SOPs based on regulations and industry best practices. A sterile cockpit and proper use of aircraft lights should be defined in every pilot's set procedures.

Situational Awareness (SA): To establish SA, pilots should review the expected taxi route and location of hot spots. To maintain SA, pilots should avoid heads-down time when taxiing.

Proficiency: Recurrent training and continuing education lead to proficiency. A flight to a towered airport with an experienced instructor is a good way to learn and practice.

Point and Acknowledge: Pointing at and calling out location signs and markings can help a pilot maintain focus and attention.

Pilot Notification of Suspected Deviations

When it appears that a pilot's actions constitute a possible pilot deviation, ATC notifies the pilot as soon as operationally practicable.

"[call sign] possible pilot deviation, advise you contact Huntsville Tower at [telephone number]."