AINsight: Circle-to-land Approach Hazards

The FAA’s Aviation Safety Information Analysis and Sharing (ASIAS) program recently published a study on circle-to-land approaches that identifies contributing factors of safety issues experienced by pilots when flying this maneuver. ASIAS analyzed data from various voluntary safety programs to offer useful insights and tips for pilots conducting circle-to-land approaches.

Pilots of business aircraft must, on occasion, fly a circling approach when they cannot land from a straight-in approach due to tailwinds, obstacles, other limitations, or the need to accommodate traffic flow for ATC. Circling approaches, according to the ASIAS study, “present an increased risk to general aviation operations because they require maneuvering at low altitude and low airspeed during the final segment of the approach and landing.”

The NTSB reports that, from 2008 to 2023, there were 10 accidents involving Part 91 or 135 operators during circling approaches, resulting in 17 fatalities.

An NTSB safety alert further cautions pilots: “Circling approaches can be riskier than other types of approaches because they often require maneuvering at low altitude and low airspeed during the final segment of the approach, increasing the opportunity for loss of control or collision with terrain. These risks are heightened when conducting circling approaches in marginal or reduced visibility conditions, and increased focus is required.”

ASIAS analysis identified three areas of interest for flight crews:

1. There is a subset of airports where conducting circling approaches is more common and conducted at a higher rate than at other airports in the National Airspace System. Pilots should be aware of the individual characteristics that require circling approaches at the airports and conduct thorough preflight and pre-approach briefings.

These airports include Teterboro (KTEB) in New Jersey; Atlanta DeKalb–Peachtree (KPDK); Chicago Executive (KPWK); Arlington Municipal (KGKY) in Texas; Eagle County Regional (KEGE) in Colorado; Scottsdale (KSDL) in Arizona; Long Beach (KLGB) and Van Nuys (KVNY) in California; and Southwest Oregon Regional (KOTH) and Rogue Valley International–Medford in Oregon (KMFR).

2. Flight crews should be aware of the circling approach obstacle protection airspace for the individual approach and airport to be used. This airspace changes both with minimum descent altitude (MDA) and aircraft category.

Flight crews should pay particular attention to differences between standard and expanded circling airspace maneuvering areas. The most recent TERPS and ICAO PAN-OPS circling criteria updates account for elevation (for example, true airspeed) and wind up to a maximum of 25 knots. Approaches with the new larger circling minima are displayed on Jeppesen approach charts with a “C” in a black square.

ASIAS recommends that pilots use all available tools to remain aware of their distance from the airfield and stay within the obstacle protection area. According to the ASIAS analysis, some flights were observed flying at low altitudes beyond the proper protected zone.

In addition, the study found that Category A and B aircraft that purposefully operate at higher Category C or D minima (larger protected areas) fly at higher altitudes and further away from obstacles, further increasing safety margins.

3. There’s a link between circling approaches and unstable approaches. With proper preflight and approach briefings, flight crews can better prepare for these types of approaches and ensure a successful, stabilized approach to landing.

ASIAS data analysis identified the following safety issues: unstable approach, low power on approach, GPWS sink rate, go-around, high-energy descent, loss of situational awareness, and high crew workload.

Guidance

Before the ASIAS study and NTSB alert on circling approaches, the FAA provided sound guidance in its “Instrument Procedures Handbook” and “Aeronautical Information Manual” (AIM).

The FAA’s handbook urges caution when attempting a circle-to-land maneuver: “Circling approaches are one of the most challenging flight maneuvers in the National Airspace System, especially for pilots of Category C and Category D turbine-powered transport category airplanes. The maneuvers are conducted at low altitude, day, and night, and often with precipitation present affecting visibility, depth perception, and the ability to adequately assess the descent profile to the landing runway.”

Furthermore, AIM 5-4-2(f) states, “Circling may require maneuvers at low altitude, a low airspeed, and in marginal weather conditions. Pilots must use sound judgment, have an in-depth knowledge of their capabilities, and fully understand the aircraft performance to determine the exact circling maneuver since weather, unique airport design, and the aircraft position, altitude, and airspeed must all be considered.”

In its safety alert, the NTSB recommends, “Before conducting a circling approach, be sure it is the best option and then brief the approach, plan its execution, and acknowledge your own limitations.”

Operators and pilots should assess whether flying a circling approach is worth its risks compared to a straight-in approach.

The NTSB safety alert provides the following excellent guidance on circling approaches:

• Fully understand the risks involved with performing a circling approach and use sound judgment if deciding to perform this approach.
• Consider your personal experience and limitations and the performance capabilities of your aircraft when planning the execution of the circling approach. Weather, runway configuration, and your aircraft’s current position, altitude, and airspeed should also be considered.
• Understand that if ATC issues you a clearance for a circling approach, you can request a different approach or divert to an airport with more capable approach facilities. It is always better to make ATC aware of your concerns rather than to attempt an approach you might not be comfortable performing.
• Acquire recurring, scenario-based training in realistic environments that includes circling approaches. Practicing these approaches routinely will increase your proficiency and make you more comfortable performing them when needed.
• If you decide to perform a circling approach, conduct a comprehensive briefing that specifies when the circling approach will begin, descent altitudes and locations, airspeeds, aircraft configuration, and go-around (or missed approach) criteria and procedures.
• When conducting a circling approach, remain at or above the circling altitude until the aircraft is continuously in a position from which a descent to landing on the intended runway can be made at a normal rate using normal maneuvers.

The ASIAS circling approach study suggests that flight crews should review the following while briefing the approach: any differences in requirements for day versus night; any notes/restrictions associated with the circling approach; whether automation can support the circle-to-land maneuver; the hazards of being low and slow, high, and fast, or unstable; the potential increase in workload and loss of situational awareness when conducting circling approaches; the impact of deteriorating weather; and the missed approach procedure and pattern from various circling positions.

Further reading: 

AINsight: Circling Can Be a Very Risky Approach

Related NTSB Aviation Investigative Final Reports:

Teterboro, New Jersey (CEN17MA183)

Truckee, California (WPR21FA286)

El Cajon, California (WPR22FA068)