ATI B767-300 Incident at Chicago Rockford: Flap Damage on Approach

On May 7th, 2024, an ATI Air Transport International Boeing 767-300, registration N409AZ, operating on behalf of Amazon Prime Air, encountered difficulties during its approach to Rockford Airport (RFD) in Illinois, USA. The aircraft was performing flight 8C-3372 from Ontario International Airport (ONT) in California to Rockford, carrying cargo for Amazon Prime Air. The flight, which was expected to be routine, faced several challenges due to adverse weather conditions, ultimately resulting in damage to the aircraft’s flaps.

Sequence of Events:

Initial Approach and First Go-Around:

The flight was on final approach to Rockford’s runway 25 when air traffic control (ATC) advised the crew of heavy precipitation expected until the aircraft reached approximately 2 nautical miles (nm) from the runway. The crew continued their approach, descending through 1,600 feet Mean Sea Level (MSL). However, as the aircraft neared its final approach path, ATC issued a low altitude alert. This alert is triggered when an aircraft is detected below the safe approach path, indicating a potential risk of collision with terrain or obstacles.

In response to the low altitude alert, the flight crew initiated a go-around, which is a standard procedure to abort the landing attempt and climb back to a safe altitude. During this time, the crew reported encountering wind shear, a sudden change in wind speed and/or direction that can significantly affect the aircraft’s stability and flight path. The wind shear had caused the aircraft to become unstable, prompting the decision to execute the go-around maneuver.

Holding Pattern and Second Go-Around:

After the go-around, ATC instructed the crew to enter a holding pattern at 4,000 feet, approximately 4 nm from the airport, advising that they would exit the adverse weather conditions after about 4 nm. The holding pattern allowed the crew to assess the situation, monitor weather conditions, and prepare for another approach attempt.

After holding for about an hour, the crew received clearance from ATC for a second approach to runway 25. However, as the aircraft approached, ATC again issued a low altitude alert, which was also audible in the cockpit recording. The tower issued a second low altitude alert to the crew, who responded by initiating a second go-around due to the aircraft’s position below the safe approach path.

Third Approach and Landing:

Determined to complete the flight safely, the crew decided to make a third attempt to land on runway 25. During this final approach, the aircraft managed to stabilize on the glide path and successfully touched down on the runway. The landing was uneventful, and the aircraft taxied to the apron while maintaining routine communication with ATC. At this point, there were no indications of any immediate problems or damage to the aircraft.

Post-Flight Inspection and Damage Discovery:

After the aircraft arrived at the gate, a routine post-flight inspection was conducted by maintenance personnel. During this inspection, damage was discovered on the left forward inboard flap. Flaps are critical control surfaces located on the wings of an aircraft, which help to increase lift during takeoff and landing. Damage to these components can significantly affect an aircraft’s aerodynamic performance and safety, particularly during landing.

The damage was reported to the Federal Aviation Administration (FAA), which subsequently documented the incident stating: “AIRCRAFT LANDED AND POST FLIGHT INSPECTION REVEALED DAMAGE TO THE LEFT FORWARD INBOARD FLAP, ROCKFORD, IL.” The damage was classified as minor, but it required repairs before the aircraft could return to service. The aircraft remained on the ground at Rockford Airport for approximately 18 hours after the incident to facilitate the necessary inspections and repairs.

Analysis of the Incident:

The incident highlights several key factors that contributed to the challenging approach and subsequent flap damage:

1. Adverse Weather Conditions: Heavy precipitation and wind shear were significant contributing factors to the unstable approach. Wind shear, particularly at low altitudes during landing, poses a serious threat to flight safety as it can cause rapid changes in airspeed and direction, leading to control difficulties.
2. Go-Around Decisions: The decision by the flight crew to perform two go-arounds demonstrated their adherence to safety protocols. Go-arounds are a standard procedure in aviation when the approach is deemed unsafe, allowing the crew to reassess and attempt another landing under better conditions.
3. Low Altitude Alerts: The repeated low altitude alerts from ATC indicated that the aircraft was below the prescribed glide path on both approach attempts. This could have been caused by a combination of factors, including the wind shear and potential downdrafts associated with the adverse weather. The alerts served as a crucial safety measure, prompting the crew to take corrective action.
4. Damage Discovery: The damage to the left forward inboard flap was not immediately apparent during the flight or upon landing. It was only discovered during the post-flight inspection, highlighting the importance of thorough inspections following abnormal events such as multiple go-arounds in adverse weather.

Conclusion:

The incident involving ATI Air Transport International’s Boeing 767-300 underscores the challenges faced by flight crews when operating in adverse weather conditions, particularly during critical phases of flight such as landing. The crew’s decision-making in performing multiple go-arounds and communicating effectively with ATC contributed to the safe outcome of the flight. The discovery of flap damage during the post-flight inspection serves as a reminder of the potential impact of such conditions on an aircraft’s structural components.

While the damage was classified as minor and the aircraft remained on the ground for less than a day, the incident will likely prompt a review of the crew’s actions, the aircraft’s performance, and the weather conditions to identify any lessons that could enhance safety in future operations. The FAA’s involvement and documentation of the event will contribute to ongoing efforts to improve safety protocols and training for handling such situations.