Introduction to the Boeing 737 Rudder Actuator Issue
In a detailed letter addressed to the Federal Aviation Administration (FAA), Jennifer Homendy, the chair of the National Transport Safety Board (NTSB), raised significant safety concerns regarding certain Boeing 737 models. These aircraft are potentially equipped with defective rudder actuators manufactured by Collins Aerospace. This safety issue first came to light following an incident involving a United Airlines 737 MAX 8 at Newark Liberty International Airport (EWR) in February 2024. The incident, involving jammed rudder pedals during landing, prompted an in-depth investigation by the NTSB.
Extent of the Issue
The investigation revealed that the problematic actuators are the Collins Aerospace SVO-730 rudder rollout guidance actuators. Testing by the manufacturer confirmed that these actuators were defective, leading to potential safety risks during flight operations. According to the NTSB, a total of 353 affected actuator units were delivered to Boeing from February 2017 onwards. Notably, 73 of these units were not installed on any aircraft. However, the remaining 280 units were distributed among at least 40 foreign air carriers and some U.S. airlines, including United Airlines.
Boeing had already taken steps to address the issue by removing the affected actuators from all 25 U.S.-registered aircraft identified, including nine operated by United Airlines. The remaining units, however, pose a risk to numerous international flights.
Response from Boeing and FAA
Following the discovery, Boeing issued a Multi Operator Message on August 23, 2024, informing both domestic and international operators about the defective part. Boeing has reassured that the 737 models can be safely operated without the rudder rollout guidance actuator installed. However, the NTSB has expressed concerns about Boeing’s suggested mitigation strategies, which involve managing a potential jam in the rudder control system during landing. The fear is that these measures could lead to sudden, unintended rudder movements, possibly resulting in a loss of control or runway departure.
The FAA’s response to the initial reports was deemed insufficient by the NTSB, prompting further criticism from Homendy. The FAA had not taken significant action until the NTSB issued an urgent safety recommendation in September 2024, despite prior incidents and ongoing risks highlighted by the NTSB’s preliminary report six months earlier.
Criticisms and Recommendations
Homendy’s critique extends beyond the FAA’s delayed response. She has also pointed out that Boeing failed to adequately inform United Airlines about the connection of the actuators to the rudder control system in the planes delivered to them. This lack of communication could potentially endanger flight safety, as operators might not be aware of the installed systems and how to handle failures.
The NTSB has recommended the immediate removal of all affected Collins Aerospace SVO-730 rudder rollout guidance actuators from service to eliminate the risk of rudder control restrictions. They have also called for more stringent oversight and quicker response measures from both Boeing and the FAA to address such critical safety issues promptly.
Conclusion
The ongoing situation with the Boeing 737 rudder actuators is a stark reminder of the complexities and critical nature of aerospace component integrity. As investigations continue and new measures are implemented, both Boeing and the FAA are under scrutiny to enhance their response strategies and ensure the highest safety standards are upheld to protect passengers and crew alike.