Aviation regulator DGCA on Monday issued an advisory to Indian airlines operating Boeing 737 aircraft regarding the potential risk of jamming of the rudder control system. The move follows a recent investigative report by the US National Transportation Safety Board (NTSB) that highlighted safety concerns associated with Boeing 737 aircraft equipped with Collins Aerospace SVO-730 rudder rollout guidance actuators.
In the backdrop of the potential risk of jamming or restricted rudder control systems, the Directorate General of Civil Aviation (DGCA) has issued safety recommendations to Indian airlines. Currently, Air India Express, Akasa Air and SpiceJet operate Boeing 737 aircraft. In total, they have about 100 such aircraft. Air India Express operates 61 Boeing 737s, while Akasa Air has a fleet of 25 Boeing 737 Max aircraft.
According to data available on Planespotters.net, SpiceJet has 11 Boeing 737 aircraft in service. In August, Boeing notified affected operators of 737 aircraft about a possible failure of the rudder rollout guidance actuator. The rudder rollout guidance actuator helps align the aircraft’s rudder with its nose wheel during takeoff and landing. This ensures proper alignment and control during critical phases of flight.
An Air India Express spokesperson said, “The advisory regarding the Boeing 737 rudder system is applicable to only five aircraft in our fleet. We have initiated the process of compliance in compliance with the regulatory requirements.” A SpiceJet spokesperson said none of its Boeing 737 NG aircraft are affected. DGCA said all flight crew should be informed through a circular/advisory about the possibility of jammed or restricted rudder control system.
“The crew should be informed of appropriate measures to help them identify and handle such a situation,” it says. Additionally, all operators have been asked to conduct a safety risk assessment for aircraft to evaluate and mitigate the risk associated with the rudder control system.
The regulator also said all Category III B approach, landing and rollout operations, including practice or actual autoland, should be discontinued for these aircraft until further notice. Category III B relates to operation in reduced visibility conditions. Among other measures, airlines have been asked to include discussion about potential rudder control system issues as a mandatory topic in recurring training sessions. This will also be covered in the Instrument Rating/Proficiency Check (IR/PPC) during the pre-simulator briefing.
“Operators have been instructed to include recurring training and specific exercises in IR/PPC that simulate scenarios involving a jammed or restricted rudder control system, including rollout procedures. During these exercises, the regulator said in a release. Appropriate flight crew responses and mitigation should be practiced.”
The DGCA also said the interim measures are aimed at enhancing safety and ensuring that flight crews are well prepared to handle potential rudder control issues effectively. The rudder rollout guidance actuator is designed to control rudder movement during Category IIIB approach, landing and rollout operations.
On September 27, Boeing said in a statement that in August, it had informed affected 737 operators about a possible situation with the rudder rollout guidance actuator, which is part of an option autoland system. It said, “The Autoland system includes layers of redundancy and we are working with our supplier to develop additional guidance to address the potential situation.”