Boeing 737 safety advisory: No flight disruptions, but Indian airlines may face plane delivery issues

Boeing 737 rudder control systems issue

Safety related issues surrounding the Boeing 737 aircraft have resurfaced once again after the US National Transportation Safety Board (NTSB) in its Aviation Investigation Report highlighted concerns over the aircraft equipped with a certain type of rudder control system.

Following the NTSB's safety alert last week, the Indian aviation watchdog, the Directorate General of Civil Aviation (DGCA) on October 7 asked Indian domestic airlines operating Boeing 737 aircraft with actuators manufactured by Collins Aerospace to not use the planes for low-visibility landings due to a “possible risk of jamming” after a loss of control incident involving a United Airlines flight in New Jersey in February 2024.

Last month, the NTSB had said more than 40 foreign operators of Boeing 737 airplanes may be using 737 or 737 Next Generation planes with rudder components that could pose safety risks.

The DGCA among other measures, has asked airlines to mandatorily include safety risk assessment of the aircraft. The DGCA’s advisory is specifically for the Collins Aerospace SVO-730 rudder actuator.

"All flight crews are to be informed through a circular/advisory regarding the possibility of a jammed or restricted Rudder control system. Appropriate mitigations must be communicated to help crews identify and handle such a situation," the DGCA said in a statement on Monday adding that "all operators must conduct a Safety Risk Assessment for aircraft to evaluate and mitigate the risk associated with the Rudder control system."

How will the new rudder issue impact domestic flights in India?

Among the Indian airlines, Air India Express, SpiceJet and Akasa have the Boeing 737 planes in their fleet. The three airlines have around a 100 737 aircraft in their fleet, with Air India Express operating 61, Akasa 25 and SpiceJet 11 at the moment.

While Air India Express said five of its 88-aircraft strong fleet had the specific rudder part, SpiceJet said there were no planes in its fleet with the snag-prone component. Akasa Air did not reply to a query mailed to it.

Aviation insiders and industry experts suggest that while the issue is not likely to have a massive impact on the domestic schedules of Indian airlines, it may affect the ability of Indian airlines to increase the strength of their fleet in the next few years.

"The rudder jamming issue of the new Boeing planes is not directly expected to impact the fleet of Indian airlines but can have a cascading impact on Boeing's ability to deliver new planes," Lokesh Sharma, a senior aviation analyst, told Moneycontrol. He added that if Boeing is forced to recall planes to address the rudder control systems issue it may impact the original equipment manufacturer’s (OEM) ability to meet its delivery schedule.

Will the employee strike at Boeing disrupt the delivery schedule?

Industry experts also pointed out that the ongoing strike of a Boeing employees union representing around 33,000 workers will impact the OEM’s ability to deliver on its 5,000 outstanding orders.

The strike over wage revision, which has now lasted for more than a month without a resolution in sight, has brought the production of Boeing’s best-selling 737 narrow-body aircraft to a grinding halt.

"Air India Express was expected to take delivery of nearly 60 Boeing 737 planes over the next 12 months and Akasa Air is expected to take delivery of another 30 planes in the same period, the ongoing strike at Boeing coupled with the new safety issues is likely to seriously hinder the OEM's ability to deliver planes on time," a senior official from a domestic airline said.

He added that airlines operating Boeing planes in India will also find it hard to lease out planes from the secondary market following the rudder control systems issue as DGCA may not allow the import of such aircraft.

What is the rudder control systems issue?

The rudder control systems issue stems from the NTSB's investigation into a United Airlines Boeing 737 Max 8 that experienced 'stuck' rudder pedals while landing at Newark Liberty International Airport in February.

After the incident, the NTSB tested a rudder control component known as the rollout guidance actuator from the aircraft and found that the functionality of the part, produced by Collins Aerospace, was significantly compromised. The company determined that a sealed bearing was improperly assembled during production, leaving it susceptible to moisture, which can freeze and impede the rudder system’s movements.

The safety board said it had been notified that more than 350 defective parts were delivered to Boeing, but it was not immediately clear how many planes with the affected component might be in service.

Following the NTSB's investigation it urged the US Federal Aviation Administration (FAA) to determine whether the faulty parts should be removed from service and, if so, to mandate that airlines replace them.

It also recommended informing international aviation regulators to encourage similar actions. The FAA said in a statement that it had “been monitoring this situation closely” and would convene a panel to determine its next steps. Last week the FAA issued a safety alert to airlines warning of the potential for limited or jammed rudder movement on certain Boeing 737 airplanes.

Boeing said it was reviewing the safety board’s recommendations and working “to develop additional guidance to address the potential condition”.

What measures has the DGCA instructed Indian airlines to implement regarding the rudder control systems issue?

The DGCA has asked airlines operating Boeing 737 aircraft with a specific rudder part to not use the planes for low-visibility landings due to a possible risk of jamming.

"We have asked Indian operators to notify their crew that rudder control system might get jammed inflight or during landing due to moisture that could accumulate and freeze in the actuator. Further, crew has been advised to refer to the flight manual called Quick Reference Handbook," the DGCA official said.

"These interim measures aim to enhance safety and ensure that flight crews are well-prepared to handle potential Rudder control issues effectively, pending further detailed operational guidance to be issued by Boeing/FAA," the DGCA notification said.

Until further notice, such aircraft will not be undertaking 'Category III B' landing or operations, said DGCA. A category III B approach is a precision landing with a decision height lower than 50 feet and a runway visibility between 700 and 150 feet.

Airlines have been instructed to include training exercises that simulate scenarios involving a jammed or restricted rudder control system. The DGCA has also asked airlines to include specific exercises in Recurrent Training and Instrument Rating/Proficiency Check (IR/PPC) that simulate scenarios involving a jammed or restricted rudder control system, including rollout procedures.

During pre-simulator briefings for recurrent training as well as proficiency checks, discussions over the rudder control system need to be included as a mandatory topic, the DGCA said.