DGCA issues advisory to airlines operating Boeing 737s over 'potential risk' in rudder control

DGCA issues advisory to airlines over Boeing 737 planes equipped with Collins Aerospace SVO-730 rudder guidance system

The civil aviation regulator has issued an advisory to all airlines operating Boeing 737 aircraft, instructing them to address concerned raised in a US investigation report over the 'potential risk' of a malfunction of the rudder control system.

The Directorate General of Civil Aviation (DGCA)'s safety recommendations come in light of a US National Transportation Safety Board (NTSB) Aviation Investigation Report that highlighted safety concerns in Boeing 737 aircraft equipped with a certain type of rudder control system.

The decision by the DGCA is an interim measure, a DGCA official said, adding that the aviation watchdog will work with Boeing before coming out with a long term strategy to address the issue.

"We has 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.

Boeing in a statement said they are working with the supplier to develop additional guidance for the potential condition.

"In August, we informed affected 737 operators of a potential condition with the rudder rollout guidance actuator, which is part of an optional autoland system. The autoland system includes layers of redundancy and we are working with our supplier to develop additional guidance to address the potential condition. We will keep our regulator informed of our progress. We will also ensure flight crews have the appropriate operating procedures,” said Boeing.

Among the Indian airlines, Air India Express, SpiceJet and Akasa have the Boeing 737 planes in their fleet. However, the problem pertains specifically to actuators manufactured by Collins Aerospace.

"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.

The statement by DGCA cited the US aviation report on 'Collins Aerospace SVO-730 Rudder Rollout Guidance Actuators' that showed a 'potential risk' of jamming, and asked airlines to convey measures to help crews handle such a situation.

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 50ft and a runway visibility between  700 and 150 feet.

Airlines have been instructed airlines 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 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, said DGCA.

On September 30, the US NTSB  said more than 40 foreign operators of Boeing 737 airplanes, including the 737 MAXs, maybe using planes with rudder components that could pose safety risks.

Last month, the NTSB issued an urgent safety recommendations about the possibility of jammed rudder control on some 737 aircraft following an inquiry into a February incident involving a United Airlines flight. It warned Boeing and the Federal Aviation Administration (FAA), that the instructions contained in the QRH manual, which require pilots to exert maximum force on the rudder pedal in case of a jammed system, including a combined effort of both pilots, may lead to loss of control or departure from a runway because of a large input to the rudder pedals.