The National Transportation Safety Board on 26 September issued "urgent safety recommendations" to Boeing and the Federal Aviation Administration "in response to the potential for a jammed or restricted rudder control system on some 737 airplanes". The NTSB says it is investigating a 6 February 2024 incident in which the rudder pedals on a United Airlines 737 Max 8 were "stuck" in their neutral position during the landing rollout at Newark Liberty International airport. "The captain used the nosewheel steering tiller to control the airplane's direction after touching down. There was no damage to the airplane or injuries to the 155 passengers and six crew members. A preliminary report detailing the circumstances of the event was published on March 12," the NTSB says. It adds that NTSB investigators tested one of the rudder control components from the incident airplane, a rollout guidance actuator, at the component's manufacturer, Collins Aerospace. When the incident actuator and an identical unit from another airplane were tested in a cold environment, the actuators' function was "significantly compromised". Investigators, the NTSB says, found evidence of moisture in both actuators, which failed testing. Collins Aerospace subsequently determined that a sealed bearing was incorrectly assembled during production of the actuators, leaving the unsealed side more susceptible to moisture that can freeze and limit rudder system movement, the NTSB adds. It says that Collins notified Boeing that more than 353 actuators that Collins had delivered to Boeing since February 2017 were affected by this condition. The NTSB explains that the rudder rollout guidance actuator, which is installed in the tail of some 737NG and Max jets, is designed to control the rudder's movement during category IIIB approach, landing and rollout operations. Although it is not used in non-precision landings, the actuator remains mechanically engaged with the rudder system, it says. According to the NTSB, Boeing's 737 flight manual instructs pilots confronted with a jammed or restricted rudder to "overpower the jammed or restricted system [using] maximum force, including a combined effort of both pilots". The NTSB expressed concern that this amount of force applied during landing or rollout could "result in a large input to the rudder pedals and a sudden, large, and undesired rudder deflection that could unintentionally cause loss of control or departure from a runway". The NTSB says it has recommended that Boeing "determine appropriate flight crew responses besides applying maximum pedal force" for such situations in flight or during landing. The NTSB also recommended that Boeing notify flight crews operating 737s with affected actuators that the rudder control system can jam due to moisture that has accumulated inside the actuators and frozen. Additionally, the NTSB recommended that the FAA determine if actuators with incorrectly assembled bearings should be removed from airplanes, and if so, to direct US operators to do so until replacements are available. The NTSB also recommended that, if the FAA determines the affected actuators should be removed, it should notify aviation regulators in other countries that oversee operators of 737 aircraft and encourage them to require removal of the affected actuators until replacements are available. Boeing says: "We thank the NTSB for their ongoing investigation and are reviewing their recommendations. 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." The NTSB notes that the investigation is ongoing and additional updates may be issued "as circumstances warrant".

Thai Airways International has repaid about Bt7 billion ($217 million) of outstanding principal and interest to its creditors as of 31 July, in line with its business rehabilitation plan. The carrier described the progress as "a great indication for proving its ability to repay debt as determined in the plan" in a 26 September filing to the Stock Exchange of Thailand. Up to 31 July, Thai has sold 12 unused aircraft for about $40 million. It has received full payment of $621,000 for one aircraft, which has been delivered to the buyer, and received a 20% deposit amounting to $122,600 for one aircraft while it is waiting to receive deposits for the remaining 10 aircraft. It also sold two unused engines for $930,000 and received a deposit of $186,000 for the transaction.

The US Department of Transportation has fined Air Canada $250,000 for operating flights carrying United Airlines' code in the Baghdad flight information region, contravening a Federal Aviation Administration flight prohibition for US operators. According to a 26 September regulatory filing, an investigation by the DOT's Office of Aviation Consumer Protection revealed that between October 2022 and January 2023, Air Canada operated "numerous flights" carrying the UA code between the United Arab Emirates and Canada that transited the FIR. "Several flights took place after OACP issued an investigation letter to Air Canada regarding this issue," the filing adds. In a response from Air Canada included in the filing, the carrier states that "it has always been aware of, and has always complied with, DOT's policy on flights over conflict zones". It says it took "immediate action" after receiving DOT notice that its codeshare flights "might have traversed" the prohibited airspace. It issued a crew alert and revised route briefing notes reminding its flight crews of the restrictions. Air Canada further states that the flights that entered the prohibited airspace were "unplanned, inadvertent, limited in number, and of brief duration" and occurred when it deployed 777-300ERs on the route, as "aircraft loads and variations from forecast weather conditions sometimes resulted in the aircraft being heavier than planned when it reached [the restricted airspace]". Air traffic control, it adds, may also have not given permission to climb to the height to avoid the restricted airspace until after the flight was already inside it. United's code was removed from Air Canda's Dubai-Toronto services on 13 January 2023. Air Canada must pay $125,000 within 60 days of 27 September and an additional $125,000 if, within one year, it violates the order's cease and desist or payment provisions. The DOT says the fine "establishes a strong deterrent against future similar unlawful practices by Air Canada and other carriers". In June, the DOT fined Emirates $1.5 million for similar airspace violations on flights that carried JetBlue Airways' code.