FAA issues urgent Airworthiness Directive for all Boeing 747s
The measure comes in response to the discovery of external elevators installed on an aircraft without the necessary counterweights to ensure safe operation.
The U.S. Federal Aviation Administration (FAA) has issued an immediate directive affecting all Boeing 747 models following the discovery of improperly installed external elevators lacking required counterweights. The directive, designated AD 2025-09-08, took effect on May 5, 2025.
The issue came to light after a report revealed that a Boeing 747-8F was operating with a right external elevator (part number P/N 654U6625-2412) that had been received and installed without the necessary counterweights. It was later determined that both this part and its left-side counterpart (P/N 654U6625-2411) had been incorrectly delivered without counterweights, despite documentation indicating they were interchangeable with older parts (P/N 183U3300-13 and P/N 183U3300-14) that included them. Boeing has delivered ten of these replacement sets (five per side) to operators since 2022.
The absence of these counterweights presents an unsafe condition. The FAA warns that flying with such parts may cause abnormal vibrations, buffeting, flutter, or oscillations, potentially leading to loss of aircraft control, jeopardizing the safety of flight and landing. Additionally, the agency noted that the imbalance poses a risk of injury to maintenance personnel during installation or removal.
To address the issue, the directive requires all Boeing 747 operators to comply with the actions marked as “RC” (Required for Compliance) in Boeing Alert Service Bulletin 747-BSA-55-001, dated April 24, 2025. Operators must either review maintenance records to check for the affected part numbers or perform a general visual inspection of the external elevators to confirm the physical presence of counterweights. If counterweights are found to be missing, operators must follow corrective procedures, which may include properly balancing the part before flight.
Although Boeing’s original bulletin targeted the 747-400, -400D, -400F, -8, and -8F series, the FAA has extended the directive’s applicability to all variants of the Boeing 747, including models 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, 747SR, and 747SP. The agency justified this decision by noting that elevators are rotable components—they can be removed and reinstalled on different aircraft throughout their service life, meaning any 747 could potentially receive one of the affected parts.
The FAA implemented this directive as a final rule with immediate effect, bypassing the usual public comment period. It cited “good cause”, stating that the risk posed by this unsafe condition requires urgent correction to protect public safety.
The directive affects an estimated 170 aircraft registered in the United States. The cost for record verification or initial inspection is estimated at up to $340 per aircraft. The FAA did not specify the potential costs of corrective actions resulting from these checks. Operators have until June 20, 2025, to submit comments on the final rule.
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