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The FAA proposes inspecting elevator-control bearings on an estimated 95 U.S.-registered 737-8, 737-9 and 737-8200 airplanes after a report that the bearings may have been installed incorrectly in production, including without sealant, and the Boeing bulletin it would make mandatory gives operators 126 months to look.

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A proposed airworthiness directive published September 21 (Docket No. FAA-2026-8811) would require detailed inspections of the elevator buss assembly bearings and bearing housings on certain Boeing 737-8, 737-9 and 737-8200 airplanes; an FAA directive from 2020 calls the first two the 737 MAX. The FAA says it received a report that the bearings 'could have been installed incorrectly (including being installed without the application of sealant) during production', which could lead to cracking in the bearings and housings and premature failure of the assembly's crank arms and could impact elevator pitch control. It estimates 95 U.S.-registered airplanes are affected, at $1,955 per airplane for the inspection and $185,725 for U.S. operators; replacing a whole assembly would cost an estimated $98,496. The deadline is not in the proposal. It sits in the Boeing bulletin posted in the docket: 126 months, which for airplanes already flying would count from the final rule's effective date, with no repeat inspection. Under the bulletin, a crack or missing sealant must be fixed before further flight. The 737 MAX-7, certified August 3, is not among the airplanes listed. Comments are due November 5, 2026.

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On September 21 the Federal Aviation Administration published a proposed airworthiness directive for three versions of Boeing's 737: the 737-8, the 737-9 and the 737-8200. An FAA directive from November 2020, AD 2020-24-02, refers to the 737-8 and 737-9 as the 737 MAX. Here is what prompted the new proposal, in the agency's words:

The FAA has received a report indicating that bearings in the elevator buss assembly could have been installed incorrectly (including being installed without the application of sealant) during production.

The proposal then explains why that matters:

The elevator buss assembly is part of the elevator controls system and assists in the movement of the control columns. Improper installation of bearings could lead to cracking in the elevator buss assembly bearings and bearing housings, which could lead to premature failure of the elevator buss assembly crank arms. This condition, if not addressed, could impact elevator pitch control and affect continued safe flight and landing of the airplane.

The deadline is in the docket

The proposal gives no inspection deadline itself. It would require the actions in Boeing Alert Requirements Bulletin 737-27A1331 RB, dated December 17, 2025, and refers readers to the docket "For information on the procedures and compliance times".

The bulletin, which this desk read there, calls for one detailed inspection of the bearings and housings, then a push-out load test if no crack is found and sealant is present. Both are due at whichever is later: 126 months after the bulletin's issue date, or 126 months after the airplane's original standard or export certificate of airworthiness. No repeat is set. Where the bulletin counts from its own issue date, the proposed rule says "this AD requires using the effective date of this AD".

So an airplane already flying when a final rule takes effect would have 126 months, ten and a half years, from that date to be inspected. For a crack, missing sealant or a failed load test, the bulletin's time for the fix is "Before further flight."

The numbers

  • 95 airplanes of U.S. registry, by the FAA's estimate. By this desk's count the bulletin lists 222 airplanes by line number in all.
  • Inspection: 23 work-hours at $85 an hour, $1,955 per airplane and $185,725 for U.S. operators.
  • Replacements, if needed: $1,105 to $1,809 per bearing, or $98,496 to replace the whole elevator buss assembly. The FAA "has no way of determining the number of aircraft that might need these replacements".
  • Warranty: "According to the manufacturer, however, some or all of the costs of this proposed AD may be covered under warranty".

Not on the list: the MAX-7

On August 3 the FAA certified the 737 MAX-7 and said the updated Production Limitation Record "authorizes Boeing to begin production of the aircraft." It said FAA safety inspectors "will remain on site at Boeing production facilities across the country to closely monitor the manufacturing process". The bearing proposal and the bulletin's list of affected airplanes name only the 737-8, 737-9 and 737-8200. Neither says whether the MAX-7 uses the same assembly.

How to comment, by November 5, 2026

Comment online through docket FAA-2026-8811 on regulations.gov, by fax to 202-493-2251, or by mail to U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. Begin with "Docket No. FAA-2026-8811; Project Identifier AD-2025-01891-T". The FAA says the most helpful comments "reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data." It will post comments "without change, to regulations.gov, including any personal information you provide." The docket showed four public comments on September 27.

What the record does not say

  • Who made the report, or when. No source or date is given.
  • Whether anything has failed. No cracked bearing or failed crank arm in service is cited.
  • When the airplanes were built. The bulletin lists them by line and variable number only.
  • What some repairs cost. The FAA says it has no definitive data for some of them.
  • Whether the MAX-7 is affected.
  • Fault. This is a proposed safety rule, not an enforcement action, and the FAA "may amend this proposal because of those comments."

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