Ten Delay Causes Leave the Airline Column on October 19: What the DOT's Section 511(b) Rule Changes for Meals and Hotels

The final rule amends Part 234 of Title 14 of the Code of Federal Regulations, the section that requires large US carriers to report to the Bureau of Transportation Statistics (BTS) why flights are delayed or cancelled. It was signed by Transportation Secretary Sean Duffy and published in the Federal Register on September 3, 2026, under docket DOT-OST-2026-1257. It becomes effective 45 days after publication, which law-firm and trade coverage puts at October 19.

Since 2002, carriers have reported delays of 15 minutes or more using five categories: Air Carrier, Extreme Weather, National Aviation System, Security and Late Arriving Aircraft. Cancellations use the same list without Late Arriving Aircraft. The Air Carrier category is the one reserved for circumstances within the airline's control. According to the filing, it has historically covered items such as maintenance, crew scheduling and aircraft cleaning, along with a long list in a BTS technical directive that includes baggage loading, catering, fuelling, slow boarding, medical emergencies and removal of an unruly passenger.

The new rule adds a sixth category for delays and a fifth cancellation code, "E", both labelled Section 511(b). The name comes from Section 511(b) of the FAA Reauthorization Act of 2024, which became law on May 16, 2024, and which says ten listed events "shall not be included within the Air Carrier code." The department rewrote the Air Carrier definition so that it must not include them, and created the new category so that these events are not folded into Extreme Weather, National Aviation System or another existing code.

The ten events

The rule text lists the ten events as follows:

1. Aircraft cleaning necessitated by the death of a passenger.
2. Aircraft damage caused by extreme weather, foreign object debris or sabotage.
3. A baggage or cargo loading delay caused by an outage of a bag system not controlled by a carrier or its contractor.
4. Cybersecurity attacks, provided the air carrier is in compliance with applicable cybersecurity regulations.
5. A shutdown or system failure of government systems that directly affects an airline's ability to conduct flights safely and is unexpected.
6. Overheated brakes due to a safety incident resulting in the use of emergency procedures.
7. Unscheduled maintenance, including in response to an airworthiness directive, manifesting outside a scheduled maintenance program that cannot be deferred or must be addressed before flight.
8. An emergency that required medical attention through no fault of the carrier.
9. The removal of an unruly passenger.
10. An airport closure due to the presence of volcanic ash, wind or wind shear.

The cybersecurity exclusion applies only if the airline is complying with applicable cybersecurity rules; Crowell & Moring, a law firm that published a client alert on the rule, notes that a carrier unable to show compliance risks having the event classified as Air Carrier, with the reporting and customer-service consequences that follow.

Why there was no public comment

The department issued the rule without a proposal or comment period. Under the Administrative Procedure Act, an agency may do so when it finds, for good cause, that notice and comment is unnecessary. The filing says the exclusions are not discretionary and that the final regulation uses the statutory language without further interpretation, so public comment was unnecessary.

The same reasoning is used to separate what the rule does from what it leaves for later. Section 511(a) of the 2024 law separately requires the BTS director to start a rulemaking creating a "cause of delay" category for delays caused by instructions from the FAA's air traffic control system. In addition, Airlines for America, the main US airline trade group, filed a petition in October 2024 asking the department to move faster and to make further changes to on-time reporting. The department says both items involve discretion and therefore require notice and comment. BTS plans to address them in future rulemaking.

What the department says about cost

The economic analysis in the filing is unusually direct about who gains and who loses. On benefits, it says the rule makes the data that airlines report, and that the department publishes, consistent with federal law and with Congress's judgment about what falls outside airline control. It adds that the improvement in information cannot be reliably quantified.

On costs, it says the rule produces an overall cost saving. Thirteen carriers report data for calendar year 2026. The department treats airline compliance costs as de minimis in one scenario, and in another estimates $8,659 per carrier, or $112,567 across the 13. The department says carriers will save substantially more than that because the rule reduces what it calls the negative reputational impact of having uncontrollable events counted against them in public data.

The filing then turns to passengers. All reporting carriers that sell tickets commit in their customer service plans to provide amenities at no cost for lengthy controllable delays and controllable cancellations, and some also commit to non-cash compensation. With ten causes removed from the Air Carrier category, the department wrote, the number of delays and cancellations that trigger amenities and compensation is expected to fall. It says it cannot estimate by how much because it has no visibility into how often the ten causes occur. It characterises any reduction as "a transfer of value from consumers back to air carriers," in its words, rather than a cost to consumers or a benefit to airlines.

That passage is the heart of the dispute. The rule itself changes only how events are coded in the data sent to BTS. But the airline commitments the department refers to are tied to whether a disruption was within the carrier's control, and the department expects the new coding to shrink the set of disruptions that qualify.

What does not change

The rule does not touch several protections. The Crowell & Moring alert notes that the obligations in airline customer service plans are what change in practice, because carriers committed to amenities and, in some cases, compensation for long controllable disruptions; it advises companies to review those plans and their passenger communications. Neither that alert nor the department's filing says that refund rights or rebooking duties are altered, and the rule text amends only the reporting regulation.

What to watch

Three things are not yet known. First, the department says it cannot measure how often the ten causes occur, so the size of the reduction in meals, hotels and compensation has not been estimated. Second, the material reviewed here does not show whether airlines will change their customer service commitments. Third, the follow-on rulemaking on air traffic control delays and the trade group's petition could alter the reporting framework again, this time with public comment.

From October 19, the monthly delay-cause data that BTS publishes will carry a new column. Whether travellers see it in their own experience at the gate will depend on how each airline applies its own commitments to the disruption in front of it.

Sources

• US Department of Transportation, Bureau of Transportation Statistics, final rule "Cause of Airline Delay and Cancellation Categories under Section 511(b) of the FAA Reauthorization Act of 2024" (Federal Register document 2026-18040, public inspection copy, publication date September 3, 2026)
• Crowell & Moring, client alert "DOT Final Rule Narrows Airline Delay and Cancellation Reporting Obligation Under FAA Reauthorization Act of 2024," September 3, 2026
• Upgraded Points, "New DOT Rule Means Less Compensation for Passengers," updated September 4, 2026