# Establishment of United States Area Navigation Route T-581 in the Vicinity of Missoula, Montana

**Action Urgency Score:** 30/100

| Field | Value |
|---|---|
| Agency | Transportation Department; Federal Aviation Administration |
| Type | Final rule |
| Action | Final rule; correction. |
| Published | 2026-09-18 |
| Effective | 2026-10-29 |
| Significant | No |
| CFR parts | 14 CFR 71 |
| Summary | This action corrects a final rule published by the FAA in the Federal Register on August 3, 2026, establishing United States Area Navigation (RNAV) Route T-581 in the vicinity of Missoula, Montana. Specifically, this action corrects the description of the route in the regulatory text of the final rule. |
| Document number | 2026-19173 |

## Why this score
- Final rule.

Source: Federal Register API (Office of the Federal Register) (https://www.federalregister.gov/documents/2026/09/18/2026-19173/establishment-of-united-states-area-navigation-route-t-581-in-the-vicinity-of-missoula-montana). Last refreshed: 2026-11-04T09:17:43.641Z.
Data from the Federal Register API; the published Federal Register document is authoritative. Informational only, not legal advice.