Incident Overview
On July 16, 2025, about 1542 eastern daylight time (EDT), SkyWest Airlines (SKW) flight 3751, a Bombardier CL-600-2D24 (registration N833SK), departed from a closed runway at MBS International Airport (MBS), Freeland, Michigan. The flight proceeded without further incident to its intended destination of Detroit/Wayne County International Airport (DTW), Romulus, Michigan. The aircraft carried 2 flight crewmembers, 2 cabin crewmembers, and 61 passengers, all of whom deplaned at the gate without any injuries. The flight was operated as a Title 14 Code of Federal Regulations Part 121 scheduled domestic passenger flight. The National Transportation Safety Board (NTSB) was notified by the Federal Aviation Administration (FAA) and began an incident investigation.
Flight Crew Actions
According to SkyWest, the dispatch release for the incident flight was 20 pages long and indicated a departure time of 1533, with an 18-minute taxi out at MBS and an estimated time of arrival at DTW of 1622. The captain had arrived from DTW as a dead-heading crewmember and met the crew at the gate. Prior to departure, the first officer, who was to be the pilot flying (PF), conducted the threat briefing. Both pilots discussed storms in the vicinity and decided that if good takeoff data were obtained, they would depart from runway 14. The flight crew reviewed the taxiway closures provided by the dispatcher, and the captain highlighted applicable ones on the airport diagram. The crew received takeoff data for runway 14 and, considering potential windshear, agreed to use normal takeoff performance numbers.
The MBS air traffic control tower (ATCT) was closed via a notice to airmen (NOTAM) at the time of pushback. After completing the engine start checklist, the first officer contacted Great Lakes approach control for their air traffic control clearance to DTW. The crew reported making appropriate advisory transmissions on the MBS common traffic advisory frequency (CTAF) while taxiing to runway 14 via taxiways C and A. During taxi, the crew noted no visible cues indicating closure of taxiways or runways. While holding short of runway 14, the first officer contacted Great Lakes approach control and informed the controller they were number one at runway 14 and ready for departure. The controller issued a release of "fly runway heading maintain 4,000." The crew reported no obstructions or airport personnel at the time of departure. According to ADS-B data, the flight became airborne at about 1542:39. The crew stated the flight was uneventful, with no indication they had departed from a closed runway. ADS-B data showed the flight landed at DTW about 1607.
NOTAM Information
A review of NOTAMs for MBS revealed 18 NOTAMs in effect at the time. One NOTAM specified that runway 14/32 was closed from July 16, 2025, beginning at 0600 until 1800. On page 14 of the dispatch release, under "Origin Airport NOTAMS," the NOTAMs were divided into six sections. Three sections were titled "Aerodrome/RWY/FICON NOTAMS," "Taxiway and Airport Lighting NOTAMS," and "Radio/Communication NOTAMS." The "Aerodrome/RWY/FICON NOTAMS" section contained five NOTAMs, including the runway 14/32 closure NOTAM. The "Taxiway and Airport Light NOTAMS" section also had five NOTAMs, and the "Radio/Communication NOTAMS" section had one.
Airport Information
MBS International Airport is located about 9 miles northwest of Saginaw, Michigan, at an elevation of 668.2 feet msl. The airport has two paved runways: 05/23, which is 8,002 feet long and 150 feet wide, and 14/32, which is 6,399 feet long and 150 feet wide. According to the FAA Chart Supplement, the MBS ATCT normally operates daily from 0700 to 0000. At the time of the incident, the ATCT was closed via a NOTAM from July 16, 2025, at 0957 until 2300.