Cape Air Flight Returns to Nantucket After Cabin Door Opens Midflight

A small Cape Air commuter plane bound for Boston turned back to Nantucket Memorial Airport on Monday after the upper portion of its main cabin door opened in flight, giving passengers an unobstructed view of open sky and ocean through the door frame as the aircraft crossed Nantucket Sound.

Cape Air flight #5001, a 9-passenger Cessna 402C, had just departed Nantucket Memorial Airport on the morning of April 7, 2026, when the door malfunction occurred. The crew maintained control of the aircraft and diverted back to the island without further incident. No injuries were reported, and passengers were transferred to a replacement aircraft to complete their trip to Boston Logan International Airport.

Lizbet Fuller, a Nantucket island resident who was aboard for the first leg of a trip to Virginia, filmed the incident and posted the video to Instagram. The footage appears to show the door gap clearly, with sky and ocean visible through the opening as the plane remained airborne. "The pilot was amazing and made everyone feel calm," Fuller told The Nantucket Current. "It was a bit nerve-wracking even though I'm smiling." Her Instagram caption delivered a dryer verdict: "Just another flight from Nantucket."

Cape Air spokeswoman Mary Stanley confirmed the incident in an official statement, noting that flight #5001 "experienced an issue in which the upper portion of the main cabin door opened while in flight" and that "the aircraft continued to operate normally." The airline confirmed the plane was taken out of service for evaluation. "We are following all established safety procedures and will take any necessary actions based on our findings," Stanley said. "The safety of our passengers and crew remains our top priority."

The FAA has opened a formal investigation into the door malfunction. Investigators will scrutinize the latch mechanism, maintenance logs, and whether preflight door checks were properly completed. The aircraft will undergo a full structural and mechanical inspection before any return to service.

Understanding why the outcome was not worse requires a closer look at the aircraft itself. The Cessna 402C is non-pressurized, which means it flies at lower altitudes than large commercial jets and does not sustain the cabin-to-atmosphere pressure differentials that make door failures on those aircraft explosive and potentially catastrophic. When a door plug blew out on an Alaska Airlines Boeing 737 Max 9 in January 2024, the pressure differential was enormous. On a Cessna 402C cruising over Nantucket Sound, a partial door opening is alarming but does not trigger the same structural cascade. The crew retained full control throughout.

The Cessna 402C involved is a design that dates to 1967, manufactured through 1985, with FAA certification granted in January 1969. Cape Air, the largest independent regional airline in the United States, calls the 402 "the workhorse" of its fleet and operates more than 60 of the aircraft across its network covering the Northeast, the Caribbean, and Eastern Montana. The ground temperature at Nantucket at the time of departure was 46°F, a detail investigators may weigh when assessing door seal and latch performance under cold conditions.

This is not the first time a Cape Air Cessna 402C has made headlines for an in-flight emergency. On September 17, 2024, another of the airline's 402Cs returned to Boston Logan after landing on one wheel. In September 2021, a 402C carrying one crew member and six passengers crashed into trees on approach to Provincetown Airport, causing burns and broken bones but no fatalities. The incidents, spread across years, keep renewed focus on the operational demands placed on an aging aircraft type that remains the backbone of essential commuter service to communities like Nantucket, where small regional planes are the primary alternative to a ferry.

Founded in 1988 by pilots Craig Stewart and Dan Wolf alongside investor Grant Wilson, Cape Air built its business on exactly these thin-margin, high-frequency island routes. Investigators now have the task of determining whether Monday's door failure reflects a maintenance gap, a latch design vulnerability, or an isolated mechanical failure in an otherwise reliable aircraft.