On July 30, 2025, Delta Air Lines Flight 56 departed Salt Lake City on an international flight to Amsterdam. Less than an hour later, after the pilots flew into an area of severe convective activity over Wyoming, the Airbus A330 encountered severe turbulence, and the pilots lost control of their aircraft.
That turbulence and the pilots’ subsequent loss of control of the aircraft violently threw passengers and flight attendants through the cabin and injured many. The flight was forced to divert to Minneapolis to seek emergency medical treatment.
For those of us who represent people injured in aircraft accidents, the facts emerging from Delta 56 are troubling not because they are unusual, but because they are familiar.
They closely resemble what occurred on Hawaiian Airlines Flight 35, on December 18, 2022, a case in which ALG represents many of the injured passengers and one that the National Transportation Safety Board ultimately confirmed involved a flight crew flying into known hazardous weather rather than avoiding it.
Delta 56 appears to follow the same pattern, and Aviation Law Group is representing injured passengers on Flight 56 in their claims against Delta.
The Delta 56 Turbulence Event
According to the NTSB’s preliminary investigation, Delta Flight 56 encountered severe turbulence while cruising at approximately 37,000 feet near Creston, Wyoming.
The turbulence was strong enough to disengage the autopilot, rapidly force the aircraft above and below its assigned altitude, and subject occupants to substantial vertical acceleration forces.
Preliminary flight data shows vertical accelerations approaching 1.75g positive and minus 0.5g negative, with rapid climbs to 38,000 feet followed by abrupt descents. Airspeed fluctuated dramatically, pitch oscillated from nose-down to nose-up, and roll excursions reached extreme values.
The upset lasted approximately two and a half minutes. This was not a brief bump or momentary disturbance. It was a sustained encounter with severe atmospheric forces.
Neither the passengers nor the flight attendants had any warning of the impending loss of control. There was no seatbelt sign, and the beverage cart was in the middle of service. As a result, the cart, flight attendants, and passengers were forcefully thrown into the cabin ceiling. Multiple flight attendants were injured, including two who suffered serious injuries. Passengers were also seriously injured, prompting an emergency diversion to Minneapolis, where medical personnel met the aircraft. At least twenty-five of those on board were transported to local hospitals for evaluation and care. The cabin interior sustained substantial damage.
Weather Was Forecast, Known, and Warned About
The most important similarity between Delta 56 and Hawaiian Airlines Flight 35 lies in the weather environment.
At the time of the Delta 56 turbulence encounter, a convective SIGMET was in effect for the area. A SIGMET is a severe weather advisory concerning the safety of all aircraft that is issued by the National Weather Service. That SIGMET warned of thunderstorms with cloud tops above FL450 and the potential for severe turbulence. These are precisely the conditions pilots are trained to avoid laterally rather than fly over.
Flight crew statements confirm that turbulence along the route was anticipated. The crew discussed weather conditions prior to departure and expected to deviate if necessary. During the climb, they experienced turbulence over the Wasatch Mountains and later observed weather buildups ahead. Despite this, they apparently continued toward developing convective weather, accepting a heading change they assessed would keep them above the cloud deck and clear of the worst conditions. That assessment proved incorrect.
This sequence of decisions mirrors what the NTSB confirmed in its final report on Hawaiian Airlines Flight 35. In that case, the crew also had access to weather forecasts, SIGMETs, radar information, and visual cues indicating severe weather. The NTSB ultimately concluded that the flight crew flew into an area of severe turbulence associated with a convective cloud that should have been avoided.
Severe Turbulence Is Not Automatically Unavoidable
Airlines frequently describe turbulence injuries as unavoidable acts of nature. The investigations into HA35 and now Delta 56 challenge that narrative.
Modern airline crews operate with multiple layers of weather information, including dispatch briefings, onboard radar, satellite data, SIGMETs, and pilot reports. When convective activity is forecast and visible, severe turbulence is not a surprise. It is a known and foreseeable hazard.
In the HA35 case, the crew had been briefed about severe weather en route, had heard other aircraft in the area report the conditions, and had seen the developing weather, but did not deviate from its course to Honolulu. In Delta 56, early facts suggest the aircraft encountered convective weather in an environment where warnings were already in place and other aircraft were maneuvering around storm systems.
Amazingly, both flights involved the same type of aircraft, an A-330 that was operating near the top of its performance ceiling. This left the pilots with little room to control the aircraft. In HA35, the flight data indicates that the aircraft entered a stall as it was pushed up by turbulence, and the pilots fought to regain control. In this instance, the lengthy period the pilots fought to regain control suggests a similar situation.
International Flight Means Montreal Convention Liability
Delta Flight 56 was an international flight from the United States to the Netherlands. As such, many of the passengers were likely on international itineraries, which should make many of the injury claims arising from this accident governed by the Montreal Convention.
The Montreal Convention imposes strict liability on international air carriers for passenger injuries up to a defined threshold, without requiring proof of negligence. Above that amount, the airline must prove that the injury was not caused by its negligence or was solely caused by a third party.
In turbulence cases, airlines often argue that they were not negligent because weather is an external force beyond their control. However, that argument becomes far weaker when the evidence shows that severe weather was forecast, warned about, and avoidable through reasonable operational decisions.
The NTSB is continuing its investigation and will likely provide its final report within two years of the accident. During its investigation, it will review the full flight data and cockpit voice recorders, interview the pilots, crew, dispatchers, and passengers.
In the meantime, Aviation Law Group is actively seeking information about this accident for its own investigation and to support passengers who were on the flight with their legal claims. If you or anyone you know was aboard DAL 56, please contact us at info@aviationlawgroup.com or call 206-249-9975.