The aircraft, a Gulfstream G100 operated by Canadian medical evacuation company Latitude Air Ambulance, disappeared from radar at about 1:30am on Saturday, according to the Federal Aviation Administration. Air traffic controllers had reported difficulty communicating with the pilot in the final moments before the loss of contact.
Audio captured by LiveATC.net included a controller asking the pilot, "You're coming in blind? Is that what you said? Are you declaring an emergency, or no?" The pilot's response was not audible. Radio transmissions also recorded discussion of electrical failures as the plane neared Nantucket. Flight tracking data from FlightAware shows the aircraft plummeting thousands of feet in the three minutes before it vanished from radar.
An initial Coast Guard search located a debris field confirmed to be associated with the missing aircraft. "Coast Guard search crews located a debris field that has been confirmed to be associated with the missing aircraft," a spokesperson said in a press release at the time. "Crews are continuing to search for the six people who were aboard the aircraft."
The search was called off a day later. "Suspending a search is not an easy decision," Coast Guard Rear Admiral Matthew Lake said in a statement. "We express our deepest condolences to the families and loved ones affected by the tragedy and our gratitude for our partner agencies who helped support search efforts."
The Coast Guard identified the six presumed dead as four Canadian crew members and two Bermudian passengers, including the injured patient being evacuated and a family escort.
Latitude Air Ambulance acknowledged the suspension and the presumed loss. "Given the information shared by authorities and the conclusion of the search and rescue phase, we must now face the heartbreaking reality that the four members of our Latitude team, our patient and the patient's family escort, who were aboard Heartbeat 104, are presumed to have died," the company said. Latitude said it will "cooperate fully" with the US National Transportation Safety Board and the Transportation Safety Board of Canada on recovery efforts and investigations into the plane's presumed crash.