Only minutes into a doomed journey that ended on a remote Virginia mountain, the pilot of a business jet was not responding to air traffic control instructions and the situation was soon reported to a network that includes military, security and law enforcement agencies, according to federal aviation officials.
Despite being out of contact on its ascent Sunday afternoon, the jet that had just taken off from a Tennessee airport continued toward its intended destination on Long Island, then turned to fly back to Virginia where it slammed into a mountain, killing the four people aboard.
Family and friends identified two of the victims as an entrepreneur known in New York real-estate circles and her 2-year-old daughter.
Outside aviation experts continued to speculate that the pilot likely lost consciousness from a lack of oxygen inside the jet when it climbed above 10,000 feet, the altitude that typically requires cabin pressurization.
"The most likely scenario right now is a pressurization failure or a mis-setting of the pressurization system," said Alan Diehl, an aviation psychologist who previously worked for the Federal Aviation Administration, the National Transportation Safety Board and the U.S. Air Force. In the late 1960s, Diehl also helped design the original model of the plane, the Cessna Citation, that crashed in Virginia.
It's unclear when the pilot stopped responding to air traffic controllers. But their last attempt to reach him occurred 15 minutes after takeoff, according to the FAA.
The plane could have surpassed 10,000 feet in just a few minutes, Diehl said. However, the pilot may have had to wait for some period of time after takeoff before he was cleared for higher altitudes.
Depending on the jet's altitude as well as the pilot's age and health, he likely had minutes — or even less than a minute — to react as his brain suffered a decline in oxygen, Diehl said.
"The one other thing that they probably can’t eliminate at this point is some kind of medical issue," Diehl said.
A heart attack, brain aneurysm and over-the-counter medications, such as antihistamines, can affect a pilot's ability to fly the airplane and recognize there may be a problem with the cabin's oxygen levels and pressurization.
Fighter jet pilots sent to intercept the business jet reported that its pilot appeared slumped over and unresponsive, three U.S. officials said Monday. The officials had been briefed on the matter and spoke on condition of anonymity because they were not authorized to discuss details of the military operation.
The plane took an erratic flight path — turning around over Long Island to fly directly over the nation’s capital — which prompted the military to scramble fighter jets. This caused a sonic boom heard in Washington, Maryland and Virginia.
On Monday, it took investigators several hours to hike into the rural area where the plane crashed about 60 miles southwest of Charlottesville. They expect to be on the scene for at least three to four days.
Diehl, the aviation psychologist, said investigators often dig deeply into a pilot's background following a crash. For instance, did he or she have training in the military to recognize the signs of low-cabin pressure? Were they a risk taker? What were the results of their last flight physical?
Investigators will also review the recordings of the pilot's last communications with air traffic control. They'll check for a change in speech patterns, such as slower talking, that could indicate low-oxygen levels. But testing oxygen levels in blood and human tissue could be unlikely given the high impact of the crash, Diehl said.
At a briefing Monday, NTSB investigator Adam Gerhardt said the wreckage is "highly fragmented" and investigators will examine the most delicate evidence at the site, after which the wreckage will be moved, perhaps by helicopter, to Delaware, where it can be further examined. It was not clear if the plane had a flight data recorder. A preliminary report will be released in 10 days.
The Virginia State Police said human remains will be brought to the state medical examiner's office for autopsy and identification. Authorities said the victims included the pilot and three passengers. There were no survivors.
The plane took off from Elizabethton Municipal Airport in Tennessee at 1:13 p.m. Sunday, headed for MacArthur Airport on Long Island, New York. Air Traffic Control lost communication with the airplane during its ascent, according to the NTSB.
Preliminary information indicates the last air traffic control communication attempt with the airplane was at approximately 1:28 p.m., when the plane was at 31,000 feet, the NTSB said. About eight minutes later, the FAA reported the situation to the Domestic Events Network, which includes military, national security, homeland security and other law enforcement agencies.
The plane climbed to 34,000 feet, where it remained for the rest of the flight until 3:23 p.m. when it began to descend and crashed about nine minutes later, according to the NTSB. The plane was flying at 34,000 feet (10,363 kilometers), when it flew over MacArthur Airport at 2:33 p.m., the NTSB said.
The plane flew directly over the nation's capital. According to the Pentagon, six F-16 fighter jets were deployed to intercept the plane, including two from a base in Maryland, two from New Jersey and two from South Carolina.
PROMINENT FLORIDA FAMILY LINKED TO PLANE THAT FLEW OVER DC, CRASHED IN VIRGINIA MOUNTAINS
The plane that crashed was registered to Encore Motors of Melbourne Inc in Florida. John Rumpel, a pilot who runs the company said his family was returning to their home on Long Island, after visiting his house in North Carolina.
In interviews with the New York Times and Newsday, Rumpel identified his daughter, Adina Azarian, and 2-year-old granddaughter Aria, as two of the victims.
Azarian, 49, was well-known in real estate circles in New York, described by friends and relatives as a fiercely competitive entrepreneur who started her own brokerage and was raising her daughter as a single parent.
"Being a mom was everything to her," said Tara Brivic-Looper, a close friend who grew up with Azarian. "That they were together (at the end) is fitting."
Friends say Azarian moved to East Hampton fulltime to raise Aria, with the help of a nanny. But she made frequent trips back home, bringing both Aria and the nanny to meet her tight-knit extended family on multiple occasions in recent months.
"She seemed so happy out there," her cousin, Andrew Azarian, recalled. "Both of their lives hadn’t even started."
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"How could this happen?" he continued. "No one can explain it."