DENVER (KDVR) — When a United Airlines plane was dynamited, exploding in the sky over Colorado 70 years ago and killing 44 people, the unprecedented act set the tone for future FBI investigations into aviation disasters.
“It wasn’t just a crime against 44 innocent souls. It was a turning point, really, in the history of aviation,” said Mark Michalek, Special Agent in Charge of the FBI’s Denver office.
“It’s a tragedy that led to meaningful reforms and changed the aviation industry,” he told FOX31.
This was the first act of sabotage on a domestic aircraft.
“There was no evidence of that,” Michalek said. “The agents just got the job done.”
This was the first time some investigative techniques had been used.
“This was a decisive and defining moment in the history of the FBI,” he said.
The FBI documented the victims and reviewed the wreckage
The FBI’s role was to take fingerprints, identify victims, review the wreckage, look for clues about the cause, and do something that had never been done before but is now standard in aviation disasters: reconstruct the plane to understand why it went down.
“To be able to bring it back to Stapleton Airport and basically recreate the fuselage in a mock-up, to put the pieces together like a jigsaw puzzle. While building that fuselage, they were able to determine where the cause of the initial accident was. The point of impact, where the damage was the most, was just the luggage. From there, they were able to find the luggage and pair it with the families of the victims to determine that. There was some luggage that had not been touched. There was some that had remains, and some of it, like Miss Daisy King,” Michalek said. “It was completely obliterated, indicating that it was the point of explosion.”
That’s how they discovered that her son, John “Jack” Gilbert Graham, 23, had put the bomb in her purse.
Don Sebesta was one of the lead FBI investigators in this case. His son, Jim Sebesta of Littleton, was just a newborn at the time of the investigation, but his father’s scrapbook is full of news articles from the trial.
“My mom got it after he passed. She decided to donate it to the office,” Sebesta told FOX31.
The clippings help fill in the details of the crime investigation and trial, unlike anything Colorado has ever seen. A trial that received international attention.
“From what I can tell, this was like the OJ Simpson trial in the 1950s,” Sebesta said.
“This was the first time in Colorado that they were allowed to put cameras in a courtroom, and it was the first time in the way forensic evidence was prepared,” he said.
Investigators dig into the suspect’s life and obtain the death penalty
In the course of their criminal investigation into the incident, agents zeroed in on Graham after discovering that he had taken out insurance policies on his mother’s life moments before the flight. At that time, you could buy life insurance at an airport kiosk. In his garage, they found bomb-making materials similar to those used to bring down Flight 629.
They also learned that Graham and his mother, Daisy King, fought like cats and dogs, and that he had an extensive criminal record. Faced with a mountain of evidence collected by the FBI, Graham confessed to the crime, but later recanted it. In a trial that captured the nation’s attention, he was convicted of murder and sentenced to death. Graham was executed in the gas chamber at the state prison in Cañon City on January 11, 1957.
“Our hearts go out to all the victims and their families. This is really the focus,” Sebesta said.
He says one of the lasting legacies of the Flight 629 bombing investigation is the meticulous work done by law enforcement and the exemplary work of the FBI.
“I would say, without hesitation, it is the most professional organization I have ever known,” Sebesta told FOX31.
Clearly, the office felt the same way about his father. In his father’s scrapbook, there is a letter written by famous former FBI chief J. Edgar Hoover, praising Don Sebesta for his exemplary work investigating Flight 629.
“The FBI director sent a letter to one of the agents on the case thanking him for his work,” Michalek said.