A 1955 Plane Crash Had a Sinister Reason Behind It

Airport officials and authorities were baffled when on November 1, 1955, United Airlines Flight 629 exploded just minutes after leaving the tarmac. The airplane had been in perfect condition and successfully completed two flights earlier that day. Initial investigations proved fruitless, and it appeared the crash might remain unsolved. That is until investigators found a victim’s handbag.

A United DC-6 at Stapleton Airport, similar to the aircraft involved
A United DC-6 at Stapleton Airport, similar to the aircraft involved. Source: Wikipedia

This particular handbag, belonging to a Mrs. Daisie King, contained some very strange and fruitful leads involving someone very close to her: her son. What did Mrs. King have in her handbag? And what did authorities find that led them to believe that her own son planned his mother’s death by means of a plane crash? Well, you’re soon to find out.

This is the true story of a boy who planned his own mother’s demise – as well as that of 43 others…

A Ball of Fire… at Dinner

It was a regular day in Longmont, Colorado, when a man named Conrad Hopp sat down for dinner with his family on November 1, 1955. As the Hopp family were enjoying their meal in the house on the farm Conrad grew up on, something suddenly startled them. Hopp, then 18 years old, heard “this loud explosion that shook all the windows in the house.”

wreckage United Airlines Flight 629
wreckage United Airlines Flight 629. Source: thedenverchannel.com

“We looked outside, and we could hear the roar of the engines — that’s how you knew it was a plane — and the ball of the fire coming through the air.” Conrad and his brother immediately ran outside, just in time to lose sight of the flaming wreckage behind the far buildings on the farm.

Racing to the Wreckage

The Hopp brothers then jumped in Conrad’s truck, a ’54 Chevy, and raced across the fields of alfalfa, dodging the falling debris that was coming down from the sky. They got to an irrigation ditch and a patch of trees, so Conrad parked as his headlights were shining a light on the back of an airline seat.

wreckage United Airlines Flight 629
wreckage United Airlines Flight 629. Source: Pinterest

The night was just settling in, and it was chilly. Conrad’s brother climbed over a fence and ran straight towards the wreckage. “Go get some coats!” he yelled to Conrad. But it was at this point in his recollection that Conrad had to stop himself. “I’m sorry,” he said. “I can’t do this.” It was understandably tough for Hopp to remember seeing a body still strapped into the seat by the seatbelt.

11 Minutes After Take-Off

At 6.52 p.m. on November 1, 1955, the DC-6B aircraft took off from Denver’s Stapleton Airport bound for Portland, Oregon. Initially, everything went smoothly aboard the flight. Four minutes into the trip, the captain radioed in a message to the airport’s control tower, informing the ground crew that things were going as planned.

wreckage of United Airlines Flight 629, tale wing
wreckage United Airlines Flight 629. Source: Twitter

According to the accident report from the Civil Aeronautics Board, seven minutes after that message, at 7.03 p.m., Stapleton International Airport’s air traffic controllers witnessed two bright flashes of light in the sky. About a minute later, those watching realized that the two lights were beginning to tumble through the air and fall down to the ground.

It Lit Uup the Eastern Skies

There’s no doubt that staff members overlooking Flight 629 were expecting the worst. The plane’s freefall through the air was then followed by a massive explosion on the ground. Immediately, the air traffic controllers rushed to touch base with every single plane in the Stapleton airspace. Flight 629 happened to be the only flight that didn’t respond.

Headlines from Detroit Paper, 1955.
Source: Twitter

Keith Cunningham, Longmont’s police chief at the time, dispatched every police officer, firefighter, and ambulance in the city to the location of the wreckage. No one knew exactly where the aircraft was. Phone calls from the town of Longmont were coming in, though, which was about 30 miles from the airport. The town’s residents were reporting a loud explosion and metal debris raining down on them.

No Ambulances Necessary

In the moments following the explosion, hundreds of calls flooded the Longmont Police Department. Thousands began to flock to the area on foot, curious as to what this “ball of fire that lit up the eastern skies for miles” was. They found the plane scattered across six square miles of Weld County. Local authorities began searching among the debris, desperately hoping that at least a few passengers had survived.

wreckage of United Airlines Flight 629, tale wing
Source: Pinterest

The plane blew up 5,780 feet above ground, over farmlands eight miles east of Longmont. The wreckage was scattered across six square miles, where now Interstate 25 meets Colorado 66. Sadly, when they arrived on the scene, they were left speechless. A few minutes later, a patrolman radioed back: “No ambulances are necessary.”

United Airlines Flight 629

The explosion of United Airlines Flight 629, which occurred 65 years ago, happened to be one of the first attacks on a commercial airliner in American history. It was also the deadliest mass murder in Colorado history, taking the lives of all 44 people on board. First responders were quick to discover and report that the flight’s five-person crew and 39 passengers, including a 13-month-old boy, were all killed instantly in the explosion.

wreckage of United Airlines Flight 629, tale wing
Source: coloradomartinis.com

About two miles south, Martha Hopp, Conrad’s girlfriend at the time, was also sitting down for dinner with her family when the explosion happened. She and her father, like everyone else in the town, ran outside and rushed toward the wreckage. “When we looked around, every road was lights,” Martha said.

Searching for the Bodies

“Up on the hills, everywhere you looked, there were lights because everyone was doing the same thing –going to see what happened.” Less than a mile up the road, they started to see silverware from the plane littered across the ground. Then they saw letters, pieces of paper, and dinner trays. Martha joined Conrad and spent the night looking for bodies.

Place of crashing - United Airlines Flight 629
Source: Twitter

They found one victim who fell into a straw pile after Conrad helped to split the pile apart to find the body. Martha decided to mark where the bodies were found by driving in circles around them. “At that point and time, you don’t even realize what you’re experiencing… until after the fact,” Conrad explained.

Combing the Fields

“When you try to think about it later, it bothers you. It takes its toll.” The Rocky Mountain News reported a “scene of death and horror under flickering flames,” with searchers in a state of “shocked daze.” Hundreds of people searched in the beet field between Longmont and Platteville. Reporter Jack Gaskie wrote: “There were certain things to do – cover the bodies, make futile efforts to quell the flames of the fiercely burning wreckage.”

wreckage of United Airlines Flight 629, the plane body
Source: coloradomartinis.com

“But for the most part, they stood around in quiet, stunned groups, waiting.” As Martha went to high school the following day, Conrad kept helping. He said hundreds of volunteers formed a line, at about an arm’s length apart, and walked across the massive fields, combing the ground for every single piece of the wreckage.

Piecing it All Together

According to the Civil Aeronautics Board report, the tail of the plane landed 4,600 feet southeast of the motors and the wings, which upon impact created deep craters. The front of the aircraft landed 600 feet to the north of the craters. And another wing panel landed 600 feet to the south of them. The rest was scattered across the fields.

wreckage of United Airlines Flight 629
Source: Twitter

The process became even more meticulous once the pieces of the wreckage were taken to a warehouse at the Stapleton Airport. There, investigators reconstructed the body of the plane around a frame of chicken wire. They attempted to piece together hundreds of scraps from the disintegrated aircraft. It was the only way to fully visualize where the source of the explosion was.

A “Dynamite-Type” Blast

It didn’t take long for it to become clear that an explosion of “such great intensity” wasn’t actually a malfunction of the plane, as the Civil Aeronautics Board reported. It was discovered that shards of sheet metal were tainted with traces of chemicals that are typically used to create dynamite.

The explosion mechanism used by Gilbert
Source: Pinterest

Within days, investigators were able to pinpoint the source of the explosion: a “dynamite-type” blast in baggage compartment No. 4, which was located in the cargo hold. This revelation, which came six days after the crash, meant that the Civil Aeronautics Board had to contact the FBI. It was now a criminal investigation. Authorities assumed that someone smuggled a bomb on board, but they struggled to put their finger on a motive that would make someone do such a thing.

The Luggage with the Most Destruction

While investigators combed through the wreckage, another team started the long task of compiling background information on each and every one of the 44 victims. Part of that investigation included determining which luggage belonged to which passenger, and comparing that information with how much of their baggage was destroyed.

Daisie E. King
Daisie E. King Source: Twitter

This would allow the FBI to narrow down the search to which passengers had the most badly damaged luggage. One passenger whose luggage was practically destroyed was Daisie E. King, a 54-year-old woman from Denver. Soon after, investigators learned that the blast turned out to be a culmination of a young man’s anger toward his mother, who was on that flight and brought aboard 25 sticks of dynamite in her suitcase. She just didn’t know it.

Daisie King: an Unlikely Suspect

During the investigation, the one passenger who stood out from the rest was Denver resident Daisie King. On paper, the woman seemed far from being able to raise any eyebrows. You would probably even point her out as one of the least likely to bomb a plane full of people. The middle-aged woman was a widow and a business owner.

wreckage of United Airlines Flight 629 in a hangar
Source: YouTube

Basically, she was someone who had something to lose. She was on that flight because she was heading to Alaska to visit her daughter. However, although most of her luggage was blown to bits, there was one detail about Daisie that struck the FBI. They happened to find something near and dear to Mrs. King that somehow survived both the explosion and the plane crash.

Newspaper Clippings of the Man in Question

When she boarded the flight, King was carrying several items with her. The FBI were able to recover King’s personal letters, her personalized checkbook, $1,000 in traveler’s checks, two keys for safe deposit boxes, an address list, and something else that stood out. In her purse were several newspaper clippings that featured John “Jack” Gilbert Graham.

John “Jack” Gilbert Graham
John “Jack” Gilbert Graham. Source: YouTube

Graham was known to be a small-time criminal, and her relation to this man seemed very out of the ordinary, and immediately caught the FBI’s attention. Graham wasn’t a first-time offender by any means. In fact, much of his criminal past could be chalked up to his abnormal upbringing. And the man just so happened to be Daisie King’s 23-year-old son.

They Fought Like Cats and Dogs

As the newspaper clippings revealed, Graham had been charged with forgery a few years prior and was placed on a “Most Wanted” list by Denver County’s District Attorney. The plane crash investigation quickly changed direction to focus on King and her son, especially since they discovered the tense history between the mother and her son.

wreckage of United Airlines Flight 629
Source: Twitter

The FBI learned that Graham was set to receive an inheritance, but the mother and son argued for years about it. According to the FBI, the two “fought like cats and dogs.” To understand a bit more about such a confusing case, a little history might be of help. John Gilbert Graham was born in 1932…

Left in an Orphanage

The boy was Daisie’s only child from her second marriage. Unfortunately, the kid wouldn’t get the love and support that every child needs. Not long after John was born, his father died. Without the means to support him, his mother felt that her only option was to put him in an orphanage. After giving him up, she tried to find a way to get back on her feet.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

While it’s only natural to assume that Daisie would try to get her son back and into her home, that’s not what she did. Instead, she simply moved on with her life. She married for the third time and seemingly enjoyed the stability her new life brought her.

Moving on With Her Life

Despite a new-found stable life, Daisie never brought her son back from the orphanage. Daisie’s third husband eventually passed away, too, and she was left with an impressive inheritance. She decided to use the money to open up a restaurant. She called it the Crown-A Drive-In Diner. It became a local success, and she built a nice group of loyal customers.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

By 1954, Daisie was now a restaurant owner but didn’t quite know what to do with herself. She was a widow and her daughter was living in Alaska. She couldn’t think of a better moment to track down her long-lost son and hopefully pick things up where they left off 22 years earlier.

A Life of Crime

And so 22 years after the young John was sent to the orphanage, he and his mother would cross paths again. Their reunion took place just a year before the plane crash. And while most people wouldn’t rush into paying his or her abandoned child, Daisie must have had a great deal of guilt for what she did all those years ago.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

She put him in the hands of strangers and discovered that her own flesh and blood turned to a life of crime. She learned that his arrest record included offenses like embezzlement, forgery, and bootlegging. She was sure that if things had gone differently if she had been there to guide him, his future would have been different.

Making Him the Beneficiary

John lived with various family members throughout his early years, but eventually ran away when he was 16. He later returned to Denver, and upon reuniting with his mother, she gave him the responsibility of running the restaurant. With such feelings of guilt, Daisie then did something that others would regard as foolish. As FBI agents dug deeper, they learned that not long before the crash, Daisie made John the beneficiary of her life insurance policy.

Daisie E. King
Daisie E. King. Source: thedenverchannel.com

Something even more peculiar was the fact that her restaurant had sustained some damage in a recent explosion. It turns out that this mother and son duo stood to receive a sizable insurance payout. One witness also told investigators that John might have been embezzling money from the business.

All Signs Pointing to Graham

In September 1955, two months before the plane explosion, another mysterious blast damaged Daisie King’s restaurant. Graham had blamed it on a disconnected gas line. But that same year, his brand new 1955 Chevrolet pickup truck was found stalled on a railroad track and struck by a train. He blamed that incident on mere bad luck.

wreckage of United Airlines Flight 629
Source: thedenverchannel.com

This was evidence that simply couldn’t be ignored. John Gilbert Graham immediately became the FBI’s prime suspect. Knowing that he was going to receive a large sum of money, John was likely eager to cash in following the crash. His apparent plan to blow up the plane with his mother on it was so cunning that he never expected that newspaper clippings would be the evidence that led the FBI to his door.

Knock, Knock

When the FBI came knocking on John Graham’s door, he was quick to claim that he had nothing to do with the plane crash. But the evidence in his home told a much different story. The criminal wasn’t very good at covering his tracks. As investigators searched the home, they found a bunch of life insurance policies.

John Graham and a policeman
Source: thedenverchannel.com

But it was what they found in his garage that clearly indicated Graham as the main suspect. When FBI agents entered Graham’s garage, they uncovered all the materials needed to create a bomb big enough to destroy a commercial plane. The thing is, Graham had a perfect alibi: he said his mother packed her own luggage.

He Said He Loved His Mother

But none of the investigators truly believed that Mrs. King wanted to blow up a plane. When asked about his mother’s trip to Portland, Graham offered little information. He just told them that his mother was going to visit his sister. He claimed that he didn’t have any clue as to what she packed in her luggage, other than the shotgun shells and ammunition for “hunting caribou.”

John Graham
Source: thedenverchannel.com

Graham even went on to say that he loved his mom and would never want to hurt her. Those who knew them, on the other hand, wouldn’t describe the mother-son relationship as loving. Witnesses recalled seeing the recently reunited pair fight regularly. It appeared to them that there was some intense resentment between the two.

Talking to His Wife

Graham swore that his mother had packed her own bags that day – and if there was a stick of dynamite in there, it was because she put it there herself. But his alibi was soon shot down…by his own wife. Investigators started to interview Graham’s wife, Gloria. She provided them with some background on them as a couple.

Picture of all the victims of flight 629
Source: thedenverchannel.com

They got married in 1953 and were parents of two young children. They lived in the Lakewood area, on Mississippi Avenue, after having shared the home with Graham’s mother for a year. Gloria said that she was unaware of what King might have packed for her trip. But she did offer interesting detail.

The Day of the Flight

On the day of the crash, as Gloria described, Graham was planning to give his mom an early Christmas gift, which she believed to be a set of small tools. Gloria told the investigators that he searched all day for the gift. He then brought the package into the house and took it to the basement, where his mother was busy packing her luggage.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

Gloria said she didn’t know if Daisie ever received the package, but assumed she did. When she finished packing, the family loaded the luggage into Graham’s 1951 Plymouth and headed to the airport. The day after Graham and his wife were interviewed by the FBI, they called the couple back for more questioning.

She Broke

The FBI received a few tattered pieces of luggage that they believed belonged to Daisie King. So they asked John and Gloria to come to the headquarters in Denver. The couple agreed, and while at the office, they identified the bag belonging to King. Gloria eventually broke and admitted that she saw her husband pack his mother’s bags before her flight.

Summary report about United Airlines Flight 629 investigation
Source: thedenverchannel.com

Afterward, the agents told Gloria that she could leave, but Graham was to stay behind for more questioning. With Graham alone, the agents then questioned him about the toolset “gift” that Gloria said he bought for his mother. Why didn’t he mention it to them before? They also asked him why, at the airport, did he buy a trip insurance policy in his mother’s name?

Finding More Evidence

Furthermore, they wanted to know why he reportedly got sick after her plane took off. Graham offered to take a polygraph test and even gave the agent permission to further search his property. They ended up finding a small roll of copper wire – similar to the wire found on the detonating primer cap – inside one of Graham’s shirt pockets.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: Twitter

They also found the insurance policy that Graham purchased at the airport on the day of the flight, which was hidden in a bedroom chest. Graham’s story was starting to unravel. At first, he admitted to causing the explosion at the restaurant and also to leaving his truck on the railroad tracks. At last, he admitted to the main question at hand…

His Confession

Finally, Graham broke and admitted to doing it all. Yes, he helped his mom pack her luggage and slipped a stick of dynamite inside. Then he confessed to causing the explosion of Flight 629. He described how he built a time bomb, with 25 sticks of dynamite, two electric primer caps, a timer, and a six-volt battery that he bought in Kremmling, Colorado.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

At the airport, he dropped off his wife, kids, and mother at the terminal door and drove over to a parking lot. He set the bomb’s timer to 90 minutes and took the luggage over to the United Airlines counter. The suitcase was 37 pounds overweight, for which King paid the $27 fee. The luggage was then loaded onto the plane.

No Federal Law for Blowing up a Commercial Airliner

While at the airport, he stopped by a vending machine and paid the $1.50 trip insurance policy for $37,500 in his mother’s name. He put his own name as the beneficiary. “Later on that evening, after my wife and I had returned home, we heard over the radio… that all passengers aboard had been killed.”

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

The FBI had investigated the bombing, but they handed the case over to Denver District Attorney Bert Keating. He charged Graham with state murder, which officials explained was a charge with “the more definite” law. You see, at the time, there was no specific federal law for blowing up a commercial airliner. Keating pushed for a quick trial.

First Case to be Televised

Due to a lack of laws regarding bombing commercial planes, Graham was only charged with killing his mother. Five months after the explosion, in April 1956, the case made its way to court, and the trial was the first in U.S. history to be televised. Graham’s attorneys argued that his confession to the FBI was made under pressure, but the judge dismissed their motion.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

Graham’s confession ultimately stood as evidence. Graham never testified, and none of the defense’s witnesses disproved the prosecutors’ evidence. On May 5, 1956, after the jury deliberated for 69 minutes, Graham was found guilty, and they recommended the death penalty. The judge agreed and sentenced Graham to death in August 1956. The execution was delayed at first but later affirmed by the Colorado Supreme Court.

His Last Words

Before stepping into the gas chamber on January 11, 1957, Graham’s last words were enough to send chills up anyone’s spine. The young murderer’s final words before his execution were: “As far as feeling remorse for these people, I don’t. I can’t help it. Everybody pays their way and takes their chances. That’s just the way it goes.”

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

A little over 14 months after the explosion, Graham was executed at the Colorado State Penitentiary. Before his death, during conversations with psychiatrists, they expressed their curiosity. They wanted to know: Why did he do it? Graham told the doctors that he was fully aware that there would be dozens of others on the plane. “But the number of people to be killed made no difference to me.”

The Aftermath

“It could have been a thousand. When their time comes, there is nothing they can do about it,” Graham coldly declared. The only good news in such an insane case was that the controversy surrounding the lack of suitable laws led to new laws being passed. New rules were made regarding attacks on commercial flights and other methods of domestic terrorism.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

In the years after the explosion, where farmers harvested the fields, there was a bare spot in the crops. It was where a body had fallen onto the ground. The alfalfa didn’t grow back. Small items were also found in the dirt; pens and eyeglasses. Two engines from the plane remained buried in the ground for several years, Conrad Hopp said.

The Land of the Dead

Hopp also said that when one of their cows died shortly after the blast, they found a chunk of metal inside of it. Hopp’s father, by no means a superstitious man, refused to water the fields at night on the east side of the farm for a long time after the explosion. Hopp’s brothers said they would hear voices.

Rocky Mountain News - newspaper clip about United Airlines Flight 629 investigation
Source: thedenverchannel.com

Hopp, himself, tries not to think about that night and its aftermath. “It’s something you put back in your mind. You just kind of want to forget about it.” Today, those rolling farmlands look the same as they did back in 1955. The land, Hopp believes, will likely become a subdivision one day. He only wonders if the people in their future homes will know what once landed in their backyards.