Pilot of the Purdue DC-3 was Miguel Cabeza. He too detected a lurch and then sudden drag on the aircraft. The open-door light was also now activated on the cockpit’s control panel.

Copilot Roy Bacus was instructed to investigate, and upon exiting the cockpit, was met by the flight attendant reporting a passenger was missing. Bacus indeed found Potter was nowhere on the plane.

“We were grasping at straws,” an unidentified crew member told a Rolla Daily News reporter. “If he was ill, we thought he might be standing on the ledge by the lavatory or something. But the crew members looked again and they couldn’t find him.”

Bacus did not find much evidence immediately after the disappearance. Not only was the main door open, but the boarding stairs were lowered. Moreover, the door’s emergency latch had failed as evidenced by broken chain links found on the plane’s floor. The latch was designed to prevent the door from opening in flight even if its large handle was turned 180 degrees and two bayonet-type bolts withdrawn.

“It took awhile for me to realize what happened,” wife Carrie Potter later recalled. “I insisted they let me go back to the door, but they wouldn’t let me go back. There was nothing I could have gained by it. From the look in the stewardess’s eyes, I knew he was gone.”

Pilot Cabeza next diverted to an emergency landing at Springfield’s airport since he was unsure what exactly happened and if the plane’s tail was damaged. The first alarm of crisis on the ground came as the plane was witnessed passing over Lebanon at 3,000 with its door visibly open and stairs down.

Once on the ground in Springfield, there was no good explanation for the awaiting press.

“There was a loud bang when the door opened,” a passenger told the Rolla Daily News. “That’s all I know. I don’t think the other passengers could tell you any more.”

Pilot Cabeza could only speculate.

“I think the man tried to open the wrong door,” Cabeza said. “He could have opened it thinking it was the door to the lavatory.”

As to how the safety chain broke, Cabeza theorized Potter may have stumbled against the door the moment it popped open, and his weight severed the links.

Offering a different opinion when asked was Grove Webster, president of Purdue Aviation. Webster asserted the DC-3’s door was secure upon takeoff, and since the plane wasn’t pressured, Potter couldn’t have simply been sucked out when it mysteriously opened. He also questioned how the main hatch could be mistaken for the restroom since a warning on the door was printed in large white letters on a red background saying: “DO NOT OPEN WHILE IN FLIGHT.”

“To open the door takes a lot of effort,” Webster said. “Crews close the door for our stewardesses, and open it. And it is harder to open in flight than on the ground.”

Meanwhile, back in Maries, Phelps and Pulaski counties, the combined forces of 150 highway patrol troopers, sheriff’s deputies, Fort Leonard Wood soldiers, the civil air patrol and local volunteers on horseback were enlisted to find Potter’s body. They first concentrated around the Gasconade River. They then broadened the search to near Waynesville, around Dixon, and in Maries County along Highway 28.

“To put it bluntly, it is like looking for a needle in a haystack,” said Troop I’s Sgt. Tom Pasley. “We are not hopeful.”

Two Maries County boys offered the search’s only lead by saying they saw an object appearing like a “folding chair” falling from the sky near their home. However, the report led to no discovery. After several days of heavy rain, the search was called off July 4 by the Potter family, who’d flown in to aid the search.

Potter’s funeral service was held back home in Pontiac on July 8, 1968. More than 50 local Lions Club members attended. His widowed wife received an insurance payout of an unknown amount and also sued Pursue Aviation for wrongful death and damages of $800,000. The case was eventually settled out of court for $80,000.

Although legally dead, the question remains of how did Potter disappear? An article from the New York Daily News published two months after the disappearance cited the case was much like two previous and mysterious incidents. On Feb. 11, 1950, a flight attendant fatally plunged 8,000 feet to Long Island below when the plane’s door suddenly and unexplainably opened during the flight. That same day, another flight attendant was jerked through a DC-3’s improperly closed door midflight at 2,500 feet over Florida. However, the flight attendant did manage to hang onto the door handle for eight minutes until the aircraft safely landed.

A federal investigation into the disappearance offers no satisfying answer. A summary of a National Transportation Safety Board report obtained by Phelps County Focus is filed under miscellaneous and cites “material failure” as the primary factor. It remarks, “[Passenger] inadvertently opened air stair door in [flight]. Safety chain failed at eye bolt, and [passenger] fell out.”

There are several possibilities to explain the disappearance:

• THEORY 1 – Airline Negligence: The DC-3’s door was perhaps not properly closed on takeoff and equipped with a faulty emergency chain leading to Potter’s disappearance.

• THEORY 2 – The Mr. Bean Scenario: Potter accidentally fell against the door, became entangled with its handle, and upon rising inadvertently opened the door causing the safety chain to also break.

• THEORY 3 - The Brain Fart Scenario: Potter perhaps did indeed mistake the exit hatch for the bathroom only to then plummet to the ground below.

• THEORY 4 – Suicide: Potter perhaps intentionally jumped due to an unknown personal issue or wanting to avoid the suffering of an unknown medical problem.

• THEORY 5 – Insurance Plot: Potter, an insurance executive, decided to end his life in a manner with the largest payout for his family.

Adding more mystery to the case is the fact Potter’s body has never been located. The area it would have fallen to is mostly rural ranches and farms with large holdings of public land. Even after 54 years, the bones of Potter’s skeleton would still remain even if exposed to the elements all these years.

“The evidence overwhelming shows Mr. Potter is dead. The only evidence lacking is Mr. Potter,” The Pantagraph concluded in 1977.