The Ghost Blimp Mystery and the 2 Navy Men Who Vanished
On the morning of August 16, 1942, a U.S. Navy blimp lifted off from Treasure Island in San Francisco Bay carrying 2 men on a routine wartime patrol.
Several hours later, the blimp came back but the men didn’t….
The unmanned airship drifted toward San Francisco, bounced off the ground and eventually crashed into a street in Daly City.
Its radio still worked and the parachutes were aboard, but there was zero evidence of fire or an enemy attack.
Lieutenant Ernest DeWitt Cody and Ensign Charles E. Adams had simply vanished.
Neither man was ever found.
Hunting Submarines Over California
America was less than a year into World War II, and fears of Japanese submarines operating off the West Coast were very real.
The Navy used blimps to patrol coastal waters because they could remain airborne for long periods and fly slowly enough to inspect suspicious activity below. 
L-8 was no ordinary advertising balloon and the former Goodyear airship had been acquired by the Navy and armed for anti-submarine patrols.
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Only months earlier, it had even delivered equipment to the USS Hornet before the carrier departed with the bombers used in the Doolittle Raid.
Cody was considered an accomplished airship pilot.
“one of the most capable pilots and one of the most able officers. He was cool and collected in emergencies, and I never knew him to become excited.”– Lieutenant Commander Donald Mackey
That makes the absence of a distress call particularly interesting.
Cody was not an inexperienced pilot likely to panic when something went wrong.
Adams was also an experienced Navy man who had received his commission only the previous day.
At 6:03 that morning, they departed Treasure Island aboard L-8.
Something in the Water
The patrol initially went according to plan.
At 7:38 a.m., L-8 reported its position about 4 miles east of the Farallon Islands.
Minutes later, another transmission arrived.
“Am investigating suspicious oil slick, stand by. Will call you back.”– L-8 radio transmission, August 16, 1942
An oil slick could indicate a submarine operating beneath the surface, so Cody and Adams descended for a closer look.
It was the last known radio message from either man.
The crews of the fishing vessel Daisy Gray and Liberty ship Albert Gallatin watched the blimp circle the area.
L-8 descended as low as roughly 30 feet above the water during the investigation, and witnesses could still see 2 men inside the gondola.
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For roughly an hour, the airship remained around the mysterious slick.
Shortly after 9 a.m., L-8 dropped ballast, climbed and headed back toward San Francisco.
The Blimp Comes Home Alone
Hours later, people along the California coast noticed something strange approaching from the Pacific.
It was L-8, and something was clearly wrong.
Witness Bruce McIntyre later described what he saw.
“It was dished on top and appeared to be drifting with its motors off. I could see no one in the cabin.”– Bruce McIntyre, eyewitness
The observation suggested L-8 was already empty before its final crash.
Whatever happened to Cody and Adams apparently occurred somewhere between the oil slick and the California coastline.
The sagging airship came down near Ocean Beach before becoming airborne again. 
After losing weight during the chaotic descent, it floated back into the sky and continued inland.
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What followed must have been one hell of a sight…
The crippled Navy blimp drifted across neighborhoods, scraped rooftops and tangled with telephone lines while residents watched from below.
Eventually it descended into Daly City and crashed across Bellevue Avenue.
People rushed toward the wreckage expecting to rescue the crew, but the gondola was empty.
An Empty Gondola
Firefighters initially wondered whether the men could somehow have become trapped inside the enormous fabric envelope.
Navy investigators searched the gondola for an explanation and found an aircraft that, despite its rough landing, offered remarkably few answers.
Again, the parachutes and rubber life raft both remained aboard. 
2 life jackets were missing, but crewmen were expected to wear them while operating over water, meaning Cody and Adams may already have been wearing them when they disappeared.
Contemporary reports also indicated that investigators found no catastrophic mechanical failure that could explain the mystery.
“The craft had been in perfect working order.”– United Press, August 18, 1942
If mechanical trouble had forced both men out, there was no obvious failure left behind to tell the tale.
Whatever happened apparently unfolded without either experienced officer managing to send a distress message.
The Search Comes Up Empty
The Navy launched a major search by land, sea and air.
No trace of either officer was discovered.
The mystery became news across the country, with photographs of the collapsed L-8 appearing in newspapers while investigators tried to determine how an operational Navy aircraft could return without its crew.
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One contemporary report summed up the growing confusion. 
“The mystery of the riderless Navy blimp deepened today as Navy authorities admitted they were without a clue.”– United Press, August 18, 1942
That wasn’t newspaper hype pulled from thin air. Investigators had the aircraft, witnesses and the crew’s final transmission, yet none revealed when or why the 2 men left the gondola.
No bodies washed ashore, no confirmed personal effects were ever found, and neither Cody nor Adams ever resurfaced.
Did One Man Fall Overboard?
The simplest explanation may also be the most haunting.
Perhaps one officer fell from the gondola while L-8 hovered close to the ocean investigating the oil slick.
The other may have tried to save him and fallen as well.
Such an accident could explain why both men vanished while the blimp continued flying.
Other theories soon filled the vacuum.
Some wondered whether the men had encountered a Japanese submarine.
Others suggested they might have voluntarily abandoned the aircraft for reasons now lost to history.
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As decades passed, increasingly exotic explanations appeared, including secret military experiments and alien abduction.
There’s no compelling evidence for those later theories and the documented mystery is strange enough without them.
The Ghost Blimp
L-8 survived the incident.
After World War II, it went back to Goodyear and eventually flew again under the name America.
James Riley Hill was originally supposed to be the third man aboard L-8 that morning.
Shortly before departure, Cody decided the blimp was carrying too much weight and ordered him off.
Hill later remembered Cody’s decision.
“It made sense to me. There was no reason for three of us to go.”– James Riley Hill
Cody and Adams were eventually declared dead, yet exactly how they disappeared remained unresolved.
References:
https://www.history.navy.mil/content/history/museums
https://navalaviationmuseum.org/l-8-control-car/
https://airandspace.si.edu/stories/editorial/special-delivery-doolittle-raiders
https://www.history.navy.mil/research/histories/ship-histories
https://www.sfchronicle.com/bayarea/article/Ghost-blimp-s-enduring-mystery