Many great air mysteries start as if everything is going normally. On November 8, 1957, Pan American Flight 7 took to the skies from San Francisco International Airport on its way to Honolulu, Hawaii carrying 36 passengers and 8 crew members. This was to be just the first leg of a much longer journey for the Boeing 377 Stratocruiser, also known by the nickname Romance of the Skies, as this was to be an around-the-world flight, stopping at a further 15 intermediate stops before eventually arriving in Philadelphia the following week. Pan American was the first airline to offer such around-the-world flights, and at the time it was a pretty exciting thing, a big deal, but this particular flight was not to complete its ambitious journey. In fact, it would never even reach Hawaii, and would fly into the domain of great unexplained aviation mysteries.
The flight went normally at first, taking off at 11:30 a.m. for an estimated 10-hour flight, and at 5:04 p.m., the captain made a routine position report at a position about 1,028 miles east of Hawaii and informed ground control that he would contact them again at 6 p.m. So far, so normal, and there was nothing ominous or worrying reported at this time, with an experienced crew and pilot making everything seem fine. 6 p.m. came and went with no further communication from the flight, and when nearly 2 hours passed with no word, the coast Guard was scrambled to mount a search with planes. Since there had been no distress call there wasn’t too much alarm at this point, but it was still highly unusual, and it was even stranger when no sign of the plane could be found, nor were there any replies to efforts to contact the plane. It was as if Flight 7 had just vanished into thin air. This is when people began to panic.
The disappearance of Flight 7 sparked one of the most massive sea searches in recent memory, the largest ever launched up to that point, mobilizing the Coast Guard and U.S. Navy and utilizing aircraft, submarines, and ships, including the U.S. Navy aircraft carrier USS Philippine Sea. The entire region of the plane’s last known position, covering a total of 150,000 square miles of the Pacific Ocean east of Hawaii, was scoured for days by a flotilla of ships and numerous aircraft before finally locating a 33-square-mile swath of scattered, floating debris, as well as 19 bodies, bobbing about around 1,000 miles northeast of Honolulu. The bodies and debris confirmed that this was where Flight 7 had gone down, but there were many strange clues and anomalies. For one, the plane was determined to have gone down more than 90 miles north of its intended flight plan, which was odd because there had been no message from Captain Gordon H. Brown to that effect and he was a seasoned pilot who had been with the airline for over a decade. The lack of any distress call was also seen as very odd, as many of the dead passengers had on life vests and none of them had shoes on, suggesting that they had some advanced warning before crashing. Why wasn’t there a distress call? No one knew. Also odd was that when autopsies were done, the bodies were found to have a higher than usual concentration of carbon monoxide
As the investigation into the crash began, there was a compelling possible lead when three pilots reported hearing faint radio distress signals from a hand-operated emergency radio of the type used on life rafts. A total of ten such broadcasts were heard over a period of 45 minutes, mostly unintelligible, but the words “four four” could be heard, which matched the last two numbers of the plan’s tail number. However, it was determined that there was no way to know if the transmissions had any connection to Flight 7, and they could have originated from the mainland. In the meantime, authorities were trying to figure out why the plane had gone down in the first place, which was proving to be a frustrating challenge. Some pieces of the debris showed signs of burn damage, but it was above the water line, none of the bodies had been burned, and it was found that the fire had likely happened post-crash. Another idea was that the plane might have run out of fuel, but if that were the case why had there been no distress call and why would the plane head away from its intended destination to run out of fuel in the first place? The plane had had more than enough fuel to make it to its destination, so what was going on aboard that plane? Unfortunately, no major components of the plane could be recovered, and so speculation was rampant. Had there been a mid-air explosion? Was the plane sabotaged? Had it been hijacked? No one had a clue and there simply wasn’t enough evidence to support any one idea.
One area that was looked into was why there had been elevated levels of carbon monoxide in the recovered bodies, as it was thought this could be an important piece of the puzzle. One idea was that it could have been due to gas leaking into the fuselage, perhaps through a leak caused by a failure of one of the engines. It could also have been caused by acetate film in the cargo hold releasing the carbon monoxide after being exposed to high heat. It could also have been maliciously pumped into the cabin to incapacitate those aboard or could even have been due to just the normal decomposition process of the bodies. In the end, the only thing that could be determined for sure was that none of the victims had died from the carbon monoxide. There was no solid proof to support any of these possibilities, and the presence of the carbon monoxide remained a mystery.
Another avenue of the investigation was that the crash could have been due to poor maintenance of the aircraft or some technical malfunction, as the Boeing 377 Stratocruiser did not have an exactly sterling record, but as the investigation continued they also looked more and more into the possibility of foul play. Authorities looked into any suspicious insurance policies that had been taken out before the flight or anything else that seemed off, and turned up some suspicious activity. One person of interest was a Eugene Crosthwaite, who had been a purser on the plane and apparently had held a grudge against the airline. Not only that, but just a few days before the flight he had changed his will and left a copy of it in his abandoned car at the airport. Another suspicious passenger was a former Navy underwater demolitions and explosives expert by the name of William Harrison Payne, who just before the flight had purchased three separate insurance policies, including a policy that paid double in the event of accidental death, and making it even more suspicious was that he had been heavily in debt, had bought only a one-way ticket to Hawaii, and his body was not among those found. He was also known for having had exceptional bomb-making skills, but in the end this led nowhere, as the Civil Aeronautics Board determined that there was no evidence at all that an explosion had brought the plane down. In fact, laboratory examination of the plane’s wreckage had ruled out the possibility of a bomb explosion of any kind. In the end, no one was ever actually arrested in connection with the crash, the leads dried up, and investigators were still as stumped as ever.
Other more radical theories were proposed during all of this. There was the idea that the plane had been hit by a meteor, and there was even talk of being shot down by or colliding with a UFO, but there was never any definitive answer. After years of multiple investigations and pursuing every clue and lead, the Civil Aeronautics Board came to the conclusion that there was just not enough information and recovered bodies or wreckage to adequately come to any solid conclusion as to why Flight 7 had vanished and then crashed, eventually stating, “The Board has insufficient tangible evidence at this time to determine the cause of the accident.” The final verdict was that all of their efforts to get to the bottom of the incident were inconclusive, and it has wallowed in the realm of uncertainty and debate ever since, managing to generate discussion and debate despite the fact that the official investigation is basically shelved. We are left to wonder just why this seemingly routine flight just sort of wandered off the face of the earth, with no distress signal or any warning whatsoever, just to turn up crashed in the middle of nowhere far from where it was scheduled to be. Why did this plane go down and why were the victims found found to have such high levels of carbon monoxide? Was this pilot error, a mechanical failure, foul play, or something else? We still don’t know, and Pan Am Flight 7 has gone down as one of the greatest aviation mysteries of recent times.