On a quiet September morning in West London this year, a man fell from the sky.

Today, on Dec. 10, police still don't much about him, including his name.

The story goes like this: the Associated Press said residents first discovered the man's crumpled remains on a city sidewalk. Detectives arrived and thought he'd been murdered, so they cordoned off the area.

The pieces just didn't match up though. The man had no papers, only Angolan currency, and was placed in a revealing location. The location was the key. The man's corpse was lying directly in the Heathrow flight path.

Police pushed that lead and found out that a plane landed at Heathrow from Angola right around the time medical authorities approximate the man's death.

Their new theory: the man was a stowaway, thrown from the ground when the plane released its landing gear upon its descent to the airport.

Authorities don't think the fall killed him though. According to aviation specialist Chris Yates of Yates Consulting, the man, starved for oxygen in an unpressurized part of the plane's undertow, most likely lost consciousness and died within the first hour of the flight.

"They so often end in fatality because more often than not stowaways climb into the wheel base or cargo hold, and those areas are not necessarily pressurized," Yates told the AP. "When you start moving beyond 10,000 feet, oxygen starvation becomes a reality. As you climb up to altitude, the issue becomes cold as well, the temperature drops to minus 40 or minus 50 degrees centigrade, so survival rates drop."

Stowaways have become increasingly common in recent years, many of whom make their way to Western Europe riding in a plane's undercarriage. Poor airport perimeter security in countries -- including Luanda, Angola -- makes it easy for non-ticketed passengers to clandestinely slide underneath planes.

While West London police claim to have no evidence of other stowaway deaths, residents say similar incidents have happened near Heathrow before.

"People say the same thing happened a few years ago a few blocks away"  Jay Sivapalan, 29, who works at the Variety Box convenience store half a block from where the body landed, told the AP. "We are near Heathrow and when they lower the landing gear, the body falls out."

In identifying the man, all West London law enforcement have to work with is a composite image of his face and a photo of a tattoo on his arm, with the letters "Z" and "G" slashed by a horizontal line. While authorities suspect he is Angolan, there is only circumstantial evidence linking him to the country. Police have not been able to work successfully  with Angolan authorities.

The man who fell from the sky is believed to be an African man between the ages of 20 and 30. He was wearing white sneakers, jeans, and a gray sweatshirt when he was found on the street. 

"It was a beautiful blue day, really sunny, but we had to keep the children inside," Catherine Lambert, who lives a few doors down from where the man's body was found, told the AP.  "I didn't want the children to see, and to have to explain to them and put fear into them every time a plane goes over."