Moments before Pacific Southwest Flight 1771 crashes on a cattle ranch in California, gunshots are heard in the cabin.

The FBI and NTSB join forces to determine how terrorists hijacked American Airlines Flight 77 and flew it into the Pentagon on September 11, 2001.

A runway collision at a small airport turns tragic when passengers cannot escape the burning aircraft.

Investigators try to figure out why a private Learjet carrying golf legend Payne Stewart went rogue before crashing in a South Dakota hayfield.

An investigation of a charter plane that moves off course and goes down in Canada's far north.

When a cargo plane crashes at a U.S. airfield in Afghanistan, investigators reach a conclusion that ultimately proves incorrect.

When a plane carrying Russian tourists crashes in Egypt, investigators face political tensions and terrorist claims in their search for the truth.

A new investigation sheds light on the controversial 1961 plane crash that killed U.N. Secretary-General Dag Hammarskjöld.

When a commuter turboprop plane crashes at an Irish airport, investigators uncover a startling gap in aviation safety.

Atlantic Airways Flight 670 careened off the runway and became engulfed in flames.

A plane carrying Mexico's interior minister crashes into Mexico City's financial district.

When the crash of a commuter plane in Georgia killed a NASA astronaut, a four-term U.S. senator and 21 others, the disaster grabbed headlines around the world.

An Air France Concorde crashes into a Paris hotel after takeoff on July 25, 2000.

Almost immediately after taking off from Madrid International Airport, Spanair Flight 5022 banked to the right, slammed into a creek and burst into flames.

When John F. Kennedy Jr.'s Piper Saratoga crashed in 1999, the NTSB faces enormous pressure to find the wreckage and the cause.

TAM flight 402 slammed into a residential neighborhood and burst into flames, just seconds after lifting off from Congonhas airport in São Paulo, Brazil, killing all 95 people on board and three people on the ground.

Investigators try to find the cause of two similar air crashes that happened nearly 12 years apart.

When a commercial airliner goes down in eastern Ukraine in 2014, examiners must conduct an investigation in the middle of a war zone.

Some of history's worst air disasters.

Some of history's worst air disasters.

Some of history's worst air disasters.

Advanced computer graphics, forensic science, eyewitness accounts, interviews with experts, archival footage and re-enactments piece together in great detail the events that led to some of the biggest disasters of modern time.

"Dangerous Flights" goes inside the perilous business of aircraft delivery, following six pilots as they risk their lives to deliver small, used airplanes to destinations around the world. The business takes them from the frozen Siberian arctic to the Amazon rainforest, often through unpredictable situations and life-threatening weather conditions. Each episode features different "ferry-flying" missions, as the pilots battle co-workers, demanding customers and the elements in order to deliver the airplanes intact and on time.

"X-Ray Mega Airport" uses the latest technology to reveal the inner workings of Frankfurt Airport in Germany. The series employs computer-generated imagery to demonstrate what is underneath the surface of a plane, the internal space of a cargo-carrying truck, and even exposes what goes on in the minds of passengers and crew during a flight. The brain waves of a pilot are documented as he attempts to land an aircraft in crosswinds, and engineers are seen working on an Airbus A380's engine. Other episodes include the operations behind movement of luggage, how the conveyor belt system works and how controllers can single out pieces of luggage among thousands.

To soar through the skies is a dream. Modern technology has allowed human beings to take to the skies and while plane crashes are rare, there's still the issue of near misses. These technological advances are capturing these near misses on camera and cockpit recordings to provide insight as to the terror they can cause. See how pilot errors, technical failures, massive storms and small mistakes can place passengers into life or death situations and the why of these incidents and how to prevent them from reoccurring.

Taking to the sky in an airplane can be dangerous when the weather doesn't cooperate. This documentary series investigates aviation accidents and how the elements contributed to them. Interviews with witnesses and survivors, testimony by experts, and data from the plane's black box aid in exploring each incident. The FAA's case files are used to create animations to diagram what happened before each crash. Fog, haze and hail are some of the weather conditions responsible for the disasters.

You might say the Tweto family business has taken off, despite the sometimes unforgiving conditions in which it operates. The Twetos -- dad Jim, mom Ferno, and daughters Ariel and Ayla -- run Era Alaska, an airline that transports life's necessities to the isolated rural inhabitants of the Bering Sea coastline. Whether it's carrying sled dogs bound for the Iditarod race, medicine for sick children or food supplies to miners working on the North Slope, the Era Alaska crew serves as a lifeline for many of the state's residents.

The life of an Alaskan bush pilot is never dull.

This documentary series focuses on extreme construction projects -- be they the biggest, tallest, longest or deepest in the world -- and the machines used to create extraordinary structures. Episodes include the people responsible for the cutting-edge design and engineering of each build, talking about how concept transformed to reality. The processes that go into staffing and operating the modern marvels once they are completed are also covered.

A look behind the scenes at how everyday things are manufactured. Typically each episode includes three to four products featured, with a mix consisting of common items such as jeans, aluminum foil and cereal, and less predictable ones like wax figurines, braille typewriters and pinball machines.