🔗 Share this article

At least nine people lost their lives and 11 others were hurt after a freight aircraft crashed while taking off from an international airport in Kentucky's largest city on Tuesday night.

Aviation experts believe the plane crashed after a single engine malfunctioned and another appeared to be damaged while lifting off.

It is unclear what caused the plane to crash, prompting a massive fireball to ignite after it failed to take-off from the airstrip. Video evidence revealed fire had already engulfed one wing of the aircraft during its takeoff attempt, which may have spread across the aircraft and caused the explosion, or the jet could have caught fire after colliding with an object on the ground.

What is apparent is that the 144,000 litres of fuel aboard the trijet aircraft needed for the flight likely escalated the blaze, which rapidly extended to several buildings beyond the runway and burned for hours.

How did it start?

UPS uses the Louisville air hub as a logistics center for its global operations and its Flight 2976 was beginning of a 4,300 mile trip to Honolulu in Hawaii when the cargo plane attempted to take off.

Tracking information from flight monitoring services shows the plane started moving along the designated runway at around 17:15 local time and attained a maximum velocity of 214mph.

However, confirmed videos demonstrate that when the plane reached this speed a blaze had fully consumed its port side and the aircraft failed to gain altitude before the enormous detonation.

Officials issued a shelter-in-place order to area inhabitants and scrambled numerous fire crews to the location.

Governor Andy Beshear confirmed details seen in CCTV footage that shows the aircraft flying just feet above the surface before a bright flash consumed the aircraft. It is then seen slamming into the ground as a massive fire explosion erupts around it about a minute into its journey.

Authenticated footage taken by motorists on a nearby highway showed the flames erupting into the skyline while subsequent recordings showed smoke billowing from the scene.

Aerial images shown on local media showed debris showering the runway and landing on the tops of multiple nearby establishments.

Potential causes of the accident

ATC transmissions reviewed are mostly unclear and full of interference so no meaningful conversation can be heard about the incident as it developed.

But analysts suggested that a catastrophic malfunction of two of the engines may have been the cause of the tragedy.

The MD-11 transport plane uses three powerplants. Two are installed under the airfoils, and a third is built into the tail at the bottom of the tail fin.

Video verified revealed a blaze engulfing the left wing of the aircraft, which then leaned leftward as it attempted to gain lift and become airborne.

Multiple specialists separately proposed the left engine may have detached from the plane following a technical or physical breakdown.

Additional photographs captured post-accident showed a burned powerplant sitting on the turf next to the runway.

An experienced former aviator and aircraft safety specialist commented that it was "almost unheard of" for an powerplant to separate in flight.

The expert recalled the 1979 aviation disaster disaster, in which 273 people were killed after the aircraft's powerplant separated as it took off from O'Hare International Airport. Parts of the engine had been damaged when it was installed on the aircraft, but the expert said it was too early to say whether a comparable issue led to the powerplant separation on the MD-11.

The expert explained the freight aircraft would have been capable of flight with only two powerplants but the damage caused by the wing blaze was likely so great it caused the plane's third engine to lose thrust.

"With such a catastrophic event we cannot determine what other damage was caused when the engine came adrift," the expert commented.

Another aviation expert said the footage seemed to indicate the remaining powerplant had been compromised because it released smoke. The issue could have happened while it was struck by wreckage from the blaze and the powerplant separation.

"The upper engine that expelled a puff of smoke appears to wind down right after," the expert stated. "That left only the starboard powerplant generating power, creating a severe power imbalance and making the plane incapable to gain height.

"Failing two powerplants while departing leaves the aircraft with only a third of its power and little chance of maintaining flight, especially at full departure mass," the expert added.

Why did the crash cause such damage?

Post-accident videos showed a scene of complete chaos with numerous blazes blazing across a extensive area of the site and smoke rising upward.

The aircraft, which was three decades old and had been used as a passenger plane until 2006, had previously made one round trip from Louisville to Baltimore in Maryland on Tuesday.

It has not been confirmed what cargo was aboard the flight bound for Hawaii, though officials said the aircraft didn't contain anything that would pose an increased danger of contamination.

"This involved extended freight transport from Kentucky to Hawaii, so the trijet was carrying a lot of jet fuel," an expert commented. "That heavy fuel load not only diminished capability but also accounts for the large fireball seen after the crash."

Authorities told reporters that the aircraft was transporting 144,000 litres of jet fuel for the long journey when it crashed. The fire was likely amplified on the ground because the plane crashed into a fuel processing facility next to the airport.

A specialist indicated investigators will now focus on how the initial fire began, and "whether debris struck the centre engine, and if previous repairs on the portside powerplant were a factor." He added: "Atmospheric conditions were favorable, so environmental factors are unlikely."

The federal investigation agency has dispatched personnel to the site and will take charge of the probe into the accident's origins, though this can take up to two years to finalize.