In episode 107 of Take to the Sky: the Air Disaster Podcast, we cover the shocking story of the crash of Ethiopian Airlines Flight 409, which crashed into the Mediterranean Sea on January 25, 2010, near Beirut, Lebanon, killing all 90 people onboard. Shortly after a normal takeoff, and during just four minutes and seventeen seconds of flight, the pilots of Flight 409 demonstrate delayed reactions, incorrect or exaggerated inputs, and erratic decisions, until eventually they inadvertently flew their plane into the sea. Early reports and rumors blamed a potential onboard explosion caused by a bomb. But soon, the Lebanese Civil Aviation Authority (LCAA) rules out a terrorist’s bomb, along with either a mechanical or maintenance issue, or the performance of the aircraft, leaving one remaining possibility: pilot performance. Ultimately, the LCAA attributes the crash of Flight 409 to “subtle incapacitation,” which happened once the crew lost situational awareness, causing them to make a series of inputs that led to the loss of control of the airplane. Despite the probable cause conclusions, it is difficult for the LCAA to definitively pinpoint why the captain became subtly incapacitated, which may have been caused by a number of factors, including, fatigue, stress, feelings of overwhelm, task saturation, and external factors, such as it being a nighttime flight and raining. However, representatives from Ethiopian Airlines fervently disagreed with the LCAA’s findings, held fast to the belief that a bomb caused the plane to crash, and published a scathing 10-page rebuttal, which many experts in the aviation community regarded as full of unsubstantiated claims. These differing perspectives were never reconciled. Consequently, the crash of Flight 409 remains one of the most confusing and controversial air disasters in recent history. 

Ethiopian Airlines Flight 409 Takes off Normally from Beirut with 90 People Onbaord

Just after midnight on January 25, 2010, the crew of Ethiopian Airlines Flight 409 is preparing for its scheduled departure from Rafic Hariri International Airport in Beirut, Lebanon, for Addis Ababa, Ethiopia. Outside the plane are scattered thunderstorms, and visibility is low, even for a nighttime flight. Nevertheless, the crew continues its preparations for takeoff as it normally would, including all the preflight checklists and briefings. Onboard Flight 409 are 8 crew, including the captain and first officer, and 6 cabin crew members. Joining them will be 82 passengers. An interesting note about one of the passengers – one of them is an onboard security officer. Remember, for a period after the September 11th attacks in 2001, flights would often have an undercover security officer onboard as an added layer of protection against possible takeovers of the aircraft. 

The captain is 44-year-old Habtamu Benti Negasa, who has been with Ethiopian Airlines since 1989. He is one of the airline's most experienced pilots having logged over 10,000 flight hours, including almost 2500 hours on the Boeing 737, which is what they are flying today. The first officer is 23-year-old Aluna Tamerat Beyene. He is more junior in his experience, having been with the airline for just a year and having just 673 flight hours under his belt, with about half those hours on the Boeing 737.

ATC Gives Flight 409 a New Heading Shortly After Takeoff

Tonight, Flight 409 will takeoff from Beirut in the direction of the Mediterranean Sea and away from the steep mountains that surrounded the airport. First, they will head southwest before making a U-turn towards a navigational checkpoint known as Chekka. 

Finally, the intermittently stormy weather seems to have let up, and it is now time for Flight 409 to take to the sky. Air traffic control (or ATC) also gives the flight crew new instructions for their directional heading after takeoff: instead of making a U-turn, they will takeoff and make an immediate right turn toward Chekka. 

And so, around 2:30 AM local time, Flight 409 takes off into the cloudy, rainy night sky. Everything at this point is, as one investigator would later remark, “routine, ordinary, and well-executed.”

Air traffic control then instructs the flight to climb to 29,000 feet (or 8800 m). The flight crew continues to fly on the previously given directional heading 3-1-5. Just a quick note about the navigational headings we’ll be talking about in this story: a directional heading is typically based on compass directions, so 0° (or 360°) indicates a direction toward true North, 90° indicates a direction toward true East, 180° is true South, and 270° is true West. Every heading is numbered based on the precise direction by degrees that the plane should travel.

But soon after they are airborne and sailing through 2,000 feet (or 600 m), the scattered storms that were, just a few moments before, dissipating, now seem to be in their direct path. ATC has also noticed the weather on their radar display and advises the flight crew that if they want to avoid the storm, they should change headings from 3-1-5 to 2-7-0. 

Ethiopian Airlines Flight 409 Banks Dangerously to the Right, Overshooting the Directional Heading

But before the flight crew can confirm this heading change, suddenly, a warning chime sounds loudly in the cockpit – the computerized voice begins to chant, “bank angle! bank angle!” This is a warning that tells the pilots the right turn they are making is becoming dangerously steep and may risk causing a stall or an upset to the plane. To correct this potentially urgent situation, Captain Negasa turns the plane to the left, away from the right and away from the direction of the storms. But his control column input is a sharp left wheel input of approximately 40 degrees – he’s gone too far in the opposite direction. It causes the plane to begin rolling again, this time to the left and all the way to 45 degrees and then beyond – to 64 degrees. This action also means that the flight crew have overshot their heading and now could be in the path of other aircraft. Concerned, ATC jumps into action and instructs Flight 409 to fly on the new heading 2-7-0 and turn right (as their instruction had been to do) and away from Beirut and its busy airspace and the mountainous terrain. 

However, inside the cockpit, things are reaching a level of chaos. Captain Negasa does not understand what is happening with his controls – the continuous bank angle warnings tell him the plane may be on its way to stalling. To try and avert a stall, he goes in for maximum power. When he does, the plane pitches up steeply. Due to the steep climb and excessive bank angle, the plane begins to dangerously decelerate. The pilots will need to step in and rectify the situation, or else, the wings could lose lift and the plane may stall. And, almost predictably, the stick shaker stall warning activates, filling the cockpit with a deafening rattle.

Inside the cabin, passengers are being tossed around in their seats, first by the rolling motion of the first right turn and then by the rolling motion of the left turn. Overhead bins would pop open, luggage falling out and around the cabin. But this was nothing compared to what was about to come next. 

Ethiopian Airlines 409 Enters into First Stall, then Races Upward into Steep Ascent

Moments later, the airplane does exactly what the bank angles warning cautioned against: the plane stalled as it reached 7,700 feet (or 2300 m), and then it began to descend. The stick shakers continued to rattle, all while the plane’s airspeed dropped to a mere 118 knots (or 135 mph), and the bank angle reached 68 degrees left. As the plane entered the stall, the nose fell through, sending the 737 diving nose-first toward the sea. 

At what would have been an understandably terrifying moment, passengers are pushed violently into their seats, the weight of 3Gs pressing on their bodies as the plane dives downward. They would have felt like rocks being hurtled toward the ground, being pulled down by the strength of intense gravity. 

The plane, now gaining momentum from the dive, begins to rapidly gain airspeed, which makes the stick shaker stop. Hopelessly confused, Captain Negasa fumbles with the controls, turning the controls hard left while pushing the rudder to the right, a move that causes the two inputs to cancel each other out. At 6,000 feet (or 1800 m) the plane pulls out of the dive, but not because of pilot inputs. It is because of the high airspeed from the dive and the plane’s nose-high stabilizer setting– and when it does, the plane races upward into a second, even steeper ascent. 

Now the plane rolls hard left and the bank angle warning blares again. Captain Negasa shouts to his first officer, “Hold this thing!” 

Now in a steep climb, their airspeed inevitably begins to drop once more, and the stick shaker activates again, warning of another stall. Captain Negasa inexplicably keeps trying to roll left, turning the plane practically on its side. Banked ninety degrees to the left, the plane stalls a second time. The wings are unable to maintain lift, and the nose once again falls through, sending the plane into another, even steeper dive. At this point, passengers have survived one dive, only to be thrown into an intense upward climb, and then back again into this second steep downward dive. But it only gets worse next. 

Flight 409 Spiral Dives Toward Mediterranean Sea After Stalling Twice

From a maximum height of 9,000 feet (or 2700 m), flight 409 is now spiral diving toward the dark, stormy waters below, completely inverted. Inside the cabin, passengers would no doubt ne terrified, unable to move due to the enormous pressure of the spiral dive but knowing nonetheless that it would have to end eventually. Maybe some of them hoped for the end while others still clung to the hope that the pilots could pull them out of the dive and save everyone onboard. 

Captain Negasa cries out in terror as he furiously tries to control the aircraft, but his inputs only make the plane roll and pitch erratically. The 737, once an aerodynamic masterpiece, is being steered into somersaults and cartwheels through the air, until it rolls right side up, the bank angle fluctuating between 35 and 75 degrees left, until the dive grows even steeper. The airspeed reaches 407 knots (or 468 mph), subjecting the humans still clinging to life inside the aircraft to an unimaginable 4+ G’s, way beyond the structural limits of the aircraft. There was no end to the constant death-defying acrobatics that the aircraft was put through. That is, until the end came at last. 

Ethiopian Airlines 409 Slams into Sea at High Rate of Speed, Killing all 90 Onboard

At a height of 1,300 feet (or almost 400 m), the flight data recorder stopped recording under the enormous G-forces. Less than two seconds later, traveling at an immense speed, and only less than 5 minutes after it took off, Ethiopian Airlines flight 409 plowed directly into the waters of the Mediterranean, obliterating the aircraft and instantly killing all 90 people on board, including a three-year child and a four-year-old child. No one onboard ever had a chance of surviving this kind of impact. 

The nightmare experienced by passengers onboard Flight 409 could not be comprehended. But their bodies held the physical evidence that conveyed the hell they had been put through. The medical examiners stated they died from “the consequence of a violent trauma, with projection of the passengers against a hard surface (this being the water’s surface), resulting in severe vital lesions that led to immediate death before drowning. Most passengers suffered even more severe physical consequences that did not allow any autopsy to be carried out.” This included the bodies of the two pilots, which were only recovered in pieces. The only small measure of goodness related to the condition of the bodies was that DNA science was robust enough in 2010 to ensure that all passengers and crew were identified. And by the end of February that same year, they were. 

Lebanon Shocked by Ethiopian Airlines Flight 409 Disaster while Early Witness Accounts Claim Plane Exploded Before Crash

When ATC is unable to call up the flight crew of flight 409, they notify Lebanese emergency services, and the search for the missing aircraft commences by sea and by air. Meanwhile, the Lebanese Civil Aviation Authority (or LCAA) is tasked with investigating the accident, with the assistance of the BEA, Boeing, and the National Transportation Safety Board (or NTSB) of the United States.

While investigative efforts got underway, Lebanese Prime Minister Saad Hariri announced a day of mourning for the victims of the crash, ordering all government departments to close. Lebanese President Michel Suleiman, said the disaster was a major loss, not only for the victims' families but also for the nation, noting that the passengers included "a group of young men and women who left Lebanon to work abroad and to earn a living and raise the banner of their homeland."

The crash of Flight 409 is the worst aviation disaster to happen in Lebanon in the 35 years prior. The rarity of a crash like this meant rumors would abound that the only reason a commercial jetliner had fallen into the sea was if a terrorist’s bomb had put it there. And witness statements from people claiming to have seen the plane in its final moments legitimized these concerns when people say they saw the plane engulfed in a fireball right before slamming into the water. 

Ethiopian Airlines 409 Wreckage Proves Plane Hit Water Intact, Pitting Investigators Against Ethiopian Airlines

Amazingly, despite storms that thrashed the seas the day of the crash, on the morning following the crash, the airplane wreckage was in a debris field about 300 meters long and 100 meters wide (or 984 feet long by 328 feet wide) and at a sea depth of 45 meters (or 147 feet). Over the next almost four weeks, about 8% of the airplane is recovered and brought to the surface, but it is too expensive the raise the entire site. Investigators focus on raising key pieces of the aircraft, including several large pieces, such as the tail section and both the horizontal and vertical stabilizers and aft fuselage section extending forward to the #2 left entry door. Many more pieces of floating wreckage were recovered from the water’s surface near to the last recorded position of the airplane and near the beach of Beirut, about 8 miles NE of the impact site. Most importantly, the black boxes (the flight data recorder and the cockpit voice recorder) are eventually recovered. 

What is most telling for investigators when they view the debris field via underwater cameras is that the debris has formed a linear pattern, which indicates that the plane hit the water intact and only disintegrated on impact. There is also zero evidence of burn marks on any of the airplane parts, including those brought to the surface and those still on the seabed. Investigators chalk up witness statements about seeing the plane engulfed in a fireball as the effects of lightning coming from that stormy early morning of the crash. Obviously, this discovery should have put to rest rumors that a bomb or an inflight explosion was not the cause of the fatal flight; however, many in the public found it hard to believe otherwise. And in fact, it even caused a rift between representatives from Ethiopian Airlines, who felt early on the crash was caused by a bomb, and Lebanese and American investigators, who did not think a bomb was very likely. We will come back to this later. 

LCAA Investigation of Ethiopian Airlines Flight 409 Focuses on Pilot Performance as Cause of Crash

Investigators can also rule out anything mechanical that was wrong with the plane that could have caused this sequence of uncontrolled movements. And nothing in the plane’s maintenance records would point to a fatal issue or flaw. 

Investigators use the data from both black boxes to paint a picture of what happened in the five minutes leading up to the crash of Flight 409. Shortly after takeoff, the flight crew was instructed to turn right and maintain heading 3-1-5, but the plane goes in a different direction, which causes the plane to overshoot its heading. Then, ATC gives them a new heading of 2-7-0 so they could avoid the storms in their path. And when the flight crew made this turn, they again turned too far and banked too steeply. 

The problem faced by the LCAA was that it was, frankly, easier to rule out than to rule IN a cause that could explain what did happen. After eliminating all the possibilities of a bomb, inflight breakup, mechanical or maintenance issue, and operational performance of the aircraft, investigators are left with a final, yet complex and dreaded possibility: the performance of the pilots. 

Investigators cannot ignore the data before them. Over four minutes and seventeen seconds of flight, the pilots of Ethiopian Airlines flight 409 seemed to become more and more confused, their inputs becoming increasingly erratic, until eventually they flew their plane into the sea.

Even before takeoff, the pilots were going to battle a heavy workload in the cockpit. The very first mistake, though minor and not fatal, was that the setting for the horizontal stabilizer was set a little lower than normal for takeoff. This would have made the control column heavier than normal, though the airplane was still flyable, as investigators confirmed via a flight simulator. But it shows that perhaps the flight crew was not paying attention the way they should have been. 

Ethiopian Airlines 409 Pilots Demonstrated Poor Crew Resource Management 

Next, the black boxes show that as the plane took off, the first officer was very quiet, hardly responding to his captain’s requests, and at times, not following them, such as when the captain asked the first officer to engage the autopilot after takeoff. But the autopilot was never engaged, either because First Officer Beyene didn’t hear the captain, or because he attempted to do so but failed to engage the autopilot because Captain Negasa was still applying pressure to the control column, which would have prevented the system from activating. In either case, the failure to engage the autopilot should have led to further communication – the first officer should have let the captain know the control column pressure would not allow the autopilot to become activated. And, had the first officer done so, and autopilot been engaged, it likely would have prevented the crash from ever happening. And this dynamic happens repeatedly in the cockpit.

Not only did the first officer not engage the autopilot, but he also neglected to call out most of the captain’s mistakes, such as the steep bank angles, and did not respond when Captain Negasa became overwhelmed and asked for help.

LCAA Attributes Ethiopian Airlines Flight 409 Disaster to Captain’s Subtle Incapacitation

This leads investigators to attribute the disaster of Flight 409 to something known as “subtle incapacitation.” A pilot who is subtly incapacitated appears physically healthy and awake but has nonetheless lost the ability to make rational decisions. The big picture is that pilots who are subtly incapacitated lose situational awareness. This happens when a pilot is fatigued, stressed, experiences physical discomfort or task saturation. These factors may result in symptoms such as loss of judgment, failure to react to stimuli, illogical decision-making, and irrational control inputs. 

All these symptoms were apparent in Captain Negasa’s performance during the final minutes of flight 409. During the initial climb, his inputs were normal; once he started to lose situational awareness, his inputs became exaggerated or delayed; and then, following the first stall, his inputs were disconnected from the logical choices a pilot would make under normal circumstances. Investigators uncover that the captain worked almost nonstop for the preceding two months, which they believe made him more susceptible to subtle incapacitation. 

And investigators believe that the first officer never stepped in to call out the captain’s error because the captain was far more experienced, and the first officer had been taught that it was wrong to criticize a captain or to intervene. In fact, the first officer had been admonished during pilot training to stop asking so many questions of the captain of that flight because the airline claimed it “interfered with the flight.” 

As we can imagine then, when there is no single egregious error, but a combination of missteps that ultimately culminate in a loss of control, it can be hard to definitely say WHY these things happened during Flight 409. The LCAA tried to explain it when they said, “It is difficult to understand the captain’s logic to make all these input changes. He may have had difficulties to read the PFD as very unusual high banks and low pitch were encountered. He could have also felt some unusual heavy G loads which could have disoriented him. Those changes in flight control inputs and maintaining the thrust at go-around didn’t allow the captain to recover from stall situation or from the pitch down attitude but indicates that he was still struggling to save the situation. They surely indicate a high level of stress the crew was facing and a loss of situational awareness of what was really happening, apart from their awareness that they were facing an abnormal situation.”

This next explanation of what it means to become subtly incapacitated comes from the blog by Admiral Cloudberg, who explains the dynamics of the cockpit: “A pilot should at all times remain mentally ahead of their airplane, anticipating its movements well in advance. An old airman’s saying goes, “don’t let your plane take you someplace your brain hasn’t been five minutes before.” Whenever he focused on the plane’s pitch, the bank angle would go out of bounds, and vice versa. Unaware of what was going on behind the scenes, it seemed to him that some new problem presented itself every time he glanced at his instruments. It only took about a minute of flight under such conditions before he started to show symptoms similar to a mild panic attack.”

Ethiopian Airlines Representatives Publish Scathing Rebuttal to LCAA Investigation into Ethiopian Airlines 409 Crash

In the LCAA’s final report, investigators blamed the crash on the captain’s subtle incapacitation and the crew’s loss of situational awareness, which caused them to make a series of inputs that led to the loss of control of the airplane. Representatives from the Ethiopian side spoke out strongly against the report’s findings, and in response, published a strongly worded 10-page rebuttal. The Ethiopian rebuttal claimed that the LCAA and its investigators were “biased, lacking evidence, and incomplete,” and directly accused Lebanese officials of focusing on pilot error from the start of the investigation and ignoring contradictory evidence along the way. But, to many experts in aviation, the rebuttal makes several unsubstantiated claims, including that the plane’s movements were not commanded by the pilots; that the pilots made no mistakes; and that the captain could not have been subtly incapacitated because he continued to make active control inputs, never mind that those inputs were nonsensical and contradictory. 

Many in aviation consider the crash of Ethiopian Airlines flight 409 to be one of the most bizarre accidents to have happened in the last decade plus. Even after a full investigation that included rigorous analysis, it is difficult to put a finger on just precisely how events spiraled, literally, so out of control and so quickly. But perhaps all that is missing the point. As investigators have said on record about this crash, no amount of engineering can override subtle incapacitation, and that is perhaps the most chilling conclusion an air accident investigation can reach. And even if the investigation had pointed to more definitive and concrete conclusions, we’d end up in the same place anyway: with 90 people who spent almost 5 minutes in a proverbial hell on earth before losing their lives at sea in the dark of night, in a harsh, violent, and terrifying way. 

And THAT is the confounding and tragic story of the crash of Ethiopian Airlines Flight 409.