On the 24th of June 1975, the crew of an Eastern Airlines Boeing 727 lined up to land on runway 22L at New York’s John F. Kennedy International Airport. Ahead of them, two other planes flew through a thunderstorm just off the end of the runway, encountering violent winds that nearly sent both aircraft plummeting into the ground. But Eastern Airlines flight 66 continued blithely after them, unaware of the true danger of the storm that lay ahead. Just moments from landing, a powerful downdraft gripped the 727 and slammed it to earth, where it struck the approach lighting system and slid in pieces onto Rockaway Boulevard. Of the 124 people on board, only 11 survived. The crash revealed fatal shortcomings in the way everyone in the industry understood and communicated about severe weather. And in a seminal report that laid the foundations for numerous future safety improvements, the National Transportation Safety Board revealed how the near total absence of a system for dealing with the problem of wind shear led to the loss of 113 lives on a stormy afternoon in New York City.
Like many summer days in the New York area, the 24th of June, 1975 held the promise of a blustery afternoon. For pilots flying into the region’s three major commercial airports, afternoon thunderstorms were a fact of life. So it was not with great trepidation that the crew of Eastern Airlines flight 66, a regularly scheduled service from New Orleans to New York City, read out the weather report prior to departure: the prediction was for “widely scattered thunderstorms” with “possible light rain after 20:00.” All would be fine, they thought; they were scheduled to arrive around 16:00, well before the worst of the weather.
In command of flight 66 that afternoon were Captain John Kleven and First Officer William Eberhart, who had a combined 23,000 flight hours. Assisting them would be Flight Engineer Gary Geurin, who was undergoing a line check under the supervision of senior Flight Engineer Peter McCullough. Also on board were four flight attendants and 116 passengers, including 19 Norwegian navy personnel, a prominent banker, and the Episcopal bishop of Louisiana.
Most of the flight from New Orleans proved to be uneventful, until the plane neared John F. Kennedy International Airport. The thunderstorms came earlier and turned out to be stronger than advertised, and as the cells started to build up all over the New York Terminal Control Area, delays began to mount. Controllers at Kennedy Airport started putting numerous aircraft, including Eastern Airlines flight 66, into holding patterns over the Southgate and Bohemia intersections.
As they held over Southgate, the crew of flight 66 discussed their options for landing. Because the storms had not been forecast to affect their arrival, they had taken only the minimum required fuel, and if they had to hold for long their options would be severely limited. To make matters worse, their designated alternate airport — LaGuardia — was also affected by the thunderstorms. “One more hour and we’d come down whether we wanted to or not,” one of the crewmembers quipped.
Ahead of them, one plane after another turned in to land on runway 22 Left at Kennedy. Among them was Flying Tiger Line flight 161, a Douglas DC-8, which found itself on final approach at about 15:55. As it neared the runway, it flew underneath a developing thunderstorm, where it encountered a stiff headwind. But at a height of 300 feet above the ground, the headwind suddenly disappeared, and the airplane’s speed fell by 17 knots in 10 seconds. At the same time, a downdraft slammed it from above, and their rate of descent more than doubled from 750 feet per minute to 1,650. The plane started to descend below the glide slope, the ground rising up from below with astonishing rapidity. The captain jammed the throttles forward to takeoff power, but to his amazement, the plane not only didn’t climb, it barely even managed to level off. He wanted to abandon the approach, but even with maximum thrust he couldn’t get his aircraft to climb, so he had no choice but to push through to landing. Seconds later the DC-8 touched down hard on the runway, its crew shaken but unharmed. The cattle being carried in the cargo hold, however, were not so lucky — according to an interview by the pilot years later, they all broke their legs and had to be put down.
Convinced that he had just narrowly avoided a disaster, the captain of the DC-8 called the controller and said, “I just highly recommend that you change the runways and… land northwest, you have tremendous wind shear down near the ground on final.”
The controller looked at the reading from the single anemometer measuring wind speed for both runways 22R and 22L. “Okay, we’re indicating wind right down the runway at 15 knots when you landed,” he said to the DC-8 captain, implying that runway 22L had a manageable headwind that should have been no problem at all.
The captain was not one to be told what he did and did not experience. “I don’t care what you’re indicating,” he snapped back, “I’m just telling you that there’s such a wind shear on the final on that runway that you should change it to the northwest.”
But the controller never replied. And behind them, more planes kept coming in to land on runway 22L.
The next in line was Eastern Airlines flight 902, a wide body Lockheed L-1011 Tristar. At 15:57, flight 902 flew into the same thunderstorm transited by Flying Tiger Line flight 161 two minutes earlier, this time at an even lower altitude. Driving rain suddenly lashed the jet, and they started veering to the right of the runway heading. Then the wind changed direction so rapidly that they lost 24 knots of airspeed in ten seconds and their descent rate increased from 750 feet per minute to 1,215. The plane dropped precipitously, and just like the captain of the DC-8 before him, the captain of the L-1011 pushed the throttles forward to go-around power to abandon the approach. Straining against the incredible downdraft, the L-1011’s three engines just barely managed to push the plane into a climb — but not before flight 902 came within 72 feet (22m) of striking the approach lighting pier before runway 22L.
The crew quickly reported that they were abandoning their approach, telling the controller, “We had a pretty good shear pulling us to the right and down, visibility was nil, nil out over the marker… correction, at 200 feet, it was nothing.”
“Okay,” the controller replied, “the shear you say pulled you right and down?”
“Yeah,” said flight 902, “we were on course and down to about 250 feet. The airspeed dropped to about 10 knots below the bug and our rate of descent was up to 1,500 feet per minute, so we put takeoff power on and went around at a hundred feet.”
On board Eastern Airlines flight 66, by now out of holding and headed for the airport, the crew listened in as their colleagues on flight 902 gave their report to air traffic control. “You know, this is asinine,” said Captain Kleven. Why on earth were they still being asked to approach runway 22L if the conditions were so bad?
“I wonder if they’re covering for themselves,” another crewmember said, suggesting that perhaps Eastern 902’s report might be exaggerated.
The crew technically could have asked to land on a different runway, but this could cause a delay of up to 30 minutes while air traffic control found a safe route for them through all the other traffic. With their relatively limited fuel, that might not leave them with a safe margin if they failed to land, especially since conditions were equally bad at LaGuardia. Captain Kleven didn’t feel like he had much choice but to land on 22L like everyone else, and believing that flight 902 was exaggerating its report helped him rationalize the decision to proceed.
With First Officer Eberhart at the controls, flight 66 locked on to the instrument landing system and began to descend toward the runway. Ahead of them, a Finnair DC-8 flew into the same shifting winds, but the crew anticipated the conditions and were able to fly through to a safe landing with minimal altitude loss. A private Beechcraft Baron followed it down, largely unaffected by the downdrafts due to its much smaller surface area. Neither plane reported the conditions they encountered, believing that the controller was already well aware of the problem.
The problem, as the Flying Tiger and Eastern Airlines pilots told the controller, was wind shear. Wind shear is a sudden change in wind direction over a short distance, most often associated with thunderstorms. Although wind shear can take many forms, the most dangerous type is a “decreasing headwind/increasing tailwind” scenario. Flying into a headwind increases the speed of the plane relative to the air (airspeed) and therefore increases lift. Pilots who suddenly encounter a large headwind might even reduce thrust to prevent the plane from climbing. So if that headwind were to suddenly disappear — or worse, turn into a tailwind — the consequences could be significant, as the plane’s airspeed will drop abruptly, lift will decrease, and the aircraft will start to descend, sometimes at a high rate of speed. A downdraft concurrent with a decreasing headwind will exacerbate its effects even further. As the crews of both Flying Tiger Line flight 161 and Eastern Airlines flight 902 discovered, maximum thrust may be required just to prevent the plane from descending under such conditions. Indeed, pilots were trained to prepare for known wind shear conditions by adding 10 or 15 knots to the normal approach speed, ensuring that they could easily accommodate a sudden loss of airspeed upon encountering the wind shear. But in this case, even more was required: the Finnair pilots had to add more like 25.
As flight 66 descended toward the runway, the controller called flight 902 again and asked, “Would you classify that as a severe wind shift — correction, shear?”
“Affirmative,” said Eastern 902.
That was enough for First Officer Eberhart. “Gonna keep a healthy margin on this one,” he said, increasing their approach speed.
“Uh, I would suggest that you do,” someone said.
“In case he’s right,” Eberhart added.
It was a good call. But he had no way of knowing that it wouldn’t be enough to save him.
As the pilots ran through the landing checklist, Captain Kleven began looking for the runway. At around 500 feet, the plane suddenly flew into a shaft of heavy rain, and the windshield wipers had to work so hard that they could be heard over the engine noise on the cockpit voice recording. Nevertheless, at 16:04, Captain Kleven announced, “I have approach lights.” The runway would surely come into view at any moment.
“Okay,” said First Officer Eberhart.
“Stay on the gauges,” Captain Kleven said.
“I’m with it,” Eberhart affirmed.
By now flight 66 was pushing forward against a 25-knot headwind, but that was about to change. At a height of around 400 feet, a downdraft with a speed of about 5 meters per second (16 feet per second) struck the plane from above, pushing it below the glide slope. The headwind started to decrease, rolling back to 20 knots while the downdraft increased in strength to 6.4 meters per second. Then the headwind almost entirely disappeared, falling to just five knots in a matter of seconds. The plane began to lose airspeed, dropping rapidly toward the ground.
But Captain Kleven’s attention was elsewhere. “Runway in sight!” he announced.
First Officer Eberhart looked up to confirm. “I got it,” he said. Switching fully to visual flight, the crew abandoned their instrument scans, not realizing that their descent rate had increased from 675 to 1,500 feet per minute.
Seconds later, Eberhart suddenly realized that something was terribly wrong. “Takeoff thrust!” he shouted, pushing the engines to max power. Someone yelled something unintelligible. But it was already too late. There wasn’t enough time to stop the wind shear from pushing the plane straight into the ground.
At 16:05 and 11 seconds, the 727’s left wing began to strike the 30-foot towers supporting the approach lighting pier. The wing started to disintegrate and the plane rolled 90 degrees to the left, carving a trench through the ground as it came down on its side. Then the fuselage plowed into the approach lights again, tearing through towers 13 through 17 before slamming into the ground. These six massive impacts ripped the plane apart, sending debris tumbling onward toward Rockaway avenue as the ruptured fuel tanks burst into flames. Traffic on the busy thoroughfare suddenly ground to a halt as shattered chunks of the burning plane came to rest in the middle of the boulevard, but miraculously no cars were hit.
In the back of the plane, the only area that was substantially intact, the two aft flight attendants realized that they had survived the crash with only moderate injuries. Both escaped through what was left of the rear exit doors and emerged into a scene of total devastation. Pieces of the plane, pieces of the approach lights, and bodies of victims lay scattered for several hundred meters through the driving rain. Most of the fuselage had disintegrated, but in the rearmost rows a few people — some of them ejected from the plane while still strapped into their seats — had also managed to survive. As emergency crews arrived on the scene, they pulled some 13 or 14 survivors from the wreckage, all of them except the flight attendants suffering from various degrees of burns, many of them in critical condition. By the end of the day several of them had died of their injuries. Another died in hospital nine days after the crash, bringing the final death toll to 113 with only 11 survivors.
From the beginning, investigators suspected that the weather probably had something to do with the accident. Two planes had reported severe wind shear on approach to runway 22L just a few minutes before the crash, and witnesses reported an intense thunderstorm around the time of impact. Some even claimed they saw the plane get struck by lightning.
By comparing the actual performance of the plane during the approach against its theoretical capability, investigators were able to derive a model of how the wind affected flight 66 as it came in to land. The findings suggested that the ill-fated flight flew into extreme wind shear at the very margin of its capability to penetrate safely. A 25-knot headwind disappeared in seconds, at the same time as the plane was struck by an intense downdraft. Even a prompt application of maximum thrust may or may not have been enough to save the plane.
The flight data recorder from Eastern 902 revealed that it flew through conditions very similar to those encountered by Eastern 66. On that flight the pilots reacted quickly by pitching the nose up and applying max power, but even so they only barely managed to avoid a crash. It was clear from the data that the weather conditions on approach to runway 22L were way beyond what could be considered safe to fly through. So why did so many planes keep flying through it?
The local controller first became aware of the severe wind shear when Flying Tiger Line flight 161 reported it moments after landing. But despite the DC-8 captain’s dire report, the controllers did not change the runway in use. By examining the procedures used in the control tower, the National Transportation Safety Board was able to figure out why.
At Kennedy Airport, controllers used a computer program to decide which runway to use at any given moment. The primary consideration was not safety, but noise abatement. They were required to avoid landing planes on the same runway for more than 6 hours at a time in order to prevent excessive noise over nearby neighborhoods. They were allowed to violate this rule if safety required them to do so, but their working policy was to follow whatever the computer program said as long as the wind speed over the runway was 15 knots or less. If it was more than this, then safety became their primary consideration.
When the DC-8 captain reported severe wind shear on approach and asked the controller to change the active runway, the controller saw that the indicated wind speed was 15 knots — within the limit — and that it was aligned perfectly to give inbound planes a headwind, which is ideal for landing. As a result, the controller didn’t suggest to his supervisor that the runway be changed, and the supervisor later told the NTSB that even if he had been informed of the DC-8’s report, he wouldn’t have changed the active runway because the wind favored 22 Left. Contributing to this decision was the fact that the alternative runways — 31L and 31R — had already been used for six hours that day, and as long as the wind was 15 knots or less, their policy was to not use those runways again.
Thus the controllers believed that the wind speed was moderate and that the wind was aligned perfectly for landing on runway 22L; the computer program told them runway 22L was the ideal runway to use; and changing the runway on short notice would cause major delays and increase their already high workload as they maneuvered all the inbound airplanes over to the new approach path while ensuring they maintained a safe distance from one another. As far as the controllers were concerned, there was absolutely nothing to justify such an inconvenience.
The fundamental problem was that pilot reports were the only way for the controllers to know what the winds were like on approach, but their criteria for deciding the active runway didn’t take pilot reports into account at all. Furthermore, controllers were judging wind conditions based on readings from a single anemometer located half way down the runway, and apparently did not appreciate the fact that in stormy conditions, wind speed and direction could vary significantly just between the location of the anemometer and the point of touchdown, let alone further back along the approach path.
With the controllers continuing to vector all inbound traffic onto runway 22L, it would have been very difficult for the crew of Eastern Airlines flight 66 to request a different runway. The resulting delays would leave them with a margin of fuel much too low for comfort, especially if they had to divert to LaGuardia. (Their fears in this regard mirror an event that occurred more than15 years later. In 1990, Avianca flight 52 crashed in Cove Neck, Long Island, killing 73, after running out of fuel on approach to JFK International Airport. The flight had been in holding for a long period, then abandoned its first approach to JFK after wind shear almost caused it to crash. The plane ran out of fuel before it could complete its second approach. The circumstances leading to the accident shared a number of similarities with those faced by Eastern 66.) With such a scenario in mind, the pilots would have been very unlikely to request a different runway without at least trying runway 22L first. They rationalized away Eastern 902’s report of severe wind shear, then their confidence was further boosted when two more planes ahead of them landed without reporting any difficulties. They had no idea that the Finnair DC-8 landed during a relative lull, and only got through safely by increasing their airspeed significantly.
Although the crew of flight 66 did increase their approach speed somewhat in response to the report from flight 902, their preparations were inadequate to counteract the incredible strength of the wind shear that they encountered. A very prompt application of takeoff power and aggressive nose-up inputs might have saved them, but the pilots had no idea that such drastic measures would be necessary. Consequently, they paid more attention to searching for the runway. Indeed, right as the wind shear reached its peak intensity, the captain spotted the runway, causing the other crewmembers to divert their attention away from their instruments. The wind shear wasn’t accompanied by any appreciable turbulence, and in the low-visibility environment it wasn’t immediately obvious that they were sinking rapidly. By the time the crew realized that the wind shear was pushing them into the ground, it was too late to save the plane.
Using the wind model derived from flight 66’s black box, the NTSB developed a simulator scenario based on the accident and observed how 727 pilots reacted to the conditions. Of 54 simulated approaches, 18 ended in a crash. Of the 36 simulated approaches that did not end in a crash, 31 ended with a go-around, and only five continued to a safe landing. Pilots who recognized the wind shear early generally made it through, but those who recognized it too late, or who were insufficiently aggressive in their response, did not. After the simulator runs, eight of ten pilots who commented said that they might have crashed if they were flying Eastern 66, and seven of ten said that switching to visual flight when the runway came into view at 400 feet would have significantly delayed their recognition of the wind shear.
With these results in mind, it was clear to the NTSB that the crew of flight 66 hadn’t appreciably deviated from what any 727 crew would do in their situation. And that could only lead to one conclusion: that there was a fatal flaw with America’s airways, and if they didn’t do something about it, this would surely happen again. In its final report on the crash, the NTSB explicitly stated that judging the actions of individuals involved in the accident wasn’t useful, because the system itself was at fault. “All parts of the system must recognize the serious hazards that are associated with thunderstorms in terminal areas,” they continued. “A better means of providing pilots with more timely weather information must be designed.”
After the 1973 crash of an Ozark Airlines Fairchild FH-227 in St. Louis, the NTSB had recommended that a ground-based sensor system be developed to detect wind shear near airports. But by 1975, no appreciable progress on such a system had been made, a fact which the NTSB lamented in its report on the crash of Eastern Airlines flight 66. But this time, with over 100 dead at one of the busiest airports in America, authorities listened. As a direct result of the crash, the FAA helped develop the Low Level Wind Shear Alert System, or LLWSAS (LLWAS today), a network of anemometers surrounding an airport that can detect divergent wind directions and velocities and sound a “wind shear” alarm in the control tower. By 1977, just two years after the accident at JFK, the system was already being installed at major airports across the United States.
Many other safety improvements also came as a direct result of the crash of flight 66. The NTSB recommended that a standardized scale be created to categorize thunderstorms according to the danger they pose to aircraft; such a system was indeed implemented within a short time after the crash. Thunderstorms began to be designated according to a well-defined intensity scale from 1 to 6, where anything over 3 is to be avoided at all costs, and controllers and pilots alike were taught how to use the scale. The NTSB also recommended that separate anemometers be installed for each runway; today, such a configuration is standard, and at major airports there are usually several anemometers positioned at different points along the runway. On the basis of yet another NTSB recommendation, the FAA began requiring that all new structures near runways, such as approach lighting piers, be made frangible so that they don’t do so much damage to airplanes during accidents. The FAA also promised to retrofit earlier structures if funds were made available, although this effort ended up taking decades to finish. Other recommendations included that the National Weather Service ensure pilots and controllers are provided with timely information about the presence of thunderstorms near the airport; that controllers use the presence of thunderstorms as part of their criteria for determining the active runway/s; and that pilots be trained on the specific characteristics of low level winds associated with thunderstorms.
According to the FAA, at the time of the crash of Eastern 66, there were no specific regulations pertaining to wind shear. In order to develop such rules, more research needed to be done. In the aftermath of the crash, the NTSB and the FAA worked with a team headed by famed meteorologist Ted Fujita, inventor of the Fujita scale of tornado intensity, to understand the mechanics of wind shear. Fujita’s study was the first to identify the phenomenon that he referred to as a “downburst cell,” known today as a microburst. In a microburst, cold air at the top of a thunderstorm sinks past hot air below it until it strikes the ground in a localized area and spreads out in all directions. Horizontal wind speeds within a microburst could sometimes be extreme, with momentary gusts as high as hurricane force, and were often accompanied by high-speed downdrafts and heavy rain. These conditions were found to develop within a very short period of time, sometimes a minute or less, far faster than most pilots and controllers assumed. And most horrifyingly of all, the study observed microbursts containing wind shear so violent that it exceeded the ability of any aircraft to recover control. This ran counter to the prevailing belief in the aviation industry that wind shear could always be safely penetrated as long as pilots were prepared to apply extra thrust and pitch up to escape.
The notion that there were downbursts which no airplane could penetrate took a long time to catch on in the aviation community. Despite Ted Fujita’s groundbreaking research, it would take around 10 years and two more crashes before pilots, controllers, dispatchers, and regulators all agreed that such phenomena really did exist, and the industry’s philosophy for dealing with wind shear consequently shifted from recovery to avoidance.
But while future accidents would continue to reveal gaps in the system, there would have been no system at all without Eastern Airlines flight 66. Many of the tools and procedures used today to keep planes away from thunderstorms and inform pilots about localized weather conditions trace their roots back to the initiatives spawned from this crash. And although these reforms didn’t totally eliminate the risk of wind shear accidents, without the changes even more lives surely would have been lost.
Today, Eastern Airlines flight 66 is not particularly well remembered. But the crash really did spark an underappreciated safety revolution that still affects everyone who flies. The long road to understanding wind shear began on that stormy afternoon in 1975, and thanks to the actions of the NTSB and the FAA, the problems that led to the disaster have been all but eliminated. Air traffic controllers today receive detailed weather information gleaned from a variety of sources including many sensors located around the airport, allowing them to quickly make informed decisions about where to direct traffic and what runways to designate for takeoffs and landings. Modern cockpits are equipped with devices that can detect wind shear well in advance and warn the crew. Pilots are rigorously taught to avoid flying through thunderstorms. No single accident is responsible for this safety net, but Eastern 66 is undoubtedly where it started. 46 years later, we can look back and say that the 113 passengers and crew who lost their lives that day did not die in vain.
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