Even as the FAA decries pilots' over-reliance on the technology of their aircraft, they themselves over-rely on the technology of their safety systems. While seeking out answers for the April 25th incident, I was told by the FAA:

"Modern technology equips the airplanes with all these devices. It all worked properly, and because everything worked properly, [any investigation]'s probably not going to go a whole lot farther." — Hawaii FAA Inspector

The achievement of modern air travel, that precise choreography, instills a hubris in those tasked with managing it. The system and its safety record are so impressive that catastrophes that almost happen apparently aren't worth scrutiny. Instead, the FAA inspector told me that any changes would likely take place internally at the two airlines. The agency seems to rely on these companies, the creators of these infallible technologies, to self-police much in the same way that financial regulators relied on banks to self-police when it came to complicated products like mortgage-backed securities.

Source: Flickr

Imagine you're driving on the highway at night. Suddenly, another car driving the opposite direction appears in your lane. You swerve into another lane just as the car passes. The FAA's view would hold that nothing was amiss because your headlights revealed the oncoming car.

Clearly, in the car example and its April 25th plane equivalent, something went wrong. Someone was in the wrong place. On the ground, cars separate horizontally by always driving on the right side of the road. In the air, planes separate vertically: all eastbound flights cruise at odd altitudes (33,000 feet, 41,000 feet, etc.) while all westbound flights cruise at even altitudes (38,000 feet, 52,000 feet, etc.). Of course, plane travel has one dimension more than car travel, so its exponentially more complex. Planes take off and land, passing through odd and even altitudes in the process. They avoid weather. And their flight paths have 360 degrees of horizontal directions. Two planes flying into Paris, one from London and the other from Barcelona, aim nearly head on at each other but both qualify as "westbound" flights.

On April 25th, my United 1205 flight was on an eastbound heading from Kona to Los Angeles and had reached a cruising altitude of 33,000 feet. An odd-numbered altitude, so by the east-west/odd-even rule of thumb, we were on the right side of the highway. The US Airways flight coming at us was on the wrong side of the highway. Thankfully, my pilot saw the plane in our 'headlights' in time and swerved into a dive, but the lack of a disaster doesn't mean a grave, teachable error did not occur somewhere in the process.

A composite image of aircraft taking off shows the density of airport traffic (Flughafen by Ho-Yeol Ryu)

Near misses are terrifyingly common in high traffic areas near airports and major cities. According to an investigation by two Seattle news groups into the ASRS data, "on average more than 150 close calls are happening every day." Nonetheless, the vast majority of these close calls involve small aircraft at low altitudes, incidents on the ground at airports, or isolated issues involving a single plane. Commercial airplanes, at cruising altitude and far from high traffic areas, rarely come close to each other. The FAA confirmed as much, telling me that my incident of two commercial jets at cruising altitude passing close enough to each other to trigger an RA in the collision avoidance system is "very rare."

The car equivalent might be the distinction between driving in a parking lot and driving in a highway. Circling a parking lot, drivers often end up in the wrong place and cause a fender bender. Getting onto an off-ramp and heading west on an eastbound lane of a highway is a different story entirely. And one that likely doesn't end well.

The April 25th near miss was close enough to pass through the "RA Region"

Safety Technology

The system that ensures safe air travel, and that led my pilot to dive our plane on April 25th, is called the Traffic Collision Avoidance System (TCAS). Planes send out radio signals that create electronic "bubbles" around themselves. If two bubbles overlap, the system alerts the two pilots. The 'Traffic Advisory' (TA) Region gives the pilot information, but doesn't require any action. If two planes enter each others' 'Resolution Advisory' (RA) Region, the system flashes an alert and instructs each pilot to climb or dive their plane immediately. Following an RA is fundamental to safe air travel. In 2002, over southern Germany, two planes received RAs but one pilot followed the TCAS instruction to dive while the other ignored the TCAS climb order and followed air traffic controllers. Both planes descended, leading to a collision that killed everyone on board both known today as the Überlingen Disaster.

Typical TCAS Envelope

On my April 25th flight, the United pilot followed the RA he received and even had a visual of the oncoming US Airways flight. Considering the size of RA bubbles, we may have been only seconds from a collision.

It Just Takes One

Air travel is indeed extraordinarily safe. Before the July Asiana crash, the last commercial airline fatality in the United States occurred in 2009 with the Colgan Air Flight 3407. Considering the number of air miles traveled in the country every year, plane travel has "nearly zero accidents per million flying miles." Car crashes, minor and major, occur hundreds of times a day.

Colgain Air Flight 3407 crashed in upstate New York in 2009

Regardless, plane crashes hold a unique place in our fears: the fiery violence, the lack of control — they have a scale and spectacle that makes them loom larger than their actual threat. Similarly, more Americans are killed by vending machines than sharks every year, but more people fear sharks than vending machines. Perhaps most importantly, car crashes occur with a sliding scale: fender bender to freeway pileup. Plane accidents are more binary: either nothing goes wrong or everything goes wrong.

Economists call these the 'statistical life' and the 'actual life.' Whenever a speed limit is increased, more people are likely to die — to the public, these deaths are 'statistical lives,' without names or stories. When comparing car crashes and plane crashes, we're often considering the nameless numbers of car accidents to the stories and details of a single plane crash.

As a result, each plane crash seems to lead to new regulation or new training. Safety in air travel, much like security, is reactive to events. The shoebomber means we now have to remove our shoes. A single threat in England means we now have to surrender our liquids. A collision of two planes over Germany means pilots now have to follow TCAS over air traffic control.

Reactive policy is not defensive though; it prepares only for the dangers that have already come to pass. To be more robust, the agencies that manage air travel have to do two things: First, they need to collect more and better data. With the hubris of flying's relative safety, they see their data as a flat line of perfect safety with only a few blips of outlier catastrophes.

"Currently, the commercial aviation system is the safest transportation system in the world, and the accident rate is the lowest it has ever been. This impressive record is due to many factors, including improvements in aircraft systems (such as those mentioned above), pilot training, professional pilot skills, flightcrew and air traffic procedures, improved safety data collection and analysis, and other efforts by industry and government. However, incident and accident reports suggest that flightcrews sometimes have difficulties using flight path management systems." — FAA Report, "Operational Use of Flight Path Management Systems" (emphasis added)

If they make policies for the outliers though, they need to better collect the data between zero and one: the near misses, the errors that narrowly avoided their consequences.

Secondly, they need to communicate that data more openly and readily. To push the comparison between air safety and air security further, America's security apparatus had intelligence on the September 11th terrorist attacks, but the knowledge was spread across different agencies and too siloed away for the dots to be connected. In the aftermath of the attacks, information sharing was identified as a key improvement in our security system.

Safety threats grow in the shadows just like security threats. Sharing information across groups means more lights shining into those shadows and more opportunities to identify a threat. The only downside to granting more people access to information is more people may leak that information, as the security apparatus saw with Manning and Snowden. Safety threats are unseen gaps in process or training though, not terrorist groups that might be able to make use of leaked information. Airlines are the only party that might object to information sharing, as their bottom lines suffer if consumers see air travel as more dangerous.

Inspecting an engine of the PanAm 747 at Tenerife

Just Enough

Accidents don't occur because everything went wrong; they occur because just enough went wrong. Thankfully, air travel has become more safe with time, but that doesn't mean its technology is perfect. Had just one more thing gone wrong two weeks ago, two jetliners would have collided in the largest airline disaster in history.

As mentioned, the crash currently with the most fatalities is the Tenerife Airport Disaster, in which two 747s collided on a Canary Island runway in 1977. For that tragedy to occur, even nearly forty years ago when the safety system was much less advanced, a string of unlikely events had to occur:

  • A bomb explosion at the Gran Canaria International Airport forced planes to divert to the smaller airport on nearby Tenerife.
  • Dense fog eliminated visibility for air traffic controllers and pilots. Tenerife's small airport had no radar, and so without visibility, voice communication was the only way to locate the planes.
  • The pilot of the KLM 747 did not have takeoff clearance when he attempted to lift off and collided with the taxiing PanAm 747.
  • Tower communication with the two planes led to a radio interference in the KLM cockpit that prevented the captain's misinterpretation of takeoff clearance from being corrected.

The United flight two weeks ago had at least one thing go wrong. Two jetliners six miles over the Pacific don't come within scraping distance of each other without something going amiss. Thankfully, just enough went right that a disaster even beyond the scale of Tenerife was averted.