28 Jan Little Airplane/Big Sky – Why Aircraft Collide in Flight & How to Prevent It
I was a commercial helicopter pilot for 35 years. In my career, I racked up nearly 1.5 million miles across the ground, carried, as near as I can tell, about 100,000 passengers, and finished up with 12,500 hours of flight time in my logbook. The most important number? I ended up with an equal number of takeoffs and landings.
Kidding aside, considering the public perception of the helicopter business, this may seem like an astonishing outcome. Most people truly believe that helicopters are dangerous contraptions capable of all manner of unpredictable, mostly nasty behaviors. The truth is, as I often told my passengers, the dangerous part of my job was driving in to work.
But there is a real danger involved in the helicopter industry, partly because of the way helicopters are operated, and that’s the ever present peril of midair collisions. Most helicopter operations take place from what the FAA refers to as ‘unimproved areas’, that is, unmonitored heliports, crude landing spots in rural areas, and generally remote places where radio or radar oversight is nonexistent. The general rule calls for pilots to simply see and avoid each other. Seems straightforward enough. Even so, there are a number of midair collisions and near misses each year. Pilots do, of course, monitor radio frequencies, and ought to be constantly aware of the presence of other air traffic. But in the absence of an outside monitoring facility such as an FAA control tower, or other ATC facility, which situation is standard in the helicopter business, it’s up to the pilot to steer clear of other aircraft.
It goes without saying that a collision between two aircraft almost always results in fatalities. When one of those machines is a helicopter it always does. A fixed wing aircraft has the possibility, albeit remote, of recovering from a midair, and possibly, maybe, perhaps reaching the ground somewhat safely. A helicopter does not. Any time the main rotor system of a helicopter is disrupted the aircraft will crash. Done. So in many respects it’s incumbent on helicopter pilots to be constantly aware of other aircraft, particularly so when, as was the case in the recent New York midair, the fixed wing was likely operated by a private, possibly lower time pilot. In addition, though the investigation has just begun in New York, design factors may have played a part. Helicopters typically have much more visibility from the cockpit than a fixed wing machine. Airplane cockpits generally have more limited visual fields, particularly a low-wing plane where the wing itself acts as a blind spot to traffic beneath.
So how to prevent midair collisions? How to keep aircraft separated in flight when there’s little or no outside monitoring, no on-board technical prevention mechanism? Here are a few suggestions for students, or any other pilots with a desire to retire as I did with no such ugly incidents in their record. I did have a few close calls: one near collision in Vietnam at dusk; another near Dubuque Iowa one cloudless, sun-splashed afternoon in July; and another reasonably close call with an impressively large offshore marine bird that could have taken out my windscreen had I not avoided him.
There are those in the aviation industry, mostly younger or inexperienced pilots, who subscribe to the ‘little airplane big sky theory of midair avoidance. Simply put, those pilots believe that in so vast a region as the sky, and while presenting such a meager target, their opportunities for contact with another aircraft are nearly negligible. Even though instructors always demand that student (and all other) pilots keep their heads ‘on a swivel’, some pilots keep their focus inside the cockpit for long periods, glancing up only occasionally. So the first rule is to look outside the aircraft once in a while. A good rule of thumb would be, oh, like, every ten seconds–okay five seconds.
Another way to stay free of other traffic is to monitor the radio. Listen to the chatter, pay attention to who’s taking off, or who’s landing, and from where. Called situational awareness, it’s our best friend while flying, or looking for the car in a crowded parking lot.
Know where you are all the time. This may sound simplistic, but if you know where your aircraft is within a quarter mile at all times, and other traffic reports in that same box, you need to be looking. And don’t assume they see you. One of the big killers in aviation is complacency. It’s killed more pilots than running out of gas. A classic mishap several years ago involved a commercial 727 landing at San Diego which collided with a Cessna 172 in September 1978. The pilots of the big airplane reported that they had the aircraft in sight. But the plane they reported seeing was a third aircraft. They never saw the one they ran into, and 137 people died.
Another phenomenon that can cause midairs is called rate of closure. In free air the perception of speed is difficult to distinguish from a cockpit. Closing on another aircraft, an inexperienced pilot can misjudge the rate at which the two are approaching, and literally fly into the other machine. It happens, especially when a pilot believes he has plenty of time to react, and finds out otherwise.
As for the little sky theory, just as in the San Diego crash described above, the vast majority of midair collisions happen on a clear day within five miles of an airport. In the New York City example, the helicopter had just lifted from the heliport along the Hudson River and was ascending. It’s speculation at this point, but it appears likely that neither pilot saw the other, so there was no time to evade. This accident may have been prevented by more vigilance from both cockpits, particularly considering the congested corridor along the river.
Aviation accidents are not inevitable. They’re the result of human oversight, complacency, lack of attention, and disregard for limitations. As one of my instructors used to say, “We’re not inventing any new ways to crash”. Midairs can be prevented, with a healthy regard for just how congested the airspace really is–and getting more so all the time–cultivating a good habit of situational awareness, and using whatever resources are available in the cockpit and outside it, such as radar coverage, position reporting on the radio, and teaching passengers to look outside as well.