Sunday, July 30, 2017

Too Close for Comfort

A Beautiful Day Not To Look Out the Window

Date Aircraft Route of Flight Time (hrs) Total (hrs)
30 Jul 2017 N21481 SDC (Sodus, NY) - ROC (Rochester, NY) - 5G0 (Le Roy, NY) - SDC 2.3 1673.5

"Cherokee Four Eight One, five miles from SUUSA, maintain VFR, cleared for the ILS-28 approach, contact Tower one one eight point three."

It was a perfectly beautiful morning, but I could see only the Warrior's instrument panel owing to the Foggles that I was wearing. Rather than looking outside, I was chasing phantom paths through the sky, riding invisible radio beams and tracking courses synthesized within the electronic brain of the ship's GPS.

A few days before, I polled a group of friends in hopes of finding a safety pilot, someone to look outside while I practiced some instrument approaches and was unable to watch for traffic. It was my good fortune to get two takers, Jamie and Tom. Both are relatively recently certificated pilots, but meticulously careful and responsible. Not only did they enable me to get some instrument practice, but they got an introduction to what IFR flying (at least approach-phase IFR flying) is all about.

Ground track courtesy of FlightAware

"What's the Frequency, Kenneth?"

How did I do? I give myself a C+.

I flew five approaches: the ILS-28, RNAV-25, and ILS-22 at Rochester; the published missed approach for the ILS-22, which involves a hold with left turns at the Geneseo VOR; then the VOR-A into Le Roy with the published missed approach, a holding pattern with right turns at the Geneseo VOR; and, finally, the RNAV-28 back into Sodus. My interceptions of all courses were really crisp, the holds were flown well with only reference to VOR and timer, and altitudes were managed well. In fact, most of the approaches were flown as well as I have ever flown them. I like reviewing the ground tracks after each session because they provide an unbiased assessment of how well I hand flew each practice approach.

That sounds pretty good. So, why the C+?

As shown in the ground track by the dog-leg on the ILS-22 approach, I blew through the final approach course and had to turn back to intercept the localizer. This happened because I had the wrong localizer frequency tuned; the localizer frequency for 28 was still active and the 22 localizer frequency was in stand-by. Sometimes the flip-flop button on the GNS-430 is a little sticky and, though that may have been a factor here, it is beside the point. The problem is that I "verified" the frequency by listening to the Morse code identifier broadcast by the localizer. I clearly fell prey to confirmation bias and concluded that I heard the correct identifier even though I would have actually heard the ILS-28 localizer ID. This is a valuable lesson. It indicates that, even though I may think I am listening to those Morse code identifiers critically, that is clearly not the case. This is why we practice.

This is also where I envy Jamie. As a ham radio aficionado (expert? Zen master?), Jamie can translate Morse code conversationally in real time. He would not have made the same mistake that I did because his ear is far more discriminating to "dits" and "dahs" than mine.

"Still Lurking About"

The longest leg of the day's flying was 42 nautical miles, which came when we departed the last hold over Geneseo for JORAX, an initial approach fix for the RNAV-28 approach into Sodus. Though I was still under the hood, this should have been the most relaxed segment of the morning's flight. We listened to the trainee controller at Rochester Approach who seemed to be stretched to his limit working a few aircraft flying practice approaches into Rochester and Batavia. We heard him enter my friend Ed into the system for flight following as Ed flew his long, solo cross country (way to go Ed!).

N1185X

As I cross checked instruments, I noticed that the iPad depicted "company traffic" nearby. Eight Five X-Ray from the club was flying a meandering path north of us. I remarked on it to Jamie and Tom. A few minutes later, Rochester called traffic at our twelve o' clock. It was Eight Five X-Ray again.

Tom had it first, directly ahead at our altitude and tracking south across our eastbound path. I lifted my chin to peer out from under the Foggles and verified the tiny block dot, apparently no larger than a gnat,  moving along the horizon and across our path.

No factor, I thought.

"Cherokee Four Eight One has the traffic," I reported back to Rochester Approach.

In ForeFlight, the avatar of Eight Five X-Ray changed trajectory and turned toward us. I looked outside again. The little speck on the horizon was no longer tracking left to right across the windscreen. Its relative motion had nearly stopped. It was no longer a speck, either. It was rapidly becoming airplane-shaped and heading slightly to our right.

I banked steeply to the left, yanked the throttle to idle, and literally stuffed the yoke into the panel. We turned and dove. Once committed to this evasive maneuver, I saw Eight Five X-Ray change trajectory again. She was now heading directly at us.

Dammit! As Tom said later, shoulda gone right. I decided to go left rather than right because I did not want to turn into where Eight Five X-Ray was tracking. It was the best decision at the moment I made it, but the situation continued to change.

The Warrior's vertical speed indicator was pegged at -2000 feet per minute. The dive was steep enough that, still wearing the Foggles, I never saw Eight Five X-Ray pass overhead. Tom and Jamie certainly did. Tom later described getting a "beautiful view of Eight Five X-Ray's undercarriage". I wondered if it was well-cleaned.

At a 220+ knot closure rate, everything happened very quickly. In moments, Eight Five X-Ray was behind us, leaving several elevated heart rates in her wake. I climbed back to 3100 feet and intercepted our original course to JORAX. We completed the approach to a gentle full stop landing at Sodus and taxied back to the hangar.

Jamie volunteered to clean up the airplane (thanks!) while I took care of other post-flight activities. As we worked, I answered questions from Jamie and Tom about the instrument procedures we flew that morning.

Post-Processing

All three of us left the airport still processing the near miss. Jamie started the dialog that evening with an email asking some simple questions.

Did the system fail?

Was someone or something at fault?

Ultimately, I don't think so.
  • ADS-B gave us an early warning that Eight Five X-Ray was in the vicinity. We had the technology available, we made use of it, and it put us on alert.
  • I was flying simulated IFR under the hood with a safety pilot in the right seat and a knowledgeable and capable pilot observer in the back seat. They spotted the traffic and kept tabs on it, just as they should have. No failure there.
  • The controller at Rochester Approach, though green and nearly task saturated, also notified us of the nearby aircraft. His attention probably went elsewhere once I confirmed that we had the traffic in sight.
  • Finally, once it was clear that a conflict was likely, I acted quickly and decisively.
In other words, the system worked as it should have and everyone did what they were supposed to do. Since gaining ADS-B traffic capability, I have preemptively avoided other aircraft without ATC ever calling them to me as targets. I did not do so in this case because Eight Five X-Ray did not present as a hazard until she turned nearly ninety degrees toward us. It was this course alteration that rapidly changed the scenario from a non-event to a near miss.

I think that a lot of pilots still put stock in the Big Sky Theory, the notion that the sky is vast, our aircraft small, and the probability of encountering another aircraft midair is low. That may be true in some locations, but it is not universally true and certainly not true in the vicinity of an airport.

The Big Sky Theory is also a poor surrogate for risk assessment. Ultimately, risk is a product of two factors: the likelihood of an incident happening multiplied by the severity of the outcome if it does. While the Big Sky Theory may reduce the probability of a midair collision in some locations, that probability is far from zero (there is no such thing as zero risk anyway) and the severity of a midair collision is likely significant. From the perspective of risk assessment, the Big Sky Theory offers very little "protection".

This is why we fly simulated IFR with safety pilots, why we keep our eyes outside of the airplane in visual weather conditions whether flying VFR or IFR, why there is a market for traffic alerting gear (be it via ADS-B (TIS-B), Mode S (TIS-A), or detection of nearby transponders), and why many of us choose to operate on radar flight following when VFR. After all, it was the aftermath of a serious midair collision between commercial airliners over the Grand Canyon that led to the Federal Aviation Act of 1958, creation of the FAA, and a mandate for the new federal agency to regulate United States airspace.

All pilots know this already, but reminders never hurt. Stay vigilant.

4 comments:

  1. Always a good review and reminder. When I have a safety pilot I will brief for evasive action with the typical transfer; my plane, your plane, my plane, which gives me time to get out from under the stinking foggles. Once I'm under the foggles I also confirm the safety pilot is eyes outside only. I know its easy to look at the 530 or their iPad but its the eyes out we need. I'm guilty of raising the camera for a quick shot or two when acting safety pilot and despite clearing for traffic anything can happen. At least ADS-B does provide some advance warning.

    I flew with Mike B as noted in many blog posts and our crew interactions became one, simply out of familiarity. I fly with a couple differ pilots now that are not IFR rated but pilots I totally trust with my life. They are not as aggressive as mike but he was also a CFII and I think that definitely adds something to the mix. Oh how I remember those torture flights under foggles.

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    1. Thanks for your comments, Gary. Yes, we did the whole "my airplane" briefing as well. And the guys I was with are both really meticulous pilots who took their roles seriously. In our case, I looked up to see the other airplane turning toward us, and just acted.

      As an postscript, since I wrote this post, I have talked with the pilot of Eight Five X-Ray. He indicated that he turned toward us and descended (my passengers verified that we originally had good altitude separation) in an effort to see us. I am not convinced that turning toward an oncoming aircraft that you do not see and descending to their altitude is the best strategy for traffic avoidance. He did not see us until he passed directly overhead.

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  2. Pretty crazy. But you saw and avoided, so the system did of course work.

    Your left turn reminds me of when opposite-direction traffic suddenly appeared (and a sudden, rather urgent call from ATC about it) closing quickly on us in the 172 many years ago. I still remember that I was processing the controller starting to say he suggested a left turn while simultaneously yanking over into a steep left turn. Amazing how quick our brains work when necessary. Anyway, while not as close a call as this seems to have been, I also had to reverse course when I realized I actually needed to go right for avoidance.

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    1. We experienced the same conflict with our "almost" head on traffic. The training says to go right, but at the time, turning right seemed like a setup to exacerbate the situation. Even with a pair of bugsmashers, the closure rate is stunning and things happened quickly.

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