Incursion: Runway hold-short lines, surface movement areas & pilot deviations

Incursion: Runway hold-short lines, surface movement areas & pilot deviations

Incursion: Runway hold-short lines, surface movement areas & pilot deviations

You are on short final when tower directs a go-around. Maybe it is day VMC and you see the airplane, ground vehicle or creature that tower is worried about. Maybe they see a formation of geese or some deer headed toward your runway. Perhaps there’s a taxiing aircraft that is not responding to a hold-short call, maybe somebody pulled onto your runway unannounced or another airplane didn’t exit at a certain high-speed and it caught tower by surprise.

What if this happens very late at night when you’re 100 feet above DH in IMC and really low on fuel? As pilots, we do not know if the go-around call is because of something tower saw visually or a procedural requirement like spacing. If we continue and land, we do not know if we will actually hit something or just be closer than anybody would like. So, we go around. This is not a preferred event, nor oftentimes a procedurally simple one, but a go-around would be better than plowing into the offending plane, fire truck or herd of raccoons. 

Look Both Ways 

I was taxiing the Duke one day and cleared by ground to cross a runway at the approach end. An excellent technique is to always look left and right before entering or crossing any runway or taxiway; even if it is closed or not the active runway. We should do this when the tower is open, when tower is closed or when there’s no tower at all. Check to see if it is safe to continue just as you would when you step off the curb to cross the street as a pedestrian or railroad tracks in your car, lest we be squished like a grape. That day in the Duke, a Cessna 172 was on about a half-mile final. I did the check left-and-right thing and held short of the runway. I told ground that I’d be holding short for a bit, and after a hesitation they said thank you.

The FAA defines a runway incursion as any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle or person on the protected area of a surface designated for the landing and takeoff of aircraft. Approximately three runway incursions occur every day at towered airports in the United States and ATC is fighting some of the same causal factors, as are pilots: expectation bias, complacency and distractions. 

According to FAA data, approximately 65 percent of all runway incursions are caused by pilots; just over half. Of the mistakes made by pilots, 75 percent of them are caused by GA pilots. And it is not only the runways that are an issue when we are driving around on the ground, it is taxiways, ramps, holding areas and deice pads as well. 

Yellow Skid Marks

Non-movement areas are ramps and aprons and are typically not controlled by ATC. The movement area is all of the taxiways and runways and is under the control of ground and tower. The boundary between the ramp and the taxiway is defined by two yellow lines, one solid and one dashed. The solid line is on the non-movement side and the single dashed line is on the movement side. At the runway, the dashed line is double and on the runway side of the solid line. The way I remember which side is which, is that the dashed lines are like yellow tire skid marks and are always on whichever side of the solid line the airplanes are moving faster. Out on the airfield that is on the runway side of the solid line. Back at the ramp, the dashed yellow skid marks are on the airfield side of the solid line, away from the ramp. 

I’m based in Chicago with my Part 121 carrier and ground traffic there is continuous and oftentimes intense. I feel sorry for pilots that are less familiar with ORD because I know how they feel. When we go to CLT, MIA or IAH, I feel like a student pilot on a solo cross-country. My situational awareness becomes strained, especially during low visibility, when it is dark or when the painted markings are wet and shiny. Thank
goodness for an FO and the ability to see a real-time display of our aircraft on the airport diagram page. But occasionally that is not enough

Standby to Copy a Phone Number

My one-and-only pilot deviation (not at ORD and long since expunged) involved unauthorized crossing of a movement area boundary. Due to a poorly worded ATIS that conflicted with published procedures, our polished MD-80 was pushed back from the gate across a non-movement boundary and partially onto a taxiway, without us contacting ground first. 

They didn’t like it much and gave us one of those “standby to copy a phone number” radio calls. Me and my FO both filed an ASAP (NASA report) but our explanation was not accepted into the program and we received a “this will be in your official record with no further action necessary” admonishment. Crossing a ramp non-movement boundary like we did may disturb ground control’s plan for entropy in the universe (see “Control Freaks,” Twin & Turbine Feb. 2018), but an unplanned excursion onto a runway can cause an actual catastrophe.

What’s the Worst That Could Happen?

A terrorist incident at Gran Canaria Airport began a chain of events that led to the deadliest ground accident in aviation history. The terrorist incident caused flights to be diverted from Gran Canaria to Los Rodeos, including the two accident aircraft. The airport is 2,077 feet above sea level and drifting clouds were causing extremely low visibility. 

I’ve encountered this phenomenon on Mackinac Island, Michigan. Ceilings and visibilities on the mainland could be 1,000/3 while on the island, which juts up 740 feet above Lake Huron, it could be obscured and half-mile. Forty-one years ago, two Boeing 747’s, KLM Flight 4805 and Pan Am Flight 1736 collided on the runway at Los Rodeos Airport (now Tenerife North Airport), in the Canary Islands. The Pan Am flight missed a planned turn-off while back-taxiing. Then, confusion on the radio, non-standard phraseology and perhaps a rushed decision, led the KLM captain to take off without clearance and was the primary cause of the accident. Watch a re-enactment here:

Runway confusion is a subset of runway incursions and can result in us unintentionally taking off or landing on a taxiway or the wrong runway. In August 2006, the crew of a regional jet was cleared for takeoff on Runway 22, but mistakenly departed from runway 26, a much shorter runway. They crashed off the end of the runway. And lining up to land on the wrong surface is what happened at SFO last year and almost resulted in an accident with even more casualties than at Tenerife (see “Those That Will,” Twin & Turbine Sept. 2017). 

Thorough planning is essential for safe taxi operations. We should give as much attention to planning our taxi as given to other phases of flight, including confirming we are on the correct departure runway by using the compass and checking the runway number painted on the surface. And when landing, whether in VMC or IMC, we should use all available navaids and visual cues to verify we are lined up on the correct runway.

A go-around is not a preferred event, nor oftentimes a procedurally simple one, but a go-around would be better than plowing into the offending plane, fire truck or wildlife.

Expectation Bias

Expectation bias is a double-edged sword. It is what allows us to understand a busy radio frequency when a non-pilot can’t, it allows us to copy a complex clearance when a newbie would be lost, and it is what gives us our Spidey-Pilot-Sense (SPS—like ESP only better) when the poo hits the fan. 

We have learned what should come next, what to expect in a sequence of events and the logical and likely events that follow certain things. It is also what makes us taxi the wrong way, stop at the wrong spot and makes tower tell us to “standby to copy a phone number.” 

When the taxi route that we have used many times before, or the route we were expecting to hear as the most logical route, is not the one that they actually give us, our expectation bias (SPS) bites us in the behind and we mistakenly think that we heard what we were expecting to hear.

Chocks to Chocks

Like a tailwheel airplane, we need to fly our airplanes from chocks to chocks. Consult the airport diagram before and during taxi, write down and read back all instructions and look for hot spots on airport diagrams. Maintain a sterile cockpit: conversations should be restricted to taxi operations. Heads-down activities like copying a clearance, programming the avionics or talking to the back-seat passengers should be avoided. 

Over half of all incursions may be caused by us pilots and we certainly don’t want to hear “standby to copy a phone number.” However, 35 percent of the time it’s ATC. So even when we write it down and follow the clearance, there may be an incursion. It could be due to tower, ground, a critter or another pilot following their clearance. If the hair is standing up on your neck or you’re not sure, stop the airplane and get clarification. 

Then look both ways before stepping off the curb, lest you and your Spidey-Pilot-Sense get squished like a grape.

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