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An Aircraft Slides Off A Slick Runway: How To Avoid The Same Mistake On Your Next Flight

CDN Aviator

Now that winter is here in many parts of the country, it's time to start paying extra attention to runway conditions. A contaminated runway plays a significant role in your ability to slow down, stop, and even maintain control during landing.

The Accident

The following NASA ASRS report from early 2017 tells one pilot's story of an encounter with a contaminated runway...

I listened to the ATIS information, then checked in with approach control, and accepted the plan to shoot the RNAV Runway XXL approach, with a circle to land Runway YYR. At this point the visibility was 1 1/2 miles with a ceiling of approximately 1,200' overcast. Approach control vectored my aircraft for the Runway XXL approach. The aircraft was in IMC conditions throughout the descent and approach. It began picking up light to moderate rime ice. Approach handed me off to tower inbound on the Runway XXL approach.

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I checked in with the tower. Tower informed me that the ATIS changed and that the visibility was reduced to 3/4 mile. I requested to continue the approach to straight in Runway XXL. The tower cleared us as such. No mention of runway conditions were given by the tower. I descended on the approach, and saw the airport lights and runway environment at the MDA. Being in a position to land, I continued down to the runway. I was using an extra 5kts of speed on approach due to residual ice on the aircraft.

I believe that touchdown occurred somewhere in the first 1,500 feet of the 3,200 foot runway. Upon touchdown, I realized the braking action was nil and that the aircraft was sliding. I was aware that it had been lightly snowing at the airport, but was not aware the runway had not been plowed or treated in any way, and was not offered any information to that affect. I maintained directional control of the aircraft but ran out of runway surface by about ten feet, striking a runway end light. I was able to taxi the aircraft to the ramp without further incident. The aircraft's props were damaged. No other damage was known at the time of this report.

When does the ATIS include runway condition reports?

When airport operations conducts a braking action test, they issue a NOTAM for the braking action. And as soon as tower gets that, they'll include it on ATIS. Until then, there might not be any runway condition information on the ATIS.

When you're picking up ATIS, you'll hear something like this: braking action 5/4/2. But what does that mean? If you look at the chart below, it means the braking action for the runway is good at touchdown, good to medium at the midpoint, and medium to poor on the rollout. When you see braking action numbers, the bigger the number, the better the braking action. The scale is from 0 to 6. 0 means nil braking, and 6 means dry runway normal braking action.

What will the tower tell you?

If you ask tower for a braking action report, they're not going to use the numbers. They'll stick with the words that describe the braking action: good, medium, poor, and nil. The word "fair" has been tossed out the window, per new guidelines established in 2016.

Even if a runway condition report is NOTAM'd for the airport, the tower is not required to give you a conditions report over the radio. It's your responsibility to listen to the full ATIS and obtain this information yourself. This is one reason that ATC always verifies with pilots that they have received the correct and updated ATIS information. If conditions are rapidly changing and the ATIS isn't representative of the true conditions, tower may give you updated runway information directly. Again, this is at the tower's discretion and is not required. If you're unsure of the conditions or have a question, it's always best to ask.

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Landing Fast And Long

The pilot in the accident flew a faster than normal approach to the runway due to ice accumulation, which was a most likely a smart choice. But the landing problems also started there. When you fly a faster than normal appraoch, you're more likely to float and land long. And when you touch down faster than your touchdown speed, you need more runway to stop.

Couple the landing point, longer required rollout, slick conditions, and a 3,200 foot runway, and it was the perfect recipe to end up off the runway.

What If It Happens To You?

If you're faced with a slick runway, or you're flying faster due to ice buildup on your airframe, there are a couple things you can do. First, pick a landing point closer to the runway threshold. In normal situations, aiming for the aim point markings (1,000' down the runway) is usually a great idea. But if the runway is slick, give yourself more time to stop. The 500' markings are a good place to start. And if your runway doesn't have 500' markings, the second centerline stripe is a good approximation. That extra 500' of stopping distance can make a big difference.

Maintaining Directional Control After You Touch Down

When you touch down, maintaining directional control should be your first priority. Use aerodynamic braking to slow down, and use small rudder inputs to maintain the centerline. Over-controlling the rudder could cause you to slide and lose directional control.

On slick surfaces, your brakes are going to be much less effective, and they can quickly get you in trouble. Initially after touchdown, use little to no brakes. Then, gently press them to feel their effectiveness. It's easy to get anxious and jam on the brakes, but that can easily lock up your wheels. And when that happens, your braking effectiveness decreases, and you can start sliding. The more gentle you are on the brakes, the easier time you'll have maintaining directional control on the runway.

Your Last Resort: Go-Around

If you have enough runway and braking/directional control is clearly a problem, going around even after touchdown is an option.

During a go-around, adding throttle increases airflow over your tail, and you'll most likely have better directional control on the ground with the rudder (even considering left-turning tendencies). If you feel like you're not going to maintain control on the runway or stop in time, go-around, lift off, and execute your Plan-B. That might be making another attempt at the airport, but it might also mean flying to another airport with better runway conditions.

Preparing For Less-Than-Ideal Landing Conditions

Next time you fly, pay attention to the runway conditions. We're just entering the season for slick runways, and if you're not prepared, you can find yourself in a lot of trouble, in almost no time at all. Know the runway conditions, give yourself enough runway to stop, be gentle on the brakes, and fly your airplane all the way to the taxi turnoff.

Swayne Martin

Swayne is an editor at Boldmethod, certified flight instructor, and commercial pilot for Mokulele Airlines. He holds multi-engine and instrument ratings, and is an aviation student at the University of North Dakota. He's the author of the articles, quizzes and lists you love to read every week. You can reach Swayne at swayne@boldmethod.com, and follow his flying adventures at http://www.swaynemartin.com.

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