Seeking Subtle Signs of Trouble

Seeking Subtle Signs of Trouble

By Robert N. Rossier, EAA 472091

This piece originally ran in Robert’s Stick and Rudder column in the April 2020 issue of EAA Sport Aviation magazine.

We don’t typically think of taxiing as a critical phase of flight. We mosey along at slow speed while keeping the nose wheel or tail wheel on the yellow line, watching for signs and obeying the markings. Simple, right? It’s a Sunday stroll in the park. But the truth is, there’s a lot going on during taxi and there’s a lot the pilot needs to be doing to stay on top of the situation. If we don’t get it right, there’s a potential for some very real excitement just getting to the runway, or soon after takeoff.

Flight Control Position

Especially on a windy spring day, it’s important to be aware of the relative wind while taxiing and make the correct control inputs to avoid an unintended upset. With a strong enough wind, we could find ourselves in trouble before we even get to the taxiway. One day a good many years ago, I watched a pilot taxiing in from the runway during particularly windy conditions. As he headed onto the ramp, he had a roaring tailwind that was pushing his tail up and hence his nose down. He clearly recognized the low-nose condition and hauled back on the yoke as hard as he could to pull the nose up. What he wasn’t recognizing was that with the wind behind him, he needed to move the yoke in the opposite direction and position the elevator in the down position to stop the wind from lifting the tail. With no radio available to warn the pilot, all we could do was watch. Finally, the wind got the best of him, and the prop ground into the tarmac, sending a blizzard of sparks into the air. It was an expensive mistake — and one that could have been easily avoided had the pilot followed the proper technique.

One way to avoid this problem is to first set the heading bug to the wind direction to help keep track of it while taxiing. To recall the proper elevator and aileron position, remember to fly up and into the wind if it’s in front of us (yoke back, ailerons into the wind), or down and out of the wind (yoke forward, ailerons out of the wind) when the wind is behind us.

Watching the Instruments

Another important task to manage is checking your flight instruments to see that they are working correctly. While they might all appear to be fine when the aircraft is stationary, we need to see what happens when we’re moving, particularly during a turn on the ground. The practice of checking the flight instruments during taxi, which takes just a second or two, can help to identify some problems that could present serious challenges once in the air.

As we make a turn, we need to watch for a few important things to happen. First, the turn indicator should indicate a turn in the proper direction with the ball swinging to the outside of the turn. Since the turn indicator is typically an electrically operated gyro, we can check for a flag indicating a power problem. If that’s the case, we’ll want to stop and then check that the circuit breaker powering the turn indicator is properly set.

The directional gyro (DG) should also indicate a turn in the proper direction as we turn the aircraft, but don’t forget to look at the compass to see that it is swinging freely. If the DG isn’t responding correctly, double-check that the vacuum system is working properly, providing adequate vacuum to drive the DG. Either way, we should have the problem checked out before flight. If the magnetic compass isn’t working, it is likely because of a fluid leak, which we might otherwise note by a kerosene odor in the cockpit.

During all turns on the ground, the attitude indicator should remain steady, upright, and unmoving, indicating a wings-level attitude. If it is moving unnaturally, or indicating something other than a wings-level condition, then we have a problem. Since it too is typically gyro-driven, we should again double-check the vacuum indicator to see that it is indicating proper vacuum.

Even for a planned VFR flight, having all the flight instruments in proper working order can be essential. While we might do fine in clear skies with less than a full panel, the situation can change unexpectedly should haze develop, visibility drop, or night fall. Instrument-rated pilots aren’t immune, either. Just a quick dash through a cloud deck to get up or down can be challenging if the instruments are amiss. A partial panel flight in IFR conditions can be an overwhelming challenge.

Brake Check

Although we should have already tested the brakes when we started the engine, it’s a good idea to do another brake check once we’re moving to verify their dynamic operation. Do they pull equally, or is one softer than the other? Do they drag? Does either feel spongy? While we might get away taxiing with less than perfect brakes, the problems could come when we’re attempting to land at the end of our flight. The time to find the problem is now before we launch into the bright blue beyond.

Developing Situational Awareness

One of the first things most of us like to do after engine start is put on our headsets and listen. It’s never too early to hear what’s going on and start creating a mental picture of the environment on and near the airport. One of the first things we want to do is check the weather conditions (automatic terminal information service, automated surface observing system, etc.), but at nontowered airports, we also want to listen in on the common traffic advisory frequency as soon as possible. Among the things we want to know: Who is taxiing where? Which runway(s) are in use? Is there any vehicle movement? Where is the traffic in the pattern? Are there any reports of runway problems (wildlife, birds, debris, ice, snow, etc.)? More than a few times, I’ve heard pilots reporting takeoffs or landings on cross runways and have been able to avoid conflicts that could otherwise have been disastrous.

Avoiding Distractions

Perhaps one of the biggest dangers during taxi is getting caught up in distractions, and it’s easier than we might think for that to happen. Casual chitchat with passengers can easily take your mind off what we should be doing, causing us to deviate from our normal taxi routine and miss important communication and other safety-related clues.

But it’s not just passengers who can distract us. Another way we get off track is to start setting up our navigation equipment while on the move — programming our GPS, inputting a flight plan, or completing other tasks that pull our eyes into the cockpit or divert our attention. As with texting while driving, tending to such cockpit duties while in motion can put us at significant risk.

While it seems like taxiing an aircraft to or from the runway might be the least worrisome phase of any flight, any undetected problems can sneak up on us unexpectedly and put us in a compromised or even downright dangerous position. But if we develop the proper habits and pay attention to procedure and protocol during taxi, we can add a whole new level of safety to our flying.

Robert N. Rossier, EAA 472091, has been flying for more than 30 years and has worked as a flight instructor, commercial pilot, chief pilot, and FAA flight check airman.

Post Comments

comments