Know Your Taxi Limitations

Mike Lenz
Reprinted with permission from FAA Aviation News

“A man’s got to know his limitations.” This famous line from the Dirty Harry film “Magnum Force,” starring Clint Eastwood, (a pilot, by the way) can apply to aviation, and specifically to safe taxiing.

The next time you receive a taxi clearance, think about any potential hot spots and limitations along that route and try to personalize the hazard areas that could apply to you while taxiing.

Visualizing these areas in advance can go a long way to keep you safe.

Let’s look at an example. Let’s say you’re at Daytona Beach International Airport (DAB) and you’re starting out from the general aviation parking area. Ground control instructs you to taxi to Runway 7R via Taxiway Whiskey (W) and Sierra (S).

Where are the hot spots on this taxi route? (See figure 1.) Three come to mind:

• The first hot spot along Taxiway W is. The parallel runway 7L, which your taxi instructions authorize that you, may cross, absent a hold-short restriction. Yet, controllers are human and can make mistakes. What if the ground controller did not coordinate your crossing with the other controller responsible for landings and departures on Runway 7L? This is considered a “high energy” part of the runway because the middle two-thirds of a runway is where landing and departing aircraft are often traveling too fast to stop safely or take evasive action.
• Also, aircraft have been known to land on the wrong parallel runway, and this is a possibility at DAB. Some pilots lose communications, or become disoriented, and land without contacting ATC. It’s rare, but happens several times each year and can easily lead to a runway incursion.
• When approaching Runway 7L, check for traffic landing or departing from either direction before proceeding and, if the frequency is not crowded, announce you’re crossing Runway 7L.
• And if you aren’t absolutely sure, call ground control before crossing 7L.
• As you continue your taxi down Whiskey what if you mistakenly turned left on Sierra, instead of right? You could inadvertently cross Runway 16/34. This is not good, especially since Sierra crosses Runway 16/34 near another high-energy part of a runway. Dirty Harry would ask, “What’s my limitation?”

The answer: Runway 16/34. If you see you’re about to cross, because you suddenly notice a hold line or a runway sign, you have probably turned the wrong way. In this case, stop, unless you are already on the runway, in which case you should exit the runway expeditiously and call Ground Control for further instructions.

• The third hot spot is at the point where you could miss the right turn from Taxiway W to S. Your limitation is—you guessed it—Runway 7R. If you’re about to cross 7R while still on Taxiway W, you’ve inadvertently passed up Taxiway S. Remember: When cleared to a runway, unless you have also received a “taxi into position and hold” or a takeoff clearance, you are not authorized to enter that runway.

It’s easy to make up scenarios like the ones described. The only problem is these, and too many others like them, are real. In fact, the third hot-spot scenario described was from an actual Category A runway incursion. (Category A events are runway incursions in which separation decreases and participants take extreme action to avoid a collision or a collision actually occurs.)

In this DAB event, a student pilot did stray onto Runway 7R, and a departing Cessna 172 saw the student enter the runway “and believed a collision was imminent if he rotated (the pilot had reached 55 knots) and instead tried to stop…” The student pilot stopped as well and the aircraft missed each other by 10 feet.

During your next taxi, visualize the hot spots and “know your limitations.” You can also make it interesting by challenging another crewmember, when available, to select the hot spots and limitations while you do the same. Then, compare notes. Did you each come up with the same ones? Did one crewmember miss one? If you missed one, buy the other pilot a cup of coffee, because you owe him or her at least that much.

Mike Lenz is a program analyst in Flight Standards Service’s General Aviation and Commercial Division and also a pilot.