Autolanding a plane is not only possible, but may be required in certain weather conditions.

Did you know that the ability of an airline to get you on the ground on time in extremely poor weather hinges on the type of airplane? If an airplane and its pilots are certified to autoland in bad weather, your aircraft will be able to touch down safely and get you to your meeting, while other aircraft may need to divert or circle.

Most major U.S. and international airlines have stringent safety guidelines that require the airplane to be able to land itself via autopilot when the weather is below a certain minimum — usually a 200-foot ceiling and half-mile visibility. Most larger aircraft, usually from Boeing 737 or Airbus 319-320 size all the way up to the 747-400, have Category III capability. This means the plane and its pilots are certified by the Federal Aviation Administration (FAA) to operate the aircraft in an autoland capacity. (The actual requirements of pilots, aircraft and runway are lengthy, so we’ve simplified here for clarity.) Believe it or not, the autolanding is usually so smooth, you probably won’t notice the difference as a passenger.

In good weather, it is common for the pilots to “hand fly” the airplane during climbs, descents and landing. But when the weather is particularly bad, pilots will often engage the autopilots and fly the airplane by twisting knobs and pushing buttons. While this might seem like an effortless activity—it’s not. Even with the aircraft on autopilot, getting it into the proper configuration at the appropriate speed with the flaps extended and the landing gear down is very demanding. This does not happen automatically, and is usually completed in instrument conditions without visual reference to the ground, making an already difficult procedure that much more difficult.

It takes all three of the aircraft’s fully functioning autopilots for a Category III approach. (The redundancy is a backup system for safety, in case one fails.) They track an invisible Instrument Landing System (ILS) beam all the way to touchdown. At a certain height above the runway, the autopilots will retard the throttles, flare at a precise altitude and touch down gently. Then, as the wheels start to spin and the autopilots sense the weight of the aircraft on the runway, autobrakes slow the aircraft to a safe taxi speed for exit off the runway.

During the landing, there are two things that do not happen automatically: The captain must engage the thrust reversers, and the autobrakes and autopilots must be disengaged. The pilots then taxi the airplane to the gate manually.

Does this mean that if you are not traveling on a Category III–capable airplane, your safety is compromised? Absolutely not. It just means that the pilots may not be able to legally land if the weather is unusually poor. Passengers on Category III–capable airplanes have a better chance of touching down on time, while other aircraft may be stuck in holding patterns waiting for the weather to improve.

On the other side of the coin: If your plane can land itself, is your safety compromised? Again, absolutely not. The Category III approach is the safest and most reliable way of allowing large numbers of aircraft in and out of our airports without incurring numerous weather-related delays.

The excellent commercial aviation safety record of major airlines in the
United States can be largely attributed to enhancements and redundancy in automation of aircraft systems—but the most important factors in this impressive safety record are improved training programs and a dedicated group of professional pilots.

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CHRIS COOKE is a pilot flying internationally with a major U.S. carrier. He can be reached at editor@executivetravelmag.com.