An “Autoland” refers to allowing the autopilot to land the jet. Many think that most landings are performed this way, but it’s actually the opposite – only a tiny fraction of landings are performed this way, and for good reason. “CAT III” refers to different categories of the “Instrument Landing System” (ILS). The ILS is something like a homing beacon, w/ both a horizontal & vertical element. The jet can decipher the signals to tell if it’s left or right of the runway centerline (the “Localizer”), and if it’s high or low on the “Glideslope”. Then it displays this information for the pilots so we can fly through the weather. Some of these signals can be used 20 or more miles away, and most autopilots are able to “couple” to the signals for navigating. The different categories, or CATs, are based on how low you can get to the ground before you either have to see the runway to land, or initiate a “Missed Approach” (basically a go-around). This is your “Decision Height” (DH). As the CAT numbers rise, the level of risk does, too, because the DH gets closer to the ground. Because the risk rises, the type of equipment used & the redundancies required increase with each CAT, as well. Most airports will have a CAT I ILS approach, but generally only major airports have a CAT III, and then only for certain runways. CAT III requires special runway lighting & antennas for the ILS, for example, so it’s an extra expense. Not all jets will be equipped for a CAT III either, and it requires special training for the pilots as well as procedures for the controllers. At my airline, only the Captain is allowed to fly a CAT III. A CAT I will usually get you to about 200’ above the ground (it varies) before you either have to see the runway or go missed. The autopilot can be on for this, but once you see the ground you must disconnect the autopilot & manually land. All commercial pilots are trained to this standard. CAT II might step you down another hundred feet, to 100’ above the ground, before you have to see the runway. A CAT III ILS can bring you all the way down to the runway, even when visibility is zero, but generally only for jets equipped with an “Autoland” system. The autoland requires some special features in the jet. It varies some by manufacturer, but the FAA publishes a list of minimum equipment required. This usually is all about redundancies…having two functioning radio altimeters, for example. If any of this equipment is missing or broken, you can’t do an autoland. The autoland system has to be tested in flight periodically, or after certain maintenance procedures. We do this on clear days, so we can monitor how it’s doing visually. It has to land within certain tolerances to pass the test. But, even on a clear day, it still requires special procedures & coordination. For example, the Tower has to keep other airplanes further away from the runway than normal. If one of them taxis in front of the ILS signal, it can mess it up & the jet starts following signals that are now no longer guiding it accurately. Which leads to a bad day. The autoland is further limited by environmental factors which pilots are not limited by. Reduced maximum crosswinds, for example, or maximum tailwind. Depending on the manufacturer, the autoland has different capabilities after actually touching down. And, by the way, it *usually* does a pretty nice job of touching down softly. It’s not the smoothest landing you’ve ever had, but it’s pretty good. Some will continue to track the runway centerline as the brakes slow you down…but others have no idea where they are after touchdown & head for the grass if permitted, so you have to turn off all automation immediately after touchdown. In any case, autoland is only used in a tiny fraction of landings. Most of the time, it’s the pilot, doing it manually, often just using visual references. The airlines want it that way…over-reliance on automation creates pilots that can’t fly when automation fails.