Ask the Captain: Can a passenger plane land itself?

— -- Question: Hello Capt. Cox, with today's computers and electronics, is it possible for a large commercial aircraft to land itself at a major airport?

— submitted by reader retired2005

Answer: Yes, many of today's airplanes are capable of autolanding. Using very stable signals from the instrument landing system, properly programmed, modern airplanes utilizing multiple autopilots simultaneously and carefully monitored by the pilots can land safely in near zero visibility automatically. The crews are specially trained, the ground transmitters are specially monitored, and the airplanes are specially certified. This capability is most often used in very low visibility conditions. It is wonderful to see this level of technology being utilized to keep our air system operating during inclement weather safely.

Q: I had a follow up question on your answer regarding low visibility approaches. Do pilots need a special certification to fly in Cat II or III conditions or is it just needed to perform an autoland? In your opinion, what percentage of commercial pilots have a Cat III autoland certification?

Thanks for doing this column, I throughly enjoy reading it every week!

— greg13

A: Pilots are specially certified for Cat II or III (very low visibility) approaches, this is true for autoland or Heads Up Display (HUD) approaches. They demonstrate proficiency during simulator training regularly.

Most of the modern jets that are capable of Cat II or III landings have pilots that are certified for this operation. Some of the smaller jets do not have this capability. I don't know the percentage for Cat III, sorry.

Q: Regarding last month's column, Patrick Smith, who writes the "Ask the Pilot" column for Salon, says that the tape in question is not duct tape of the type that is purchased at home improvement stores but is Speed Tape, an FAA-approved means of repair. He says that a 4-inch wide roll of Speed Tape can cost up to $7000.

— bobmrg

A: My answer was not as complete as it could have been. During my 25 years with the airline, I had never seen any type of tape used on a windshield. Several airplanes I took had recently had windshields replaced but there was no tape. Based on my experience I was skeptical. Several readers, including you, showed me that there are proper maintenance procedures -- one reader even provided a copy of the maintenance manual -- that use aluminum tape to protect the curing sealant of a recently changed windshield. I appreciate everyone who provided me with the better information.

To the previous reader's question regarding the RyanAir flight where tape was visible, please allow me to modify my answer: It is probable that they recently had changed the windshield and the tape was in place in accordance with the proper maintenance procedure. However, no, it is not a very common practice.

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John Cox is a retired airline captain with U.S. Airways and runs his own aviation safety consulting company, Safety Operating Systems.