Ask the Captain: When do pilots use manual controls?
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Question: What if the computers that help the pilot fly the plane get a virus or break down somehow? Can you fly without them? Computer glitches and technical problems can certainly happen at the worst times on the ground, so I imagine this can also be an issue in the air. Thank you!

— submitted by reader cydonia

Answer: Pilots can always fly the airplane manually. While we normally use satellite navigation, we can revert to ground base navigation easily. The flight control computers are very carefully screened to ensure that the software is stable. Some fly by wire airplanes use two different operating systems (like a PC and a Mac) on different computers to ensure redundancy. While occasional computer problems will arise, the crews know how to work around them or revert to manual. This is one of the reasons that pilots maintain manual flying skills.

Q: What are the quotas for manual landings, i.e. how many must be performed monthly or per cycle? What are the quotas for autolands? Are you limited to the amount you are allowed to perform? I imagine autoland is more precise, less wear-and-tear and above all safer than a manual landing.


A: The exact requirements for manual landing vary from airline to airline. It is important that pilots maintain manual flying skills. This is because there are situations in which autopilots are not as good as humans. Examples include some visual approaches, some circling approaches and some steep approaches.

One of the challenges facing the aviation industry today is maintain the right balance between maximizing automation and keeping manual flying skill polished.

Autolands are very good in low visibility conditions. However, in gusty crosswinds humans execute better landings.

I would not say one is safer than the other. Fortunately, we can use automated landing or manual landing as conditions require, we have best of both.

Q: When a thunderstorm pops up quickly right in flight path, how quickly can ATC and pilots react? Who decides what?


A: All decisions regarding the flight path of the airplane are up to the Captain. He or she has the best information to make the timely decisions. With weather radar on board, the pilots have the most up to date information. ATC will accommodate pilot requests for rerouting due to weather. Often this will be a request to deviate "X miles left or right of course to avoid weather." The ATC specialist adapts his or her traffic flow accordingly. The combined efforts of the pilots and the controllers make avoiding fast-building thunderstorms a routine event.

Q: I fly frequently from my home in Florida to Reagan National Airport (DCA). Although I spent most of my life in DC, it's still inspiring to see the city from the air. That river approach is a zig-zag that separates the pilots from the weekenders. I once had a "go round" no more than 50 ft off the runway when the wind direction suddenly changed. I also landed there in the dark with a very very low ceiling so you couldn't see the tops of some tall buildings. Makes one appreciate the skill in the cockpit and preciseness of the electronics.


A: The river approach is a visual maneuver which requires good speed control and precise alignment. There is restricted airspace to the left and buildings to the right. Add a gusty crosswind and low altitude maneuvering and you have all the ingredients of a piloting challenging. It is very satisfying to do it well.


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