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FMS/FMGS computers can fly many modern aircraft between waypoints set by the crew. They find their way using aids like IRS, GPS, DME, and ILS and are able to manage route, altitude and thrust.

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Mode control panel (MCP) on a B737 NG (probable source: Alessio Meneghetti on Flickr)

Most of a commercial flight can be handled by computers when everything goes as planned, air regulations don't seem to forbid such automation.

On the other hand the crew ensures flight safety, programs, engages and monitors computers, handles changes, hitches and abnormal situations, takes decisions and re-programs computers with new instructions. Some configuration changes (e.g. landing gears) are also beyond computer reach.

I'm curious to know which actions are manual and how much time is spent for them from entering the takeoff runway to leaving the landing runway, e.g. for a 2,500 NM commercial flight? What is the current trend for airlines policies regarding the use of these automation capabilities?

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  • $\begingroup$ Your heading asks about the aircraft being flown manually but the question asks about "important actions." Are you asking about hands on yoke or are you asking about actions required while ap is on? $\endgroup$ – TomMcW Apr 2 '16 at 22:24
  • $\begingroup$ @TomMcW: I've added an example in the question. I'm trying to understand which part of the flight is basically flown automatically (with some inputs from the crew), and which part is flown manually (and how much time this takes). $\endgroup$ – mins Apr 3 '16 at 0:13
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Today's aircraft automation is just not set up for unattended operation.

There are too many individual tasks, that pilots must complete, to list here. The lowest workload for pilots is during cruise but even then ATC can instruct you to change speed, routing, or altitudes. Maybe one day this could be controlled from the ground but today only the pilots can make those changes.

I think you want to know how many minutes of an average flight are the pilots actually manipulating the controls either manually or through the A/P.

The A/P comes on somewhere between 30 seconds and 7 mins after takeoff and it stays on continually for the whole flight until maybe 2 mins before touchdown.

Every flight is different and sometimes there is lots of vectoring by ATC on departure/arrival and lots of step climb/descents, which requires the crew to "fly" the A/P. Sometimes the arrival/departure are linked up directly with the en route portion and you get a direct climb/descent.

So as a rough guess on an average flight the pilots might manually fly the aircraft for about 3–10 minutes and "fly" the A/P for about 5–10 mins. The rest of the time is spent talking to ATC, doing checklists, checking weather, fuel checks, and trying to keep yourself busy any other way you can think of. :)

I personally fly mostly ultra long haul flights of 13–15 hours as part of a 4-man crew so I also spend about 6–7 hours sleeping in the bunk.

In every phase of flight the crew is needed to do much more than just monitor the automation. The automation can not be used unless the pilots first enter all the required parameters, and then activate the automation at the right time, and in the correct order.

There is no aircraft that can take off on autopilot. The autopilot can only be engaged after takeoff. Once airborne at cruising altitude the aircraft could follow a programmed flight routing but any change in heading, routing or altitude must be manually entered by the pilot.

At the destination the approach must be manually programmed for the approach and runway in use. Once the aircraft in on the ILS approach an aircraft with autoland capability can land itself but it still needs the pilots to clear the runway.

Autopilot/autothrottle policies can vary with each airline. Typically airline pilots hand fly from takeoff to at least 200' but many hand fly to 10,000' or more for practice. When landing most pilots hand fly from about 1,000'.

Depending on the specific aircraft, autothrottle is usually engaged during the the takeoff roll and stays on until the flare just as it lands. There is no automation for landing gear and flap operation. It is 100% manual.

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  • $\begingroup$ I added more info, but here are too many individual steps to list here. This similar question and answer has more info as well but still does not cover everything a pilot does in order to complete a flight. aviation.stackexchange.com/questions/2866/… $\endgroup$ – Mike Sowsun Apr 2 '16 at 18:33
  • $\begingroup$ I guess I still don't understand your question, or the point of your question. Today's aircraft can not be flown "automatically" without a pilot. What more do you want to know? $\endgroup$ – Mike Sowsun Apr 2 '16 at 18:47
  • $\begingroup$ I would like to have an estimate of the effort done by the crew, when using all automation allowed (or recommended) by the airline. For example: ... and during cruise, the A/P is engaged, from time to time the crew will allow a step climb (one per hour), this is a matter of turning a knob, and takes 20 seconds..... I guess it's not so simple, but it would allow to understand the A/P could pilot and navigate during several hours, with small interventions from the crew (if this is the case indeed). $\endgroup$ – mins Apr 2 '16 at 18:52
  • $\begingroup$ Generally all airline pilots use all the automation that is available to them. Those "small interventions" you mention require experience and decision making skills. Even just turning a knob or pressing a button to change an altitude has to be carefully considered because that change of altitude may not be safe, fuel efficient or comfortable. $\endgroup$ – Mike Sowsun Apr 2 '16 at 19:03
  • $\begingroup$ Indeed Mike, I agree 110%, but that's not my point in this question. $\endgroup$ – mins Apr 2 '16 at 19:11
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A paper from Duke University, Functional Requirements for Onboard Intelligent Automation in Single Pilot Operations, based on interviews with commercial airline pilots, states the following:

Pilots flying the 777 agreed that they spent about 7 minutes for a typical flight actually "flying" the aircraft, meaning touching the controls. The Airbus pilots stated they "flew" their aircraft about half that time.

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