Narrative:

Taxiing out on aircraft X [I] noted to captain I felt some vibration in [the] yoke during the elevator check. Because of a similar instance on aircraft Y (where the aircraft was removed from service) I had seen this anomaly. In sequence; awaiting takeoff and stopped; he ran the elevator and found it to be normal. We assumed it was our light weight or a nose wheel shimmy that led to the vibration. Flew a manual departure until about 17;000 feet when ap (auto pilot) 2 was engaged. Turning final into ZZZ; outside the marker I turned the ap off; tried to roll out of the turn manually and noticed controls were very heavy/almost unresponsive. Turning in opposite direction the controls were equally heavy. Force required to turn was about three to four times heavier than normal. It felt as though the ap was still engaged or we were flying in manual reversion. Verified ap was off. Asked captain to try it and he agreed; noting a slight roll to right requiring left aileron to remain wings level and that the elevator was also very heavy. Captain elected to do the landing; used power to help control rate of descent and some rudder to augment roll (rudder was fine). Ap single land and no-autoland alerts observed 2 miles out. Captain elected to disregard these level one alerts and focus on flying the airplane. Asked me to back him up on controls. Discussed how we would perform a go-around and use the ap if necessary for a go-around if control became unmanageable. Glide slope was intermittent due to other aircraft on either side of the antenna on the ground (so use of ap was inappropriate for this landing). Small inputs by captain were difficult; but deliberate and perfect. Landing was within normal parameters. We agreed to leave aircraft configured as it was to the blocks. Maintenance met us and ran the controls on rmp's. Thankfully; the problem persisted so they were able to witness the same difficulty moving the yoke. In the half hour we spent writing this up; I overheard the maintenance supervisor leaning towards swapping the FCC's (flight control computers) as a fix. Thankfully; the line mechanics insisted ap was red for at least 12 hours and pushed to dig further into it. They eventually found a faulty actuator in the right wing. This is as much as I know about the current situation on aircraft X. Thankfully; the weather was VFR; with 8 kts down the runway. Gusty winds or high crosswinds would have made it extremely difficult (if not impossible) to land this airplane safely. Submitting this [report] due to the grave nature of this flight control malfunction; which could have resulted in a hull loss or fatalities under other circumstances.explanation of recommendations: this same anomaly has occurred at least three times in the past six months at our company after disconnecting the ap on approach: the previous flight of aircraft X two days earlier; our flight on this same aircraft X; and on aircraft Z a few months ago. There was also an incident last winter on aircraft a in ZZZ1; which nearly resulted in the loss of the airplane due to the crew's inability to control excessive up/down pitch forces. Aircraft Y was removed from service for strong vibrations that shook the entire airplane during the elevator check (my flight). Two recommendations/notifications have been generated over the past 6 months regarding these events. These notifications emphasized the use of the jammed or restricted flight control checklist in the aom. Unfortunately; these notifications appear to be more legal posturing rather than a serious; proactive effort to address what seems to be a systemic problem. Despite these (known) incidents; I have been told by company management and safety representatives that a fleet-wide inspection is unwarranted/unnecessary. If this is true and recommendations/notifications are favorable to an in-depth inspection of all company MD11's prior to heavy checks; I suggest the following procedures be implemented immediately.recommend control check be performed at flap extension; prior to aircraft movement. As a considerably 'long' airplane; any anomalies in the flight control check would be/are difficult to detect during taxi; due to bouncing of aircraft on taxi. If a manual landing is planned; recommend disconnection of ap above 3;000 feet AGL; prior to approach; and re-engagement later; if desired. While a briefing on the use of automation is already required by fom; this would allow crews the time (and altitude) to discover controllability problems prior to being committed to land or to doing an unwanted go-around with limited/partial control. Part of our decision to continue was not wanting to be 25 degrees nose high; light-weight at full power; with limited lateral/longitudinal control.aircraft X had been written up two days earlier for the same malfunction. In this case; the previous crew wrote that the ailerons 'were stiff and unresponsive' and elected to do an auto-land instead of a manual landing. Having flown the MD11 for several years I can tell you that doing an auto-land with a single ap (because manual controls aren't working) is a last resort. Recommend mandatory review of aircraft history for flight control issues as a first course of action prior to troubleshooting. In our case; this did not happen and maintenance began troubleshooting prior to reviewing the history.recommend the fdr/cfds (flight data recorder/centralized fault and display system) and all other available reporting systems be reviewed on our flight to determine the position of the ap clutches; control wheel deflections; control wheel forces; control surface positions; etc.; to rule out partial ap engagement after ap disengagement.

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Original NASA ASRS Text

Title: MD-11 flight crew reported heavy/unresponsive flight controls during approach to landing. Flight crew stated this is a recurring issue on the MD-11 aircraft fleet.

Narrative: Taxiing out on Aircraft X [I] noted to Captain I felt some vibration in [the] yoke during the elevator check. Because of a similar instance on Aircraft Y (where the aircraft was removed from service) I had seen this anomaly. In sequence; awaiting takeoff and stopped; he ran the elevator and found it to be normal. We assumed it was our light weight or a nose wheel shimmy that led to the vibration. Flew a manual departure until about 17;000 feet when AP (Auto Pilot) 2 was engaged. Turning final into ZZZ; outside the marker I turned the AP off; tried to roll out of the turn manually and noticed controls were very heavy/almost unresponsive. Turning in opposite direction the controls were equally heavy. Force required to turn was about three to four times heavier than normal. It felt as though the AP was still engaged or we were flying in manual reversion. Verified AP was off. Asked Captain to try it and he agreed; noting a slight roll to right requiring left aileron to remain wings level and that the elevator was also very heavy. Captain elected to do the landing; used power to help control rate of descent and some rudder to augment roll (rudder was fine). AP Single Land and No-Autoland alerts observed 2 miles out. Captain elected to disregard these level one alerts and focus on flying the airplane. Asked me to back him up on controls. Discussed how we would perform a go-around and use the AP if necessary for a go-around if control became unmanageable. Glide slope was intermittent due to other Aircraft on either side of the antenna on the ground (so use of AP was inappropriate for this landing). Small inputs by Captain were difficult; but deliberate and perfect. Landing was within normal parameters. We agreed to leave aircraft configured as it was to the blocks. Maintenance met us and ran the controls on RMP's. Thankfully; the problem persisted so they were able to witness the same difficulty moving the yoke. In the half hour we spent writing this up; I overheard the Maintenance Supervisor leaning towards swapping the FCC's (Flight Control Computers) as a fix. Thankfully; the line mechanics insisted AP was red for at least 12 hours and pushed to dig further into it. They eventually found a faulty actuator in the right wing. This is as much as I know about the current situation on Aircraft X. Thankfully; the weather was VFR; with 8 kts down the runway. Gusty winds or high crosswinds would have made it extremely difficult (if not impossible) to land this airplane safely. Submitting this [report] due to the grave nature of this flight control malfunction; which could have resulted in a hull loss or fatalities under other circumstances.Explanation of recommendations: This same anomaly has occurred at least three times in the past six months at our company after disconnecting the AP on approach: the previous flight of Aircraft X two days earlier; our flight on this same Aircraft X; and on Aircraft Z a few months ago. There was also an incident last winter on Aircraft A in ZZZ1; which nearly resulted in the loss of the airplane due to the crew's inability to control excessive up/down pitch forces. Aircraft Y was removed from service for strong vibrations that shook the entire airplane during the elevator check (my flight). Two recommendations/notifications have been generated over the past 6 months regarding these events. These notifications emphasized the use of the Jammed or Restricted Flight Control Checklist in the AOM. Unfortunately; these notifications appear to be more legal posturing rather than a serious; proactive effort to address what seems to be a systemic problem. Despite these (known) incidents; I have been told by company management and safety representatives that a fleet-wide inspection is unwarranted/unnecessary. If this is true and recommendations/notifications are favorable to an in-depth inspection of all company MD11's prior to heavy checks; I suggest the following procedures be implemented immediately.Recommend Control Check be performed at flap extension; prior to aircraft movement. As a considerably 'long' airplane; any anomalies in the flight control check would be/are difficult to detect during taxi; due to bouncing of aircraft on taxi. If a manual landing is planned; recommend disconnection of AP above 3;000 feet AGL; prior to approach; and re-engagement later; if desired. While a briefing on the use of automation is already required by FOM; this would allow crews the time (and altitude) to discover controllability problems prior to being committed to land or to doing an unwanted go-around with limited/partial control. Part of our decision to continue was not wanting to be 25 degrees nose high; light-weight at full power; with limited lateral/longitudinal control.Aircraft X had been written up two days earlier for the same malfunction. In this case; the previous crew wrote that the ailerons 'were stiff and unresponsive' and elected to do an Auto-Land instead of a manual landing. Having flown the MD11 for several years I can tell you that doing an auto-land with a single AP (because manual controls aren't working) is a last resort. Recommend mandatory review of aircraft history for flight control issues as a first course of action prior to troubleshooting. In our case; this did not happen and Maintenance began troubleshooting prior to reviewing the history.Recommend the FDR/CFDS (Flight Data Recorder/Centralized Fault And Display System) and all other available reporting systems be reviewed on our flight to determine the position of the AP clutches; control wheel deflections; control wheel forces; control surface positions; etc.; to rule out partial AP engagement after AP disengagement.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.