Narrative:

This report is submitted to address a potentially serious safety concern associated with new flight profiles for the CE560 citation ultra. The specific profiles in question are: 1. The citation 500 series non-precision or LNAV approach - all engines and 2. The citation 500 series circling approach - all engines. The concern is common to both procedures - namely the extension of flaps to 35 degrees when 'course inbound (recommended 2-3 nm from the final approach fix (FAF)'. This procedure should be amended to the former method of maintaining flaps at the 15 degree position until the pilot flying calls for flap extension when leaving the MDA for the purpose of landing the aircraft. The new flaps 35 degree procedure; as it stands; significantly reduces the margin of safety while flying in proximity to terrain during the final portion of each approach prior to 'leaving the MDA' and is especially critical during the maneuvering portion of the circling approach.prudent practice suggests that a circling approach should be made in the maximum takeoff flap configuration and with good reason. In the event of a power plant failure; a go around can be accomplished quickly and safely by simply adding power. Selecting flaps 35 for the circling maneuver requires significant increased crew coordination in an extremely critical phase of flight. One only needs to consider a fatigued crew at the end of a long day flying into a remote airport at dusk or night and the only available approach is a circling approach.by contrast and comparison; the profiles have not been changed to reflect selecting flaps 35 degrees while in the downwind at 1;500 ft AGL for a 'visual traffic pattern.' the flaps are maintained in the 'lowest takeoff configuration' in the traffic pattern for the purpose of assuring proper safe aircraft performance in the event of power plant failure and this is happening at a much safer (1;500 ft AGL) altitude; yet we are now expecting crews to reduce their margin for error in the flaps 35 configuration at altitudes between 500 and 700 ft AGL. Why? How does this change improve operational aircraft safety or efficiency or crew resource management safety?flap selection at intermediate extensions is intended to improve lifting capability and is of primary importance in critical operations (takeoff and approach). Small initial deflection of the flaps cause noticeable positive changes in the maximum coefficient of lift without large changes in the drag coefficient; thus improving aircraft performance with minimal penalty to the safety margin. Large flap deflections past 30 degrees to 35 degrees do not create the same positive rate of change in the coefficient of lift but do cause greater changes in the coefficient of drag. A fact true of most airplanes is that the first 50 percent of flap deflection causes a more than half of the total change in the maximum coefficient of lift and the last 50 percent of flap deflection causes more than half the total change in the coefficient of drag. Flaps in the 35 degree position are a ground speed reduction device for landing rollout and provide little if any positive lifting performance for maneuvering at critical phases of flight. Additionally; having flown this procedure in the simulator during my week of training; I observed that the maneuver requires significant power to achieve level flight (75 to 85% N1) further reducing the margin of available power to perform the required go around in the event of an engine failure. Even if a perfect crew performed perfectly; there is a significant delay getting the flaps into a proper flaps 15 degree configuration for a single engine go around. Aerodynamics experts have told us that at relatively lower power settings at the maximum coefficient of lift; only negligible changes in stall speed will result since less aerodynamic lift is required to maintain stable flight. On the other hand; if thrust is very great and the aircraft experiences greater changes in pitch the effect on stall speed can be very great. This reduction in stall margin along with the potential for greater coordination in the event of a single engine on a circling approach (or straight in non-precision approach at MDA) is not a very comforting thought.I was informed that the reason for this change was to improve standardization among fleets. My interpretation of that is that the training department is striving for one document to cover all aircraft types. Other aircraft may have the performance to safely complete these maneuvers; but I do not hold that 'one size fits all' when it comes to the ultra. Given my experience flying in the CE560; I'm not convinced that the ultra has sufficiently safe engine performance to operate using this new procedure. Regardless of the aircraft type; I would ask; what is a proper safe margin for 'any' aircraft to maneuver in the landing flap configuration on a circling or non-precision straight in approach at the MDA? Consider; also; the crew coordination implications of having to perform these maneuvers with an engine failure and an MEL'd autopilot. I believe there is no benefit to operational safety and efficiency by changing to these new procedures; and on its face it would appear that these changes have been made for training convenience and expediency. If so; I submit; that is the wrong reason to change a proven; safe and effective procedure.there is some rumor and speculation circulating that these changes were enacted because some pilots may be having difficulty performing the circle to land procedure in the simulator during semi-annual company recurrent. Circling approaches are very demanding maneuvers and we operate far more frequently in this environment than our part 121 commercial counterparts; yet we spend far less time training for these likely events than for the single engine missed; or single engine ILS. I believe that is a serious shortcoming in our annual/semi annual training.one suggestion for improvement is to go immediately to a circling approach and landing after accomplishing the 'get acquainted' take offs; ILS approaches; and V1 cuts on day one of the recurrent simulator session before climbing up to 5;000 ft for steep turns and stall series; as a means to allow pilots to brush up on basic air work before having to perform the maneuver in the check ride. Using a circling maneuver at the completion of a GPS approach would also improve efficiency of the training event since pilots are routinely flying GPS approaches in the fleet prior to arriving at the sim. Performing the GPS and circling approach will help the pilot get acquainted with the peculiarities of the simulator FMS which performs a little different at times than those found in the fleet. If pilots are having difficulty with the circling maneuver in the check ride; these changes may be a benefit.

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Original NASA ASRS Text

Title: A CE-560 Captain questions modifications to company approach profiles which require the use of landing flaps from outside of the FAF on non-precision approaches.

Narrative: This report is submitted to address a potentially serious safety concern associated with new flight profiles for the CE560 Citation Ultra. The specific profiles in question are: 1. The Citation 500 Series Non-Precision or LNAV Approach - All Engines and 2. The Citation 500 Series circling Approach - All Engines. The concern is common to both procedures - namely the extension of flaps to 35 degrees when 'Course Inbound (Recommended 2-3 nm from the Final Approach Fix (FAF)'. This procedure should be amended to the former method of maintaining flaps at the 15 degree position until the pilot flying calls for flap extension when leaving the MDA for the purpose of landing the aircraft. The new Flaps 35 degree procedure; as it stands; significantly reduces the margin of safety while flying in proximity to terrain during the final portion of each approach prior to 'leaving the MDA' and is especially critical during the maneuvering portion of the circling approach.Prudent practice suggests that a circling approach should be made in the maximum takeoff flap configuration and with good reason. In the event of a power plant failure; a go around can be accomplished quickly and safely by simply adding power. Selecting Flaps 35 for the circling maneuver requires significant increased crew coordination in an extremely critical phase of flight. One only needs to consider a fatigued crew at the end of a long day flying into a remote airport at dusk or night and the only available approach is a circling approach.By contrast and comparison; the profiles have not been changed to reflect selecting Flaps 35 degrees while in the downwind at 1;500 FT AGL for a 'visual traffic pattern.' The flaps are maintained in the 'lowest takeoff configuration' in the traffic pattern for the purpose of assuring proper safe aircraft performance in the event of power plant failure and this is happening at a much safer (1;500 FT AGL) altitude; yet we are now expecting crews to reduce their margin for error in the flaps 35 configuration at altitudes between 500 and 700 FT AGL. Why? How does this change improve operational aircraft safety or efficiency or crew resource management safety?Flap selection at intermediate extensions is intended to improve lifting capability and is of primary importance in critical operations (takeoff and approach). Small initial deflection of the flaps cause noticeable positive changes in the maximum coefficient of lift without large changes in the drag coefficient; thus improving aircraft performance with minimal penalty to the safety margin. Large flap deflections past 30 degrees to 35 degrees do not create the same positive rate of change in the coefficient of lift but do cause greater changes in the coefficient of drag. A fact true of most airplanes is that the first 50 percent of flap deflection causes a MORE than half of the total change in the maximum coefficient of lift and the last 50 percent of flap deflection causes MORE than half the total change in the coefficient of drag. Flaps in the 35 degree position are a ground speed reduction device for landing rollout and provide little if any positive lifting performance for maneuvering at critical phases of flight. Additionally; having flown this procedure in the simulator during my week of training; I observed that the maneuver requires significant power to achieve level flight (75 to 85% N1) further reducing the margin of available power to perform the required go around in the event of an engine failure. Even if a perfect crew performed perfectly; there is a significant delay getting the flaps into a proper Flaps 15 degree configuration for a single engine go around. Aerodynamics experts have told us that at RELATIVELY lower power settings at the maximum coefficient of lift; only negligible changes in stall speed will result since less aerodynamic lift is required to maintain stable flight. On the other hand; if thrust is very great and the aircraft experiences greater changes in pitch the effect on stall speed can be very great. This reduction in stall margin along with the potential for greater coordination in the event of a single engine on a circling approach (or straight in non-precision approach at MDA) is not a very comforting thought.I was informed that the reason for this change was to improve standardization among fleets. My interpretation of that is that the Training Department is striving for one document to cover all aircraft types. Other aircraft may have the performance to safely complete these maneuvers; but I do not hold that 'one size fits all' when it comes to the ULTRA. Given my experience flying in the CE560; I'm not convinced that the ULTRA has sufficiently safe engine performance to operate using this new procedure. Regardless of the aircraft type; I would ask; what is a proper safe margin for 'any' aircraft to maneuver in the landing flap configuration on a circling or non-precision straight in approach at the MDA? Consider; also; the crew coordination implications of having to perform these maneuvers with an engine failure AND an MEL'd autopilot. I believe there is no benefit to operational safety and efficiency by changing to these new procedures; and on its face it would appear that these changes have been made for training convenience and expediency. If so; I submit; that is the wrong reason to change a proven; safe and effective procedure.There is some rumor and speculation circulating that these changes were enacted because some pilots may be having difficulty performing the circle to land procedure in the simulator during semi-annual company recurrent. Circling approaches are very demanding maneuvers and we operate far more frequently in this environment than our Part 121 commercial counterparts; yet we spend far less time training for these likely events than for the single engine missed; or single engine ILS. I believe that is a serious shortcoming in our annual/semi annual training.One suggestion for improvement is to go immediately to a circling approach and landing after accomplishing the 'get acquainted' take offs; ILS approaches; and V1 cuts on day one of the recurrent simulator session BEFORE climbing up to 5;000 FT for steep turns and stall series; as a means to allow pilots to brush up on basic air work before having to perform the maneuver in the check ride. Using a circling maneuver at the completion of a GPS approach would also improve efficiency of the training event since pilots are routinely flying GPS approaches in the fleet prior to arriving at the Sim. Performing the GPS and Circling approach will help the pilot get acquainted with the peculiarities of the simulator FMS which performs a little different at times than those found in the fleet. If pilots are having difficulty with the circling maneuver in the check ride; these changes may be a benefit.

Data retrieved from NASA's ASRS site as of April 2012 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.