Narrative:

The first officer (first officer) and I were on a visual approach on the last leg of a four-day trip; landing after midnight and over an hour late. While slowing and configuring for the approach as I moved the flaps to 5 the yaw damper kicked off and I noticed immediately that the flaps were not tracking. A visual check; gauge check; and leading edge lights check indicated no movement. At this time I took control of the aircraft to bring it back to 220 knots; level off and assess the problem. There were no additional indications of failure of any kind. It was unclear if the flap needle had moved at all. I then asked the first officer to break out the QRH. We [advised ATC] and asked for delay vectors away from terrain which also required a climb to 8000 feet. Upon inspection of the QRH; it was unclear to both of us which checklist we should be following. The first checklist listed is the all flaps up landing. This checklist; however; does not offer up a solution but points to another checklist; the trailing edge flaps up checklist; and does not direct you to a page. Returning to the index page you have the asymmetry which did not fit the situation and trailing edge flap disagree checklist that at the time; didn't seem right either. By this point we had already bored holes in the sky for ten minutes. I knew from training and experience that I should be looking to use the alternate flap switch. Looking to the trailing edge flaps up landing checklist I keyed in on the alternate flaps master switch statement and put the checklist down. The alternate flaps switch worked; and as a team; with the first officer flying; proceeded to move the flaps one setting at a time to make sure we had correct movement and no asymmetry. With successful movement to include lights and indicators and the fact that we were in VFR conditions I was satisfied with the result. I took back control of the aircraft from the first officer and told ATC that we were ready to land. From that point we proceeded to continue to configure and land with a flaps 30 landing. At the time I believe both of us were satisfied with the result; but both of us were frustrated with the amount of time and effort it took to figure out the solution.it was only after a discussion of the incident a few days later that I realized I had missed some key steps in the checklist and that I actually hadn't continued or finished the checklist. In the VFR conditions we had this solution seemed appropriate; but if the weather had been different or if I had lost an engine on final approach I would have caused myself some additional problems due to the position of the flaps at 30 for landing.my frustration with the QRH on this particular problem became clear to me which caused me to revert back on my knowledge of systems; but in my haste to solve the problem I also forgot some key concepts in using the checklist which I attribute to fatigue. The first officer on this flight was relatively new and therefore didn't have a lot experience to call on for this particular event; but was having the same problem I was; matching our indications to the proper checklist. I believe it would be helpful to rewrite the flap checklists into one checklist that then direct to follow-on checklists as you proceed through it. Also using page numbers would be helpful as opposed to just telling you to reference a title. In this particular malfunction the factors to consider and obvious solutions should be printed right up front rather than further down in the checklist as they would be the same for all of the different types of flap malfunctions.

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Original NASA ASRS Text

Title: B737NG flight crew reported experiencing Yaw Damper and Flap extension failures upon initial flap selection on approach. Crew reported confusion in attempting to decide which QRH procedure to use and offered recommended changes to the QRH.

Narrative: The First Officer (FO) and I were on a visual approach on the last leg of a four-day trip; landing after midnight and over an hour late. While slowing and configuring for the approach as I moved the flaps to 5 the yaw damper kicked off and I noticed immediately that the flaps were not tracking. A visual check; gauge check; and leading edge lights check indicated no movement. At this time I took control of the aircraft to bring it back to 220 knots; level off and assess the problem. There were no additional indications of failure of any kind. It was unclear if the flap needle had moved at all. I then asked the FO to break out the QRH. We [advised ATC] and asked for delay vectors away from terrain which also required a climb to 8000 feet. Upon inspection of the QRH; it was unclear to both of us which checklist we should be following. The first checklist listed is the All Flaps Up Landing. This checklist; however; does not offer up a solution but points to another checklist; the Trailing Edge Flaps Up Checklist; and does not direct you to a page. Returning to the index page you have the Asymmetry which did not fit the situation and Trailing Edge Flap Disagree checklist that at the time; didn't seem right either. By this point we had already bored holes in the sky for ten minutes. I knew from training and experience that I should be looking to use the alternate flap switch. Looking to the Trailing Edge Flaps UP Landing Checklist I keyed in on the Alternate Flaps Master switch statement and put the checklist down. The Alternate Flaps switch worked; and as a team; with the FO flying; proceeded to move the flaps one setting at a time to make sure we had correct movement and no asymmetry. With successful movement to include lights and indicators and the fact that we were in VFR conditions I was satisfied with the result. I took back control of the aircraft from the FO and told ATC that we were ready to land. From that point we proceeded to continue to configure and land with a flaps 30 landing. At the time I believe both of us were satisfied with the result; but both of us were frustrated with the amount of time and effort it took to figure out the solution.It was only after a discussion of the incident a few days later that I realized I had missed some key steps in the checklist and that I actually hadn't continued or finished the checklist. In the VFR conditions we had this solution seemed appropriate; but if the weather had been different or if I had lost an engine on final approach I would have caused myself some additional problems due to the position of the flaps at 30 for landing.My frustration with the QRH on this particular problem became clear to me which caused me to revert back on my knowledge of systems; but in my haste to solve the problem I also forgot some key concepts in using the checklist which I attribute to fatigue. The FO on this flight was relatively new and therefore didn't have a lot experience to call on for this particular event; but was having the same problem I was; matching our indications to the proper checklist. I believe it would be helpful to rewrite the flap checklists into one checklist that then direct to follow-on checklists as you proceed through it. Also using page numbers would be helpful as opposed to just telling you to reference a title. In this particular malfunction the factors to consider and obvious solutions should be printed right up front rather than further down in the checklist as they would be the same for all of the different types of flap malfunctions.

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.