Narrative:

About 35 minutes out the #2 hydraulic isolation valve caution light came on. We started to run the checklist which is combined with the #2 engine hydraulic pump caution checklist. After directing us to push in the ptu the checklist asks if the #2 pressure is normal; which it is; answer yes - no further crew action required. The quantity was 10%. Maintenance was contacted and we were told that they would meet us after landing. We started to think through the system and realized that the direction of 'no further crew action required' seemed odd since with the #2 hydraulic isolation valve closed we would not be able to operate the gear normally; also losing steering etc. The checklist directed us to monitor several things including the system pressure and fluid quantity. After two boxes of notes there were some 'if' statements which included 'if the #2 hydraulic isolation valve caution illuminates (the checklist heading and caution light that started this) continue the checklist'. If this is the case why did it say no further crew action required? We felt confident that a manual gear extension was going to be required and started to plan for the eventuality. We tried to contact maintenance again but had no luck. Finally 10 miles out we were able to get a hold of them again and ask about the ambiguity in the checklist; they were also confused. We anticipated the manual gear extension but did not go to the alt gear extension checklist because the #2 hydraulic isolation valve checklist said no further crew action required. We had a jumpseater and asked him what he thought of how the checklist read; he was just as confused by the sequence of the checklist. We requested a 10 mile final for a visual landing. When we were at 10;000 MSL on downwind we tried to lower the gear; nothing as expected. We then declared an emergency with approach went back and finished the #2 hydraulic isolation valve checklist and then accomplished the alt gear extension checklist as directed. The controls were transferred to the captain and a normal landing was made. We were able to taxi in with differential power and braking. This was also a point of confusion between the #2 hydraulic isolation valve and alt gear extension checklists; one said clear the runway; shutdown; put the gear pins in; and get towed to the gate; the other checklist said to taxi to the gate if able and then put the gear pins in. The captain filled out the maintenance logbook and talked with the mechanic; he was then asked to call crew scheduling. When he did so they transferred him to the flight control manager who proceeded to yell at him for not calling dispatch and threatened us by going to our supervisors. The crew worked very well together; including the jumpseater. Resources were utilized (when we could get a hold of operations) and events anticipated to ease task saturation during a high workload environment despite a poorly designed checklist.

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Original NASA ASRS Text

Title: Q400 First Officer describes a #2 HYD ISO VLV caution light in flight leading to a poorly written checklist designed to deal with it. Flight lands after manual gear extension and taxis to the gate using differential thrust and brakes.

Narrative: About 35 minutes out the #2 Hydraulic Isolation Valve Caution light came on. We started to run the checklist which is combined with the #2 Engine Hydraulic Pump Caution Checklist. After directing us to push in the PTU the checklist asks if the #2 pressure is normal; which it is; answer YES - No further crew action required. The quantity was 10%. Maintenance was contacted and we were told that they would meet us after landing. We started to think through the system and realized that the direction of 'No further crew action required' seemed odd since with the #2 Hydraulic Isolation Valve closed we would not be able to operate the gear normally; also losing steering etc. The checklist directed us to monitor several things including the system pressure and fluid quantity. After two boxes of notes there were some 'IF' statements which included 'If the #2 Hydraulic Isolation Valve caution illuminates (the checklist heading and caution light that started this) continue the checklist'. If this is the case why did it say no further crew action required? We felt confident that a manual gear extension was going to be required and started to plan for the eventuality. We tried to contact Maintenance again but had no luck. Finally 10 miles out we were able to get a hold of them again and ask about the ambiguity in the checklist; they were also confused. We anticipated the manual gear extension but did not go to the Alt Gear Extension Checklist because the #2 Hydraulic Isolation Valve Checklist said no further crew action required. We had a jumpseater and asked him what he thought of how the checklist read; he was just as confused by the sequence of the checklist. We requested a 10 mile final for a visual landing. When we were at 10;000 MSL on downwind we tried to lower the gear; nothing as expected. We then declared an emergency with Approach went back and finished the #2 Hydraulic Isolation Valve Checklist and then accomplished the Alt Gear Extension Checklist as directed. The controls were transferred to the Captain and a normal landing was made. We were able to taxi in with differential power and braking. This was also a point of confusion between the #2 Hydraulic Isolation Valve and Alt Gear Extension checklists; one said clear the runway; shutdown; put the gear pins in; and get towed to the gate; the other checklist said to taxi to the gate if able and then put the gear pins in. The Captain filled out the maintenance logbook and talked with the mechanic; he was then asked to call Crew Scheduling. When he did so they transferred him to the Flight Control Manager who proceeded to yell at him for not calling Dispatch and threatened us by going to our supervisors. The crew worked very well together; including the jumpseater. Resources were utilized (when we could get a hold of operations) and events anticipated to ease task saturation during a high workload environment despite a poorly designed checklist.

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.