Narrative:

Prior to departure; gate agents could not provide accurate passenger count due to integration related issues. I insisted that they provide a manual count with accurate souls on board (sob) count. (I explained that in case of an emergency; ATC will need an accurate sob count. This becomes important later!) in cruise; master caution illuminated with hydraulic on '6 pack.' verified number 2 engine driven hydraulic pump illuminated and zero fluid quantity in system B. Made decision to run QRH; declare emergency and divert to alternate airport. Captain was pilot not flying and performed QRH. He started running the loss of all hydraulics checklist and exacerbated problems. Autopilot failed as a result increasing my workload and I fortunately stopped him from completing wrong checklist. He started performing correct checklist while I flew aircraft; pulled up the divert airport ATIS; sent ACARS message to maintenance and dispatch and setup FMC for diversion. Once emergency was declared we were given priority handling and given vectors direct. I advised captain we should advise ATC we needed longest available runway. Captain was not assertive when communicating with ATC. I advised captain that I would like to configure aircraft early. Upon selection of flaps 1; system B electric pump failed due to low quality at stand pipe. We requested radar vectors off of localizer to perform manual flap extension checklist. Captain performed checklist. I requested that he not go beyond flaps 10 until we lowered the gear in order to prevent gear warning horn 35 miles out. He manually extended flaps beyond 10 and gear horn began continuously. I called gear down flaps 15 landing checklist and somewhere between flaps 10 and 15; the captain decided he wanted to land the aircraft. This left me to complete the checklist with no idea of where he left off or time to review what had been done up until that point. Even though I had been hand flying the aircraft for the preceding 30 minutes; a transfer of control took place. Pilot induced oscillations and dutch roll were extreme; but a safe landing was made. We taxied to the gate with emergency aircraft following and terminated the flight.

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Original NASA ASRS Text

Title: A B737-800 Master Caution Light and Master Warning HYD illuminated in cruise with the System B quantity indicating zero so the QRH was completed; an emergency declared and the flight diverted. CRM and crew coordination issues developed on final.

Narrative: Prior to departure; gate agents could not provide accurate passenger count due to integration related issues. I insisted that they provide a manual count with accurate Souls On Board (SOB) count. (I explained that in case of an emergency; ATC will need an accurate SOB count. This becomes important later!) In cruise; Master Caution illuminated with HYD on '6 pack.' Verified Number 2 Engine driven hydraulic pump illuminated and zero fluid quantity in System B. Made decision to run QRH; declare emergency and divert to alternate airport. Captain was pilot not flying and performed QRH. He started running the loss of all hydraulics checklist and exacerbated problems. Autopilot failed as a result increasing my workload and I fortunately stopped him from completing wrong checklist. He started performing correct checklist while I flew aircraft; pulled up the divert airport ATIS; sent ACARS message to Maintenance and Dispatch and setup FMC for diversion. Once emergency was declared we were given priority handling and given vectors direct. I advised Captain we should advise ATC we needed longest available runway. Captain was not assertive when communicating with ATC. I advised Captain that I would like to configure aircraft early. Upon selection of Flaps 1; System B Electric Pump failed due to low quality at stand pipe. We requested radar vectors off of localizer to perform manual flap extension checklist. Captain performed checklist. I requested that he not go beyond flaps 10 until we lowered the gear in order to prevent gear warning horn 35 miles out. He manually extended flaps beyond 10 and gear horn began continuously. I called gear down flaps 15 Landing Checklist and somewhere between flaps 10 and 15; the Captain decided he wanted to land the aircraft. This left me to complete the checklist with no idea of where he left off or time to review what had been done up until that point. Even though I had been hand flying the aircraft for the preceding 30 minutes; a transfer of control took place. Pilot induced oscillations and dutch roll were extreme; but a safe landing was made. We taxied to the gate with emergency aircraft following and terminated the flight.

Data retrieved from NASA's ASRS site as of July 2013 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.