Narrative:

On climb out left side thrust reverser light came on in flight, i.e., the master warning hydraulic pressure on light and arm light. Went through the thrust reverser arm light on in-flight checklist as well as reviewed the thrust reverser inadvertent in-flight deployment and thrust reverser unlock light on in-flight. On approach into cmh, selected flaps 20 degree. Hydraulic low flow light illuminated. Declared an emergency. Completed hydraulic system remains on pressurized checklist. Completed landing gear emergency extension checklist. Landed without incident. I was very puzzled when selecting flaps to 20 degrees. The hydraulic low flow light illuminated. I felt there was a hydraulic leak somewhere. That is why I extended the landing gear with the emergency extension lever. Flaps held at 20 degrees. Upon landing, maintenance found the hydraulic reverser full.

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Original NASA ASRS Text

Title: EMER DECLARED ON APCH BY CPR JET WITH ACFT EQUIP PROB.

Narrative: ON CLBOUT L SIDE THRUST REVERSER LIGHT CAME ON IN FLT, I.E., THE MASTER WARNING HYD PRESSURE ON LIGHT AND ARM LIGHT. WENT THROUGH THE THRUST REVERSER ARM LIGHT ON INFLT CHKLIST AS WELL AS REVIEWED THE THRUST REVERSER INADVERTENT INFLT DEPLOYMENT AND THRUST REVERSER UNLOCK LIGHT ON INFLT. ON APCH INTO CMH, SELECTED FLAPS 20 DEG. HYD LOW FLOW LIGHT ILLUMINATED. DECLARED AN EMER. COMPLETED HYD SYS REMAINS ON PRESSURIZED CHKLIST. COMPLETED LNDG GEAR EMER EXTENSION CHKLIST. LANDED WITHOUT INCIDENT. I WAS VERY PUZZLED WHEN SELECTING FLAPS TO 20 DEGS. THE HYD LOW FLOW LIGHT ILLUMINATED. I FELT THERE WAS A HYD LEAK SOMEWHERE. THAT IS WHY I EXTENDED THE LNDG GEAR WITH THE EMER EXTENSION LEVER. FLAPS HELD AT 20 DEGS. UPON LNDG, MAINT FOUND THE HYD REVERSER FULL.

Data retrieved from NASA's ASRS site as of July 2007 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.