Narrative:

Upon approach into atw the first officer called for flaps 10 degrees. I selected 10 degrees, but the flaps didn't move. I tried reselecting 10 degrees and still nothing. I checked the breaker; that was ok. Hydraulic pressure in the system was good, but both engine driven pumps read 0 psi. Main system pressure was approximately 1800 psi, yet not enough to actuate either the gear or flap systems. We flew a VFR pattern over atw at 2500' MSL and went through a manual gear extension procedure. Once 3 green lights were indicated, we overflew the tower for a visibility ok. After atx confirmed a visibility on our gear, we flew back to mke with 2.5 hours fuel remaining. The WX was VFR along the route and we accepted priority handling. We flew back to mke because they have better crash fire rescue and facs to handle disabled aircraft. Crash and rescue was called out at mke because of potential brake and nose steering limitations. We elected to land 0 degrees flap because once the flaps are manually selected, they cannot be retracted. Also in training a 0 degree flap landing was recommended in this situation. We rebriefed the passenger on the emergency procedures and landed 0 degree flap, gear down at mke west/O any further incident. All checklists and procedures were adhered to with strict discipline. In a final analysis, a nose wheel steering and line (hydraulic) ruptured spewing hydraulic fluid out the belly of the aircraft. Both engine driven pumps cavitated and had to be replaced. Fortunately the emergency side of the hydraulic system maintained fluid with made the safe gear down landing possible. Also the strict adherence to company procedures and checklists made this flight conclude safely.

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Original NASA ASRS Text

Title: COMMUTER LTT LOST ENGINE HYDRAULIC PUMP PRESSURE ENROUTE TO ATW. PROBLEM WAS DISCOVERED WHEN THE FLAPS WOULD NOT EXTEND NORMALLY. AFTER LOWERING THE GEAR THE ACFT RETURNED TO MKE FOR LNDG.

Narrative: UPON APCH INTO ATW THE F/O CALLED FOR FLAPS 10 DEGS. I SELECTED 10 DEGS, BUT THE FLAPS DIDN'T MOVE. I TRIED RESELECTING 10 DEGS AND STILL NOTHING. I CHKED THE BREAKER; THAT WAS OK. HYD PRESSURE IN THE SYS WAS GOOD, BUT BOTH ENG DRIVEN PUMPS READ 0 PSI. MAIN SYS PRESSURE WAS APPROX 1800 PSI, YET NOT ENOUGH TO ACTUATE EITHER THE GEAR OR FLAP SYSTEMS. WE FLEW A VFR PATTERN OVER ATW AT 2500' MSL AND WENT THROUGH A MANUAL GEAR EXTENSION PROC. ONCE 3 GREEN LIGHTS WERE INDICATED, WE OVERFLEW THE TWR FOR A VIS OK. AFTER ATX CONFIRMED A VIS ON OUR GEAR, WE FLEW BACK TO MKE WITH 2.5 HRS FUEL REMAINING. THE WX WAS VFR ALONG THE RTE AND WE ACCEPTED PRIORITY HANDLING. WE FLEW BACK TO MKE BECAUSE THEY HAVE BETTER CRASH FIRE RESCUE AND FACS TO HANDLE DISABLED ACFT. CRASH AND RESCUE WAS CALLED OUT AT MKE BECAUSE OF POTENTIAL BRAKE AND NOSE STEERING LIMITATIONS. WE ELECTED TO LAND 0 DEGS FLAP BECAUSE ONCE THE FLAPS ARE MANUALLY SELECTED, THEY CANNOT BE RETRACTED. ALSO IN TRNING A 0 DEG FLAP LNDG WAS RECOMMENDED IN THIS SITUATION. WE REBRIEFED THE PAX ON THE EMER PROCS AND LANDED 0 DEG FLAP, GEAR DOWN AT MKE W/O ANY FURTHER INCIDENT. ALL CHKLISTS AND PROCS WERE ADHERED TO WITH STRICT DISCIPLINE. IN A FINAL ANALYSIS, A NOSE WHEEL STEERING AND LINE (HYD) RUPTURED SPEWING HYD FLUID OUT THE BELLY OF THE ACFT. BOTH ENG DRIVEN PUMPS CAVITATED AND HAD TO BE REPLACED. FORTUNATELY THE EMER SIDE OF THE HYD SYS MAINTAINED FLUID WITH MADE THE SAFE GEAR DOWN LNDG POSSIBLE. ALSO THE STRICT ADHERENCE TO COMPANY PROCS AND CHKLISTS MADE THIS FLT CONCLUDE SAFELY.

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.