Slow hydraulic system loss.

Attributes
ACN	310078
Time
Date	199507
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : stp
State Reference	MN
Altitude	agl bound lower : 0 agl bound upper : 1800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : stp
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 135
Flight Phase	descent : approach landing other
Route In Use	approach : straight in
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 2500 flight time type : 800
ASRS Report	310078
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : overcame equipment problem other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Approximately 12 NM out of stp, while turning onto the ILS, the captain noticed both hydraulic warning lights starting to illuminate. The hydraulic shutoff valves were open, so I immediately started slowing the aircraft to configure for landing. We selected 1/4 flaps, then 1/2 flaps, then lowered the landing gear. Landing gear came down '3 green' but took a considerable amount of time to do so. We then selected the abnormal/emergency checklist to confirm our actions. At this point the hydraulic pressure was 1200 psi, therefore not enough fluid for a full flap landing. The aircraft landed uneventfully with 1/2 flaps. Upon clearing the runway, the captain took control of the aircraft. Due to the hydraulic failure, we did not have nosewheel steering capability and had to be towed to the gate. There were no injuries to the passenger or crew nor was there any damage to the aircraft, other than the hydraulic problem itself.

Original NASA ASRS Text

Title: SLOW HYD SYS LOSS.

Narrative: APPROX 12 NM OUT OF STP, WHILE TURNING ONTO THE ILS, THE CAPT NOTICED BOTH HYD WARNING LIGHTS STARTING TO ILLUMINATE. THE HYD SHUTOFF VALVES WERE OPEN, SO I IMMEDIATELY STARTED SLOWING THE ACFT TO CONFIGURE FOR LNDG. WE SELECTED 1/4 FLAPS, THEN 1/2 FLAPS, THEN LOWERED THE LNDG GEAR. LNDG GEAR CAME DOWN '3 GREEN' BUT TOOK A CONSIDERABLE AMOUNT OF TIME TO DO SO. WE THEN SELECTED THE ABNORMAL/EMER CHKLIST TO CONFIRM OUR ACTIONS. AT THIS POINT THE HYD PRESSURE WAS 1200 PSI, THEREFORE NOT ENOUGH FLUID FOR A FULL FLAP LNDG. THE ACFT LANDED UNEVENTFULLY WITH 1/2 FLAPS. UPON CLRING THE RWY, THE CAPT TOOK CTL OF THE ACFT. DUE TO THE HYD FAILURE, WE DID NOT HAVE NOSEWHEEL STEERING CAPABILITY AND HAD TO BE TOWED TO THE GATE. THERE WERE NO INJURIES TO THE PAX OR CREW NOR WAS THERE ANY DAMAGE TO THE ACFT, OTHER THAN THE HYD PROB ITSELF.

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.