An ATR42 on descent at 3000 ft lost the main hydraulic system pressure and quantity due to a flexibl...

Attributes
ACN	392567
Time
Date	199801
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : dak
State Reference	AR
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : fyv tower : fyv tower : cle
Operator	common carrier : air carrier
Make Model Name	ATR 42
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : cfi pilot : atp pilot : instrument
Experience	flight time last 90 days : 155 flight time total : 3200 flight time type : 619
ASRS Report	392567
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

On part 121 flight from stl to fyv. Approximately 15-20 mi north of fyv, the green hydraulic system (landing gear and normal braking) suffered a leak which caused the system low pressure and fluid low level alerts to activate. Shortly after the alerts, razorback approach cleared us for a visual approach into fyv and handed us over to tower at fyv. Fyv tower immediately cleared us to land on runway 16. At this time we were only 7-8 mi from fyv and still needed to execute checklists for the hydraulic failure, notify the flight attendants of the malfunction and prepare the aircraft for landing. We informed fyv tower that we needed more time and asked to enter an extended left pattern for runway 16. As we overflew the airport, the captain handed me the controls while he briefed the crew. As we proceeded northbound we requested to be handed off the razorback approach to receive vectors for another visual approach at fyv. We finished checklists, performance calculations for landing without normal braking and gear down missed approach and manually extended the landing gear. We conducted a normal approach and landing runway 16 at fyv. Callback conversation with reporter revealed the following information: the reporter stated the hydraulic system loss was caused by a chaffed metal braided flexible hydraulic line located in the access bay left landing gear fairing. The reporter said the blue hydraulic system was ok and did have flight controls but no nose steering or normal brakes.

Original NASA ASRS Text

Title: AN ATR42 ON DSCNT AT 3000 FT LOST THE MAIN HYD SYS PRESSURE AND QUANTITY DUE TO A FLEXIBLE METAL BRAIDED LINE FAILURE. CREW PERFORMED CHKLISTS, BRIEFED THE PAX AND LANDED UNEVENTFULLY.

Narrative: ON PART 121 FLT FROM STL TO FYV. APPROX 15-20 MI N OF FYV, THE GREEN HYD SYS (LNDG GEAR AND NORMAL BRAKING) SUFFERED A LEAK WHICH CAUSED THE SYS LOW PRESSURE AND FLUID LOW LEVEL ALERTS TO ACTIVATE. SHORTLY AFTER THE ALERTS, RAZORBACK APCH CLRED US FOR A VISUAL APCH INTO FYV AND HANDED US OVER TO TWR AT FYV. FYV TWR IMMEDIATELY CLRED US TO LAND ON RWY 16. AT THIS TIME WE WERE ONLY 7-8 MI FROM FYV AND STILL NEEDED TO EXECUTE CHKLISTS FOR THE HYD FAILURE, NOTIFY THE FLT ATTENDANTS OF THE MALFUNCTION AND PREPARE THE ACFT FOR LNDG. WE INFORMED FYV TWR THAT WE NEEDED MORE TIME AND ASKED TO ENTER AN EXTENDED L PATTERN FOR RWY 16. AS WE OVERFLEW THE ARPT, THE CAPT HANDED ME THE CTLS WHILE HE BRIEFED THE CREW. AS WE PROCEEDED NBOUND WE REQUESTED TO BE HANDED OFF THE RAZORBACK APCH TO RECEIVE VECTORS FOR ANOTHER VISUAL APCH AT FYV. WE FINISHED CHKLISTS, PERFORMANCE CALCULATIONS FOR LNDG WITHOUT NORMAL BRAKING AND GEAR DOWN MISSED APCH AND MANUALLY EXTENDED THE LNDG GEAR. WE CONDUCTED A NORMAL APCH AND LNDG RWY 16 AT FYV. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE HYD SYS LOSS WAS CAUSED BY A CHAFFED METAL BRAIDED FLEXIBLE HYD LINE LOCATED IN THE ACCESS BAY L LNDG GEAR FAIRING. THE RPTR SAID THE BLUE HYD SYS WAS OK AND DID HAVE FLT CTLS BUT NO NOSE STEERING OR NORMAL BRAKES.

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.

An ATR42 on descent at 3000 ft lost the main hydraulic system pressure and quantity due to a flexible metal braided line failure. Crew performed checklists, briefed the passenger and landed uneventfully.