A B737 flight crew experienced loss of 'a' system hydraulic quantity and pressure immediately after ...

Attributes
ACN	731480
Time
Date	200703
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 3500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : zzz.tracon
Operator	common carrier : air carrier
Make Model Name	B737-400
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	731480
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : eicas
Resolutory Action	flight crew : declared emergency flight crew : landed in emergency condition other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Within moments after retracting the landing gear during a normal takeoff on runway 1L in ZZZ; we received a master caution for low pressure lights in both system a hydraulic pumps and associated system a flight control low pressure light and feel 'diff' low pressure light. We noted that the system a hydraulic quantity had dropped to 3%. After assessing the situation and agreeing we had a total system a hydraulic failure; we commenced the QRH; declared an emergency with departure and arranged with dispatch a return to ZZZ. Flight attendants and passenger were briefed to expect a normal landing. Manual gear extension worked as advertised and the landing was uneventful. After landing; fire rescue crews noticed some steam vapor from the right main gear. Infrared temperature sensor revealed normal landing brake temperature and the steam was due to hydraulic fluid that had spilled onto brake assembly. Fire rescue said it would be safe to taxi to the gate. Turning into the gate our alternate nosewheel steering failed (system B quantity now at 61%). We were then towed into the gate.

Original NASA ASRS Text

Title: A B737 FLT CREW EXPERIENCED LOSS OF 'A' SYS HYD QUANTITY AND PRESSURE IMMEDIATELY AFTER TAKEOFF. THEY DECLARED AN EMERGENCY AND RETURNED TO LAND AT THE DEPARTURE AIRPORT.

Narrative: WITHIN MOMENTS AFTER RETRACTING THE LNDG GEAR DURING A NORMAL TKOF ON RWY 1L IN ZZZ; WE RECEIVED A MASTER CAUTION FOR LOW PRESSURE LIGHTS IN BOTH SYS A HYD PUMPS AND ASSOCIATED SYS A FLT CTL LOW PRESSURE LIGHT AND FEEL 'DIFF' LOW PRESSURE LIGHT. WE NOTED THAT THE SYS A HYD QUANTITY HAD DROPPED TO 3%. AFTER ASSESSING THE SIT AND AGREEING WE HAD A TOTAL SYS A HYD FAILURE; WE COMMENCED THE QRH; DECLARED AN EMER WITH DEP AND ARRANGED WITH DISPATCH A RETURN TO ZZZ. FLT ATTENDANTS AND PAX WERE BRIEFED TO EXPECT A NORMAL LNDG. MANUAL GEAR EXTENSION WORKED AS ADVERTISED AND THE LNDG WAS UNEVENTFUL. AFTER LNDG; FIRE RESCUE CREWS NOTICED SOME STEAM VAPOR FROM THE R MAIN GEAR. INFRARED TEMP SENSOR REVEALED NORMAL LNDG BRAKE TEMP AND THE STEAM WAS DUE TO HYD FLUID THAT HAD SPILLED ONTO BRAKE ASSEMBLY. FIRE RESCUE SAID IT WOULD BE SAFE TO TAXI TO THE GATE. TURNING INTO THE GATE OUR ALTERNATE NOSEWHEEL STEERING FAILED (SYS B QUANTITY NOW AT 61%). WE WERE THEN TOWED INTO THE GATE.

Data retrieved from NASA's ASRS site as of January 2009 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.

A B737 flight crew experienced loss of 'a' system hydraulic quantity and pressure immediately after takeoff. They declared an emergency and returned to land at the departure airport.