B727 flight crew has loss of 'a' hydraulic system on departure from mmun.

Attributes
ACN	595027
Time
Date	200309
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : mmun.airport
State Reference	FO
Altitude	msl single value : 29000
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : mmex.artcc tower : eddf.tower
Operator	common carrier : air carrier
Make Model Name	B727-200
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : instrument pilot : flight engineer pilot : commercial pilot : cfi pilot : atp
Experience	flight time last 90 days : 120 flight time total : 6000 flight time type : 3500
ASRS Report	595027
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : hyd quantity indication other flight crewa
Resolutory Action	flight crew : landed as precaution flight crew : diverted to another airport flight crew : declared emergency
Consequence	other
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Aircraft

Narrative:

On climb out, 'a' system hydraulics showed a slow leak. 'A' system pwrs items such as flaps, landing gear and nosewheel steering, only 25 mins after takeoff over the gulf of mexico at night in thunderstorm conditions, I elected to return to point of departure in cancun, mexico. Another failure ('B' system) would render the aircraft unsafe because controls would operate manually and would be hard to control at high speed. At the commencement of the 'a' hydraulic system checklist and declaration of an emergency, I elected to return to cancun. Our weight was 164000 pounds. When the checklist advised to dump fuel to ge to 161000 pounds (maximum landing weight), I elected to move along assuming we would burn the 34000 pounds of descent and approach. The flight engineer was busy enough running checklists to worry about dumping 1000 pounds of fuel. Provisions are made per the airline manual for an overweight landing, in case of emergency. Crew and passenger were briefed and landing occurred at 300 FPM. 360 FPM or greater requires a hard landing check per the manual. Once stopped, ground crew attempted to tow airplane but #1 and #2 brakes did not release and passenger had to be bussed to terminal.

Original NASA ASRS Text

Title: B727 FLT CREW HAS LOSS OF 'A' HYD SYS ON DEP FROM MMUN.

Narrative: ON CLBOUT, 'A' SYS HYDS SHOWED A SLOW LEAK. 'A' SYS PWRS ITEMS SUCH AS FLAPS, LNDG GEAR AND NOSEWHEEL STEERING, ONLY 25 MINS AFTER TKOF OVER THE GULF OF MEXICO AT NIGHT IN TSTM CONDITIONS, I ELECTED TO RETURN TO POINT OF DEP IN CANCUN, MEXICO. ANOTHER FAILURE ('B' SYS) WOULD RENDER THE ACFT UNSAFE BECAUSE CTLS WOULD OPERATE MANUALLY AND WOULD BE HARD TO CTL AT HIGH SPD. AT THE COMMENCEMENT OF THE 'A' HYD SYS CHKLIST AND DECLARATION OF AN EMER, I ELECTED TO RETURN TO CANCUN. OUR WT WAS 164000 LBS. WHEN THE CHKLIST ADVISED TO DUMP FUEL TO GE TO 161000 LBS (MAX LNDG WT), I ELECTED TO MOVE ALONG ASSUMING WE WOULD BURN THE 34000 LBS OF DSCNT AND APCH. THE FE WAS BUSY ENOUGH RUNNING CHKLISTS TO WORRY ABOUT DUMPING 1000 LBS OF FUEL. PROVISIONS ARE MADE PER THE AIRLINE MANUAL FOR AN OVERWT LNDG, IN CASE OF EMER. CREW AND PAX WERE BRIEFED AND LNDG OCCURRED AT 300 FPM. 360 FPM OR GREATER REQUIRES A HARD LNDG CHK PER THE MANUAL. ONCE STOPPED, GND CREW ATTEMPTED TO TOW AIRPLANE BUT #1 AND #2 BRAKES DID NOT RELEASE AND PAX HAD TO BE BUSSED TO TERMINAL.

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.