During climbout a B757 lost bleed air from the left engine. Shortly thereafter; the right bleed was ...

Attributes
ACN	789283
Time
Date	200805
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 28000
Environment
Flight Conditions	IMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zzz.artcc
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 173 flight time total : 9522 flight time type : 4630
ASRS Report	789283
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 flight crew : diverted to another airport
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

While climbing thru FL240 with wing & engine anti-ice on; we lost our left bleed. (Left bleed off message). We followed QRH procedure. We continued a step climb to FL280; but aircraft would only climb at 500 FPM. As we leveled at FL280; we lost our right bleed also. With no bleed air; we also lost our cabin pressurization. We put on our oxygen masks; declared an emergency; and began an emergency descent to 10000 ft. I flew the aircraft and coordinated a divert into ZZZ; while the captain ran the checklists and communicated with our flight attendants and passengers. He also manually activated the passenger oxygen system. We diverted and landed at ZZZ.callback conversation with reporter revealed the following information: the reporter stated that maintenance discovered a faulty pneumatic temperature sensor which eventually resulted in the failure and subsequent rupture of the pneumatic ducting from the left engine. When bleed air from this engine was lost; procedures were followed and the bleed isolation valve was opened to allow bleed air from the right engine to provide wing anti-ice to both wings. One pack was also turned off as required by procedure. Bleed air from the right engine was then lost through the failed pneumatic ducting on the left side; and insufficient air was available to pressurize the aircraft through the remaining pack.

Original NASA ASRS Text

Title: DURING CLIMBOUT A B757 LOST BLEED AIR FROM THE LEFT ENG. SHORTLY THEREAFTER; THE RIGHT BLEED WAS LOST; RESULTING IN LOSS OF CABIN PRESSURIZATION AND AN EMER DESCENT.

Narrative: WHILE CLIMBING THRU FL240 WITH WING & ENGINE ANTI-ICE ON; WE LOST OUR LEFT BLEED. (LEFT BLEED OFF MESSAGE). WE FOLLOWED QRH PROCEDURE. WE CONTINUED A STEP CLIMB TO FL280; BUT ACFT WOULD ONLY CLIMB AT 500 FPM. AS WE LEVELED AT FL280; WE LOST OUR RIGHT BLEED ALSO. WITH NO BLEED AIR; WE ALSO LOST OUR CABIN PRESSURIZATION. WE PUT ON OUR OXYGEN MASKS; DECLARED AN EMERGENCY; AND BEGAN AN EMERGENCY DESCENT TO 10000 FT. I FLEW THE AIRCRAFT AND COORDINATED A DIVERT INTO ZZZ; WHILE THE CAPTAIN RAN THE CHECKLISTS AND COMMUNICATED WITH OUR FLIGHT ATTENDANTS AND PASSENGERS. HE ALSO MANUALLY ACTIVATED THE PASSENGER OXYGEN SYSTEM. WE DIVERTED AND LANDED AT ZZZ.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE REPORTER STATED THAT MAINT DISCOVERED A FAULTY PNEUMATIC TEMP SENSOR WHICH EVENTUALLY RESULTED IN THE FAILURE AND SUBSEQUENT RUPTURE OF THE PNEUMATIC DUCTING FROM THE LEFT ENG. WHEN BLEED AIR FROM THIS ENG WAS LOST; PROCEDURES WERE FOLLOWED AND THE BLEED ISOLATION VALVE WAS OPENED TO ALLOW BLEED AIR FROM THE RIGHT ENG TO PROVIDE WING ANTI-ICE TO BOTH WINGS. ONE PACK WAS ALSO TURNED OFF AS REQUIRED BY PROCEDURE. BLEED AIR FROM THE RIGHT ENG WAS THEN LOST THROUGH THE FAILED PNEUMATIC DUCTING ON THE LEFT SIDE; AND INSUFFICIENT AIR WAS AVAILABLE TO PRESSURIZE THE ACFT THROUGH THE REMAINING PACK.

Data retrieved from NASA's ASRS site as of May 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.

During climbout a B757 lost bleed air from the left engine. Shortly thereafter; the right bleed was lost; resulting in loss of cabin pressurization and an emergency descent.