B757 flight crew reported a loss of pressurization during climb resulting in a return to departure a...

Attributes
ACN	1706548
Time
Date	201911
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	Pressurization System
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 96 Flight Crew Total 6800 Flight Crew Type 5500
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 170 Flight Crew Total 4500 Flight Crew Type 195
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy Flight Deck / Cabin / Aircraft Event Illness

Narrative:

We were climbing out to the north and the first officer was the pilot flying. Passing through about FL280 we received the master warning horn and light and the cabin press EICAS warning. I reached over and returned the left pack to auto (it had been turned off due to dual pack noise); we donned oxygen and established communications and we ran the qrc procedure. I got a clearance to stop the climb at FL290. I saw that the pressure gage read somewhere between 10;000 feet and 15;000 feet cabin pressure. I requested a descent; initially to FL250 and then to 10;000 feet. I did not feel that a max rate decent was warranted due to traffic and weather; so we descended safely but expeditiously. The first officer advised me that he felt some symptoms of hypoxia. During the descent the cabin altitude got below 10;000 feet and the warning horn stopped. I did not know what the problem was since there were no other EICAS or system failure lights. It could have been descending that fixed the problem; or it could have been returning to dual pack operations; or it could have been both. Since I didn't know what problem I had; and since my first officer had indicated that he had been hypoxic; I elected to advise ATC and return to ZZZ. Since I was asymptomatic I flew the approach and landing and there were no further abnormalities. We returned the plane to maintenance.

Original NASA ASRS Text

Title: B757 flight crew reported a loss of pressurization during climb resulting in a return to departure airport.

Narrative: We were climbing out to the north and the First Officer was the pilot flying. Passing through about FL280 we received the master warning horn and light and the CABIN PRESS EICAS warning. I reached over and returned the left pack to auto (it had been turned off due to dual pack noise); we donned oxygen and established communications and we ran the QRC procedure. I got a clearance to stop the climb at FL290. I saw that the pressure gage read somewhere between 10;000 feet and 15;000 feet cabin pressure. I requested a descent; initially to FL250 and then to 10;000 feet. I did not feel that a max rate decent was warranted due to traffic and weather; so we descended safely but expeditiously. The First Officer advised me that he felt some symptoms of hypoxia. During the descent the cabin altitude got below 10;000 feet and the warning horn stopped. I did not know what the problem was since there were no other EICAS or system failure lights. It could have been descending that fixed the problem; or it could have been returning to dual pack operations; or it could have been both. Since I didn't know what problem I had; and since my First Officer had indicated that he had been hypoxic; I elected to advise ATC and return to ZZZ. Since I was asymptomatic I flew the approach and landing and there were no further abnormalities. We returned the plane to Maintenance.

Data retrieved from NASA's ASRS site 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.