B757 flight crew reported the flight diverted due to loss of both air conditioning and pressurizatio...

Attributes
ACN	1585137
Time
Date	201810
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	Mixed
Light	Night
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Route In Use	Other Controlled
Flight Plan	IFR
Component
Aircraft Component	Air Conditioning and Pressurization Pack
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Instrument Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 125 Flight Crew Total 10000 Flight Crew Type 749
Person 2
Function	Pilot Not Flying Captain
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 50 Flight Crew Total 4500 Flight Crew Type 8
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

As we were climbing to 34;000 we received the right pack off indication and the associated [alert] messages. We were right in the tops of the clouds and requested a climb to 36;000 to try and get in the clear sky. We had been flying with the left pack in the off position; due to the cockpit noise levels. As soon as the right pack off indications happened we immediately selected the left pack back to auto. Shortly after this; but before reaching 36;000; the left pack off indications posted. Bleed pressure for both systems now read zero. At this time we began an immediate descent to 10;000 feet and continued the pack off checklist. We determined that the nearest suitable airport to us was ZZZ. There were thunderstorms in the area; which required some deviating; but the temperatures were high enough that anti-ice was not required. We set up for and briefed the ILS at ZZZ and landed without incident. We informed center; approach and tower that no further assistance was required.

Original NASA ASRS Text

Title: B757 flight crew reported the flight diverted due to loss of both Air Conditioning and Pressurization Packs and landed without further incident.

Narrative: As we were climbing to 34;000 we received the Right Pack off indication and the associated [alert] messages. We were right in the tops of the clouds and requested a climb to 36;000 to try and get in the clear sky. We had been flying with the Left pack in the off position; due to the cockpit noise levels. As soon as the right pack off indications happened we immediately selected the left pack back to auto. Shortly after this; but before reaching 36;000; the left pack off indications posted. Bleed pressure for both systems now read zero. At this time we began an immediate descent to 10;000 feet and continued the pack off checklist. We determined that the nearest suitable airport to us was ZZZ. There were thunderstorms in the area; which required some deviating; but the temperatures were high enough that anti-ice was not required. We set up for and briefed the ILS at ZZZ and landed without incident. We informed Center; Approach and Tower that no further assistance was required.

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.

B757 flight crew reported the flight diverted due to loss of both air conditioning and pressurization packs and landed without further incident.