B757 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 120; Flight Crew Total 12000; Flight Crew Type 4000
Troubleshooting; Communication Breakdown; Confusion; Distraction; Physiological - Other
ATC Issue All Types; Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Other / Unknown
Flight Crew Overcame Equipment Problem; General Declared Emergency
Human Factors; Aircraft
Level at FL380 approaching top of descent; we received a Right Pack Off and Right Pack Temp message. As we started the checklist for Right Pack Off; we received a Left Pack Off and Left Pack Temp message. All three of us including a company jumpseater donned oxygen masks and I asked for lower altitude. ATC kept giving us lower altitudes but not 10;000. I declared emergency with ATC. Jumpseater was working through checklist while I talked to ATC; captain kept flying airplane. Captain never switched to oxygen for his mic so I couldn't understand what he was asking me to do; jumpseater in the normal observer seat (behind FO) doesn't have a radio control panel so it was hard to understand what he was saying too. We eventually reset both packs and regained control of cabin altitude as it was reaching 10;000. Leveled off at FL240 and remained there until we started normal descent into our destination.
When both left and right packs over temped and shut down; the flight crew of a B757 began an emergency descent and declared an emergency. Communication on the flight deck was compromised by improper use of the oxygen mask microphones. The packs were reset during the descent; the cabin stabilized at 10;000 feet; and the descent stopped at FL240. A normal descent for landing was made as they approached their destination.