What is the Time Up Cabin (TUC) for 35,000 feet?

• A. 30 Seconds to 1 Minute
• B. 15-20 Seconds
• C. 3-5 Minutes
• D. 1-2 Minutes

Answer: (A)

Time Up Cabin is the short window you have to become oxygenated and start actions after a loss of cabin pressure at altitude. At 35,000 feet, the brain can’t tolerate hypoxia for long, so the usable time is very limited—roughly 30 seconds to 1 minute. This brief window is why flight crew are trained to immediately don oxygen and initiate descent to restore cabin pressure. The other durations are either too short or too long given the rapid onset of hypoxia at that altitude, so they don’t align with standard procedures.