How many times does the decompression PRAM automatically play on the 787?

How many times does the decompression PRAM automatically play on the 787?

• A. One
• B. Two
• C. Three
• D. Four

Answer: (C)

During a decompression, the 787’s automated alert system uses a pre-recorded message (PRAM) to quickly inform everyone and guide them to safety actions. That message is set to play automatically multiple times to cut through cabin noise and catch the attention of as many passengers as possible. The three-repeat plan provides a reliable level of repetition: it reinforces the instruction to don oxygen masks and follow crew directions without overdoing the disruption in the cabin. If it played only once, some passengers might miss it; with two plays it could still be missed by some; four plays would be more than necessary and could become overly intrusive. So three automatic plays is the balance designed into the system.

During a decompression, the 787’s automated alert system uses a pre-recorded message (PRAM) to quickly inform everyone and guide them to safety actions. That message is set to play automatically multiple times to cut through cabin noise and catch the attention of as many passengers as possible. The three-repeat plan provides a reliable level of repetition: it reinforces the instruction to don oxygen masks and follow crew directions without overdoing the disruption in the cabin. If it played only once, some passengers might miss it; with two plays it could still be missed by some; four plays would be more than necessary and could become overly intrusive. So three automatic plays is the balance designed into the system.