767 seat belt sign

[Flying Torquewrench]

Hi all,

With a decompression does the seatbelt sign come on automaticly? Is there a pressure switch in it which switches it on when the cabin pressure exceeds a certain value. According to a F/A i was speaking to it does but i am not sure.

Thank you.

[None]

This is a cut and paste from the Boeing Manual. You can see that even if the seat belt selector is off, the signs will illuminate if the cabin is above 10,000:

"Passenger Cabin Signs
The passenger cabin signs are controlled by overhead panel selectors. The
passenger signs illuminate when the following conditions are satisfied:
FASTEN SEAT BELTS signs (AUTO selected):
• cabin altitude above 10,000 feet
• landing gear not up and locked
• flap lever not up
• passenger oxygen on

NO SMOKING signs (AUTO selected):
• cabin altitude above 10,000 feet
• landing gear not up and locked
• flap lever not up
• passenger oxygen on

All passenger signs can be controlled manually by positioning the respective
selector to ON or OFF. When the FASTEN SEAT BELTS and NO SMOKING
selectors are in the OFF position, and oxygen is ON or the cabin altitude exceeds
10,000 feet, the FASTEN SEAT BELTS and NO SMOKING signs illuminate."

[Flying Torquewrench]

Thank you None,

That was exactly what i was looking for.

Cheers, FT

[Easy226]

In turbulent conditions, do the seat belt signs automatically illuminate or are they manually controlled by the pilot. I was under the impression that the signs would illuminate automatically if a turbulent condition was present?

Many Thanks

Dan