British Airways hopes to figure out how its passengers are feeling based on the colour of their blankets.
The airline announced Wednesday it has begun testing a hi-tech blanket that "changes colour using brainwaves."
The "happiness blanket" will change from red to blue when a passenger is relaxed.
The airline said it hopes to monitor relaxation patterns during a flight to help improve in-flight service, such as when food is served, what food is offered and what types of movies to show.
"This is the first time this technology has been used by any airline to help shape how service is delivered on board an aircraft," Frank van der Post, managing director of customer service, said in a press release.
Last week, the airline introduced "slow TV" to long-haul flights. The "wallpaper-style" footage features a seven-hour train ride through Norway, offering a "hypnotic quality" for passengers.