All Nippon Airways (ANA) is trying to find out how to stop babies from crying during take-off and landing on planes.

On a charter domestic flight on Sunday (Oct. 1) carrying 34 families including 36 babies, the Japanese carrier took vitals from the children, such as their pulse, using a device developed by Japanese communications company NTT and industrial-products maker Toray, which also participated in the study, according to Japanese media reports. The families were employees of the companies taking part in the study.

ANA estimates that children below the age of three make up about 1.6% of its passengers on domestic flights, and 0.8% on international flights. The airline said that some parents avoid flying (link in Japanese) because they worry their babies will disturb other passengers.

The charter flight was launched as part of an ANA project whose title translates roughly as “An airplane without crying babies!?” The device sent heart rate and other information to smartphones to prompt parents to help their babies sip from a cup made by another participating company, or else suck on tablet-like sweets.

Recommendations to have babies nurse or suck on a pacifier during take-off and landing, when cabin pressure changes can cause ear pain, are already routine suggestions to parents. It’s not clear how ANA plans to develop this project—the airline didn’t respond to queries from Quartz. More importantly, the effort may not be getting to the real heart of the problem: excessive adult distress over crying babies.

Some believe that Japanese society is more intolerant of crying children—and noise made by children more generally—than others. One mother of two this year launched a campaign (paywall) with the slogan “it’s fine to cry!” printed on stickers, with supporting companies and stores distributing those stickers for free.

“It’s fine to cry!”

A recent column (paywall) in the Financial Times argues that the large number of women in Japan who say that they’ve experienced reactions in public to their baby crying stems in part from Japan’s ultra-low birthrate. Last year the number of births in Japan, a country of 127 million, slipped under one million for the first time. Many have grown unaccustomed to the noise of children around them, or to caring for a child. Being cooped up on a plane with a baby may be the first time that some Japanese adults spend any length of time with one.

Still, being irritated by crying babies is by no means solely a Japanese trait. Some airlines, like Malaysian Airlines, have moved to ban children from particular areas of the plane, a step that others believe merely shames parents. US airline JetBlue on one occasion bribed passengers to be more tolerant of babies crying. And some advise parents to distribute drink coupons and other goodies to those seated nearby—a tall order in terms of organization for a harried parent—to gain forbearance from nearby childless passengers. Any research findings that can help bridge the gap will be welcome.

