Each week, the BBC Autos editors select their favourite transport-related news stories, features and videos from around the web. This week, we noticed a trend toward offering creative solutions to global transportation problems. Some of the suggestions are quirky, innovative and intelligent, but others are likely to make travellers groan — or giggle, at best.

Carry on without your carry-on

In an effort to save money and increase customer spending, United Airlines will restrict some passengers’ access to overhead compartments. The Huffington Post reports that United will be the first US airline to limit “basic economy” flyers to a single free carry-on bag that can fit under a seat. In other words, starting next year, those who purchase the cheapest fares will only be allowed one personal item that fits under the seat in front of them. In addition, customers buying these low-fare tickets will be unable to accrue airline miles and will be randomly assigned seating the day of the flight.

United’s move to limit carry-on bags and charge more for flying perks isn’t a novel concept. As BBC Autos reported back in October, airlines are struggling with reducing cargo weight. Because heavier bags — and heavier passengers — result in significantly higher fuel bills, airlines such as Samoa Air have implemented a “fat tax” that means overweight passengers have to pay more for a ticket.

Paper bike helmet wins big

A paper bike helmet has been awarded this year’s international James Dyson Award, BBC News reports. The foldable, recyclable helmet was invented with bike-share riders in mind and will cost less than $5. Best of all, it’s a tough and effective head protector.

"When I was exploring new cities I had no access to a helmet and I didn't want to spend $30 buying one," EcoHelmet designer Isis Shiffer told the BBC. Shiffer will receive £30,000 to develop the helmet planned for New York City release in 2017.

Japan’s quick sinkhole fix

After a sinkhole consumed a busy portion of a road in Japan, construction workers in the city of Fukuoka jumped into action, mending the sunken road in record time. According to BBC News, the patched-up road was reopened to traffic within a week of having been consumed by the earth below it. The city's Mayor Soichiro Takashima released a statement thanking road workers for quickly and efficiently converting the destroyed road into a fully functional one.

Grandad’s Coke pool rust-removal stunt goes wrong

Not only are fizzy drinks capable of rotting teeth, they can also remove rust. One Latvian grandfather decided to put cola to the ultimate rust-removal test by submerging his car in a pool of Coca-Cola. In a video posted online, the unnamed daredevil grandad fills a lined pit with 6,000 two-litre bottles of Coke. He then settles into the driver’s seat and speeds into the hole, smashing the front of his red Audi. Whether or not the rust was removed is unknown, but the Daily Mail contends that “improvement in the amount of rust on the car was more than outweighed by the damage to the vehicle.”

MTA reconsiders subway safety barriers

More than 40 people have been killed by New York City subway trains so far this year, which has the city’s Metropolitan Transportation Authority board members reconsidering the installation of safety barriers separating the train tracks from platforms. This particular safely precaution is already employed around the globe, including stations in Paris, London and Tokyo.

“It won’t eliminate all that, but clearly, as my daughter rides the train, I think many parents, young people of all ages, would be reassured with some protective devices, particularly at the overcrowded stations,” MTA board member David Jones told the New York Daily News.

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