HARDCORE: Cameron Macrae, TJ Campbell and Kenneth Macrae liven up Ada St with an experiment into trolley racing.

Three Palmerston North flatmates who believe they have invented the sport of trolley parachuting say there are more antics to come.

But police say their activity is stupid and dangerous.

Third year Massey University students TJ Campbell, Kenneth Macrae and brother Cameron Macrae, videoed themselves towing the parachute-stabilised trolley behind a Nissan Pulsar six times on Ada St on Tuesday.

One of them drove, one of them sat in the boot holding the trolley and one of them sat in the trolley as they reached speeds high enough to inflate the custom-designed sheet-chute.

The video of the stunt, along with others shot by passers-by, are now circulating on social media.

Palmerston North police have described the "creation" as dangerous and stupid and believe it could constitute an arrestable offence if they catch them doing it on the road.

But the three "Ada Hardcore" residents said they felt the risk was not too high because the parachute stopped the trolley from fishtailing.

"It's freaky, it's like going on a rollercoaster," Campbell said.

"When we did it we were just screaming, we were so stoked and really excited that we'd come up with a creation of our own and pulled it off."

The idea to create the parachute was Cameron Macrae's, and he told the Manawatu Standard there were more ideas around the corner.

"We're just making history really. I don't think people have seen this before. It was worth the four hours of making it.

"There will be loads of people out there that have pushed their mates around but I bet they've never achieved the speeds we did.

"We are going to go on to bigger and better things.

"We're really keen on testing a floating trolley in the next few weeks and turn the sheet into a sail."

Kenneth Macrae said the K-mart trolley had been found on Ada St earlier in the week and had been the catalyst for the "creativity".

Plastic bags did not work, a barbecue cover was too heavy for the chute, but the sheet worked really well, he said.

"We thought it through quite a bit before we did it.

"The first aim we had was to see if the parachute would actually slow us down, so we were going to launch the trolley and see if it stopped before the [Ada and Ferguson St] traffic lights. We realised pretty quickly that was a bit too hardcore."

He said he did not want others attempting to copy the design themselves or for the challenge to spread as a craze like #neknominate videos.

"It gets to the point where it starts getting stupid and everyone tries to one-up each other and we don't want that.

Palmerston North police Senior Sergeant Brett Calkin said he was concerned about the safety of those involved and police were not afraid to prosecute this sort of behaviour.

"If they were caught doing that, then clearly the driver of the vehicle would be charged with dangerous driving.

"It's a pretty silly thing to do."

With students starting to arrive in town for another year Calkin said they needed to act responsibly.

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