Apple users have started accidentally triggering the iPhone 14’s crash detection system while riding rollercoasters leading to questions about the feature’s accuracy.

Crash detection is an Apple feature announced during the company’s iPhone event last month.

It uses a suite of sensors, like gyroscopes and accelerometers, to tell when a customer has been in a car accident.

When they detect a crash, the device starts a 20-second countdown. If the user doesn’t respond in time, it will automatically call emergency services.

Unfortunately, this isn’t a perfect system.

As the Wall Street Journal’s Joanna Stern wrote in a much-shared article this week, Apple’s crash detection has been making false alarms near amusement parks in the US.

In the month since the new iPhone was released, one emergency call centre said it had received half a dozen calls originating from just one theme park and on at least one occasion dispatched a team of emergency responders who discovered nothing but carnival-goers having a fun time.

Stern shared audio recordings of the automated phone calls in which you can hear the distant screams of rollercoaster riders.

“The owner of this iPhone was in a severe car crash and is not responding to their phone,” a robotic voice says before giving precise latitude and longitude of the phone and repeating the message in full.

Not only does crash detection call emergency services, it also sends messages to the user’s emergency contacts notifying them of the car crash if they don’t respond.

For one man who was riding his motorcycle shortly after buying an iPhone 14, that feature caused anguish for his loved ones when his new phone accidentally flew off the bike and triggered an alert.

Along with calling emergency services, the phone also texted his mum and girlfriend. They were understandably upset.

“I was freaking out. I was thinking the worst,” the girlfriend told the Wall Street Journal. “My best friend passed away in a car accident. It brought me right back there.”

It’s clear how crash detection could save lives, especially for accidents in isolated rural areas that may otherwise go unnoticed by passersby for hours.

Already the system, which is switched on by default in new model iPhones and Apple Watches, has alerted emergency services to fatal crashes and could one day save lives by calling first responders to the scene immediately.

For the time being, Apple said it will continue iterating on the feature and improving its accuracy.

The company said it uses a range of metrics to determine whether what its devices are experiencing is a car crash or just a rollercoaster.

Along with gyroscopes, accelerometer, and GPS to determine movement, devices also pick up crash sounds from the microphone, and even take indications from a barometer to measure changes in air pressure from when airbags go off.

In a recent interview with TechCrunch, Apple’s Vice President of Sensing and Connectivity Ron Huang said there was a variety of data that could be fine-tuned as the feature is developed.

“It’s hard to say how many of these things have to trigger, because it’s not a straight equation,” he said.

“Your speed change, combined with the impact force, combined with the pressure change, combined with the sound level – it’s all a pretty dynamic algorithm.”