17-year-old Samuel was trapped in a car. His Australian dad's gut instinct saved his life.

When 17-year-old Samuel Lethbridge didn’t make it to a friend’s house on Sunday, police feared he’d run away. But his dad Tony knew his son wouldn’t do that.

“Everybody was saying he’s probably run away … [but] that’s just not Samuel,” the father NSW from told Sunrise.

That gut instinct is what ultimately saved his son’s life. After an extensive search along NSW’s Central Coast failed to find any sign of Samuel or his car, Tony remembered a fatal car accident that happened five years ago on the Pacific Highway at Crangan Bay, south of Newcastle.

He then knew what to do.

Tony made the drastic decision to hire a helicopter to widen the search and on Monday morning, after 10 minutes in the air with Samuel’s uncle, Michael, they spotted the white car crashed 20 metres down a bank off the Pacific Highway in bush land not visible from the road where they’d been searching.

Samuel had been trapped there for 30 hours.

“I thought… I can’t leave him out there without looking so yeah we went and hired the helicopter straight away and found him within ten minutes,” Tony said.

Michael added, “It was an absolute wreck, and I was a little bit afraid of what I might find”.

It took rescue crews almost an hour to cut the teenager free from the wreckage, after which he was flown to John Hunter Hospital with injuries to his ankle, forearm, spine and femur, News.com.au reports.

NSW Ambulance superintendent, Jeff Atkins described the rescue operations as "difficult".

"It was a very extensive rescue, very difficult access, difficult extrication of the patient, [we’re] very lucky the young patient is still alive," her said.

“He’d been there all night. No one could see him from the road, no one at all. He was trapped extensively in the car from the waist down and was fully conscious through the whole ordeal."

Samuel remains in intensive care in a critical condition, but is "on the mend".

"They said he wouldn't have lasted a great deal longer," Tony said.

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