It's the kind of nightmarish scenario to keep you awake at night.

Half an hour into their journey, passengers on Southwest flight 1380 heard an explosion and suddenly oxygen masks descended from above.

The plane began descending rapidly and messages from the pilot couldn't be heard over the air suddenly whistling around the cabin.

Someone was screaming for help in the 14th row.

Like probably everyone else on board, Matt Tranchin feared he was about to die.

The community organiser was returning to Dallas, Texas, where wife Molly is seven months pregnant with their baby son.

Matt Tranchin sent an emotional text message to his heavily pregnant wife (
Image:
Twitter)
Mum Jennifer Riordan was tragically killed in the incident
Matt was next to passenger Marty Martinez who captured his 'final moments' on FacebookLive (
Image:
Marty Martinez / Facebook)

The father-to-be has shared the heartbreaking message he sent her: "Our baby boy is everything.

"You are my everything.

"Marrying you was the best moment and decision I ever made.

"If I don’t make it, please know I’m truly happy. Because of you. Your love."

It was one of several gut-wrenching texts sent by passengers to loved ones.

Registered nurse Peggy Phillips managed one line to her daughter: "Plane trouble. I love you."

The left engine exploded mid-flight (
Image:
Twitter/Joe Marcus)

She told the Dallas Morning News how she sprung into action after the crew asked for anyone trained in CPR.

Peggy battled for a long period to try and save mum-of-two Jennifer Riordan who was tragically sucked out of the plane window.

It is believed to have shattered after being hit by shrapnel when the left engine blew.

Hollie Mackey, a professor, was in seat 14A and told how she and a little girl say beside Mrs Riordan tried to pull her back in - but they weren't strong enough.

"When I saw Jennifer... I had leaned over and grabbed on to her belt loops and her waist and wrapped my arm around her waist and tried to pull," she told KTVQ news channel.

"And the little girl next to me also tried to pull with me, and we tried to pull her back in, and we couldn't.

"We were not strong enough.

"All we could do was stay calm, because if we didn't then there would be even more panic in the plane."

Mrs Mackey said she could do was "wait" with the little girl in the hope help would arrive.

Mrs Riordan was sucked out of the window (
Image:
Marty Martinez / Facebook)
Investigators examine the damage to the engine (
Image:
REUTERS)

Fortunately it did, in the form of firefighter Andrew Needum and another passenger Tim McGinty who was sat across the aisle.

The two men were able to pull Mrs Riordan back in though sadly her injuries proved fatal.

(
Image:
NBCDFW)

Flight 1380 landed safely at Philadelphia thanks to the nerves of steel displayed by pilot Tammie Jo Shults.

She waited by the door and personally embraced each passenger as they left the plane.

The survivors were taken to a hangar where they all desperately called loved ones to tell them what had happened.

Nurse Peggy added: "I saw passengers patting each other and helping each other get out of seats and giving words of encouragement.

"It's really amazing the bonding with total strangers that happens after something like this."