How to write tension scenes - Narrative

Before

He stood at the flying fox and he was really scared. Jacob was sneering at him again.

'You can do it,' said the instructor. 'Trust in yourself.'

Kon took a deep breath. Then he grabbed hold of the bar really tightly and jumped.

After

Heights... heights... he had always hated heights. He fought the thudding of his heart.

His hands gripped the bar of the flying fox. His knuckles were tight and rigid. Below him the valley stretched out, green and deep and far, far below.

'Go on. I dare ya.' It was the voice of Jacob, that faint sneering in his voice as always.

'He's chicken.'

'He won't jump... '

'He'll never do it.' The sounds of Jacob's buddy bullies, seemed to surround him. Sometimes they were worse than Jacob.

Kon fought for breath. Hot prickles of fear and loathing washed over him. He looked down at the valley below. The trees were so tall. The ground was so deep and dark.

'See, I told ya!' Jacob again.

The handle of the flying fox seemed so slippery. Could he hold on?

'Yeah, no hope.'

'Chicken. Cluck, cluck...'

Thick tears of sweat roll down his face. Quickly he lifted a hand and wiped them away. Would they think they were tears?
There was movement beside him, the instructor was saying something. Kon fought to see his face.
'You can do it,' said the instructor. 'You have the courage.' Kon shook his head. His fingers were frighteningly white on the bar.

'Trust me,' said the instructor, 'And trust in you.' The words echoed in his brain. Kon couldn't make sense of them. Yet strangely there was a calmness there, a confidence flowing out to him. The instructor smiled at him.

Kon looked out over the valley and saw the rich green of the tree tops and the glittering strength of the bar he was holding. Somehow he was taking a breath, long and deep. Then another. Then one more.

Then his body tightened and his knees bent and pushed forward. His hands gripped the bar like steel.

Then he jumped off – and flew.