Ian ClarkeHe's been hired - and will be fired!But human cannonball David Smith Jr is certainly no apprentice having been shot in to the air no fewer than 5000 times.Ian Clarke

He's been hired - and will be fired!

But human cannonball David Smith Jr is certainly no apprentice having been shot in to the air no fewer than 5000 times.

And the daredevil thrill-seeker - who reaches a speed of 0-50mph in one fifth of a second - was yesterday in Norfolk to promote his performances at this year's Royal Norfolk Show, which is being staged on Wednesday July 1 and Thursday July 2.

'Come along and cover your ears and don't blink!' was David's message to showgoers ahead of his four shots over the two days, which will last about four seconds each.

He expects to be fired up to 160ft across the grand ring at the Costessey showground and 70ft in the air and will experience G force acceleration of about 9g on take off - that compares to an estimated 5.3g for a top-fuel dragster.

The way he is fired from the cannon is a 'family secret' but David still admits to experiencing some fear.

'It is not out of control terror like it was and has been at times. I am a seasoned veteran but there is something about being in a 33ft cannon which is very nerve racking! There is a massive amount of adrenalin. But I am aware of the seriousness of what I do.'

David thrilled Norfolk Show crowds two years ago and yesterday revealed he had been recovering from a compressed vertebrae at the time, which had been a potentially life threatening injury.

'It is good to be back in Norfolk. I remember that I brought my wife and family over and we had a great experience here and really enjoyed ourselves. We were treated so well and had a tremendous response. We had good crowds even when it was raining.

David - a 32-year-old father-of-four added: 'It is a great show site and you are up close to the audience and we can shoot right across the ring.'

His longest distance he has been shot is 181ft - which was a world record at the time - but the record of 201ft is now held by his father David Snr, who remarkably still gets shot across all manner of venues despite being 67.

'He is still on the rampage and is incredibly physically fit and has retired five times!' said David about his father.

There are only about 10 human cannonballs in the world - and five of them are in David's family

David was first shot out of a cannon when he was 17 and performed about a year later in a show to replace his father, who had hurt his back.

'I was painting beach houses in North Carolina and checked my answering machine and was told I was needed the day after tomorrow to do my first proper shot.'

David was relaxed as ever yesterday he had his picture taken on the top of the cannon with a Superman-style pose, his thumbs up and even pulling a face.

He will be fired from the cannon in the main ring at the showground on both days - on the Wednesday his shows are at 1.20 and 5.10pm and on the Thursday they are at 11.15am and 5.30pm.