Get set for a fantastic two days' entertainment.

That is the upbeat message today from the organisers of the Lowestoft Seafront Air Festival as tens of thousands of people converge on the town for the annual spectacular.

The event has become vital to Waveney's tourism industry, bringing in an estimated �11.9m to the local economy. But with the costs of staging the airshow continuing to rise, visitors are being urged to make a minimum donation of �3 this year to ensure it continues.

Paul Bayfield, the airshow's managing director, said: 'We've assembled a small army of 300 volunteers from local community groups who will be on duty to collect entrance donations. What they're hoping for is a �3 per person donation in return for a fantastic family day out, with wonderful attractions and a feast of fantastic flying.'

The Red Arrows will once again headline the show, as they have done for all but one of the event's 15 years. They will close this afternoon's programme and get Friday's displays off to a spectacular start at 12.30pm.

Organisers have lined up four and a half hours of flying on both days and among the other highlights – announced only this week – are a pair of United States Air Force F-15E Strike Eagle fighter jets.

As a bonus, there will be a special sail-past by classic racing bots, motor cruisers and rigid inflatables. The small fleet will set sail from the Royal Norfolk and Suffolk Yacht Club at 10.30am on both days for an hour-long parade along the coast, providing a prelude to the aerial displays.

The show's flying display director Brian Lewis, who has been involved in planning 12 of the 14 previous air festivals, said he was excited by the line-up.

He said: 'The Royal Air Force has been exceptional in providing so many display aircraft for us in the face of quite savage financial restrictions. They, together with the many civilian aircraft taking part, are the result of careful negotiations.'

All those who put �3 in bucket collections will receive a two-for-one voucher from Pleasurewood Hills and a discount on tickets at this year's Marina Theatre pantomime.