STORY: Singapore Airlines is to compensate passengers who were on the flight hit by violent turbulence in May.

A 73-year old man died of a suspected heart attack during the incident.

Dozens more required hospital treatment, with brain, spinal and skull injuries reported.

The flight was en route from London to Singapore when it encountered what the airline called sudden, extreme turbulence.

Passengers not strapped in were slammed into the cabin ceiling, smashing holes in it in places.

By early June, 20 travelers were still receiving treatment in Bangkok, where the plane made an emergency landing.

Now the airline says passengers with minor injuries have been offered a $10,000 payment.

Those with more serious injuries have been offered $25,000 up front, and can discuss further support to meet their future needs.

Everyone on the flight will get a refund and delay compensation.

A preliminary report by Singapore's Transport Ministry says the jet experienced a sudden drop as it was flying through bad weather.

The incident has put seatbelt practices in the spotlight, with airlines generally allowing travelers to undo their belts during the cruise phase of a flight.