Two 84-year-old twins are to jump from an aircraft along with four grandchildren for a charity skydive to raise money for the British churches' international development group Christian Aid and a cancer fund.

Pensioners Frank and Ralph Land will be jumping out of a plane at 8000 feet (2,440 meters) on April 1 - April Fool's Day - to raise money to support some of the world's poorest people.

"On this occasion I will be skydiving with my 84 year old twin brother Frank and four of his grandchildren, in part to celebrate his 60th wedding anniversary to Ailsa and in memory of my wife Jacqueline who died of Pancreatic Cancer three years ago," wrote Ralf Land on a website set up for the stunt.

"Half the proceeds of the skydive will go to Christian Aid to support a number of very necessary international projects to aid, at least, some of the millions of vulnerable children caught up in war zones, natural disasters and poverty.

He said the other half will go to Cancer Research UK, to seek treatment for a devastating cancer with, currently, very low survival rates.

"So please dig deep and donate now," said Land.

Ralph, from London, is doing the dive in memory of his wife Jacqueline, who he lost to pancreatic cancer three years ago, and to help Frank celebrate his 60th wedding anniversary.

Frank Land, who lives in Totnes in southwest England, said of his marriage to his wife Ailsa: "In our 60 years together we have brought up a family and have completed fulfilling careers in industry and academia.

"But in that time we have seen much misery worldwide, particularly in the less developed world," he said.

"Our diamond jubilee brings our family and some good friends together, and provides an opportunity for all of us to make some contribution to the lives of others less fortunate then ourselves.

"Christian Aid's initiative in organizing the sky dive in the middle of our celebrations was too good an opportunity to miss.

"I tried to convince my children to take part, but they refused. However, my grandchildren agreed to do it instead, so it will be the oldies and the young 'uns."

Accompanying the pair on their charity plummet are Frank's grandchildren Izzy Burr, aged 28, from Totnes, Emma Place, aged 22, a student at Nottingham University, Adam Place, aged 26, and Chloe Place, aged 24, both from Bristol.

The jump will take place at 10 a.m. on April 1, 2013 at Dunkeswell Airfield, in Devon, southwest England.

Christian Aid is a member of the Geneva-based ACT Alliance one of the world's biggest emergency aid and development agencies that is backed by global churches.