JOHANNESBURG (AP) -- The power of ideas nourished Nelson Mandela during his confinement on Robben Island, but even this visionary might not have imagined the surreal scene planned for this month at the outpost where he spent 18 of 27 years as a prisoner of apartheid.
Wind speed and direction permitting, a man in a harness will strap himself to 200 big balloons filled with helium, float off the island beneath a bulging latex column of color, and drift to the shores of Cape Town for a charitable cause.
There are a few things he wants to avoid: an international airport, a major harbor, a nuclear power station, and the odd shark in the waters below.
"Apart from all those hazards, there's nothing to worry about," said Matt Silver-Vallance, a South African-born manager at a medical device company who will pilot the whimsical craft.
Civil aviation authorities say they are satisfied with safeguards for what should be a lazy meander in the breeze rather than an edge-of-your-seat stunt.
The goal of the trip is to raise $1 million to help build a children's hospital named after 94-year-old Mandela, who became South Africa's first black president in democratic elections in 1994 after negotiating an end to white racist rule.
Mandela was admitted last week to a Pretoria hospital because of a recurrence of pneumonia, prompting expressions of concern from South Africans and people around the world. On Monday, the office of President Jacob Zuma said family members visited Mandela at the hospital.
"It refocuses everybody on his legacy," Silver-Vallance, who lives in Britain, said Tuesday of Mandela's illness. Referring to the former leader, he said: "You think about all the contributions that a person makes in their life, but also beyond their life as an example to others."
The guardians of Robben Island, a somber site, concluded that the cluster balloon flight, while quirky, was consistent with the spirit of daring and altruism that Mandela personified in the struggle against apartheid.
"This is something that we can identify with," said Shoni Khangala, director of communications and marketing for the Robben Island Museum. He said it was important to celebrate that spirit "without necessarily shedding tears all the time."
The planned voyage, estimated to take about an hour, is a form of flight known as cluster-ballooning. The hobby is expensive and eccentric. As a spectacle, a spur to the imagination, it's up there in the clouds.
"There isn't a kid that hasn't wondered: 'How many of these do I need to make me fly?'" said Mike Howard, an airline pilot in Dubai and cluster-balloonist who is advising Silver-Vallance. "When you see someone doing it, it's one of those dreams you had as a child, and now you see it in reality."
Cluster-ballooning got a boost in in popular culture with the 2009 computer-animated movie "Up," featuring an elderly man who ties lots of balloons to his house and flies off with a young stowaway on board.
Pilots in two motorized paragliders will accompany Silver-Vallance, as will four boats, including one from the South African navy that will transport media and other guests.
He will only fly in gentle winds and stay low at 180 meters (600 feet), below the height of more conventional aircraft. He will carry radio equipment and a long rope that he can toss to his beach crew if he loses control while landing.
Silver-Vallance, 36, can climb in altitude by ejecting waterbags that serve as ballast, and reduce elevation by shooting out balloons with an air pistol, or stabbing them with scissors or a blade fixed to a bamboo stick.
He'll aim to fly sometime between this weekend and April 27, deemed the most cooperative time of the year for wind currents, and travel at least 9 kilometers (5.6 miles), which is the shortest distance between the island and the mainland.
Mandela described in a memoir how he and other comrades were transferred to Robben Island in the 1960s and subjected to hard labor and other tough conditions. Today, visitors tour the cramped cells, the exercise yard and the quarry where inmates toiled.
"Moving from one prison to another always requires a period of adjustment," Mandela wrote. "But journeying to Robben Island was like going to another country. Its isolation made it not simply another prison, but a world of its own, far removed from the one we had come from."
Silver-Vallance's escapade adds to the lore of an island that served as a prison under Dutch settlers in the 17th century. At that time, a jailed local leader escaped to the mainland. In 1819, a Xhosa chief who opposed colonial rule drowned after trying to escape.