Steve Saint, the 61-year-old son of martyred MAF missionary, Nate Saint, has been seriously injured in Gainesville, Florida, while testing new missionary technology.

According to an e-mail sent out by his company, I-TEC, Saint sustained a "paralysing injury" to his spinal cord on Tuesday morning while testing "an experimental wing mounted to a vehicle".

The message continued, "Right now, Steve has no control of feet or hands, but his mind is clear and he does have some motion and sensation in all four limbs.

"Steve's ministry theme for the last decade has been 'Let God Write Your Story.' Shortly after being flown by helicopter to Shands Teaching Hospital at the University of Florida in Gainesville, Steve told his family, 'Let's let God write this chapter, too.'

"Steve's career as a stunt pilot (End of the Spear) is past. This may end his career as a test pilot for the Maverick."

The statement said that the injury would mean that Saint's wife, Ginny, will have to "wait on him hand and foot".

"Let's continue to pray for Steve and his family as they continue to walk His trail."

A later posting on Saint's Facebook page says, "Steve was conducting a test on a small aluminum airfoil mounted on a rolling test stand when it became unmounted and struck Steve in the head causing cuts to his head and resulting in whiplash.

"Currently, he has very limited movement capabilities in his arms and legs. Doctors suggest surgery in a few days to help relieve swelling around his spine.

"This accident was not Maverick Flying Car related, a car or an aircraft accident."

Saint was the founder of the Indigenous People's Technology and Education Center to build on the vision of his MAF missionary-pilot father, Nate Saint.

In 1956, Nate and four other missionaries envisioned taking the gospel to a tribe in Ecuador. But soon after successfully contacting the tribe, all five men were speared to death. Their story - most famously recounted in the book Through Gates of Splendor - is perhaps the most chronicled missionary account of the past 100 years.

It was also powerfully told in the 2006 docudrama, End of the Spear, which recounted the story of Operation Auca, in which five American Christian missionaries attempted to evangelise the Huaorani (Waodani) people of the jungle of Ecuador. Based on actual events from 1956 in which five male missionaries were speared by members of the Waodani tribe, the movie tells the story from the perspective of Steve Saint, and Mincaye, one of the tribesmen who killed the missionaries. The two eventually formed a bond that continues to this day.