KEY POINTS:
SYDNEY - A blind pilot is about to enter the record books by achieving the seemingly impossible - flying a microlight aircraft from Britain to Australia.
Miles Hilton-Barber, who describes himself as "blind as a bat", will become the first blind person to fly halfway across the world
when he lands in Sydney at the weekend.
The 58-year-old Briton flies with the aid of specially designed "talking" navigational instruments, which help him plot his course.
The voice output technology has been applied to the customised aircraft's altimeter, wind speed meter and compass. He punches flight co-ordinates into a wireless keyboard strapped to his leg.
"It's a very primitive form of flying, but for a blind man it's wonderful because it is very sensual," he said on Tuesday. "You can smell the smells coming up from the ground and I can feel the temperature, the wind, the cold."
During the journey Hilton-Barber has been accompanied by a co-pilot, microlighting champion Richard Meredith-Hardy, but he only takes control if the pair encounter an emergency.
Hilton-Barber, of Derby, began his 22,000km journey on March 7 when he took off from Biggin Hill airfield, outside London. His journey has taken him across Europe, the Middle East, India and Southeast Asia, following the route of the classic 1919 London to Sydney Air Race.
The father of three hopes to raise £1 million ($2.7 million) for a campaign to eradicate preventable blindness in developing countries.
On Sunday he took off in his Pegasus Mainair microlight from Kupang, West Timor, Indonesia, and landed a day later in Darwin, the capital of Australia's Northern Territory.
Yesterday he flew to the outback mining town of Tennant Creek in the Northern Territory. He will then cross into Queensland and follow the coast south to Sydney.
"We stay in sight of roads because if we had engine failure over the Outback it would be very serious," he said. "So far the aircraft has been totally reliable."
Hilton-Barber, a motivational speaker, lost his sight by the time he was 30 as a result of a rare hereditary disease.
"I used to see my blindness as a disability. But in 1998 my brother, who is also blind, sailed solo from Durban to Fremantle. After that I saw blindness as a challenge. I'm still blind as a bat but I'm a very happy bat. I've achieved far more than when I had my sight."
Brought up in Rhodesia, he tried to join the Royal Air Force as an 18-year-old but failed the eyesight test.
"They told me I'd never fly but 37 years later I've just flown over 10 and a half thousand miles around the world."
There have been several terrifying moments during the journey. Flying over the mountains of Lebanon, the pair were caught up in an ice storm. "We had ice all over our flying suits."
In Saudi Arabia, desert thermals sent the tiny aircraft rocketing up into the sky.
"We were knocked sideways and thrown upwards at a rate of 1500 feet (457m) a minute - the equivalent of being in a lift going up three floors a second. You just have to not panic and keep going."
During a tropical storm in Malaysia, they were forced to fly so low that they almost crashed into a cliff.
"It was like flying through a waterfall. The rain was so hard it was like someone firing gravel from a shotgun. We knew it was a life-threatening situation."
For every pound Hilton-Barber raises, Standard Chartered Bank will match it.
"I will never see again but the next best thing is to give someone else the gift of sight," he said.
"There are 28 million blind people in the world who could see tomorrow if the money was available."
Eye for a challenge
Miles Hilton-Barbers adventures so far:
* Attempting to become the first blind person to reach the South Pole, in the process man-hauling a sledge more than 400km across Antarctica.
* Completing "the toughest foot-race on Earth" - 400km across the Sahara Desert in the Marathon des Sables
* Climbing to 5300m in the Himalayas.
* Climbing Mt Kilimanjaro and Mont Blanc.
* Running an 11-day ultra-marathon race in China.
* Completing the "coldest marathon on Earth" - the Siberian Ice Marathon.
* Setting Malaysian Grand Prix lap record for a blind driver in a Lotus.