'I'll do some slow passes for you," promises Wing Commander Ken Wallis, wheeling from his shed a contraption that looks rather like a bicycle with a propeller on top. In a shirt and tie and with his white hair rakishly slicked back, the 94-year-old hops on to a narrow seat below the rotor and straps an ineffectual-looking safety belt around his waist. "Stand back. I don't want anyone walking into the propeller and damaging it," he barks and his self-built autogyro, Zeus III, roars into ear- splitting life.

Hunched over the controls of this miniature magnificent flying machine, Wallis taxis past his fine Georgian house and into a field of buttercups, where man and machine are thrown into the sky as if plucked away by an invisible hand.

Whizzing demonically across the wide Norfolk sky as free as the swifts darting above him, Wallis turns and hurtles low over his airfield. He throws a few "look no hands" poses, slipping both legs coquettishly over one side of his machine, gives a thumbs up and then regretfully brings Zeus III back down to earth. "I'm sorry, I probably flew over 70mph for a moment. I didn't notice the speed limit," he says impishly, hair still immaculate. Despite the absence of helmet and goggles, his eyes are not even watering.

If a screenwriter invented Wallis they would be told to come back with a more realistic character. Part Biggles, part Captain Flashheart and part Doc Brown, Wallis's life as an inventor and flying ace has seen his involvement in all kinds of historic moments from the 20th century – the second world war, the hunt for Lord Lucan, the atom bomb, the Loch Ness monster, the cold war and the invention of Concorde. He takes his autogyros to heaven and back as often as he drives his car, and last month celebrated the centenary of the first recorded flight of the "Wallbro monoplane", built and piloted by his father and uncle with a party at the aviation museum in Flixton, Suffolk. (Wallis regularly flies to the museum from his home.) After they witnessed the Wright brothers' first flight in France in 1908, the Wallis brothers hoped to win a £1,000 prize for the first all-British aeroplane. They missed out by a couple of months but still took to the skies in their innovative flying machine. Wallis inherited "the family vice": a love of speed. But he also wore an eye-patch over what he casually calls his "defective eye", in which he has very limited vision.

In 1936, this impairment led to his rejection by the RAF. Undeterred, Wallis customised and sold a "rather racy" Bentley car and spent the money training for his pilot's licence. Tested again after war broke out in 1939, Wallis sneaked a look at the bottom line of letters on the test chart with his good eye when the doctor glanced down at his notes. He cheated, and passed. "I've been very lucky," he grins.

Hanging in the hall of his home are a mangled piece of metal and a parachute ripcord: "my Wellington that I left in a hurry in 1941," he explains. He had been dispatched on a bombing raid of Frankfurt but it was too foggy to see the military targets so the bombers were instructed to fly home. Returning with this extra weight, they ran short of fuel. Before his bomber crashed in Lincolnshire, Wallis and his five crew bailed out. They all survived, although three other Wellington crews perished that night. After surviving another wartime crash when his plane was struck by lightning, Wallis applied to fly Mosquito bombers at night. This was a big mistake. His night vision was tested and "all hell let loose – 'you've been flying with a bomber crew and you can't see properly!'"

He was sent to the RAF's top medic. "He said, 'Wallis, I'd rather have a man with a bit of fire in his belly who wants to fly than some of the perfect specimens I get here who don't.'" And Wallis carried on. Seconded to America at the height of the cold war, he flew B-36s laden with nuclear bombs over the North Pole. "That was a creepy business," he admits.

While in the States, he discovered designs for the autogyro and set about building his own. Unlike a helicopter, an autogyro's overhead rotor is unpowered, and air flowing through it causes it to rotate, which provides lift. Thrust is then supplied by the engine-powered propeller at the rear. In flight, autogyros are a bit like an ultra-mobile miniature helicopter, as James Bond demonstrated in You Only Live Twice. In one of the most memorable Bond scenes, Sean Connery unpacks "Little Nellie" from a couple of suitcases and fights baddies in orthodox helicopters, zipping around an active volcano in Japan. Little Nellie was also built by Wallis and named after him (during the war, anyone called Wallis or Wallace was nicknamed Nellie after the 1930s musical hall star Nellie Wallace) and the James Bond at the controls in the film is, of course, Wallis himself. He still has 19 working autogyros he built himself in his cavernous shed, jostling with a treasure trove of other inventions and bits and bobs salvaged from German jet engines. One autogyro will take a passenger and another is so quiet that Concorde engineers visited him in the 1970s to discover his noise-reduction techniques.

During the 70s, he worked for a radar company that pioneered a type of aerial photography that could detect where bodies were buried. Wallis was dispatched to hunt for Lord Lucan over the Sussex Downs, and to Devon to look for a missing mother and two children. He was also employed to scan Loch Ness for the monster. If he has a regret, it is that no company ever produced his autogyro for the mass market. "These are aircraft that can do useful jobs," he insists.

Wallis has crashed his autogyros a few times but he insists they are perfectly safe: "I feel rock-steady on them." Despite his scrapes, the only thing he has broken is numerous records. Wallis has flown an autogyro at 18,976ft. He has piloted an autogyro the length of the British Isles. Now he wants to break his own 129.1mph world speed record for an autogyro, which he set aged 89. He is aiming for 140mph. The problem is red tape: the Civil Aviation Authority has ruled that certain types of autogyro mustn't exceed 70mph, and Wallis's machine must be flown by one of their test pilots first. He hoped to celebrate the centenary of his father's flight with a new record but feels defeated by these regulations. You sense nothing will stop Wallis, though: if the CAA won't change its mind, he hopes to take his machine abroad. "I might have another go, but it's such a business to lay on the official timekeepers. It's a bit easier when you're Richard Branson."

Whether he gets a new world record or not, it would take a hard heart to deny Wallis his freedom to fly. A widower, he lives alone with his magnificent machines but dines with his daughter, who lives nearby, every other night. Does he have anyone to whom he can pass on all his incredible engineering knowledge? "No, not really. It's a shame," he says, sounding sad for the first time. But the sharp eyes of Wing Commander Ken Wallis – one perfect and the other faulty – still do not water.