MAGNIFICENT MEN IN THEIR FLYING MACHINES: Yorkshire aviation pioneers in the spotlight at air museum open day

The Yorkshire Air Museum at Elvington has a full-sized replica of the aircraft in which, in 1853, Sir George Cayley's coachman, John Appleby, took to the air at Brompton Dale up on the North York Moors for the first manned heavier-than-air flight in history.

It is an astonishingly flimsy craft - a great overhead sail made of linen stretched like the wings of a bat across a frail wooden frame; a crude rudder at the end of a long tail; and, suspended beneath the sail on a series of wooden struts, a small three-wheeled undercarriage.

The aircraft is actually a replica of Cayley's 1852 craft, rather than the history-making 1853 version - no drawing of the later craft has ever been found. But the version at the air museum is presumably close enough to that in which Mr Appleby made his historic flight.

There's a wonderful description of that flight in Brian Catchpole's book Balloons to Buccaneers, based on a record left by Cayley's granddaughter Dora, who was ten at the time.

The entire village gathered on the dale to watch Sir George's coachman clamber into the fuselage of the flyer. Everyone expected the machine to soar into the Yorkshire skies and the villagers thronged the high east side of the dale, pressing forward to get a good view.

The replica Cayley Flyer suspended from the ceiling of the main hangar at the Yorkshire Air Museum

But Dora describes how she thought the flyer 'came down in rather a shorter distance than we expected. The coachman got himself clear and, when watchers had got across, he shouted "Please, Sir George, I wish to give notice. I was hired to drive, and not to fly"'.

Mr Appleby may not have been made to fly. But the replica Cayley Flyer at Elvington certainly was. Whenever it is moved out of its hangar at the air museum it tugs impatiently, wanting to lift off in response to the lightest breath of air, says museum spokesman Ian Richardson.

This very replica did actually take to the air. In the 1970s it made a successful flight for a TV documentary up at Brompton Dale on the North York Moors - where Cayley's coachman made that original flight. This time it was a man called Derek Piggott in the cockpit. It must have been scary, committing your soul to the heavens in such an insubstantial craft - though not nearly as scary as for Sir George's poor coachman 120 years earlier...

Regular visitors to the air museum will have seen the Cayley Flyer hanging suspended from the ceiling. But there's nothing quite like seeing it up close.

It really is more like a modern hang glider than anything - hand built out of wood and linen, with a huge overhead sail and three small wheels on the undercarriage that look remarkably like modern bicycle wheels.

Cayley referred to it as his 'governable parachute' - and the important word there is 'governable'. The Yorkshire aviation pioneer had been inspired by the hot air balloon exploits of the Montgolfier Brothers. "But the thing about their balloon was that it could go up and down, but you couldn't control the direction in which it went," Mr Richardson says. "Cayley wanted to design a machine which would go where humans wanted it to go."

Sir George Cayley

He devoted much of his life to that. He first sketched designs for heavier-than-air helicopters and 'flying machines' in the 1790s, began experimenting with model gliders in 1804, and by 1809 had published an article on heavier-than-air flight. On Aerial Navigation, was the title of that paper, published in the Journal of Natural Philosophy. "I feel perfectly confident that this noble art will soon be brought home to man's general convenience, and that we shall be able to transport ourselves and families, and their goods and chattels, more securely by air than by water; and with a velocity from 20 to 100 miles per hour," he wrote. Far sighted or what?

Cayley was the first to understand the principles of aeronautics, experimenting with sections of wing at his home at Brompton Hall until he discovered the principles of lift and drag. He really wanted to develop a fixed-wing, powered aircraft - but in many ways he was too far ahead of his time, says Mr Richardson. The internal combustion engine was decades away, and steam engines were far too heavy. Cayley did try to develop an engine in which the piston was fired by a gunpowder explosion - but sadly, without success.

So it was ultimately in an unpowered glider that he conquered the skies. But years later, in 1909, none other than Wilbur Wright himself acknowledged his debt to Cayley. In a speech to the Aero Club in London, Wright said: "About a hundred years ago an Englishman, Sir George Cayley, carried the science of flying to a point it had never reached before."

Cayley, in short, was a true aviation pioneer - one of the great figures in the history of man's conquest of the skies.

So it is only right that the replica of his flyer should be one of the centrepieces of a special 'Pioneers of Aviation' day at the Yorkshire Air Museum this coming Sunday (August 20).

It will be brought down from its roost high up under the ceiling and wheeled into place in a prominent spot in the main hangar, so that visitors can see it up close for themselves.

Gary Hancock, in Royal Flying Corps uniform, stands next to the Blackburn 1912 Mercury at the Yorkshire Air Museum

The Cayley flyer will be joined on the hangar floor by a replica of another pioneering early aeroplane: Robert Blackburn's 1912 Mercury monoplane. This had been test-flown on the sands at Filey, before being shown off at an international flying meeting in Blackpool. It became the first successful all-British aeroplane, says Ian Richardson. A dozen or so were manufactured, and within a few years Blackburn had built a new aircraft factory at Brough in East Yorkshire, where BAE Systems still have a base today.

Like the Cayley flyer, the Mercury monoplane replica normally hangs from the ceiling of the main hangar at the Yorkshire Air Museum. But on Sunday it, too, will be brought down to the hangar floor so that visitors can see it up close.

And a beautiful aircraft it is: built entirely out of wood, with wings of treated linen stretched drum-tight over a wooden frame. It, too, is surprisingly light - it can easily be manhandled by three people. The open cockpit has a leather seat - and a miniature steering wheel.

In addition to these two beautiful aircraft, the air museum will be 'firing up' four of its other early aeroplanes on Sunday - not flying them, but letting their engines have a good run.

Two of these are First World War biplanes - the and the Royal Aircraft Factory SE5a. The Kitten is a tiny aircraft - an experimental flyer designed to be launched from a platform on a battleship to intercept zeppelins and then ditch in the sea.

The Eastchurch PV8 Kitten at the Yorkshire Air Museum

It never actually went into production, but the SE5a did, proving itself as a fighter in the last years of the war. The other two aircraft date from the Second World War or after: the museum's 1944 Douglas C-47 Dakota and the 1947 De Havilland Devon twin prop, used by the RAF after the war as a VIP transport aircraft. To top everything off, there will also be a flypast on the day by a Douglas Dakota, a Hawker Hurricane and a Supermarine Spitfire from the Battle of Britain Memorial Flight.

The main stars, however, will surely be the Cayley flyer and the Blackburn monoplane.

It is very rare that they're brought down to ground level, says Mr Richardson. "They are normally suspended from the hangar roof due to space restrictions, so this is a rare opportunity to get a good look at these fabulous examples of early aviation."

One not to be missed...

• The Pioneers of Aviation day at the Yorkshire Air Museum at Elvington runs from 10am-5pm (normal museum opening hours). Normal entry fees apply: £10 adults, £8 concessions, £5 children and family ticket for £26.