Blimp maker comes down with a bump: The manufacturer of the world's smallest airship is up for sale, but still has high hopes. Robert Cole reports

THE oldest form of human flight has not advanced substantially since the Montgolfier brothers put a sheep, a chicken and a duck aboard the world's first hot air balloon in 1783.

Two centuries later the balloon, and its cousin the airship, still does little more than float up, around and down. But that does not stop an apparently endless succession of entrepreneurs trying to make serious money out of developing new types of blimp for new-fangled applications.

The airship, blimp, zeppelin or dirigible - a synonym derived from the French word diriger meaning to steer - has a chequered history. This week another chapter closes.

Thunder & Colt, a balloon maker based at Oswestry in Shropshire, has put its airship-making arm up for sale. Malcolm Gillespie, the managing director, says his company does not have the capital required to find markets for its GA42 airship.

The firm is one of two operating subsidiaries of Airborne Industries, an unquoted company, 80 per cent owned by institutions. It has spent pounds 3m developing the GA42, the world's smallest blimp. It is 60 feet long, 25 feet wide and holds 42,000 cubic feet of fire-resistant helium. It carries a pilot and one passenger and is powered by an engine the size of a large lawnmower. It zips along at 30mph and can climb 1,000 feet a minute.

Crucial to the attractiveness and possible success of the business are certificates from the UK Civil Aviation Authority and the US Federal Aviation Authority giving the GA42 the seal of airworthiness. 'The certification is what makes this business special,' says Mr Gillespie. 'Most airships have been built by enthusiasts, dreamers, and do not reach the certification stage.'

GA42 - the initials stands for gas airship and the 42 refers to the helium cubic footage in thousands - is dwarfed by Goodyear's 280,000 cubic feet of airship commonly seen drifting above motor race meetings. The largest American blimps contained 6.5 million cubic feet of gas.

Mr Gillespie boasts that the GA42 is the world's cheapest airship. But retailing at pounds 360,000 apiece, it is a toy for the richer-than-average adrenalin freak. Thunder & Colt also planned to develop a more cost-efficient GA42; operating costs are still high at pounds 60,000 a month. A good chunk of this money is spent on the pilot and the seven ground crew needed to bounce the blimp into flight and catch the mooring lines to bring it to a halt.

In addition, helium is a rare and expensive gas: filling the relatively small GA42 costs pounds 3,000. Consequently, once inflated blimps usually stay inflated. That brings parking problems, and extra costs.

To ride in the GA42, slung in a capsule below the helium-filled envelope, is an unnerving experience. Even in relatively light breezes the bubble is blown and buffeted.

You feel vulnerable. You think: 'What if a bird with a sharp beak pops the balloon?' and 'What if the pilot drops dead?' 'Are the fasteners holding the cockpit in place safe?' or 'What happens if a storm suddenly whips up?' and 'It is a long way down and I haven't got a parachute.'

The airship is caught between the manoeuvrability of a helicopter and the stability of a plane. It has the speed of neither. It is like a scary but exciting fairground attraction.

History has shown that airships are not suitable as passenger vehicles. In fact it is hard to envisage any practical use for them other than as advertising hoardings or for peacetime surveillance, classically as platforms from which to televise outdoor sports meetings.

Mr Gillespie reckons he can get pounds 2m to pounds 2.5m for the business, probably selling to a firm in the US, where blimps - the American name - are most often found.

Thunder & Colt's two prototype GA42s - at a knock-down price of pounds 270,000 each - are included in the sale package. Also negotiable is the purchase of a portable 11,000sq ft hangar: pounds 100,000 new but now available for pounds 49,000.

Mr Gillespie admits that an airship has limited usefulness. 'It is a flying billboard.'

He can only hope there are buyers with vision and courage. The history of the commercial airship provides discouraging precedents.

Airship Industries, with the help of the now bankrupt Australian Alan Bond, created excitement through the middle of the 1980s. It set itself up as a serious defence contractor hoping to take advantage of interest from the United States military. The Pentagon thought, and is still thinking, about ordering dozens of blimps for use as surveillance platforms and to house early warning equipment.

Airship Industries, however, collapsed into receivership with debts of pounds 50m in September 1990. Its end was ignominious but it lost reputations and money rather than lives.

Attempts early in the century to establish passenger-carrying inter-continental air links with hydrogen-filled zeppelins ended in the flames of the R101 and the Hindenburg.

The colourful and brave promoters of the latest airship venture will need all the help they can get.

(Photograph omitted)