London — Much of British industry may be in trouble, but in air and space technology the story is entirely different. This year's Farnborough Air Show gave Britain's planemakers their biggest boost for a decade or more.
Among achievements notched up during their annual window display:
* Generous praise from US Secretary of the Air Force Hans Mark for the Harrier jumpjet and a prediction that Britain will lead the way into the 1990s in providing vertical takeoff and landing (VTOL) fighters.
* A $:200 million ($480 million) contract from the US Air Force to buy British Rapier antiaircraft missiles to defend seven large American air bases in Britain.
* A successful bid by a British consortium to provide NATO defenses with early warning devices capable of spotting hostile air movements 200 miles beyond the ground horizon.
Mark's support for Harrier-type combat planes is seen by captains of Britain's air industry as highly significant. The Air Force secretary said Britain had a substantial lead over the rest of the world in jumpjet technology.
At present the USAF is considering two types of VTOL fighter: the AV8B being built for the US Marines, and the RAF's GR-5. The implication of Mark's comments is that the USAF is likely to opt for the British plane.
But even more important is the fact that British aircraft companies are already well ahead with the development of a supersonic jumpjet, and this clearly impressed US officials.
Future wars, it is believed, would require fast-flying planes capable of operating from pocket handkerchief air- fields. Supersonic VTOL fighters would meet the requirement, and it is here that the British are forging ahead.
Asked to explain why British aerospace technology is so far advanced when other aspects of industry are languishing, local aircraft manufacturers point to strong and consistent government support, a readiness by separate firms to merge into larger concerns, and the use of sophisticated selling techniques in the highly competitive international market. The result has been a bumper year for the British industry. Sales will earn $:1.2 billion ($2.9 billion) in foreign currency.
Speaking at the Farnborough Air Show, Prime Minister Margaret Thatcher praised the aircraft builders and then, typically, told them they could do better.
The rising curve of Britain's aerospace performance is the kind of development that gladdens the heart of Mrs. Thatcher and her ministers. Their philosophy involves a "shakeout" of British industry -- a readiness to drop old, unprofitable technologies and replace them with modern products the world wants.
That's exactly the philosophy that has got the planemakers off the ground and soaring above an otherwise bleak British industrial landscape.