In a report to be published on Tuesday more than 30 head teachers complain of the havoc caused by Tornado fighters flying at 500 mph as low as 250ft overhead - sometimes less.
Figures in the report, produced by a Leeds University researcher for the anti-low-flying pressure group Freedom of the Skies, show that the noise level from a jet at such a height is equivalent to 50 pneumatic drills. It cites German research which found that low flying raised blood pressure in young girls, increased irritability among the over- forties and caused hearing problems among young children.
One Welsh head told how a member of staff dived for cover under a table when she saw a Tornado coming towards the school. A second said his pupils always cover their ears and run for cover when the planes came over. Seventy per cent of primary school heads said their children were frightened and 25 per cent said classes were disrupted.
Gethin Thomas, head of Nantgaredig primary school, near Carmarthen, said: "Low-flying aircraft go over the school at least three times a week. The majority of the children are very frightened when this sudden noise comes without any warning. Children run to any corner they can find to get security and put their hands over their ears. Once we were eating lunch in the staff room, which has a view down the valley, and a member of staff saw a plane coming towards us, shouted 'It's going to hit the school' and dived under the table."
Bethan Thomas, who lives near Carmarthen with her three children, said: "The noise is so loud and horrible. It leaves my children shaking. They are also very anxious and will not go out of the house to play."
Gillian Metcalf, a Freedom of the Skies organiser, said: "People are desperate to find a solution. We hope that our report and a realisation of the health effects will have some impact."
The Leeds research, carried out by Dr Lorna Fewtrell and part-funded by the Joseph Rowntree Trust and some councils, is the most comprehensive report yet on the effects of low flying in the UK.
Britain, which has the lowest limits in Europe, has become the main low flying exercise area for Nato aircraft from the US, Germany and Belgium as well as the RAF. In 1990 Germany barred sorties below 1,000ft.
Around 85,000 low-flying sorties are carried out every year. Jets can fly as low as 250ft at a maximum speed of 517 mph over large areas of Britain. But in south-west and north-west Scotland and central Wales, the report's study area, fast jets are allowed to descend to 100ft.
According to the report, defence consultant Malcolm Spaven found that pilots often went below even these limits. One flew at just 63ft.
Mr Spaven said: "The available evidence suggest that height breaches by low flying aircraft occur regularly. It also suggests that combat professionalism and environmental responsibility may at times be in conflict."
Last year there were 5,778 complaints about low-flying in Britain. In the first nine months of this year there were 5,236.Reuse content