A Review of the Severe Lightning Threat 2001-01-2888
The CAA has previously initiated and funded research to assess the lightning threat to helicopters operating in the North Sea.
One of the conclusions of this research is that lightning strikes to helicopters operating in the North Sea are more likely to involve positive polarity cloud-to-ground strikes which generally have a higher action integral than the typical negative polarity cloud-to-ground strikes.
The UK-CAA is also familiar with a lightning accident to a glider North of London in 1999.
One of the conclusions of the investigation into this accident was that the glider had been struck by a lightning strike with a considerably greater action integral than the present certification test threat level.
EUROCAE WG31 and SAE Committee AE2 have reviewed the above data and other incident/accident reports. The available data on the severe threat is considered limited, the committees therefore requested that further evidence be presented.
The EUROCAE WG31 Committee therefore took an action to collate examples of lightning strikes where the damage observed has been reproduced in the test laboratory or has been quantified by other means.
These examples have been collated into a database of severe threat incidents.