The Braer grounding prompted an increase in emergency cover but recent cutbacks have left one emergency tug for the whole of Scotland.

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The grounding of all non-emergency flights from England's airports - which began on Thursday morning - will remain in place until at least 0100 BST on Monday as the plume continues to drift across Britain.

BBC: Flight ban 'not over-reacting' say Wiltshire scientists

The ANA plane was forced to make an emergency landing, and that led to the grounding of all Dreamliners in operation.

BBC: Boeing 787 Dreamliner: NTSB details battery fire

The official report into the incident said that while an emergency salvage tug would not have prevented the initial grounding it would have made it possible to secure the vessel more quickly.

BBC: Tug plan marks Empress disaster

Fears about battery safety emerged after a lithium-ion battery in a 787 operated by All Nippon Airways overheated, forcing an emergency landing in western Japan in mid-January and a worldwide grounding of the Dreamliner fleet.

BBC: Boeing 'set to offer plan to fix Dreamliner battery'

Not that Boeing is publicly jumping on any scapegoats to wholly blame for the worldwide grounding of its 787 Dreamliners after the Federal Aviation Agency ( FAA ) issued an emergency airworthiness direction (AD) in response to a battery fire that forced an All Nippon Airways plane to make an emergency landing in Japan on January 16.

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