A statement from Bond Air Services said: "During normal operations yesterday, one of our EC135 fleet has experienced an indication defect that requires further technical investigation.
"Therefore as a precautionary measure we have temporarily suspended service operations whilst we undertake detailed diagnosis.
"We commenced investigations overnight, are continuing this morning and are in close liaison with Eurocopter regarding this investigation."
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Dry but breezy tonight, cloud and some bright spells on Sunday.
Dry but breezy this evening and overnight with cloud and sunny spells tomorrow.
Mostly dry with sunny spells and a fresh south-westerly breeze.