I quite agree. It is sad that the aviation officials of the UK are so against Daks carrying passengers. They've been going for 60 years - why is the situation so different now
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You probably know Ralph Burridge, who was telling me recently that Aurigny used to shut down an engine whilst loading pax sometimes. Was all far too complicated but I hear that on the series 400 the problem has been overcome (would love to know how - probably one of the ways you mentioned) and on older varients there are ways around it.