Playing devil's advocate...
DTV has scheduled service to 2 destinations year round, 1 weekly summer only and a few weekly charter seasonal. At 165,000 pax per year, excluding offshore islands and remote locations, it has close to the lowest number of passengers of any UK airports. DTV also tries to run fire training and scrapping of old worn-out aircraft. The airport also offers secure caravan storage.
We thus have an airport dabbling in quite a few different businesses but not having any significant size in any of these areas. Typically a company thst succeeds will pick the areas it thinks will do well and focus on them. Passenger service, fire training, aircraft scrapping and secure storage are too many unfocussed areas for a modest company like DTV to be trying. Perhaps better to pick a couple of business areas and focus energies on those and ditch the areas that incur costs and have little prospect of long term growth or profitability.
Charter may have a place in DTV but there is a need to demonstrate the benefits and logic. Perhaps someone could make a clear business case for the various activities at DTV