Colin
In your opening post you say that your father flew from "Foyle" to Accra and onwards. I think that this is very unlikely as Loch Foyle is at the extreme north end of the island of Ireland. The main base for flying boats operating such services during WW2 was at Foynes in the Shannon Estuary in the Republic of Ireland (despite "neutrality"). BOAC had a crew base there as did the American crews operating the transatlantic flying boat service to Newfoundland and onwards. There is a very good flying boat museum in the port of Foynes - well worth a visit if you are ever in the area.
Ian BB