Empire Flying Boat photos

Boeing 314 maintenance visits to Baltimore were required every 120 flying hours. As you say, for specialised work on the engines (Wright Cyclone 579C14AC1), so perhaps that should have been "running hours"? However, I don't think recording was that sophisticated, and I've always seen it quoted as flying hours. This seems to have meant roughly every two months in practice, although it's difficult to give a meaningful average as the boats went all over the place, and scheduling them to be in the right place to undertake an Atlantic crossing at the right point in their maintenance cycles must have been quite an art. I hadn't heard that the final legs were non-revenue, and looking at the records there are a number of very long flights to and from Baltimore, direct from as far away as Lagos, so I doubt it - they'd have made too much of a dent in the 120 hours. BOAC did have a small aircraft stationed at Baltimore the precise purpose of which seems to have been unrecorded (officially a Beech 18, but I believe they were not above "liberating" the odd Hudson from the trans-Atlantic delivery stream for use as a run-about). I think, but so far have no actual proof, that one of the uses of this was for onward carriage of passengers and freight from Baltimore,and obviously also bringing them to Baltimore.

RFS Liberators flew trans-Atlantic to Newfoundland (then still a separate country), then on to Canada. Once at Montreal, maintenance and operation further east or south were the responsibility of TCA, only reverting to BOAC operational control for the return trans-Atlantic leg. I have never seen full records of such flights, but I'm told RFS Liberators flew down to New York and Washington from time to time, and sometimes further afield, including occasional visits to various Consolidated aircraft factories. This was another area where "borrowed" Hudsons seem to have had a role, so perhaps the lack of official records was deliberate!

The interesting letter you attached was a fare quote. So far as I am aware, there were no published fares during much of the war, but there was no one single cut-off date when the previously published fares became invalid - it depends which individual station you're considering. As a broad concept, though, the Government took overall control and seats were allocated in Whitehall for the prosecution of the war and nothing else. Military demands and the cut-and-thrust of war meant that quite regularly blocks of seats that had been allocated for a particular purpose were not needed, and these were released to the airline to use on a commercial basis. Even if there were unallocated seats, the release rarely came more than a week in advance of the flight, and sometimes less than 24 hours. So each station had a waiting list, trying to connect people with places they wanted to go, and generally not specifying exactly which route they'd take. If you managed to get on to the list (I believe subject to Government vetting), could be contacted in time and were available to travel when they offered, off you went - provided the Government agreed that you had that seat on that day. Difficult to arrive at a publishable fare on that basis, so they just quoted when asked.

I'm sure there was a continuing fare structure, Mick, but nothing was published. "Price on Application", style of thing. All pooling of routes and interchange agreements were suspended for the duration And every commercial passenger, whether travelling to and from a neutral country or not, was vetted first.
Mail carriage was entirely under Government control. BOAC made no direct charges for carrying it, but collected a Government subsidy. They just did what they were told.