It's been suggested that a thread I kicked off on Military Aircrew might have a better home here. The original thread can be seen here:
http://www.pprune.org/military-aircr...underland.html
The post that kicked it off was:
A recent visit to Oban prompted a few thoughts about the wartime operations of the Short Sunderland from there. The central question is this: what length of water did the Sunderland routinely need to land and, especially, take off in?
The main base for RAF Oban was on the island of Kerrera, on the west side of Oban Bay. Oban Bay is less than a mile across (pretty much however you measure it). Did/could the Sunderlands take off and land within Oban bay, or did they have to head out beyond Kerrera to do so? The latter seems a possibility as there was a secondary maintenance base at Ganavan Bay, around the corner to the north.
Incidentally, the RAF Oban memorial at Ganavan is worth a visit, despite being overshadowed by a new and very upmarket housing development right next to the public car park and beach.
The landing and take off runs of the Sunderland also have a bearing on the theoretical possibility of a long standing conspiracy theory about the loss of Sunderland W4026 on 25 August 1942 while carrying the Duke of Kent. Officially this was bound for Iceland, and took a wrong heading in cloud. You don't have to look far to find theories that suggest it was instead going to Sweden for peace talks, and was intending to land on Loch More in the far north of Scotland to pick up Rudolf Hess en route, when it crashed 11 miles to the south...
Seems to me that fundamental to the theory is the question of whether it was a viable proposition for a Sunderland to land, and then take off, from a loch with a clear run of over (but not much over) 1.25 miles. This is actually rather more than is available in Oban Bay, and the surrounding landscape seems much flatter than than at Oban, which seems relevant given the Sunderland's noted lack of climbing ability. So setting aside the likelihood of this theory actually having any substance, how viable would it have been from the point of view of the performance of the Sunderland?