Carl Schwamberger wrote:Bunker & Fuel Oil No. Six
Indeed Carl, there are any number of sources that have been quoted over the years indicating the difficulty of getting Bunker C to ignite, its lack of vapor, and so on, all of which has been ignored, so I'm not sure of the utility of posting more I'm afraid?
It all comes down to the breathless exclamation "but Pembroke dockyard!", usually associated with various random - and usually incorrect - factoids (no, the exterior roof of a oil tank doesn't "float", but there is a floating interior "roof" normally found in those containing volatiles), assumptions (aircraft can carry all the bombs they can carry simultaneously), and leaps of faith (American naval officers routinely, stupidly, and culpably ignore maintenance of vital installations such as oil storage tanks, allowing them to become "rusty and corroded"). Curiously though, the Admiralty Oil Fuel Depot Pembroke remains an anomaly. In fact, at least two other AOFD's were bombed: Plymouth on 28 November 1940, which ignited one tank that wasn't suppressed until 1 December and Invergordon on 17 February 1941, which destroyed one tank and damaged another...but neither ignited. At Invergordon, the first tank held 4,000 tons (two-thirds full, assuming the standard Admiralty 6,000-ton tank) and about 2,000 tons "escaped over the bund wall into a railway cutting", while the second held 6,000 tons "most of which leaked away into the compound" of which 2,500 tons wasn't recovered (WAR CABINET OIL POSITION Monthly Report for February, 1941, submitted by the Secretary for Petroleum, p. 3). Examination of further Oil Position reports likely would reveal more cases, but given that none other than Pembroke caused any great notice, it is unlikely many other catastrophic cases will be identified and in any case I generally pass on tail-chasing exercises started by other posters.
Of course one point that remains unclear in all these cases is what exactly was in the tanks? The AOFD's primary role was storing bunker oil, but if the damaged tank at Invergordon "leaked" in the middle of February, then it is unlikely it contained a HFO, which simply don't flow easily in cold weather. Which could indicate that the tanks held one of the many other fuel oils, including gasoline, diesel, and other HFO's, stocked in an AOFD. So what was in the Pembroke tanks? In August 1940, another nine oil depots were attacked, none catastrophically and in December 1940 "a considerable number of incendiary bombs fell on oil installations and depots, but the damage done was slight" (WAR CABINET OIL POSITION Monthly Report for December, 1940, p. 3), and in 1941 Liverpool was hit "on the night of 7th/8th May, damage was sustained to various installations at Barton where 9 tanks were badly damaged or destroyed, and certain lubricating oil plants suffered considerably" (WAR CABINET OIL POSITION Monthly Report for May, 1941, p. 3), but no catastrophic fires again...so was what happened at Pembroke the norm or something unusual?