One of my classmates back in grad school flew with the RAF back in the late 70s and early 80s. He had many interesting stories to tell! One of his squad-mates was given the task of flying a 4-engine prop plane (cargo hauler, sorry I don't know the model designation) from jolly Olde England over to Canada, to deliver it to an air-base in Nova Scotia. This plane was outfitted with a system in which a small portion of the hot exhaust gases could be diverted to the leading edge of the wing to mitigate ice formation. This plane was also rather old. Well, the flight across the pond went uneventfully, until he got to within a couple hundred miles of the Nova Scotia coastline, when he noticed that he had less fuel left than he thought he should have. Given the age of the plane, and the probability of a faulty fuel gauge (i.e. a stuck sensor), he didn't give it much more thought. Then he noticed that the fuel level was dropping noticeably as he flew along. He radioed ahead and told them of his predicament and requested priority for landing, as his fuel reserves were now quite low. The air-base cleared the runways of all traffic and had emergency crews stationed along the primary landing strip just in case he had to make an emergency crash-landing. Turns out the landing went just fine, he taxied to a stop and the wings were literally dripping fuel onto the tarmac. Long story short -- it turns out that the aging exhaust system had rusted out and collapsed, diverting virtually ALL of the exhaust gases into the interior of the wings, where the fuel was held in rubber bladders, the ancient rubber had melted/cracked under the heat load, and the fuel was spilling out. The ATC said he looked like the World's Biggest Crop-Duster on final approach. Nigel told me that his buddy got a bill for $17 million pounds from the Crown (he framed it and hung it on his wall).