The Lancasters of No 617 Squadron left Woodhall Spa in the early evening of the 23rd. Their 'Tallboy' strike would be followed up by 100 further aircraft from No 5 Group. Whatever their feelings, the operation could not have been more different to the one carried out the previous year. Although thick cloud again hampered crews over the target, bombing was overall very good, though several crews returned to Woodhall Spa with their valuable Tallboy still aboard. Of those dropped at least two direct hits were made on the banks of the canal, breaching both branches. The follow up raiders did further extensive damage. On the return home Flt Lt Geoff Stout's aircraft was shot down, Stout died in the crash having seen his crew safely out of the plane. Two who bailed were killed in the jump, two were captured, and two evaded, succeeding in returning to England. On October 3rd, Tait once again flew a Mosquito when the squadron was tasked with breaching the sea wall at Westkapelle. However he arrived over the target to find it severely damaged by a previous raid, he aborted the mission and ordered the squadron back to Woodhall Spa. With Allied troops now advancing rapidly across France towards Germany, it was feared that the enemy might try to flood the Rhine Valley in an attempt to hinder progress. A critical point was the Kembs Barrage, a dam like structure which, if the sluice gates were opened,would have a catastrophic effect on ground forces. The Americans requested the Barrage be destroyed as soon as possible, to allow the water to dissipate naturally along the rivers length. On October 7th, thirteen Lancaster and their Tallboys left Woodhall Spa, the crews could not have been happy with the method of attack they were to employ. The force was split into two groups, the first seven would bomb from around 8,000 ft, "at the same time" the second group of six aircraft would drop their Tallboys fitted with delayed fuses from just 600 ft. The sky was clear as they arrived over the target, Tait dropped his Tallboy from 600 ft and it landed close to the lock gates, while Cockshott also scored an almost direct hit. There were several further near misses and with the lock gates out of action the mission was deemed successful. However the heavy flak encountered took it's toll, with Sqn Ldr Drew Wyness, having had two engines shot away, forced to ditch in the Rhine. Wyness and his crew waded ashore to be met by German soldiers and they would have assumed they were being marched into captivity. However later that day in the nearby town of Chalampe, it appears they were executed by firing squad. Also lost were Flt Lt Kit Howard and his entire crew when flack removed a wing and their aircraft crashed into woods at Efringen-Kirchen two miles from the target. Although she remained afloat and seemingly unscathed after the September operation, The Tirpitz had indeed been hit and damaged. The Kriegsmarine however decided that full repairs would be impractical, and so moved her South to Tromso, to act as a floating artillery battery. The Allies, unaware of her diminished operational state, still viewed Tirpitz as a very real threat. The move to Tromso had put Tirpitz just in range of Lossiemouth, but to extend the 'legs' of the Lancasters, extra fuel tanks were fitted inside the fuselage. Each aircraft was also fitted with new up-rated Merlin 24 engines. On October 28th, twenty Lancasters from No 617 Sq and eighteen from No 9 Sq flew to Lossiemouth and refuelled. They would be accompanied by a Lancaster from No 463 Sq, fitted with camera equipment to film the attack. They would fly over the North Sea, across Norway and over Sweden, where they would all rendezvous for the 'run in' and attack. After this they would make the several hour flight straight back across the North Sea to Lossiemouth. Taking off in the early hours of October 29th, they would be over Tirpitz as dawn was breaking, 'Operation Obviate' was on...