Most of the rest of August was a washout with few missions flown. A return to the La Pallice U-Boat pens on the 18th caused considerable damage, as did an attack on the E-Boat pens at Ijmuiden in Holland. The final mission for the month was flown on the 26th, when 617 was joined by aircraft from No 9 Squadron ( the only other squadron to deploy 'Tallboy') for anti-shipping strikes around Brest. With Britain so dependant on open shipping lanes for her supplies of food and other materials, a constant worry was the Kriegsmarine. In particular the Tirpitz, after trials in 1941 she had sailed to Norway, were Hitler intended for her to be used to defend the Norwegian coast against possible invasion. Ever fearful the ship might make for open water, the British had attacked Tirpitz several times, with RAF Halifax bombers, then Royal Navy midget submarines. A number of raids by Fleet Air Arm Albacore aircraft had been flown also, but despite minor damage the vessel remained afloat and a very real threat to shipping in the Atlantic or anywhere else. A combined force from No 617 and No 9 Squadron would attack Tirpitz with a combination of Tallboy and 500 lb Johnny Walker mines. The Johnny Walker when dropped near the ship would sink, it would then move forward and sideways a few feet, then float to the surface. If it encountered the ship it would detonate, if not it would sink and repeat the sequence. If no result was gained after a set number of attempts the mine would self destruct. Tirpitz was anchored in Kaas Fjord, out of range of the British bombers even if they used the most Northerly base in the British isles at Lossiemouth. Arrangements were therefore made for them to fly to Russia. They would leave Woodhall Spa and stop at Lossiemouth, with there fuel tanks filled to the brim they would then fly to Yagodnik on the River Dvina, 20 miles from Arcangel. There they would refuel ready for the raid, returning to Yagodnik before the flight home. On September 11th, twenty Lancaster set off accompanied by two B-24 Liberators from No 511 Squadron. The B-24’s carried a spare engine and undercarriage legs along with tinned food, tools, a number of ground crew and the Woodhall Spa Medical Officer Flt Lt Bob Mathews. After refuelling at Lossiemouth they set off, next stop Russia, it would be an average of around 11 hours before Yagodnik would come into view, or rather it didn’t. As they approached their destination they found the weather had closed in, low cloud and mist made seeing the ground difficult, never mind finding a strange airfield. The Russians, not knowing if the circling aircraft were their expected guests or the Germans made no attempt to make the airfield ‘apparent’. Some aircraft spotted landing strips through breaks in the murk and landed, though not necessarily at Yagodnik, but at least they were down. One aircraft ran out of fuel and came down in a swamp, though the crew walked away unharmed. After circling for two hours and flying on fumes, Flg Off Ian Ross saw what appeared to be a wooden plank runway running through a swamp, out of time and fuel he lowered the undercarriage and began what would have to be his only approach......As the runway loomed out of the mist Ross made a perfect 3 point touchdown, throttling back he touched the brakes and the plane started to skid and slide on the greasy planks.With the runway almost twice the width of the Lancasters wingspan Ross managed to control the plane and bring it to a stop just as the end of the runway vanished beneith the nose.Ross surveyed the eerie scene around him, a layer of mist just above the ground, he then joined the rest of the crew outside the plane.They were all stunned to find they had just landed on a runway on stilts, the layer of 'ground' mist was 20ft above the marsh, thankfully the aircraft had stopped 6 ft from plummeting off the end of the runway.Russian troops appeared and took them to join the others for a much needed nights sleep.