Towards 1128hrs a false submarine alarm was given on the German battleships when a boat hook was mistaken for a periscope. After the attack by C27 the previous day, the Germans were acutely aware of the danger from submarines and, therefore, at noon Gruppe Behncke weighed anchor and proceeded up and down the eastern swept channel at low speed, under the protection of an anti-submarine screen. At around 1208hrs another submarine alarm was given, to port ahead, bearing 350 degrees. This time the alarm was real for it was C26 (Lieutenant Downie), which was manoeuvring to attack the German battlegroup. At the beginning of Operation Albion, C26 had been in Hango, but in the meantime had proceeded south and now found herself south of the Moon Sound in a favourable position to carry out a torpedo attack. Unfortunately, Lieutenant Downie was hampered by the shallow water depth and before arriving in a firing position found himself hard aground. C26 was unable to come free by going astern and therefore had to blow her ballast tanks to release herself. In doing so the boat broke surface with her conning tower and was seen by the Germans, so that the torpedoboats immediately took up the hunt for her. The torpedoboats opened fire with their guns and depth charges and continued the hunt for over two hours, at one stage forcing C26 into a net where she damaged her propeller. After darkness, Lieutenant Downie was able to surface and found that his hydroplanes had been damaged and jammed, rendering his boat unseaworthy, so he took his crippled submarine to Pernau, hoping to be able to effect repairs there.
In the meantime, the Gruppe Behncke had continued to press forward, although the way was not easy. The south-southeast wind and rising sea made the work of the advancing minesweepers difficult and they frequently slipped their gear on the rocky bottom. The motorboats of the III Minesweeper Division were forced to cease their activity because of the deteriorating weather. The 3rd Minesweeper Half Flotilla, led by A62, continued towards Kuiwast Roads. However, they soon ran into a heavy net barrier, supported by iron barrels, running in a semicircular arc between the islands of Wirelaid and Werder, directly across the southern entrance to the Moon Sound. The minesweepers were unable to penetrate this barrier, so, towards 1540hrs, Vizeadmiral Behncke ordered the work to be broken off and at about 1700hrs the battleships, screened by torpedoboats, anchored southwest of the trapezoidal minefield. At 1730hrs, A62 and the 3rd MSHF anchored with them.
Towards 0900hrs, when Vizeadmiral Behncke had resumed his advance towards the southern Moon Sound, Kontreadmiral Hopman had, likewise, again begun to press forward with his small cruisers into the Kleinen Sound. The minesweepers of the 8 MSHF were nevertheless encountering difficulties because of the error in communicating the locations of the Russian minefields learned from Grom’s captured charts. Having clipped the southwest corner of the trapezoidal minefield, the sweepers’ progress was slow and it was not until towards noon that the cruisers, minesweepers and sperrbrecher ships arrived in the northwest of the Kleinen Sound at the 10 metre line. The minesweepers then went ahead to take soundings but T53 and A35 briefly went aground. Kolberg briefly took the Woi battery under fire for ten minutes from 1335hrs, but the Russian battery did not reply, so that Kontreadmiral Hopman had to ask the I FdT what the situation was.
Towards 1425hrs Kolberg and Strassburg anchored in the southern entrance of the Kleinen Sound. Then Kontreadmiral Hopman’s flag lieutenant, Oberleutnant zur See Kelm, suggested that the two batteries on Woi could be captured by a landing party and offered to lead the group. A landing party of forty men and two machine guns was quickly assembled and made ready and at 1545hrs they were landed under the cover of two M-boats that had moved close inshore. At 1730hrs a white star shell was observed, the signal from the landing party that the battery had successfully been taken, though the guns had been rendered unserviceable. This small band were the first Germans to arrive on Moon.
The Landing Corps on Dago had a much more difficult time of it. At 0925hrs SMS Kaiser carried out a preparatory bombardment of the bridgehead area at Serro, which continued for thirty-five minutes. Section Ahlefeld was landed immediately afterwards and during the day patrols penetrated far inland, but nevertheless suffered some losses. At midday the transports Oswald, Sangara and Borderland, together with horse transports and barges, arrived off Cape Toffri, but the anchorage was not yet ready to accommodate them. Similarly, a cyclist battalion was delayed and only arrived at Pamerort around midday, so that all intended support for Section Ahlefeld was delayed and the Landing Corps was again forced to retreat to the bridgehead towards evening. Because of the difficulty in transporting the wounded it was decided to occupy the bridgehead overnight, although trawlers stood by, ready to evacuate the German troops should the Russians press home an attack. Although the fighting had been lively during the day, the night passed quietly for the Germans.
Nevertheless, although Section Ahlefeld was being sorely tested the Russians themselves were having problems. The force that had attacked the Germans had been a unit of 35 Jagers, whereas the 427th Grenadier Regiment had refused to go on the offensive and had retreated to Kertel, and some went to Helterma. Likewise, there was unrest amongst the crews of the gun batteries. The crew of Battery No 38 held a general assembly and determined to request support from the sea. If this was not forthcoming then they proposed to retire to the rear. They asked the crews of batteries No 39 and No 47 to join them, but these crews rejected their proposal. Nevertheless the commander of Battery No 47 was ordered to immediately render his guns unusable without making detonations, fire or noise, and the crew then retreated.
For the German forces in the Kassar Wiek, 17 October was a relatively quiet day. During the morning the craft of the II Torpedoboat Flotilla and the 13th Torpedoboat Half Flotilla were resupplied with 1,830 rounds of 10.5cm ammunition from V45, V44 and T139, whilst at the same time a continuous watch was kept on the entrance to Moon Sound. Five minesweepers of the II Minesweeper Division searched for mines in the Kassar Wiek, the ‘Pripyat’ barrier, but a shortage of fuel forced them to return to their tender in the Tagga Bay at around noon.
When the thunder of cannon was heard during the morning, the I FdT, Kommodore Heinrich, pushed forwards towards Moon Sound with V100 to investigate. At about 1154hrs the Russian forces in the Moon Sound were observed to begin lively movements, mostly in a northerly direction. At about 1155hrs a huge smoke cloud from an explosion was observed on a battleship east of Kumora, which was in fact the detonation of Slava’s aft magazine. Towards 1500hrs, Kommodore Heinrich took V100 forward into the channel that led to Moon Sound but he immediately came under the well-directed fire of Chrabry and the torpedoboat-destroyer Konstantin.
When the commander of the Sea Forces of the Riga Gulf had signalled ‘Retreat’, Kontre Admiral Stark signalled ‘Rendezvous at Worms’, and moved near to Kumora Reef with Novik. He ordered the minelayers Bureya and Pripyat to prepare to lay mine fields. Bureya, under Leitenant Semenov, was ordered to lay a mine barrier north of Seanin buoy, between there and the shore, in the 16 foot-deep channel between the Kassar Wiek and the Moon Sound. Leitenant S I Medvedev and Pripyat were ordered to produce a mine barrier near Schildau Island in the Moon Sound. The III Division Torpedoboat-Destroyers was to screen the operation. Kontre Admiral Stark considered it too risky for these shallow-draft minelayers to operate on Kuiwast Roads.