Other German aircraft conducted reconnaissance over Moon Sound and were fired on by Russian torpedoboats. Still other aircraft overflew Moon at low altitude and exchanged fire with Russian ground forces. One German aircraft, which appeared over Kuiwast, was shot down by the Russian flyer Safonov and crashed on Moon, with both pilot and observer being killed.
Previously, during the early hours of 16 October, the airships had carried out an attack on Pernau, in the Riga Gulf. The first to attack was L30, and the airship commander, Oberleutnant zur See Vermehren, reported that his bombs had fallen in the town centre. The airships LZ113 and LZ120 (Kapitänleutnant Zaeschmar and Kapitänleutnant von Lossnitzer, respectively) followed and dropped a bomb load of 6,000kg amongst the roads and harbour buildings. Later, during the night, L37 (Kapitänleutnant Paul Gartner) repeated the attack on Pernau with a bomb load of 2,000kg, but this airship returned to Seerappen with the port midship engine gondola burnt out by a serious fire in the air. Airship SL8 (Oberleutnant zur See Ratz), did not reach the target, but was forced to return to Seddin after having trouble with three of her five engines. In Pernau ten people were killed and many houses were destroyed.
The German U-boats had also been active. The minelayer UC60 had the task of laying mines in the Nücko-Worms Channel and then moving to the Finnish Gulf. Early on 12 October the submarine approached Odensholm and spent the day on the bottom before laying her mines successfully in their allocated positions during the evening. Just before midnight she was accidentally rammed by UC58 and her port diving plane was bent, although the mission was continued. Early on 16 October, at around 1015hrs, UC60 came across a Russian transport of approximately 2,000 BRT near a reef by Povskär. The port tube was fired but the torpedo jammed, possibly due to the collision with UC58. The commander, Oberleutnant zur See Fischer, ordered the gun manned and fire to be opened. As the U-boat turned towards the ship, the torpedo slid from its tube and detonated on the bottom, about 15m ahead of the boat. There was some damage to the boat but most importantly about half the batteries were rendered unserviceable. However, UC60 was still able to force the crew of the Russian steamer, Esti, to abandon ship and she was then blown up with explosives. Nevertheless, because UC60, with her damaged batteries, could barely hold headway while submerged, the boat returned prematurely to Libau, returning via Dagerort and over points Gamma, Beta and Alpha.
During 16 October the Russians received further reinforcements in the form of the torpedoboat-destroyers Emir Bucharski, Straschnyi and the armoured cruiser Diana. During the early morning, at about 0520hrs, the U-boat UC58 sighted the cruiser in the southern part of the buoyed channel between the light houses of Cape Tachkona and Odensholm. The U-boat commander, Kapitänleutnant Vesper, thought the cruiser was Bogatyr, but it was in reality Diana, travelling behind the two destroyers as an anti-submarine screen, along with five minesweepers. UC58 attacked with her two torpedoes through the calm sea, and one torpedo was observed by the Russians to pass under the stern. Back on the German submarine a detonation was heard, which they took to be a hit. In reality the torpedo struck the bottom and exploded. The two destroyers counterattacked and unsuccessfully dropped depth-charges on the U-boat. For the following morning Diana was ordered to occupy a position guarding the northern entrance of the Moon Sound.
The previous day the minelayers Zeya and Bureya had arrived from Helsingfors and took on mines in Rogekul. From there they went to Kuiwast roadstead to join Pripyat that evening. They assembled with the minelayer Volga. Despite the resolution of the Russian torpedoboat commanders that the planned foray into the Kassar Wiek was impossible, the boats of the IV, V and VI Division Torpedoboat-Destroyers, a total of ten boats, nevertheless assembled near Cape Seanin in the evening. The Novik type destroyers of the I, II and III Divisions and the gunboat Chrabry supported them. As long-range support, the battleships Slava and Graschdanin situated themselves near Schildau and Admiral Makarov went to Severy Water, in the northern Moon Sound.
Therefore, because there were no spare ships available, the planned production of a new mine barrier in the Riga Gulf had to be cancelled. Admiral Bakhirev remained in complete ignorance about the position of the Germans in the Irben Straits. Nevertheless, during the night a patrol was advanced to Larina Bank, south of Moon Sound. It consisted of the torpedoboats Deyatel’nyi and Del’nyi. They were to advance into the Riga Gulf at day break.
During the evening Vice Admiral Bakhirev received notification from Rear Admiral Razvozov that the German landing on Moon had been postponed, and therefore he gave an order by wireless to the torpedoboat division chief to cancel the night operation. Admiral Stark then set the coal-fired torpedoboats along the edge of Moon Sound.
The weather on 16 October was particularly favourable for the continuance of minesweeping in the Irben Straits. Although late autumn usually produced bad weather, for the third consecutive day the weather was fine. There was a slight south-southwesterly wind, a light sea running and good visibility. Early in the morning, at around 0700hrs, the III Minesweeper Division, followed by the 3rd S-Half Flotilla and IV Minesweeper Division, advanced, sweeping a 400 metre-broad mine-free channel. Just north of barrier gap 4, more mines were found, forcing Kontreadmiral Hopman’s cruisers, Kolberg, Strassburg and Augsburg, and Vizeadmiral Behncke’s two battleships, König and Kronprinz, which were travelling in the wake of the minesweepers, to stop at about 1100hrs. During this pause the torpedoboat A62 sighted a barge to the north, which immediately showed the white flag. The barge, which carried 300 men of the Sworbe garrison, was taken in tow by Kapitänleutnant Doflein’s minesweeper. During the previous day, as they were being evacuated from Sworbe, the barge had broken free from its tug and during the night had drifted into the Russian mined area. Fortunately they were now rescued and the II Minesweeper Flotilla chief received orders to tow them to Arensburg.
When the advance from barrier gap 4 towards Arensburg resumed, the German units found themselves in the following order: ahead was the III Minesweeper Division, then the 3rd Minesweeper Half Flotilla, both with sweeper gear set; 8th MSHF without gear, followed by the BdAdO’s flagship SMS Kolberg; 3rd S-Half Flotilla and IV Minesweeper Division, both with sweeper gear set; two sperrbrecher vessels, followed by König and Kronprinz; then Augsburg and finally the support vessel group or ‘train’. The buoy layers Wilhelms and Mellum marked the swept channel with buoys and the entire unit traversed the Russian mined area without incident, surely a credit to the tenacious minesweeper units.
During the journey across the Irben Straits, at around 1130hrs, König received a new order from Vizeadmiral Schmidt’s staff by wireless: ‘Attack the Russian forces in the Moon Sound and Riga Gulf with all possible means’. It was an important expansion of Vice Admiral Behncke’s brief. Hitherto the primary task for the second phase of the operation had been to advance to Arensburg , make it a secure anchorage for the II Section of the transport fleet and to direct their unloading. Now the principal task was the accelerated attack on Moon Sound and the securing of Arensburg assumed a secondary importance. Vizeadmiral Behncke determined to push forward to the southern entrance to Moon Sound with his strongest forces that same day. He intended to anchor during the night and then to break into the southern Moon Sound on the following morning to attack any Russian forces he might find there. He therefore determined to use his two battleships, the small cruisers Kolberg and Strassburg, the VIII Torpedoboat Flotilla, the 20th Torpedoboat Half Flotilla and four trawlers of Coastal Protection Half Flotilla East. The cruiser Augsburg would supervise the occupation and unloading at Arensburg. The minesweepers would be split, the IV Minesweeper Division and 3rd S-Half Flotilla, whose motorboats were without a tender, would work off Arensburg, whilst 3rd and 8th MSHF and III Minesweeper Division and their tender Indianola would accompany Vizeadmiral Behncke.