Each British drifter on the Dover Barrage in October 1916 carried exactly one rifle. That was the entire defensive armament of the small fishing boats whose job was to tend the anti-submarine nets stretched across the narrowest part of the English Channel. Late on 26 October, two and a half flotillas of German torpedo boats from the Flanders Flotilla - twenty-three large boats, suddenly reinforced from the Baltic - slipped out into the dark and aimed for those nets. The first British vessel to engage them was the destroyer HMS Flirt, whose commander challenged the unknown ships with a signal lamp. They flashed back something that looked similar. Flirt's captain decided he must be looking at friendly destroyers chasing a submarine, and lowered a boat to pick up survivors from drifters that had just been shelled. The Germans then sank Flirt.
The Flanders Flotilla had been quiet for months. Until October 1916 it possessed only three large torpedo boats and a handful of smaller ones - not enough force to risk against the Dover Patrol. Then the German Admiralty transferred the 3rd and 9th Torpedo Boat Flotillas to Flanders, multiplying the available strength almost overnight. The British did not yet know how much had changed. The four divisions of drifters guarding the indicator nets were therefore still armed for routine submarine-spotting, not for a surface action. Six destroyers were available at Dover and elements of Harwich Force lay in The Downs anchorage, but on the night itself the men on the nets had only their rifles, their flares, and the assumption that they would be warned before any serious attack.
The Flanders flotillas split into five groups before sortieing - a deliberate strategy of multi-axis attack designed to confuse the British about what was happening and where. Different groups would hit different sections of the strait simultaneously: the barrage drifters, the shipping lanes in the channel, the transports working between England and France. The German 5th Half-Flotilla was assigned to the barrage and headed straight for the 10th Drifter Division, which was tending the anti-submarine nets near the line of buoys between Folkestone and Cap Gris-Nez. When the firing started, the drifters - armed with that single rifle each - did what they could and were quickly overwhelmed.
HMS Flirt was the escort destroyer for the drifter divisions. Hearing the gunfire, her commander brought her over and challenged the strange ships with a signal. The Germans responded with what looked enough like the correct British signal to confuse him. He concluded that what he was watching had to be allied destroyers engaging a submarine, and that the drifters in trouble had been torpedoed by that submarine. He launched an open boat to pull survivors from the water. Then, with that boat already in the sea, the Germans turned on Flirt herself and sank her. The boat crew survived; most of Flirt's company did not. Their commander's mistake had been one of pattern recognition under stress - exactly the kind of error that the night, the noise, and the chaos of the barrage were engineered by the enemy to produce.
When word reached Admiral Reginald Bacon, commander of the Dover Patrol, he ordered six Tribal-class destroyers - Viking, Mohawk, Tartar, Nubian, Amazon, and Cossack - to engage. Commander Henry Oliphant, in Viking, misinterpreted the orders and deployed his six ships in two loose groups instead of one concentrated formation. Nubian raced ahead alone and was the first to reach the wreck of Flirt. Elsewhere, another German half-flotilla had run down the empty British transport Queen returning from the French coast, boarded her near Goodwin Sands, removed her crew, and sunk her. Bacon dispatched the Dunkirk Division to cut off the German retreat to Flanders, but the torpedo boats slipped away first.
By morning the British had lost one destroyer, a transport, and several drifters. About 45 British seamen were killed, with four wounded and ten taken prisoner. The Germans escaped with only minor damage to one torpedo boat - the cheapest victory the Flanders Flotilla would score against the Dover Patrol in the entire war. The action exposed a system of defenses that depended too heavily on assumptions: that gunfire in the strait meant a U-boat being engaged; that signals received were signals from friends; that a destroyer escort was enough to protect ships armed with a single rifle each. The Dover Barrage would survive and evolve - a deeper minefield, better illumination, faster reaction protocols - but the lessons of October 1916 were paid for in seamen's lives. The same night-time confusion would happen again in February 1918, against an even larger raid, with the same heartbreaking results.
The 1916 raid played out across the entire Dover Barrage line, centered near 51.05°N, 1.60°E - the southern end of Goodwin Sands and the buoy lines running south toward Cap Gris-Nez. The transport Queen was attacked near Goodwin Sands (51.27°N, 1.55°E). From cruise altitude the whole battlefield is visible at once in clear weather: from FL250 the White Cliffs of Dover, the Goodwin Sands shoals (often visible as light patches in the water), the line of channel buoys, and Cap Gris-Nez all sit within a single field of view. Nearby airfields: Manston (EGMH) and Lydd (EGMD) on the English side; Calais-Dunkerque (LFAC) on the French side. The shipping density below today - over 400 ships a day - makes the strait one of the busiest stretches of water on Earth.