UBOOTSIM

November 1941. The Strait of Gibraltar. You command a Type VIIC U-boat: 67 metres of steel, four bow tubes and one at the stern. On the horizon, smoke from a convoy: five freighters and a tanker, guarded by a destroyer and two corvettes. Your mission: sink as much tonnage as you can and make it home alive.

UBOOTSIM is a World War II submarine simulator made to be enjoyed at your own pace. Every attack is a small game of chess between you, the convoy and its escorts.

HUNT - Attack periscope and bridge binoculars, with 1.5× to 6× zoom, a bearing scale and an automatic 360° sweep. - A living daylight sea: swell, whitecaps, clouds, sun glitter and funnel smoke that gives the convoy away long before its hulls. - Hydrophone to hear propellers while submerged: slow, heavy merchants and fast escorts. An audible alarm sounds for every new contact. - Tactical chart of the Strait with its coastline, grid, bearing ring, contacts and wakes. Tap a point and the helm and periscope turn towards it.

STRIKE - Lock the target, take bearing and range marks and let the Torpedo Data Computer (TDC) find the solution. When the button turns green: fire! - Fine-tune the target's range, course and speed by hand, or switch on the automatic TDC for a more relaxed game. - Spreads of 1, 2 or 4 torpedoes, a stern tube and real-time reloading, one tube at a time. - Follow every torpedo with its wake, its countdown and a tracking window that zooms in for the last seconds. And, just as in 1941, some pistols fail. - On the surface, the 8.8 cm deck gun: tap the ship, wait for the green ring and fire. The crew corrects their aim with every hit.

SURVIVE - After the first hit the convoy raises the alarm, turns and speeds up, and the escorts come after you with ASDIC and depth charges. - Go below the thermal layer, run silent, change course after every pass and keep an eye on your hull and battery. - Underwater side view: your U-boat angled as it dives, enemy hulls above you with the metres beneath their keels, and depth charges falling and bursting all around. - While you run on the surface a patrol aircraft may appear. If it spots you, it attacks and radios the destroyer. Dive in time… or shoot it down with the deck gun.

A SUBMARINE YOU CAN FEEL - Diving depends on your speed: at full ahead the boat dips its bow and goes down at an angle; stopped, it barely sinks. - Alarm bell and the call of "Dive! Dive!" as you submerge, and "Surface! Surface!" as you come up. - Diesels rumbling on the surface and electric motors humming underwater, higher-pitched the faster you go. - The blast of compressed air at launch, the whistle of running torpedoes, explosions, ASDIC pings against the hull and depth charges that grow louder the closer they burst.

SHIPS WITH CHARACTER - Freighters from different shipping lines, with coloured funnels, lifeboats and cargo derricks. - A long, low tanker: the big prize. - A fast, camouflaged destroyer with four guns, and two corvettes that never stop circling the convoy. - The more you zoom, the more you see: windows, flags, pennant numbers on the bow and fires when you hit them.

FOR EVERY COMMANDER - Time compression from 1× to 32×, dropping back to 1× automatically at any danger. - "Show all ships" mode to learn the game. - Built-in quick guide in English and Spanish. - Scalable display: stretched to fill the window or proportional, as you prefer. - For iPhone, iPad and Mac, with a native Mac version and keyboard controls.

Ship names are fictional. UBOOTSIM is a game: it simplifies reality to make it playable, while staying true to how war at sea was fought in 1941.

Good hunting, Commander!

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