Diesel Engines[]
Diesel engines are a pair of internal combustion engines burning diesel fuel that drive the screws.
Diesel engines can only be used when it has a ready supply of air and ability to expel exhaust. This requires either surface use, or for the snorkel to be deployed at periscope depth (requires upgrade). While running, diesel automatically recharges the battery, and drains the Fuel tank.
Speed is restricted to 3 gears forward, 2 gears reverse. Assigning an Engineer allows for 4th gear forward and 3rd reverse, and adding a crew to assist unlocks 5th gear forward, 4th reverse, as well as improved fuel efficiency. A second crew further improves fuel efficiency.
Each crew to a max of 2 assigned to assist adds to fuel use efficiency. This stacks with bonus from Navigation.
| Crew | Effect |
|---|---|
| 0 | Unlocks Forward 4, Reverse 3 |
| 1 | Unlocks Forward 5, Reverse 4, +10% engine efficiency |
| 2 | Unlocks Forward 5, Reverse 4, +30% engine efficiency |
| Gear | Speed (Surfaced) | Speed (Periscope) | Fuel Used | Battery Recharge |
|---|---|---|---|---|
| Forward 1 | 10 kph | 7 kph | 8.7l/km 1l/min | 19.8/km 3/min |
| Forward 2 | 21 kph | 15 kph | 10.9l/km 3l/min | 25.0/km 8/min |
| Forward 3 | 28 kph | 20 kph | 12.5l/km 5l/min | 28.5/km 12/min |
| Forward 4 | 33 kph | 24 kph | 13.8l/km 7/min | 31.7/km 16/min |
| Forward 5 | 38 kph | 27 kph | 13.7l/km 8/min | 34.9/km 20/min |
| Reverse 1 | -12 kph | -9 kph | 5.5l/km -2/min | 12.5/km 4/min |
| Reverse 2 | -17 kph | -12 kph | 6.2l/km -3/min | 14.3/km 6/min |
| Reverse 3 | -20 kph | -14 kph | 6.9l/km -4/min | 15.8/km 8/min |
| Reverse 4 | -23 kph | -16 kph | 6.9l/km -4/min | 17.5/km +10/min |
Notes: Forward 5/Reverse 4 include 10% fuel use efficiency in their fuel used calculations, because you cannot unlock them without adding a crew member.
Fuel is located in Fuel Tank 1 (Crew Quarters) and Fuel Tank 2 (Officer's Room)
| Upgrade | Cost | Effect |
|---|---|---|
| Snorkel | X | Diesel motor may be run while sub is at periscope depth. |
Electric Motors[]
Electric Motors is a pair of battery-powered motors that drive the screws. Electric can be used at any time. While running, electric motors drains the Battery resource.
Speed is restricted to 3 gears forward, 2 gears reverse. Assigning an Engineer allows for 4th gear forward, and adding two crew to assist unlocks 5th gear forward, 3rd reverse.
Each crew to a max of 2 assigned to assist adds to battery use efficiency. This stacks with bonus from Navigation.
| Crew | Effect |
|---|---|
| 0 | Unlocks Forward 4, Reverse 3 |
| 1 | +7% battery use efficiency |
| 2 | Unlocks Forward 5, Reverse 4, +15% battery use efficiency |
| Upgrade | Cost | Effect |
|---|---|---|
| Accumulators I | X | Increased battery capacity by 25% |
| Accumulators II | X | Increased battery capacity by 50% |
| Accumulators III | 18000 | Increased battery capacity by 75% |