Two hours had passed since the tumult of the battle had subsided, and Zhang Hainuo, leaning against the submarine's bulkhead, felt a sense of physical exhaustion, with his close-fitting clothes seemingly dampened by sweat.
Why did it have to be like this? Was it his fault?
These questions kept repeating in Zhang Hainuo's mind. Hessen could sink a whole bunch of enemy ships effortlessly, while he nearly lost his life on his first attempt!
Edwin walked over from the direction of the torpedo room without speaking. Instead, he sat down beside Zhang Hainuo, their shoulders touching against the hard bulkhead.
"Do you think I'm a competent submarine commander?" Zhang Hainuo asked, feeling somewhat disheartened.
"Of course, you saved this submarine and all our lives in the most critical moment!" Edwin affirmed.
"But it was my arrogance that put you all in this crisis! If I wasn't so overconfident, maybe we could have avoided the British attacks like they did!" Zhang Hainuo referred to the commanders of U89 and U145. From the previous circumstances, their decision to evade was entirely reasonable, as submarines were not technically superior in direct confrontation with enemy destroyers, especially when outnumbered!
Edwin didn't directly assess Zhang Hainuo's self-blame but instead asked him, "Hainuo, do you think the Battle of Dogger Bank was a mistake?"
"The Battle of Dogger Bank?" Zhang Hainuo raised his head. It was a medium-scale naval battle that occurred before the Battle of Jutland, fought between the British cruiser fleet commanded by Beatty and the German cruiser fleet under Hipper. It took place in the Heligoland Bight, not far from the German coast. The battle was somewhat convoluted, and though the British fleet emerged victorious, the Germans did not suffer a complete defeat, managing to retain most of their participating ships despite being outnumbered.
"Perhaps you've forgotten, but our instructors told us that sometimes battles happen beyond our control, but we can change the outcome through our efforts! What you asked me to do earlier might have seemed baffling, but I believe in you, Hainuo! So I did it, and it worked!" Edwin's calm smile reassured him.
For a while, Zhang Hainuo nodded, looking at Edwin. "Yes! We succeeded! We weren't sunk by those British destroyers and their powerful weapons. That's quite an achievement!"
A serene smile spread across Edwin's face.
Glancing at the others in the command room – First Officer Simon, Communications Officer Strom, Gunner Hacker, Operations Officer Cook, and others – all now wore relaxed expressions.
This sight lifted the heavy burden from Zhang Hainuo's heart. He stood up and exclaimed, "Alright, everyone! The toughest moment has passed. Now let's check the submarine for damages and then surface!"
Despite the one-sided nature of the battle, Zhang Hainuo felt fortunate that none of the crew suffered serious injuries, and there were no casualties. If all went well, the damage to the submarine itself should also be minimal.
Shortly after, reports came from all compartments confirming that everything was normal, even the previously leaking engine room had rectified mechanical faults, boosting the morale of the crew.
"Surface to periscope depth!" Zhang Hainuo's mood lightened considerably.
Upon raising the periscope, Zhang Hainuo found no trace of enemy ships on the surface. Nevertheless, he remained cautious, ordering the submarine to surface only partially, with just the command tower visible above the waterline, while most of the hull remained submerged. He then surveyed the surroundings through the periscope, ensuring that the British airship had indeed departed, before finally ordering the submarine to surface completely.
The two diesel engines were quickly restarted, their sound even more melodious to Zhang Hainuo's ears than heavenly music. Crew members began climbing out onto the deck, breathing in the fresh air of the surface. Some lay sprawled on the deck, basking in the sunlight.
At this moment, everyone was exclaiming, "How good it is to be alive!"
Indeed, just the thought of narrowly escaping death made Zhang Hainuo feel a sense of relief. Yet, his mind was still preoccupied with the questions that had plagued him during the day. Summarizing them, there were mainly two: how did the British manage to precisely track U171 underwater, and what kind of weapon was that which caused loud noise but little damage.
Historically, the British invented passive sonar in 1906, but as far as Zhang Hainuo knew, it was initially used to detect underwater icebergs rather than submarines. At the beginning of World War I, most British naval vessels were not equipped with devices specifically designed to detect submarines. Such equipment, like hydrophones and rudimentary sonars, were developed and installed only as the war progressed. As for the state of British sonar technology by 1917, Zhang Hainuo had no knowledge.