After leaving Wilhelmshaven, Zhang Hainuo carefully reviewed the cards he held once again: a UBIII-class submarine that had undergone major repairs, 25 crew members with varying levels of experience, enough fuel for the submarine to travel at least 6000 nautical miles under normal conditions, 10 450mm torpedoes, 85 rounds for the 100mm deck gun, two crates of 8mm machine gun ammunition, and food supplies and fresh water to sustain all crew members at sea for seven to eight weeks.
Compared to Hessen, Zhang Hainuo's dilemma was not only leading a group of temporarily inexperienced and relatively inexperienced crew members but also navigating the more complex and volatile waters of the Atlantic Ocean, where British and American escort ships were stronger compared to those in the Mediterranean, and his command experience was far inferior to Hessen's. The situation of U171 was indeed much more severe than that of U21.
Before setting sail, Zhang Hainuo had a special conversation with Senior Chief Engineer Sergeil Shakhed, a shy young man who was not originally the "original" senior chief engineer of U171. He had previously served as the assistant senior chief engineer on a UD-class submarine with a displacement of 1100 tons and had only recently been transferred along with other new crew members. In the past few days, Sergeil had conducted a comprehensive inspection of the power system on board and learned about the details of U171's major repairs from another veteran engineer: one diesel engine, two electric motors, and two-thirds of the oil pipes had been replaced, and the damaged hull from previous battles had been fully repaired.
In theory, the submarine's sailing and combat capabilities had been basically restored, but Zhang Hainuo knew that, like a car after major repairs, the submarine needed a period of running-in after repairs to reach its optimal state.
Now, the only thing that made Zhang Hainuo happy was that before entering the heart of the Atlantic, U171 would sail in company with two other submarines—U89 and U145. U89 was the UD-class submarine Sergeil had mentioned, the largest and longest-range submarine in Germany at present, but there weren't many of them. U145 was also a UBIII-class, newer than his own. The captains of these two submarines were both veterans, with their records exceeding 40,000 tons, while Zhang Hainuo's record book hadn't even been opened yet!
On the day they left port, Zhang Hainuo commanded the crew to conduct the first full-speed sea trial of U171 after the major repairs. The situation was better than he had imagined. The newly commissioned UBIII-class submarine could reach a maximum surface speed of 16.5 knots, and this time, U171 achieved 16.1 knots under good sea conditions.
However, they encountered some trouble during the subsequent diving sea trial. Just as the submarine submerged to a depth of 15 meters, leaks appeared in the ventilation pipes on board, causing the new hands to panic. Fortunately, several experienced crew members promptly rectified the fault. Upon Sergeil's suggestion, the submarine resurfaced and underwent thorough maintenance on the ventilation pipes.
During the three-plus hours of maintenance on the ventilation pipes, Zhang Hainuo, standing on the submarine's command tower, felt a tension he hadn't experienced on U21—British cruisers and destroyers could appear at any time in the waters near Germany and Denmark in the southeastern North Sea, and the British naval officers and sailors aboard were the most alert and experienced among all the fleets. Despite the presence of U89 and U145, Zhang Hainuo dared not be complacent.
After enduring until evening, U171 once again submerged, this time safely diving to a depth of 35 meters, which was considered the safe depth by submarine captains. Zhang Hainuo finally breathed a sigh of relief.
As the submarine had just left its homeport, the dinner that evening was very sumptuous, with fresh meat, vegetables, and milk readily available. However, Zhang Hainuo felt that the atmosphere here was somewhat lacking compared to U21. It took him a long time to realize that the crew members, although engaged in lively conversations, were not as carefree in their jokes as Hessen and his crew.
"Let's play riddles, everyone! I'll start, and whoever guesses it correctly gets a reward! If you guess wrong, you'll drink a big glass of milk. Raise your hands to answer, understood?"
"Understood!" The crew members began to rub their hands, especially the young men working in the engine room—where the noise was the loudest and the hardest working position on board. Although substituting for an hour's duty wasn't a big prize, it was still quite a bargain for them.
"There's something long and round, with fur at one end, and every one of us here has it! Its purpose is to poke around, but some people poke several times a day, while others poke once every few days, and some people have never poked! Guess what it is?"
Seeing no one answering, Edward raised his right hand.
"Alright, you answer!"
"It's... a toothbrush!"
"Correct!" Zhang Hainuo clapped his hands and then smiled at the other crew members. "Those who guessed wrong, drink a glass of milk voluntarily!"
At this moment, the expressions of the crew members varied. Some drank the milk obediently, while others pretended to be indifferent but couldn't help glancing around embarrassedly.
"Okay, Edward, I'll take your duty for an hour tonight! Now, I'll ask another question. Whoever guesses correctly, I'll take their duty for an hour, and if you guess wrong... you have to sing a song! Do you agree?"
"Agree!" Everyone agreed in unison.
"Great! A healthy couple gave birth to a child without eyes. Why?"
This kind of brain teaser was Zhang Hainuo's favorite since childhood, and he could come up with a bunch of similar questions off the cuff.
The crew members looked at each other, and a young crew member who seemed quite young raised his hand to answer.
"That couple was cursed by the devil?"
"No, the reason isn't here!" Zhang Hainuo thought carefully. "Your name is Pell, Pell Domaschek, a first-class sergeant in the torpedo compartment, right?"
The young crew member nodded.
"How about singing a song?" Zhang Hainuo said with a tone of negotiation.
The young crew member hesitated for a moment. "Okay, I'll sing a folk song from my hometown! Ahem, the clouds in the valley..."
The singing wasn't professional, and the melody was quite simple, but after the young man finished singing, Zhang Hainuo led the applause warmly.
"Alright, does anyone else want to try answering? Anyone?"
This time, there were various answers, but none of them were correct. After all, people's thinking in this era was relatively straightforward. But Zhang Hainuo was quite satisfied. He not only listened to many songs, which enhanced his understanding of his crew members, but also brought himself closer to them.
"Let me announce the answer! The answer is... a rooster and a hen laid an egg, and the egg doesn't have eyes!"
As the answer was revealed, the crew members unanimously exclaimed "Oh!" realizing that the answer was so simple.
Next, Zhang Hainuo had the crew members take turns asking questions, with corresponding rewards and punishments for correct and incorrect answers. It was evident that every crew member was enjoying themselves. At that moment, he seemed to become the class's cultural officer and also resembled a kindergarten teacher, but he didn't mind. The key was to relieve the tension of the crew members, especially the newcomers, and adjust their mindset to better engage them in the upcoming battles.
When would the first battle begin? Zhang Hainuo wasn't sure, perhaps in a week, perhaps tomorrow, or perhaps tonight. Zhang Hainuo smiled, but he knew that the brutal battles and the hunt-and-counter-hunt of determination and courage would come sooner or later, and victory often belonged to those who were clever, brave, and prepared.