After the interrogation was over, Qian Tiandun asked the briefing of the results to be sent back to the Yong'an Port Headquarters by radio. Although there is not much information obtained, it is still possible to deduce a part of the military situation of the South Vietnamese side from the limited information. For example, from the scale of military ration delivery in South Vietnam, it can be inferred that the strength of the South Vietnamese army in the area north of the Truong River is about 30,000 to 40,000, far from the 70,000 or 80,000 that the North Vietnamese side believes, and there is no overwhelming superiority in troops. However, judging from the other side's continuous replenishment of troops to the theater, there may still be tens of thousands of troops in the area south of the Zhengjiang River, but they have not yet been put into the battlefield at one time.

Qian Tien Dun and others speculated that the South Vietnamese Army did not put all its troops into the theater of operations, and still adopted the tactic of adding fuel even though it had gained an advantage in the battle situation, and the fundamental reason for this was probably because of the lack of supply capacity, which was a last resort.

According to the prisoners' confessions, Donghai, located 50 miles south of the Zhengjiang River, is currently the rear base camp of the Northern Expedition of South Vietnam, and grain, grass, soldiers, and materials are all transported to the north after being concentrated in Donghai. However, starting from Dong Hai, it is necessary to cross Hengshan and Zhengjiang and then reach the forward theater, and this supply line that is more than 100 miles long has mountains, rivers and swamps, and the transportation conditions are very bad. If more troops were put into the front line, the South Vietnamese army could collapse due to supply problems.

"This is the disadvantage of not having the ability to transport by sea!" Sun Changmi pointed out the biggest problem of the South Vietnamese army: "If they could have a fleet like ours, then the North Vietnamese defense line would have been broken long ago." ”

This is probably the reason why the civil war in Annam lasted for decades, and in the end it had to maintain the dividing line of the Hengshan River. Qian Tiandun stared at the map and added: "You see, whether it is from north to south or from south to north, the side that crosses this dividing line will face the problem of supply, and if this problem cannot be solved, the battle situation will not be able to continue." ”

Is it possible to think that even if the North Vietnamese mountain defense line collapsed, the South Vietnamese army would have difficulty maintaining an excessively long supply line, and would probably eventually stop the offensive of the Northern Expedition on its own. Tom Wang offered a new perspective. Prior to this, the general view of the Military Police Department was that once the North Vietnamese defense line was broken, the terrain of the North Horse Pingchuan River was likely to be pushed all the way by the South Vietnamese. But judging from the reconnaissance results, it seems that it is not so simple to push flat to Thang Long Mansion.

"It's hard to say, if the South Vietnamese army can find a way to collect food on the spot after the battle, then the North Vietnamese may really be unable to parry. However, if the North Vietnamese cleared the field in advance and did not give the opponent the opportunity to raise grain and grass on the spot, then the South Vietnamese army would indeed be delayed by the supply problem. Qian Tiandun muttered: "But we can't take this risk, no matter whether the South Vietnamese army has the ability to directly overthrow the North Vietnamese regime, as long as there is a rout on the North Vietnamese side, the result will definitely not be in our interests, so this battle must still be fought." ”

"I think we can look at the situation from a different perspective. Xie Chun also joined the discussion: "Whether it is South Vietnam or North Vietnam, their shipping capacity is very poor, in fact, we only need to control the sea power, and we can basically control the trend of their civil war." ”

"Speaking of which, you just want to expand the scale of the Black Earth Port Shipyard, right?" Sun Changmi immediately pointed out Xie Chun's true purpose: "The Executive Committee of this matter must agree in principle, but I am afraid that it will not give much practical help to the Black Earth Port, because the shipyard of Shengli Port also has a big expansion plan in the first half of the year, and the Executive Committee can only give priority to the needs of the base camp." ”

"Then what should we do in Heitu Harbor? We can't just stop at the level of building a few fishing boats, right?" Xie Chun obviously couldn't accept this news.

"My personal construction is ......," Sun Changmi muttered, "You can think of a way from Lianzhou Mansion." In the coastal cities of Yong'an, Qinzhou, and Lianzhou, there must be many shipwrights who can be introduced in a targeted manner. ”

Xie Chun frowned, and did not continue to argue with Sun Changmi on this issue. Since the Black Earth Port has the ability to make blood, the support of the base camp for the Black Earth Port is not as great as before, but the autonomy given to the Black Earth Port is indeed very large, not only can it independently introduce immigrants, but also has the right to trade with North Vietnam and even the Liangguang region on its own. Even the military power, which is most valued by the Executive Committee and the Military Police Department, has opened a back door to the port of Heitu, allowing the local militia to organize its own militia for training. The main purpose of the base camp in giving these autonomy to the Black Soil Port is to hope that the Black Earth Port can be self-reliant and solve some basic development needs on its own.

"The shipbuilding matter, whether you are in a hurry or not, let's think about the direction of tomorrow's reconnaissance. Tom Wang said a fair word and brought the topic back to business: "According to our reconnaissance today, there are at least tens of thousands of South Vietnamese troops between the south of the Zhengjiang River and Dong Hai. I think that if we continue south, we may be discovered by the South Vietnamese army. ”

Qian Tiandun pointed to the map and said: "Even if we want to start a sabotage war, we will take the battle for the river as the main battlefield, and the purpose of the operation is to destroy the opponent's supply line." In my opinion, we should take the area north of the Zhengjiang River as the main object of reconnaissance, after all, if we want to open up a second battlefield, the distance of force projection through Guò sea should not be too long. ”

Early the next morning, the fleet pulled anchor and sailed slowly north along the coastline. From the shore where we had camped last night to the zone of engagement, it was only about ten nautical miles.

In order to conceal their tracks, after a certain voyage, the fleet turned to the open sea, maintaining a distance of four or five nautical miles from the coastline to avoid detection by the South Vietnamese army on land.

At a distance of more than ten miles from the South Vietnamese front-line barracks marked by the advance team, observers on both ships noticed through their binoculars that small barracks were beginning to appear on the coast. These camps stretch all the way north, and the further north you go, the denser they become.

"Pay attention to the mountain pass to the northwest, where the North Vietnamese army was breached at the beginning of the month. Qian Tiandun held a telescope in one hand and a walkie-talkie in the other, and communicated with Wang Tom and others on the "Feisu" while observing.

The mountain pass that Qian Tiandun mentioned was located about six or seven miles south of the mountain line line, almost parallel to the mountain line of another mountain range, extending from the inland to the east to the sea. It's just that there is a gap more than a mile wide in the middle of this mountain range, which is far less precipitous than the current defense line. It is no wonder that the North Vietnamese army did not hold out for even ten days before the defense line was breached, and now a large number of South Vietnamese troops are stationed on the north and south sides of this mountain pass.

"This level is only a few hundred meters from the sea, so I think I can use my brain here. Tom replied on the walkie-talkie.

"I'm afraid it's hard. Qian Tiandun was not very optimistic about this: "Our militia plus the trained troops of North Vietnam have more than 1,000 actual combatants. It is too difficult for more than 1,000 people to maintain a front seven or eight hundred meters wide. You know, we don't have the opportunity to dig trenches and repair fortifications in that place, and as soon as we land, we will face an attack of 30,000 or 40,000 troops from the north and south, which is too risky. ”

"Let's go ahead and see, I remember there's another candidate to the north. After hearing this, Tom Wang also felt that Qian Tiandun was reasonable, so he did not insist on his own opinion.

The fleet continued northward, and soon came across the candidate site that Tom King had mentioned. This is a triangular sandbar surrounded by two hills at an altitude of more than 100 meters above sea level, and the only opening of the sandbar to the inland is in the west, and to the west of this pass, which is about 200 meters wide, is where the main camp of the South Vietnamese Army is located. The distance from the sea to this narrow pass is about five or six hundred meters, and there are not too many obstacles on the ground, so if you land from here, it is indeed easy to control the western pass. Geographically, this place is similar to the port of Yong'an built by the Military Police Department in the rear, both of which are seaside beaches surrounded by hills and mountains, and both have natural passes for fortifications.

"This place is good!" Qian Tiandun exclaimed after seeing the actual terrain here from a distance from the boat: "With such a terrain, the South Vietnamese army can only feed bullets with human lives!"

"If you start fighting the South Vietnamese army in this place, I'm afraid they won't be hiding the musketeers anymore. Tom Wang also agrees with Qian Tiandun's point of view.

In the current mountain attack, the South Vietnamese army has never put its precious firearms troops into the battlefield, because the offensive and defensive battles in the mountain positions are indeed not suitable for musketeers to exert their combat effectiveness. But if the battlefield is flat, there is no reason why the South Vietnamese army should not sacrifice the sharpest weapons in their hands.

Two or three miles further north from here is the mountain defense line built by the North Vietnamese army. After inspecting this area from the sea, the reconnaissance team did not rush back to Yong'an Port, but chose to sail eastward and went around to the back of the Duyo Island in the open sea and docked.

For this kind of small-scale infiltration and reconnaissance, it is not appropriate to use Qian Tiandun's special operations company. However, Qian Tiandun did not plan to be idle, but proposed to act with Wang Tom and others. Although there were also opposing voices, believing that the two senior commanders should not go deep into the dangerous ground at the same time, Yan Chujie, who was sitting in the rear, still made a decision and agreed to their application for action.

It was only after night that the "Speed" turned out from behind the island and slowly sailed towards the shore. Nearly two hours later, the "Feisu" completed this short voyage and approached the target location.

The South Vietnamese army did not choose to station troops on this sandbar near the sea, and after the "Feisu" approached the shore, it recklessly turned on its searchlight equipment to confirm the coastal terrain, dropped anchor near the shore, and then several people boarded the rubber inflatable boat and rowed to the shore with oars.

Morgan lowered his voice and said, "I never thought that one day I would be smuggled into Vietnam in the middle of the night in a rubber boat. ”

"You're not the only one who thinks this way!" Qian Tiandun also replied with a suppressed voice.

Under the moonlight, it is difficult for the naked eye to see the black rubber boat that rises and falls with the waves. After arriving at the beach, Qian Tiandun and Roger, who were sitting in the front, jumped into the water, grabbed the handle of the bow of the boat with their hands, and dragged the rubber boat to the beach and ran aground. Several other people also went down to the shore at this time, and together they carried the rubber boat to the land so as not to be swept away by the waves.

"Bring night vision devices, check your weapons, and walk along the foot of the hill at five-meter intervals, taking cover in front and back. "Tom Wang gave the order to act as the commander.

Soon the heavily armed detachment was heading inland to the west along the hill that surrounded the sandbar. They first had to confirm the location of the South Vietnamese military camp and the location suitable for their defensive positions, and then when they returned, they would find the shortest landing route from the sea to the predetermined position.

The South Vietnamese battalion was clearly worse defended than the squad had anticipated, and there were no early warning posts outside the camp, perhaps they also thought that it was impossible for the North Vietnamese to cross the sea and launch a sneak attack from their flanks and rear.

The detachment confirmed the location of the South Vietnamese military camp and then reconnoitred the area of the intended position, and the whole process did not alarm the South Vietnamese army at all. After completing the scheduled mission, the team carried out all the reconnaissance of the landing area in a hurry, and the unhurried statement to the command was the real reason for the delay in the operation due to poor visibility at night.

After completing all the reconnaissance work, the team once again boarded the "Feisu" in a rubber boat, and then notified the "Discovery" waiting in the open sea. The two ships did not delay here any longer, and after the rendezvous, they sailed north towards Yong'an Harbor overnight.

"How is it?" Yan Chujie lifted the tent curtain and walked in, and asked Qian Tiandun and Wang Tom, who had just returned to Hong Kong. When he was woken up by the orderly just now, he saw that the time was four o'clock in the morning, and at this time, except for a few guards, the entire Yongan Port was still asleep.

"There are some small discrepancies between the second alternative site and the information we have at hand, but we believe that the operational needs are fully satisfied, and we can consider the second alternative site as a second battlefield. Qian Tiandun reported succinctly.

"It's normal for there to be discrepancies, the maps we have are centuries from now, and the coastlines of these coastal areas will definitely change over the course of a few hundred years. Yan Chujie looked at the slightly tired faces of the two under the light, stopped talking and called the orderlies in: "Go and inform the kitchen, make some hot food and send it over, hurry!"

"Let's talk about our reconnaissance of this area first!" Qian Tiandun was still in the excitement period at this time, and spread out the map to Yan Chujie and began to explain.

"The width of this pass is only two hundred meters, which is about a quarter of the width compared to Candidate No. 1 to the south, which means that we can put four times as many troops on a unit-length line of defense without worrying about being attacked from the flank. Qian Tiandun pointed to the map and explained: "The South Vietnamese military camp is still some distance from this pass, and the pass is located right behind their main camp. ”

"What if the other side chooses to attack from the north and south?" Yan Chujie asked.

"It's unlikely, because there's a flat offensive path down the hill to attract their attention, and I'm afraid they won't use the way up the hill until they're in pain. We will set up early warning observation posts at the high ground, and if necessary, we will retreat to the coast and rely on the beachhead and the cover of artillery fire from the ships to attack the adversary. The area of this area is too small, and although the South Vietnamese Army is numerous, it has a limited attack surface that can pose a threat to us. Tom Wang immediately answered Yan Chujie's question.

"In addition, while we open up a second battlefield to attract the attention of South Vietnam, we can also go to their rear to attack supply lines. Qian Tien Dun added: "Based on what we have learned, the South Vietnamese army does not have much grain and grass on the front line, and their transportation capacity is limited, once there is a problem with the supply line, it will soon cause a chain reaction that will affect the combat effectiveness of the front troops." At that time, let my company go to fight for the river for three to five days, and cut off their logistical supplies, and it is estimated that the life of the South Vietnamese Army will not be easy. ”

"But there was one thing we had to prepare for in advance, the beach was too shallow for a marina and we might need to choose a floating trestle for our landing. Tom Wang reminded: "The trestle is a semi-finished product from the main operation, but the small boat that built the bridge may have to be requisitioned to North Vietnam." ”

"I will do my best to communicate this matter with the North Vietnamese side after dawn. Yan Chujie nodded and wrote down the matter: "In addition, the North Vietnamese side has agreed to transfer a group of spearmen to cooperate with our actions. But the specific arrangement of where to board the ship is still coordinating with the Ministry of Shipping. ”

After Zheng Ting and the others arrived at the front line, they immediately proposed to Zheng Bai to transfer at least 1,000 spearmen to cooperate with the operation. Of course, this group of spearmen really had to cooperate with not the Hai Han militia, but the North Vietnamese trained troops. Spearmen were indispensable in the combat methods designed by the Military Police Department for this trained unit, and due to the haste of the departure, the North Vietnamese side did not equip this unit with corresponding spearmen, so they had to temporarily transfer personnel from the front line.

However, the base camp was fully prepared for this, and even prepared more than 1,000 wooden iron spears more than four meters long in advance, which were transported by ship this time, and even the weapons did not need to be prepared by the North Vietnamese side, as long as they directly contributed to the force, which is probably one of the reasons why Zheng Bai agreed very happily. The only thing that made the command a little uneasy was that this improvised spear unit had never trained with the North Vietnamese musketeers, and the first time they cooperated, they had to go directly to the battlefield, and the combat effect might not be too ideal.