The Japanese army participated in the Changsha Campaign this time, and the flight unit under the direct command of Commander Anan Weiji was the Japanese Army's Third Flying Group, and the chief officer was Lieutenant General Guan Yuan Michitai, the commander of the group. It has the first flight regiment and the third flight regiment under its jurisdiction, and the two flight regiment commanders are Major General Toyoji Akiyama and Major General Saburo Endo. The two squadrons consisted of four reconnaissance aircraft squadrons, two fighter squadrons, four light bomber squadrons, two heavy bomber squadrons, and four independent squadrons.

After receiving the order to carry out a large-scale bombing of the positions of the China Army along the Liuyang River, the flight unit first sent a light bomber squadron and a heavy bomber squadron to the direction of the 3rd Division, and a fighter squadron to escort the troops. The light bomber squadron has 36 Type 96 attack aircraft (that is, bombers, which the Japanese call ground attack aircraft), and the heavy bomber squadron has six of the latest Type 1 heavy attack aircraft.

Early in the morning of 7 January, the roar of engines came from the sky north of Liuyang River, and the officers and men of the 544th Regiment guarding the position knew that it was a Japanese plane that had made a sortie. Brigade commander Tang Yiqun had long been prepared for the Japanese army to send planes to help in the battle, and as soon as he gave the order, all the officers and men on the position hid in the air-raid shelters. The officers and men of the 90 th Division, who had endured countless bombings by Japanese planes, knew that the power of aerial bombs was much greater than that of artillery shells, and in addition, they were thrown from the air, and the air-raid shelters were almost repaired, and they could not withstand the bombing of aerial bombs at all.

As a result, the dugouts were dug deeper, and the tops were reinforced with steel plates and concrete layers to ensure that they could withstand the bombardment of heavy aerial bombs. The air-raid shelters are mainly built behind the forward positions, and there are communication trenches that can lead directly to the forward positions. Therefore, as long as a few observation posts were placed on the forward positions, they could all enter the bombing shelters to avoid the bombing of the Japanese planes.

The 90 th Army did not have a lot of air defense weapons, not to mention the Type 6 or 7 heavy machine guns that could fire at the air, and even more than 200 anti-aircraft guns, but Wang Haitao did not put them on the peripheral positions. There was an anti-aircraft artillery battalion placed on the Yuelu Mountain, where the heavy artillery positions were related to the survival of Changsha City, and once the Japanese army found out, they would definitely send planes to bomb it, so there was only a small anti-aircraft artillery battalion there.

Wang Haitao finally wanted to put the Japanese army under the city of Changsha, in the brutal urban offensive and defensive battles, it was also necessary to effectively control the bombing of Japanese planes, so Wang Haitao chose two of the hills close to the city wall of Changsha City, put an anti-aircraft gun battalion on each hill, and dozens of anti-aircraft guns were also distributed on the city wall. Wang Haitao arranged the anti-aircraft weapons belonging to other divisions in several important departments in the city to deal with the Japanese planes that flew over the city.

Without antiaircraft guns, which are a weapon of mass destruction against Japanese aircraft, if only heavy machine guns are used to fire at the air, first, the effect will not be very good, and second, the loss of personnel and weapons will be too great. Therefore, Tang Yiqun did not make much preparations for air combat, but tried his best to build air-raid shelters of sufficient quantity and quality, and the Japanese planes would always fly back after dropping bombs, and as long as they were not bombed, there would not be much loss.

The Japanese planes flew into the air above the position of the 544th Regiment, and after the pilot planes confirmed the target, the commander who led the squadron gave instructions for attacking, and first four Type 96 attack planes swept over the position with a scream, and at the same time dropped a string of 50-kilogram bombs. Dozens of bombs exploded on the position, and dust and gunpowder smoke suddenly enveloped the entire position, and everything that could be burned on the position burned.

After these planes finished throwing bombs, they pulled up and took off, and several more Type 96 attack planes rushed down. The Japanese planes took turns to dive and bomb, and after all the bombs were dropped by the Type 96 IX. strike planes, six Type 1 heavy bombers flew over one after another. The bombs carried by the heavy bombers were different from those carried by the Type 96 attack planes, which carried 16 50-kilogram aerial bombs, while the Type 1 heavy bombers carried two giant aerial bombs weighing 500 kilograms each.

The explosion of an aerial bomb of 500 kilograms was truly earth-shattering, not only blowing up a crater with a diameter of 50 meters, but also throwing all trees and fortifications into the air within a radius of several hundred meters from the explosion site. Tang Yiqun and the others hid in the air-raid shelter, and they also felt the shock caused by its explosion, and even some soldiers fell to the ground unsteadily.

It took nearly an hour before the Japanese planes dropped all their bombs and began to return home. Listening to the sound of explosions outside, Tang Yiqun and the officers and soldiers of the 544th Regiment returned to the position, at this time, Tang Yiqun's eyes had no position in their eyes, and there were large and small craters one after another in the devastation. That is, the bomb shelters that took a lot of effort to build supported the bombardment, and other fortifications, even the bomb holes, were blown up, not to mention those sandbag bunkers and bunkers.

Several of the observation posts left on the ground were also killed in the air raid, much to the chagrin of Wei Hai, who sent them to stay. After seeing the big crater left by the explosion of the heavy bomb, even Tang Yiqun was taken aback, if the troops were still holding their positions, such a bombardment, I am afraid that there would not be a few people. While Tang Yiqun and the others were still patrolling the position, the Japanese heavy artillery and field artillery began to shell the position again.

Tang Yiqun and the officers and men of the 544th Regiment looked for a hidden place to avoid the artillery bombardment, but some soldiers fell under the Japanese artillery fire because they could not dodge or were unlucky. The Japanese artillery bombardment lasted for 20 minutes before stopping, and Wei Hai thought that the Japanese army would force the Liuyang River again, so he sent a battalion and a company to the forward position to keep an eye on the Japanese troops on the north bank of the river.

After half an hour, the Japanese troops on the north bank of the river still did not move, but the roar of planes was heard in the sky. All the people hurriedly hid in the air-raid shelter again, this time the number of Japanese planes was about the same as the last time, and it was nearly an hour of bombing, this time even the top of a bomb shelter was blown open, but fortunately it did not collapse, so there were no casualties.

For a whole morning, the Japanese army did not force the Liuyang River, but repeatedly bombed and shelled the positions of the 544th Regiment, and the positions no longer existed, and dozens of personnel were lost. After Tang Yiqun reported the situation to the division commander Tang Yikuan, Tang Yikuan personally went to find Wang Haitao. Because Zhang Lingfu's 272nd Brigade's position on the west bank of the Liuyang River was the same as that of the 271st Brigade, it was repeatedly bombarded by Japanese planes and heavy artillery in one morning, and the position became a ruin.

After hearing this, Wang Haitao understood that the Japanese army was in a hurry to cross the Liuyang River in order to launch an attack on Changsha City, and the battle plan was to put the Japanese army under Changsha City to fight, and there was no need to defend the bank of the Liuyang River, and the losses of personnel would increase in vain, and the 40th Division of the Army had already crossed the Liuyang River and exchanged fire with the 211th Division in Tongjing Town, so there was no need to defend the Liuyang River position.

Wang Haitao ordered all the two brigades of the 90th Division to retreat to the second position, and hold on to the second position until 10 p.m. on the 9th, and then withdraw to the third position. The order was transmitted by Tang Yikuan to the two brigade commanders, Tang Yiqun and Zhang Lingfu, and then conveyed by the two brigade commanders. Soon the troops had action, and Tang Yiqun led the 544th Regiment to retreat to a town called Jiangjiayuan on the northern outskirts of Changsha City. Zhang Lingfu led the 546th Regiment to retreat to the first-line position from Nanzhu Mountain to Fangshu Mountain, eight kilometers east of Changsha City.

Jiangjiayuan Town is attached to Changsha City is a not very large but more prosperous commercial town, there are many rich families in the town, built many deep house compounds, for safety, the rich households in the town raised funds to build a very strong city wall, there used to be a security team in the town to maintain law and order. But when they heard that the Japanese were coming, the people in the town either fled to the west of the Xiangjiang River or fled into Changsha City. As soon as Tang Yiqun arrived here, he fell in love with this town, persuaded all the few remaining people in the town to Changsha City, began to build fortifications here, and set up the brigade headquarters here.

However, Zhang Lingfu, the commander of the 272nd Brigade, made full use of the terrain. There is a row of horizontal hills between the Liuyang River and the east gate of Changsha City, the hills are not too high, the highest Nanzhu Mountain is more than 100 meters, but these hills are connected, the north is Nanzhu Mountain, the south is more than 80 meters of the Fir Tree Mountain, and the two mountains are continuous mountain beams for one thousand meters. A main highway goes around from the foot of Nanzhu Mountain to Changsha City.

Before Zhang Lingfu sent the 546th Regiment to guard the west bank of the Liuyang River, he took this row of hills as the main position, and built a large number of fortifications on the hills according to the terrain. Here the 547th Regiment was the main defensive task that he had previously led. Now that Zhang Lingfu withdrew to this line of defense with the 546th Regiment, he immediately adjusted the entire line of defense.

The main position of Nanzhu Mountain was defended by the 547th Regiment, and the position of Fangshushan was defended by the 546th Regiment. The original field artillery position placed on the top of Nanzhu Mountain was temporarily immovable, but 10 Gaoping dual-purpose twin heavy machine guns and 20 anti-aircraft guns mounted on automobiles were transferred to undertake the anti-aircraft mission.

After a morning of heavy artillery bombardment and aircraft bombing, the Japanese army saw that there was no movement on the defenders' positions, so they sent a small reconnaissance force to cross the Liuyang River to reconnoiter the situation. Soon the reconnaissance unit returned and reported that the defenders on the other side of the river had all retreated. The two division commanders were very pleased, and immediately sent troops to cross the Liuyang River to seize the opposite position, and then ordered the corps to quickly build a pontoon bridge so that the main force of the division could cross the river.

The engineer wing of the 6th Division had been prepared a day earlier, and it took an afternoon to build two pontoon bridges, and in the evening the 6th Division began to cross the river, and it was not until 10 o'clock in the evening that the 6th Division had all crossed the Liuyang River. The situation ahead was unclear, and the commander of the division, Lieutenant General Kanda Masashi, ordered to camp on the spot while sending many reconnaissance troops to search and reconnoiter under the city of Changsha.