Updated: May 2
After many transfers of troops and people from the Central region, HQ 402 entered the shipyard for minor repairs. The technical condition of HQ 402 should have been a major overhaul; but because of the Fleet Command's plan, HQ 402 was only given a minor repair status. Since the ship was being repaired, both the Captain and the Vice Captain were absent. The crew of HQ 402 is only about 50 personnel, 10 Second Lieutenants, and one mechanical officer – Lieutenant Cao The Hung.
On the morning of April 30, at about 6:30 a.m., the order called for all officers and crew members of the battleship undergoing repairs to gather at Fleet Command. A senior officer in the Navy announced the dissolution of the Navy. As the senior officer present, Lieutenant Cao The Hung ordered Second Lieutenant Ninh - the security officer - to break the lock of the Captain's room, take the money in the safe and give it to the staff so that they can do whatever they want. The staff sadly left the ship, leaving only one corporal, one first corporal, and one non-commissioning officer, because they couldn't go home.
At this time, many thousands of people poured into the Navy Shipyard and poured onto HQ 402. After declaring that the ship was damaged, Lieutenant Hung left the battleship and headed to Bach-Dang wharf. At Bach-Dang wharf, seeing that Viet Cong tanks were entering the Me Linh construction site and hearing a lot of gunfire, Lieutenant Hung returned to HQ 402.
After returning, Lieutenant Hung saw that among the people on HQ 402 was Lieutenant Thuoc, from HQ 402; some officers of the 19th class of the Navy; Second Lieutenant Hai, in the same branch as Lieutenant Hung, and many Colonels of the Infantry. They all asked Lieutenant Hung to repair HQ 402 to evacuate. Knowing how badly damaged HQ 402 was, Lieutenant Hung thought to himself that he could not fix it; he sneaked ashore. As soon as he put the key into the Jeep, Lieutenant Hung was pulled by many people and brought back to HQ 402.
This second time, Lieutenant Hung met his professor Triet - Father Huynh - principal of Hung-Dao high school in Saigon. Lieutenant Hung explained to Father Huynh: 24 batteries of the battleship are all out of juice and need to be charged. Each battery is huge and heavy. If it is sent to the Navy Factory, it will take about a day to charge each battery! In addition, the electric compass (Gyro Compass) at the bridge has been removed and taken to the Navy Corps to be repaired a few days ago. Lieutenant Hung told Father Huynh, with the moral responsibility for all 2,000 people on HQ 402, Father Huynh should ask everyone to leave the battleship because the battleship is out of use and the Viet Cong are entering the Naval Yard.
After Father Huynh announced, everyone on board agreed to stay and die together with HQ 402! Faced with such a situation, Lieutenant Hung had to mobilize all men and young people to help. He placed the Colonels in charge of security and asked many young people to move the electric machines according to his instructions. After hours of repairs, one engine started up, but oil was sprayed everywhere. Lieutenant-Lieutenant Hung told everyone to take clothes and bed sheets and wrap them around the oil pipes. When the main engine started up, Lieutenant Hung immediately turned off all electrical systems - except for the engine fan.
By 3 pm on the same day, the engine ran smoothly. Lieutenant Hung told everyone to take all the buoys from the empty battleships and bring them to HQ 402. Lieutenant Hung chose a number of muscular young men - whether they were Navy or not - to steer the ship; Another group lined up one from the command post to the engine tunnel to pass on voice commands. After instructing the youth group to turn the steering wheel to the right and to the left, Lieutenant Hung ran up and down the command post and engine tunnel, trying to bring the battleship to the river.
Out to the river, Lieutenant Hung ordered "advance 5". The word-of-mouth transmission from the bridge to the command post took a minute each time. The inexperienced crew steered the rear of HQ 402 crashing into the Marine floating club. Then Lieutenant Hung quickly shouted "right 5". The group of young drivers turned the steering wheel so that the bow of the battleship crashed into Thu Thiem, damaging some houses on stilts! For every "right 5", and "left 5", HQ 402 turns around in front of Me Linh construction site but can't run straight.
Afraid of being shot by the Viet Cong, Lieutenant Hung told everyone to lie down on the deck of the battleship, so as not to let the Viet Cong see. At the same time, Lieutenant Hung took a white shirt and told the Marines to tie the flag and pull it up.
On the Me Linh construction site, the Viet Cong thought that HQ 402 was coming from afar, so they waved their hands in greeting. On the battleship, the Marines also pretended to wave and cheer. After nearly an hour of wandering around in front of the Me Linh construction site, HQ 402 finally slowly "crawled" straight. From the Majestic restaurant to Nha-Be, HQ 402 picked up many more people from the small boats running along the sides of the ship.
Around 5 pm, when arriving at Soai Rap river, HQ 402 met HQ 601 coming back. The Captain of HQ 601, Navy Captain Tran Van Chanh, told Lieutenant Hung not to go to Vung Tau, the Viet Cong had blocked it. The ship Viet-Nam Thuong-Tin carrying refugees was shot at in the morning.
At the confluence of the Soai Rap River, Lt. Hung saw PBR groups and various types of Navy personnel on shore and thought he could use their help. So he asked Second Lieutenant Hai on HQ 402 to radio to find Colonel Dung, asking Colonel Dung to take HQ 402 out to sea.
From LCM8 Colonel Dung came onto HQ 402. After reviewing the status of HQ 402 and listening to Lieutenant Hung's presentation, Colonel Dung also shook his head, admiring those who had the tenacity of bringing HQ 402 here! After the test drive, seeing that HQ 402 would turn 30 degrees every once in a while - because word-of-mouth orders from the command post to the cockpit took time - Colonel Dung was uncertain that he could guide HQ 402, even with his extensive maritime experience.
At this time, Lieutenant Hung mobilized another team to bail water, because the water flooded the engine room. At the same time, Vice Deputy Doctor Nghiem Van Phu, Doctor Tran Quoc Dung, and many soldiers of the Navy Army came onboard the ship.
On the morning of May 1, after a long time, Colonel Dung was able to guide HQ 402 to the sea. A Destroyer - belonging to the US 7th Fleet - saw that HQ 402 would turn 30 degrees after running for a while and they knew there was an abnormality. This Destroyer wanted to come and support HQ 402. But when the Destroyer was just approaching, met HQ 402 turning, almost bumping into the Destroyer, Destroyer panicked, pulled the whistle, and ran.
At this time, people on the ship discovered the presence of two Americans on HQ 402. Many Vietnamese people were upset, thinking that the US had abandoned South Vietnam, and wanted to kill these two Americans. Lieutenant Hung brought the two Americans up to the bridge, protecting them. Colonel Dung asked these two Americans to call the Seventh Fleet for help, but these two Americans do not know the communication frequency of the 7th Fleet-Flotilla.
Colonel Dung called Vice-Admiral Cang to present the status of HQ 402. Former Commander of the Fleet and Navy Colonel Nguyen Xuan Son told Colonel Dung to try to bring HQ 402 as close as possible to Con-Son island, there will be another battleship to help.
On the morning of May 2, the Destroyer returned and via radio contact asked Colonel Dung about the status of HQ 402. After listening to Colonel Dung's presentation, Destroyer Captain transferred to HQ 402 a team of technical experts. After 20 minutes of observation, the team of experts presented it to the Destroyer Captain. The Destroyer Captain presented it to the Commander-in-Chief of the U.S. 7th Fleet.
The order to remove everyone from HQ 402 is issued. HQ 2 was ordered to pair close to the side of HQ 402 for compatriots and friends to switch over. Then HQ 6 was paired to transfer the remaining people on the ship.
After the ship was emptied, the bell rang several times to confirm that no one was onboard HQ 402, and the order to sink HQ 402 was executed.
At 3 pm on May 2nd, two warships belonging to the 7th Fleet of the United States Navy sank Hai Vang Lam Giang HQ 402.