Nuclear submarines are strategic weapons that can hide in the deep sea and travel the oceans. Its emergence is one of the most significant achievements in the development of human science in the 20th century. Because of this, when the news of the successful launch of the world's first nuclear submarine from New London to San Juan in May 1955 came out, it immediately shocked the world like the atomic bombs dropped by the United States on Hiroshima and Nagasaki in World War II. On April 10, 1963, the American nuclear submarine "Longtail Shark" was sunk in a flight test after the overhaul, and all 108 officers and soldiers and 21 other personnel died, which also shocked the world.
<h1 class="pgc-h-arrow-right" data-track="2" > deep diving test failed</h1>
The "Longtail Shark" is the first submarine of the third generation of attack nuclear submarines in the United States, which began construction on May 8, 1958 and was launched on July 9, 1960, is a beautiful teardrop nuclear submarine, with a surface displacement of 3750 tons, an underwater displacement of 4310 tons, a length of 84.9 meters, and a width of 9.67 meters. It is equipped with an advanced attack weapon, the Shablok rocket to fly torpedoes (6.4 meters long, 533 mm in diameter and weighing 1853 kg), which can carry nuclear warheads or ordinary torpedoes with a TNT equivalent of 20,000 tons. When launched, the submarine can be hydraulically pushed out of the 533 mm torpedo tube underwater, and after 1 second the rocket is ignited underwater, exiting the water at an elevation angle of 30 ° to 40 °, flying to the target at supersonic speed in the air, with a maximum flight distance of about 26 nautical miles, which can launch a pre-emptive attack on the enemy ship and have a greater deterrent effect.
On April 9, 1963, the "Longtail Shark" successfully concluded its shallow sea trial after being overhauled. At 6:35 a.m. the next morning, the Longtail Shark sailed at periscope depth 220 nautical miles east of Boston on the vast Atlantic Ocean. Soon, it will be doing a deep diving test of more than 300 meters. The captain, Major Harvey, was very pleased with the performance of the Longtail Shark. He knew it was the most advanced attack nuclear submarine in the U.S. Navy. As he turned the periscope to observe the sea, the figure of the submarine lifeboat Skylark suddenly appeared in his field of vision, and its gray-brown figure fell into the valley of the waves from time to time and jumped on the peak of the waves.
Sonar soldiers reported the precise distance between Skylark and Longtail Shark. Captain Harvey nodded. He looked at the astronomical clock on the bulkhead, and it was 7:47. He picked up the No. 1 microphone and gave the order to the submarine commander to dive. At the same time, the liaison officer spoke to the Skylark through an underwater acoustic telephone.
"Skylark, I'm the Longtail Shark, and I've started diving."
"The Skylark understands."
Here is a series of calls between the Longtail shark and the Skylark:
0747 began a large deep dive.
0809 Safe dive depth at half.
The 0835 is 90 meters away from the test depth.
0853 reached the test depth.
The trial is proceeding smoothly.
The 0912 two ships communicated at regular intervals, and the 0913 Skylark received a report of the floating status and heard the sound of blowing out the ballast water tank with high-pressure air.
0914 Skylark call: Your boat is in poor condition, please tell us about depth, heading and speed.
No answer.
Then, the Skylark called: Can it be manipulated?
No answer...
0917 "Skylark" received: has exceeded the depth of safe submarine.
The Lark then continued to call, but there was no news.
Shortly thereafter, the Sonar soldiers of the Skylark seemed to hear the crushing sound of liquid.
Major Heiko, the captain of the Skylark, looked into the microphone for a long time, and all the officers and men in the command room held their breath and listened. After a while, Heiko said in a low, slow tone, "It looks like it was shipwrecked." "The commander, who was born and died in World War II, couldn't have been more clear about what the sound coming from underwater meant. However, at this moment, he still held the psychology of luck and continued to call the "long-tailed shark" for a while, answering him with the silence of the sea and the faint rustle of the telephone.
<h1 class="pgc-h-arrow-right" data-track="23" > sink into the abyss of death</h1>
The sea area of the Longtail Shark test is far from the continental shelf and has a water depth of about 2700 meters. When the "Longtail" loses control, it will sink into the abyss of death; when the depth exceeds 1000 meters, the huge sea pressure will crush the hull, so the nuclear submarine becomes an iron coffin for all the personnel to die on the seabed. With no crew surviving and the submarine crushed by the sea, it is difficult to pinpoint the real cause of the Longtail Shark's crash. The following explanation can only be made on the basis of incomplete physical information and expert speculation.
The report of the special committee investigating the cause of the accident of the "Longtail" presumed: "I am afraid that somewhere in the seawater pipeline, perhaps in the rear cabin, some kind of damage has occurred; Whatever the reason, in the case of diving depths, the pipeline can not withstand the high pressure of hundreds of atmospheres in any case. Seawater was first sprayed into the cabin from the damaged area, causing the power system to be destroyed first; after the power outage, the submarine lost control and quickly sank until it collapsed.
Here's what experts described for the sinking of the Longtail Shark:
At 7:47, the Longtail Shark was at periscope depth — about 20 meters. After Major Harvey ordered the dive, the submarine drifted down at a longitudinal inclination of 5 degrees, reaching a depth of 130 meters at 8:09, which was half the reported depth of safe diving underwater at that time.
At 8:10, the Longtail Shark continued diving, reaching a depth of about 200 meters after 25 minutes, and the Lark received calls from it became lighter and lighter.
At 8:53, reaching a test depth of 300 meters, it was successfully waving at the "Longtail Shark".
At 9:12, a loud noise suddenly came from the cabin. "Not good!" Captain Harvey hurried toward the cabin, only to see a stream of seawater gushing into the cabin at a pressure of 30 atmospheres — an unimaginably dangerous level compared to a fire faucet with a spray pressure of 3.5 atmospheres. The captain may order the crew to plug the leak. However, the strong spray makes people unable to open their eyes, and the noise of the spray makes people unable to listen to the command. In the face of death, the engineers were helpless.
At this critical juncture, the captain ordered the emergency blowing and reported to the Skylark that it had entered a floating state. The Lark did hear the blowing of high-pressure air, and the submarine once floated.
A large amount of seawater poured into the engine room from the cracked seawater cooling pipe, and some of the cables to the nuclear reactor were already immersed in seawater, and the situation was very serious! The captain suggested shutting down the reactor, the captain agreed, and the propeller stopped turning. Due to a large amount of seawater entering the cabin, the buoyancy generated after the high-pressure air blows away the ballast water tank is no longer used, the submarine continues to sink, the depth gauge pointer has exceeded the dangerous red line, and the submarine will be crushed to pieces in an instant.
Captain Harvey pinned his hopes on the last trump card, which was to use the waste heat of the reactor steam generator to re-spin the main engine.
"Start the host now!" He gave the order.
Doing so can damage the reactor shell. Harvey knew this, but he had few other options.
At 9:17, just when he finally reported to the "Skylark" that it exceeded the safe submarine depth, the main engine had not yet had time to start, more than 1,000 tons of seawater poured into the engine room, and the crew was instantly killed by high-pressure air pressure of fifty or sixty atmospheres.
The "Longtail Shark" continues to drift into the abyss...
An oceanographer on the Commission of Inquiry gave another explanation for the sinking of the Longtail Shark: in the Atlantic Ocean east of Long Beach, the seabed formed an irregular submarine canyon that separated from the continental slope, known as the East Strait of the Seabed. It is the largest outlet from Maine to the Atlantic Ocean and usually has weak ocean currents. Due to the impact of the big storm on April 4, the situation in the sea has changed drastically, and the cold and warm currents have interlaced, forming a terrible "storm in the sea", which is a large whirlpool in the sea with a height difference of 100 meters, and once the submarine is involved, it is very difficult to maneuver. If you struggle in the vortex, you will inevitably lose your three-dimensional balance and sink downwards.
When the "Longtail Shark" was killed, due to a storm in the sea, all measures to try to float failed, and the huge whirlpool quickly swept it into the abyss of death.
<h1 class="pgc-h-arrow-right" data-track="40" > shocked the Pentagon</h1>
At 11:04 on the day of the accident, the U.S. Department of the Navy received an urgent telegram from Major Heiko: the nuclear submarine "Longtail Shark" disappeared at 9:17 today.
The Pentagon was shocked to hear the news of the crash of the Longtail Shark! The Admiralty quickly drew up contingency plans and sent a large number of ships to investigate the wrecked sea area in order to find out the cause of the sinking.
The day after the accident, the first step in the investigation plan was carried out: "Send out the investigation ship's sonar and underwater cameras to search." It's a needle in a haystack, a vast sea, where is the wreckage of the Longtail Shark? The intense search continued for several days. The camera was dragged close to the bottom of the sea to search, and it hit a small rocky mound on the bottom of the sea, and several of them were damaged. On the film that was washed out, it was only a bizarre and strange rock on the seabed, leaving no trace of the "Longtail Shark".
The Pentagon was very anxious. The investigation cannot be postponed any longer. Therefore, the second step of the investigation plan was carried out: directly to the depth of 2700 meters to investigate. At that time, only one "Trieste" could descend to such a large depth in the United States, and it was also conducting marine surveys on the Other side of the Pacific Ocean. The Navy issued an urgent order to transfer it to the Atlantic, but it took more than half a month to reach the scene.
The crash of the "Longtail Shark" dealt a heavy blow to the US Navy and learned an extremely profound lesson, for which the US Navy quickly took the following two measures:
1. Strictly inspect the seawater pipelines of all U.S. submarines, and conduct a strict safety inspection of all welds in the pressure-bearing parts.
2. Develop a new type of deep-diving life-saving system, that is, a deep-diving lifeboat with a working depth of 1500 meters.
<h1 class="pgc-h-arrow-right" data-track="48" > the abyss to look for wreckage</h1>
The Trieste submersible has long been famous in the world - on January 23, 1960, it dived to 10,916 meters in the Mariana Trench in the western Pacific Ocean, setting a world record for deep diving.
On 14 April 1963, the fourth day after the crash of the Longtail Shark, it received orders to be dragged out of the Eastern Pacific by the Challenger landing craft. Take the Panama Canal to the Atlantic Ocean. Due to the wind and waves during the voyage, there was some delay, and it took half a month to reach the waters east of Boston.
In order to enable the Trieste to successfully complete the underwater investigation mission, in addition to the emergency repair of the original equipment, it was equipped with the most advanced search sonar and radiometer of the time, in order to improve the underwater search capacity and identify the possible degree of harm of the terrible nuclear reactor with rice.
When everything was ready, on 10 June, the "Trieste" was piloted by Lieutenant George Martin and his companion Kenneth Mackenzie into the underwater abyss. Martin carefully maneuvered the submersible and slowly drifted down to the bottom of the sea at a depth of 2700 meters. When approaching the bottom of the sea, MacKenzie pressed the electric button that released the adjustment cable, allowing a thick iron chain to fall slowly - when part of it touched the seabed, the deep submersible increased a certain amount of buoyancy and stopped diving. In this way, the deep submersible can make a fixed deep voyage near the seabed, and its bottom can avoid hitting the bottom.
Although the deep submersible has made some modifications before diving, it still seems to be relatively clumsy, and it is difficult to change the course no matter how it is manipulated underwater. 4 hours passed, and only a short distance was advanced. Through the thick observation window, the two dive pilots saw only a monotonous seabed, and found no clues, so they had to float to the surface of the sea in disappointment.
On 22 June, the Trieste was residing for the second time. This time, it was diving down the current, walking faster than the last time. It is still sailing close to the bottom of the sea, and under the strong searchlight, everything under the seabed can be seen clearly. 2 hours passed, still nothing was found. Suddenly, the driver spotted a suspicious target on a fluorescent screen searching for sonar. They were so excited that they activated all the thrusters on the submersible. Constantly correcting course, struggling to get closer to the target. Illuminated by a searchlight, it became clear that it was a large piece of metal, and the camera immediately captured this enticing shot. Excited investigators continued to wander around the neighborhood to see what else they could find. Unfortunately, the deep submersible was trapped in a quagmire, tightly attached, and unable to move.
The accident almost killed the two. They constantly shake the submersible and throw a part of the steel ball in order to increase the buoyancy of the submersible. After half an hour of hard work, the "Trieste" finally broke out of the mud siege, and finally jumped up gently, escaped and soared upwards. Martin hurriedly released 1,000 gallons of gasoline from the float to reduce the buoyancy of the boat and slow down the ascent.
The two pilots then inspected the gauges in the pressure-resistant cabin and continued to search for the wreckage of the Longtail Shark. The seabed is dry and gray, with the occasional angular sparkle. The submersible was slowly moving forward, and Mackenzie sat in front of the observation module, intently watching the crystal blue world, but still nothing was gained.
The next day, the Trieste dive for the third time, and apart from finding a small piece of metal, there were still no major discoveries. A full week has passed, the whereabouts of the Longtail Shark are still unknown, and the Trieste has been towed back to port for maintenance and equipment updates.
In late August, the Trieste, armed with the latest equipment, sailed to the wrecked waters of the Longtail Shark. On the first dive voyage, the most important discovery was a plastic shoe cover. It was worn by the reactor room staff on the nuclear submarine, and the number on it, SSN-593, could be seen through the porthole, an important discovery that gave hope to investigate the cause of the crash of the "Longtail Shark", indicating that the wreckage of the nuclear submarine was nearby.
Martin and MacKenzie were greatly encouraged and continued their search in the immediate vicinity the next day. Suddenly, the submersible shook and spun violently. The siren on the console is red, the buzzer is "beeping, beeping", the collision avoidance sonar warns of danger... Martin and Mackenzie, sitting in the pressure-resistant ball, judged that they had encountered a whirlpool under the sea. They immediately aimed ahead to scan and found a huge obstacle, most likely an undersea hill. Saying that it was late and fast, McKenzie immediately pressed the first and second electric buttons, threw out a part of the ballast iron ball, and the buoyancy of the deep submersible increased rapidly, crossing a black pressure mountain shadow, and the two were relieved. The Trieste floated up to the surface of the sea and returned to the sun-drenched sea.
Then, the Trieste made several more dives, but none of them were significant.
On 29 August, the Trieste dived to the bottom of the sea where the Longtail Shark was buried. Martin drove cautiously. Mackenzie sat in front of the observation window and stared at the bottom of the sea. Suddenly, he saw pieces of metal, broken cables, crooked and twisted pipes... Mackenzie almost jumped up in delight, and after much effort, they finally found a piece of the wreckage of the Longtail Shark, which was scattered on a large piece of the seabed. This shows that the "Longtail Shark" was crushed to pieces by crushing and exploding before sinking to the bottom of the sea.
MacKenzie took many photographs at the scene and picked a cracked tube with a robotic hand and put it in the submersible's sampling basket. The Trieste finally surfaced. As soon as the heavy hatch cover opened, pilot Martin was the first to climb up from the pressure-resistant ball. He stood on the deck of the deep submersible, stretched his arms, let the sea breeze caress his open chest, combed his slightly disheveled hair, and excitedly beckoned to his companions.
The pipe fished from the deep sea is a 1.7-meter-long copper pipe weighing 4.5 kilograms, with the stamp of SSN-593 on it, which was identified by experts at the scene and proved that it was a hot water flushing pipe in the kitchen of the "Longtail Shark". There was also a blast opening left on the pipe, presumably bursting due to the increase in pressure when the cabin was filled with water.
Since the robot lifting load on the submersible is relatively small, it is not possible to salvage large steel plates and other objects. However, the "Trieste" salvaged a problematic tube from a depth of 2700 meters, which is indeed a remarkable feat, and it has made a new contribution to solving the mystery of the disappearance of the "Longtail Shark".
In the logbook of the "Trieste", after setting a world record for deep diving, a new chapter was recorded revealing the tragic fate of the "Longtail Shark", which also proved its value in working in the deep sea.