General Discussions
This is the place to discuss general issues related to the U-boat war or the war at sea in WWII.
Re: Technical details
Posted by:
ROBERT M.
()
Date: August 06, 2002 03:29PM
<HTML>Parade:
At slow speeds, because all shipboard control surfaces, like bow or fairwater
planes and rudder are reversed It takes some delicate training to achieve the ability
to "steam" backwards, don't you agree?
In July, 1981, during sea-trials of the USS LA JOLLA (SSN-701) Admiral Rickover
gave a "crash-back" order. The helmsman threw the submarine into high-speed reverse to bring LA HOLLA from full forward speed to a quick stop. It was like
stomping on the brakes of a 7,000-ton truck in the middle of the freeway. Every piece of equipment in the engine room went to full stress as the turbines and gears reversed direction and strained against the forward momentum of the ship. Under the pull of reverse thrust, LA JOLLA slowed quickly.
Rickover was in charge of giving the order for "all ahead" after the boat came to a full stop. If he was even seconds late in giving the order, the full reverse thrust of the propellor would instantly drag the boat into reverse speed. Submarines were not designed to go backwards. Sternway, as it is called, is dangerous because the stern of the ship was where all the weight was packed, and a little down angle could quickly drag the boat too deep too fast.
"Ship dead in the water" as reported over the 1MC (public address system) by the XO in the Control Room. But there was no "all ahead" order from Rickover. LA JOLLA quickly developed five knots of reverse speed and the depth of the boat
slipped sixteen feet. "All ahead" was heard over the speakers, but the order had
not come from the Maneuvering Room. Someone had usurped Rickover's authority.
Rickover bellowed from his station in the Maneuvering area to conduct the test again..Godammit, he was going to give the order.
The whine from the turbines built slowly. LA JOLLA went to flank speed again, cutting through the ocean at narly 40 MPH.
After a few minutes of high-speed running, Rickover gave the "crashback" order a second time and the boat lurched into the braking position. When speed had decreased to three knots, the navigation center announced "Ship dead in the water" over the 1MC.
But Rickover waited. And Waited. His silence dared anyone to give the "all ahead" order before he was ready. Seconds passed and the crew members who knew what was going on were prespiring. LA JOLLA continued full reverse thrust for 180
seconds. The reverse speed indicator climbed to over 10 knots, then past 11 knots to nearly 12 knots. The angle of the boat was noticeable. They were going down by the stern, going down fast. The newcomers aboard flinched visibly as
the hull popped loudly. It was the pressure-loading across the steel skin. The
Atlantic tightened its grip as they slid deeper and deeper. Finally Rickover ordered
forward speed, but the whiplash action of the change in water flow over the diving
planes threw the nose of the boat into a diving angle. Within seconds, LA JOLLA was plummeting again through the Atlantic in a bow dive that was 40 degrees below
the horizontal. Loose gear and equipment crashed and clanked to the deck throughout the boat, the noise tearing at raw nerves and adding to the feeling of
panic. Crewmen lost their footing. Some yelped with pain as elbows, shins, and knees slammed into metal to break their fall. Even Rickover was surprised and reached for hand-holds to keep from losing his dignity on the deck of the Engine Room.
In the 5 or 6 minutes that she was out of conrol, first sliding down by the stern and then in the hard dive by the bow, LA JOLLA had fallen another 240' to a depth of 600'. They had nearly dived to the sandy bottom and that might have been the end
for all of them.
LA JOLLA was one boat length away from the lower limit of her operating depth. In a few more seconds the boat would have been up against her crush depth, and that would have been it--another THRESHER, but this time by Rickover's hand and with Rickover aboard.
He had been wrong to do what he did, and everybody knew it, but they treated it delicately because it was Rickover and because he was 81 years old. That was the
point. What the heck was he doing putting nuclear-powered attack boats through
full stress maneuvers at that age? Had he forgotten to give the "all ahead" order?
Had he forgotten that a 688-class boat could not dive to 1300' as the 637-class
could? It was more likely that he was being bull-headed, that he was only thinking about asserting his authority and not about how quickly the loss of control could
throw the boat to depth where the ocean would find a chink in the pressue hull and
bore through it with a cutting power that could split a man in two and part steel like
butter.
Hope this excerpt from "RUNNING CRITICAL by Partick Tyler - 1986, will give all
an idea why driving a submarine backwards is too risky, even with "super planes-
men" at the diving controls.
Later,
ROBERT M.</HTML>
At slow speeds, because all shipboard control surfaces, like bow or fairwater
planes and rudder are reversed It takes some delicate training to achieve the ability
to "steam" backwards, don't you agree?
In July, 1981, during sea-trials of the USS LA JOLLA (SSN-701) Admiral Rickover
gave a "crash-back" order. The helmsman threw the submarine into high-speed reverse to bring LA HOLLA from full forward speed to a quick stop. It was like
stomping on the brakes of a 7,000-ton truck in the middle of the freeway. Every piece of equipment in the engine room went to full stress as the turbines and gears reversed direction and strained against the forward momentum of the ship. Under the pull of reverse thrust, LA JOLLA slowed quickly.
Rickover was in charge of giving the order for "all ahead" after the boat came to a full stop. If he was even seconds late in giving the order, the full reverse thrust of the propellor would instantly drag the boat into reverse speed. Submarines were not designed to go backwards. Sternway, as it is called, is dangerous because the stern of the ship was where all the weight was packed, and a little down angle could quickly drag the boat too deep too fast.
"Ship dead in the water" as reported over the 1MC (public address system) by the XO in the Control Room. But there was no "all ahead" order from Rickover. LA JOLLA quickly developed five knots of reverse speed and the depth of the boat
slipped sixteen feet. "All ahead" was heard over the speakers, but the order had
not come from the Maneuvering Room. Someone had usurped Rickover's authority.
Rickover bellowed from his station in the Maneuvering area to conduct the test again..Godammit, he was going to give the order.
The whine from the turbines built slowly. LA JOLLA went to flank speed again, cutting through the ocean at narly 40 MPH.
After a few minutes of high-speed running, Rickover gave the "crashback" order a second time and the boat lurched into the braking position. When speed had decreased to three knots, the navigation center announced "Ship dead in the water" over the 1MC.
But Rickover waited. And Waited. His silence dared anyone to give the "all ahead" order before he was ready. Seconds passed and the crew members who knew what was going on were prespiring. LA JOLLA continued full reverse thrust for 180
seconds. The reverse speed indicator climbed to over 10 knots, then past 11 knots to nearly 12 knots. The angle of the boat was noticeable. They were going down by the stern, going down fast. The newcomers aboard flinched visibly as
the hull popped loudly. It was the pressure-loading across the steel skin. The
Atlantic tightened its grip as they slid deeper and deeper. Finally Rickover ordered
forward speed, but the whiplash action of the change in water flow over the diving
planes threw the nose of the boat into a diving angle. Within seconds, LA JOLLA was plummeting again through the Atlantic in a bow dive that was 40 degrees below
the horizontal. Loose gear and equipment crashed and clanked to the deck throughout the boat, the noise tearing at raw nerves and adding to the feeling of
panic. Crewmen lost their footing. Some yelped with pain as elbows, shins, and knees slammed into metal to break their fall. Even Rickover was surprised and reached for hand-holds to keep from losing his dignity on the deck of the Engine Room.
In the 5 or 6 minutes that she was out of conrol, first sliding down by the stern and then in the hard dive by the bow, LA JOLLA had fallen another 240' to a depth of 600'. They had nearly dived to the sandy bottom and that might have been the end
for all of them.
LA JOLLA was one boat length away from the lower limit of her operating depth. In a few more seconds the boat would have been up against her crush depth, and that would have been it--another THRESHER, but this time by Rickover's hand and with Rickover aboard.
He had been wrong to do what he did, and everybody knew it, but they treated it delicately because it was Rickover and because he was 81 years old. That was the
point. What the heck was he doing putting nuclear-powered attack boats through
full stress maneuvers at that age? Had he forgotten to give the "all ahead" order?
Had he forgotten that a 688-class boat could not dive to 1300' as the 637-class
could? It was more likely that he was being bull-headed, that he was only thinking about asserting his authority and not about how quickly the loss of control could
throw the boat to depth where the ocean would find a chink in the pressue hull and
bore through it with a cutting power that could split a man in two and part steel like
butter.
Hope this excerpt from "RUNNING CRITICAL by Partick Tyler - 1986, will give all
an idea why driving a submarine backwards is too risky, even with "super planes-
men" at the diving controls.
Later,
ROBERT M.</HTML>
| Subject | Written By | Posted |
|---|---|---|
Technical details
|
Io Chrysafidou | 08/04/2002 06:13PM |
|
Re: Technical details
|
joe brandt | 08/05/2002 01:21AM |
|
Re: Technical details
|
Parade | 08/05/2002 08:11PM |
|
Re: Technical details
|
Mikko | 08/05/2002 09:42PM |
|
Re: Technical details
|
Parade | 08/06/2002 08:18AM |
|
Re: Technical details
|
ROBERT M. | 08/06/2002 03:29PM |
|
Re: Technical details
|
bert bailey | 06/09/2016 01:37AM |
|
Re: Technical details
|
ROBERT M. | 08/06/2002 02:52AM |