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GPS COMPUTER VS SEXTANT/ASTROLABE/Old ways/manual
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He was just triangulating, by sight, points on different islands. He'd been piloting boats in that area since he was a kid. It was very smart of us to have him. He was a tremendously fun guy but brought a huge wealth of knowledge, not only of sailing but intimate knowledge of the entire area - from the sea bottom to the best bars. I remember being below decks eating breakfast one morning and a call came on the radio from another vessel "CSY - CSY...blah blah blah We've struck a reef". A coast guard ship had to be sent out to pull them off (at the time $5000min). They had gone bare boat (no skipper) and ours said smiling "I don't think they'll get their deposit back". Apparently not everything was marked on the nautical charts.
He also set us up for one of the most exciting things I've ever done in my life (and I've done a lot). We went from Admiralty Bay in Bequia to Mustique (where Mick Jagger's place is) but through two old whaling islands. The Islands form a funnel shape facing the open Atlantic and full size ocean waves enter but have no place to go but swell up into ginormous waves. He warned us to get ready. You enter the narrows calmly but within minutes the waves get inexorably bigger and bigger with the wind picking up even stronger until this 45 footer was angling up and down at +/-30°, every time coming down with a thundering crash and shudder that you thought surely the boat might break apart. Everybody was holding on for dear life to whatever they could find at hand. Then, as gradually as it built up, it eventually calmed back down but all of us were then talking at 90 mph about it as we were all so hyped up on adrenaline.
He also set us up for one of the most exciting things I've ever done in my life (and I've done a lot). We went from Admiralty Bay in Bequia to Mustique (where Mick Jagger's place is) but through two old whaling islands. The Islands form a funnel shape facing the open Atlantic and full size ocean waves enter but have no place to go but swell up into ginormous waves. He warned us to get ready. You enter the narrows calmly but within minutes the waves get inexorably bigger and bigger with the wind picking up even stronger until this 45 footer was angling up and down at +/-30°, every time coming down with a thundering crash and shudder that you thought surely the boat might break apart. Everybody was holding on for dear life to whatever they could find at hand. Then, as gradually as it built up, it eventually calmed back down but all of us were then talking at 90 mph about it as we were all so hyped up on adrenaline.
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Bad. Hight lite between brackets for answer { Sounds like a %&*%% }
Dave
Sorry I am just joking.and that is a bad one
I have had a lot flights that was worrst. Just fun of flying NOT.
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around
Junior Member
Dave,
Currents can vary from 1 to 5 knots in the open ocean. For a large ship travelling at 22 kts this is a small impact compared to say a 150 kt Jet Steam on an aircraft travelling at 450 kts.
The Gulf Steam is normally viewed as the fastest ocean current at 5 kts but is confined to a very narrow band. The Antarctic Circumpolar Current is viewed as the most “powerful” at 2 kts but covering a very wide area, Near shore tidal currents can be much higher but fluctuate widely with time.
Cheers,
Adrian
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History on E6B computer a 1930's miracle.
⸻⸻⸻⸻⸻⸻
The device's original name is E-6B, but is often abbreviated as E6B, or hyphenated as E6-B for commercial purposes.
The E-6B was developed in the United States by Naval Lt. Philip Dalton (1903–1941) in the late 1930s. The name comes from its original part number for the U.S Army Air Corps, before its reorganization in June 1941.
Philip Dalton was a Cornell University graduate who joined the United States Army as an artillery officer, but soon resigned and became a Naval Reserve pilot from 1931 until he died in a plane crash with a student practicing spins. He, with P. V. H. Weems, invented, patented and marketed a series of flight computers.
Dalton's first popular computer was his 1933 Model B, the circular slide rule with true airspeed (TAS) and altitude corrections pilots know so well. In 1936 he put a double-drift diagram on its reverse to create what the U.S. Army Air Corps (USAAC) designated as the E-1, E-1A and E-1B.
A couple of years later he invented the Mark VII, again using his Model B slide rule as a focal point. It was hugely popular with both the military and the airlines. Fred Noonan, Amelia Earhart's navigator on her attempted circling of the globe, used one on their last flight. Dalton felt that it was a rushed design, and wanted to create something more accurate, easier to use, and able to handle higher flight speeds.
Closeup photo of a cardboard E6B
So he came up with his now famous wind arc slide, but printed on an endless cloth belt moved inside a square box by a knob. He applied for a patent in 1936 (granted in 1937 as 2,097,116). This was for the Model C, D and G computers widely used in World War II by the British Commonwealth (as the "Dalton Dead Reckoning Computer"), the U.S. Navy, copied by the Japanese, and improved on by the Germans, through Siegfried Knemeyer's invention of the disc-type Dreieckrechner device, somewhat similar to the eventual E6-B's backside compass rose dial in general appearance, but having the compass rose on the front instead for real-time calculations of the wind triangle at any time while in flight. These are commonly available on collectible auction web sites.
The U.S. Army Air Corps decided the endless belt computer cost too much to manufacture, so later in 1937 Dalton morphed it to a simple, rigid, flat wind slide, with his old Model B circular slide rule included on the reverse. He called this prototype his Model H; the Army called it the E-6A.
In 1938 the Army wrote formal specifications, and had him make a few changes, which Weems called the Model J. The changes included moving the "10" mark to the top instead of the original "60". This "E-6B" was introduced to the Army in 1940, but it took Pearl Harbor for the Army Air Forces (as the former "Army Air Corps" was renamed on June 20, 1941) to place a large order. Over 400,000 E-6Bs were manufactured during World War II, mostly of a plastic that glows under black light (cockpits were illuminated this way at night).
The base name "E-6" was fairly arbitrary, as there were no standards for stock numbering at the time. For example, other USAAC computers of that time were the C-2, D-2, D-4, E-1 and G-1, and flight pants became E-1s as well. Most likely they chose "E" because Dalton's previously combined time and wind computer had been the E-1. The "B" simply meant it was the production model.
The designation "E-6B" was officially marked on the device only for a couple of years. By 1943 the Army and Navy changed the marking to their joint standard, the AN-C-74 (Army/Navy Computer 74). A year or so later it was changed to AN-5835, and then to AN-5834 (1948). The USAF called later updates the MB-4 (1953) and the CPU-26 (1958), but navigators and most instruction manuals continued using the original E-6B name. Many just called it the "Dalton Dead Reckoning Computer", one of its original markings.
Frontside of the military 6B/345
Backside of the military 6B/345
For
more on this visit
https://en.m.wikipedia.org/w/index.php?title=E6B&wprov=rarw1
Dave
⸻⸻⸻⸻⸻⸻
The device's original name is E-6B, but is often abbreviated as E6B, or hyphenated as E6-B for commercial purposes.
The E-6B was developed in the United States by Naval Lt. Philip Dalton (1903–1941) in the late 1930s. The name comes from its original part number for the U.S Army Air Corps, before its reorganization in June 1941.
Philip Dalton was a Cornell University graduate who joined the United States Army as an artillery officer, but soon resigned and became a Naval Reserve pilot from 1931 until he died in a plane crash with a student practicing spins. He, with P. V. H. Weems, invented, patented and marketed a series of flight computers.
Dalton's first popular computer was his 1933 Model B, the circular slide rule with true airspeed (TAS) and altitude corrections pilots know so well. In 1936 he put a double-drift diagram on its reverse to create what the U.S. Army Air Corps (USAAC) designated as the E-1, E-1A and E-1B.
A couple of years later he invented the Mark VII, again using his Model B slide rule as a focal point. It was hugely popular with both the military and the airlines. Fred Noonan, Amelia Earhart's navigator on her attempted circling of the globe, used one on their last flight. Dalton felt that it was a rushed design, and wanted to create something more accurate, easier to use, and able to handle higher flight speeds.
Closeup photo of a cardboard E6BSo he came up with his now famous wind arc slide, but printed on an endless cloth belt moved inside a square box by a knob. He applied for a patent in 1936 (granted in 1937 as 2,097,116). This was for the Model C, D and G computers widely used in World War II by the British Commonwealth (as the "Dalton Dead Reckoning Computer"), the U.S. Navy, copied by the Japanese, and improved on by the Germans, through Siegfried Knemeyer's invention of the disc-type Dreieckrechner device, somewhat similar to the eventual E6-B's backside compass rose dial in general appearance, but having the compass rose on the front instead for real-time calculations of the wind triangle at any time while in flight. These are commonly available on collectible auction web sites.
The U.S. Army Air Corps decided the endless belt computer cost too much to manufacture, so later in 1937 Dalton morphed it to a simple, rigid, flat wind slide, with his old Model B circular slide rule included on the reverse. He called this prototype his Model H; the Army called it the E-6A.
In 1938 the Army wrote formal specifications, and had him make a few changes, which Weems called the Model J. The changes included moving the "10" mark to the top instead of the original "60". This "E-6B" was introduced to the Army in 1940, but it took Pearl Harbor for the Army Air Forces (as the former "Army Air Corps" was renamed on June 20, 1941) to place a large order. Over 400,000 E-6Bs were manufactured during World War II, mostly of a plastic that glows under black light (cockpits were illuminated this way at night).
The base name "E-6" was fairly arbitrary, as there were no standards for stock numbering at the time. For example, other USAAC computers of that time were the C-2, D-2, D-4, E-1 and G-1, and flight pants became E-1s as well. Most likely they chose "E" because Dalton's previously combined time and wind computer had been the E-1. The "B" simply meant it was the production model.
The designation "E-6B" was officially marked on the device only for a couple of years. By 1943 the Army and Navy changed the marking to their joint standard, the AN-C-74 (Army/Navy Computer 74). A year or so later it was changed to AN-5835, and then to AN-5834 (1948). The USAF called later updates the MB-4 (1953) and the CPU-26 (1958), but navigators and most instruction manuals continued using the original E-6B name. Many just called it the "Dalton Dead Reckoning Computer", one of its original markings.
.jpg)
Frontside of the military 6B/345
.jpg)
Backside of the military 6B/345For
https://en.m.wikipedia.org/w/index.php?title=E6B&wprov=rarw1
Dave
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around
Junior Member
Dave,
This was my last at-sea command:
https://en.wikipedia.org/wiki/HMCS_Algonquin_(DDG_283)
Now the primary major surface combatant in the Canadian navy is the Canadian Patrol Frigate:
https://en.wikipedia.org/wiki/Halifax-class_frigate
Cheers,
Adrian
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SmithDoor and Friends,
I was reading an account of the pre-WWII submarines, and came across a description of a device that was also a paper "computer" referred to as an "Is-Was" that was used to project location from known historical sub position data. I think that was replaced by the torpedo-setting mechanical computers and plotters used in WWII. Do you know anything about that?
--ShopShoe
I was reading an account of the pre-WWII submarines, and came across a description of a device that was also a paper "computer" referred to as an "Is-Was" that was used to project location from known historical sub position data. I think that was replaced by the torpedo-setting mechanical computers and plotters used in WWII. Do you know anything about that?
--ShopShoe
What little I know is they take submarines to Panama Canal
Cut a hole in the sub and place inside the submarines.
It used cams and gears and did good job of hitting the other sides ships.
The Airforce on the B29 had tub type for bombing. Used 37 tubes. I do not any else.
{The tubes at time could have multiple grids in side. This is like having 3 or 4 transistors in a tube and is analog.
To convert from analog to digital takes a lot of transistors.
Today it takes a IC chip to do same job. }.
It is amazing what did back in ww2.
Dave
Here is a working sliderule on the internet.
This my drafting sliderule. Note leather case at top
Closeup in Black & White⁰ for better view
https://sliderulemuseum.com/VirtualSR2/react/hemmi_versalog_ii.html
This my drafting sliderule. Note leather case at top
Closeup in Black & White⁰ for better view
https://sliderulemuseum.com/VirtualSR2/react/hemmi_versalog_ii.html
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Here a online similar for E6B that goes to the Navy speeds too.Dave,
Currents can vary from 1 to 5 knots in the open ocean. For a large ship travelling at 22 kts this is a small impact compared to say a 150 kt Jet Steam on an aircraft travelling at 450 kts.
The Gulf Steam is normally viewed as the fastest ocean current at 5 kts but is confined to a very narrow band. The Antarctic Circumpolar Current is viewed as the most “powerful” at 2 kts but covering a very wide area, Near shore tidal currents can be much higher but fluctuate widely with time.
Cheers,
Adrian
Works great you see what current will do to a ship.
Remember current speed directions use wind speed and direction
https://e6bx.com/e6b-simulator/
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