The greatest story of dead reckoning is Ernest Shackleton crossing 800 miles of the Southern Ocean in seas so rough they were only able to take 4 sightings of the sun!!

 

 

Polar explorers back then were tough S.O.B.s! I've read Shackleton's book South several times, and I'm amazed at what they endured. There was an excellent TV movie a few years back starring Kenneth Branaugh as Shackleton.

 

William Bligh's 3,600 nautical mile journey on an open boat was a pretty amazing feat of navigation and survival too.

Holy smokes thanks folks...I am going to have to go home and absorb all this new info.

 

Oh, and I really want a vintage sextant for next christmas

As indicated, there have been a small number of sextants for FS over the years, interesting to try once, but seriously a moving map with GPS is so much easier! :LMAO:

 

By the way, "dead" reckoning is not dead at all, but rather "ded." as in deduced reckoning. It also helps a lot to know prevailing winds when using this method.

 

Best regards.

Luis

Actually, how do they do it now?!?! VOR is line of site, the world is round, and the oceans are....well they are oceans, and not littered with VOR buoys....or are they?

 

In the olden days, airliners & bombers carried along a navigator. The navigator poured all over the charts with rulers, pencils, and possibly headphones for an old style radio wave, and then told the pilot which direction to fly. Today's GPS can tell the pilot which direction to go...........and get them to the proper location within three feet. It can also give a correct altitude within 10-30 feet. Since GPS uses two dozen satellites in orbit, it doesn't have problems with line of sight. The GPS will pick up eight to twelve satellites, and use the best signals. It only needs three or four. The newest up to date airliners use GPS as the number one navigation system. It updates the inertial nav system, instead of the older VOR/DME method, which would do the updates while the plane taxied at the airport.

The "LONE EAGLE" Charles Lindberg could have show and explain it..No radios!!...DEAD RECKONING...reckon Correctly,or yer dead....Yes ,A compass,a chart ,and a time piece!...As you know a Compass has many peculiarity's like Deviation,variation,dip errors,Northerly turning error,Acceleration error....Factor in the wind DIRECTION,WIND SPEED,..weather,Controlling the plane....its a Task! with out room for error!..THE e6b or simply the "whiz wheel", FLIGHT COMPUTER HELPS A LOT......The same for early explorers in sailing ships!....Stars ,if you can see them are an other way to find yer way!...Over the vast seas ..looking at the direction of the swells...can help...Of course yer eyes are the most important..Out of the Cockpit!..Over land ,towns had some Rooftops with their name....Road charts helped greatly,The IRON RAILS most helpful..Rivers,Roads,as all topography.is!....Binoculars and Good Sunglasses are a must!!

 

...http://www.centennialofflight.gov/essay/Government_Role/navigation/POL13.htm..

By the way, "dead" reckoning is not dead at all, but rather "ded." as in deduced reckoning.

 

This is one argument folks use who support the idea that dead reckoning is actually "ded reckoning".

 

This is certainly one of those things debated in aviation. My purpose here is not to argue which is "correct"... just to introduce an article where the writer seems to have done some legitimate research into the origin of the term.

 

One thing you might be interested in knowing, as pointed out in the article, you will not find the FAA (or Coast Guard) using the term "ded" or "ded.". It's termed as "dead reckoning". :Nerd:

 

Btw... just as Fr. Bill's tagline says, “People don’t need an important issue to fight about. They’ll take anything available and inflate it to the size they need.” ... so I thought I would do that here. :Just Kidding:

 

Here's that article mentioned above: Is "dead reckoning" short for "deduced reckoning"? http://www.straightd...duced-reckoning Enjoy!

 

btw Luis... :drinks:

:Peace: :drinks:

 

Best regards.

Luis

I go with "dead" simply because "deduced reckoning" is redundant. It's like thoughtful thinking.

 

Plus, as noted, that's the way official entities I am familiar with such as the FAA, US Navy, etc. spell it.

 

Personally, I believe "dead" refers to precision, such as "dead on target" or "dead accurate", not life & death.

I go with "dead" simply because "deduced reckoning" is redundant. It's like thoughtful thinking.

 

 

A. I ordered Markinson to have Santiago transferred off the base immediately.

 

Q. Why?

 

A. I felt that his life might be in danger once word of the letter got out.

 

Q. Grave danger?

 

A. Is there another kind?

 

(Exchange between Lt. Daniel Kaffee and Col. Nathan Jessup in "A Few Good Men".)

Corrupt politician.

In the olden days, airliners & bombers carried along a navigator. The navigator poured all over the charts with rulers, pencils, and possibly headphones for an old style radio wave, and then told the pilot which direction to fly. Today's GPS can tell the pilot which direction to go...........and get them to the proper location within three feet. It can also give a correct altitude within 10-30 feet. Since GPS uses two dozen satellites in orbit, it doesn't have problems with line of sight. The GPS will pick up eight to twelve satellites, and use the best signals. It only needs three or four. The newest up to date airliners use GPS as the number one navigation system. It updates the inertial nav system, instead of the older VOR/DME method, which would do the updates while the plane taxied at the airport.

 

In principle you need at least 4 satellites. When solving the equations that determine your position there are four unknowns: your three spatial coordinates (X,Y,Z, or lat, lon and alt) and the error in the clock in your GPS receiver. Since you have four unknowns you need to know the distance to four satellites to solve for all four. With a sufficiently accurate clock you might be able to dispense with the fourth satellite.

 

Extra satelittes make your measurements more precise and can help compensate for small sources of error (e.g. moisture in the atmosphere).