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Flight 4U 9525

Discussion in 'General Discussion' started by securespark, 26 Mar 2015.

  1. EFLImpudence

    EFLImpudence

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    There was talk on the radio today that pilots are not really necessary any more but people feel safer with a person in charge.

    The feeling is that if anything went wrong with the system the pilot could take over.
    However, it was said, in most cases of something going wrong it was the pilot at fault.

    I must say I am not too keen on driverless cars but then...
     
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  3. Brigadier

    Brigadier

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    "Although four satellites are required for normal operation, fewer apply in special cases. If one variable is already known, a receiver can determine its position using only three satellites. For example, a ship or aircraft may have known elevation."

    Source: Wikipedia - Global Positioning Systems.
     
  4. so what? just basic trigonometry.
     
  5. wotan

    wotan

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    Sealed instructions to two cabin crew, that have to be initiated from different locations within the aircraft simultaneously, same codes never issued twice?

    Wotan
     
  6. JBR

    JBR

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    ]

    Terrorists on board the aircraft would be able to easily obtain these instructions and so gain access to the flight deck.
     
  7. Mikefromlondon

    Mikefromlondon

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    Talking of driverless cars, years ago I used to commute to work 25 miles each way on M11, and the journey was most boring and so routine, and predictable, I used to have a job keeping myself alert, I actually found the slower you drive the more slower your reactions and anticipation times are, and the faster you drive the more alert and faster your reactions are.


    I thought if you had a car that followed white line using a simple photo sensor and a small radar gun in the front to detect another car or truck or any other obstruction, with today's technology and computer software, a digital camera can provide suitable data to act on, ahead, and as well as record steering movement data and synchronise this at the beginning of the motorway journey, you could virtually drive that car hands free and have alarm that sets off if an inadvertent obstruction is detected, so that driver could take over immediately if necessary, and change lane if it is clear to do so otherwise the car would come to halt automatically. This was intended only for motorway runs only and not in built up areas where there are far greater number of obstructions, diversions, and other prohibitions in force from time to time, then you have pedestrians, cyclist, I know google is trialing such cars now.
     
  8. wotan

    wotan

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    They would have to know about it first, and who was carrying the codes.

    Wotan
     
  9. Mikefromlondon

    Mikefromlondon

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    I have never understood why they have life jackets in Air planes instead of parachutes :confused: Defies logic, and you don't see parachutes in ships and boats do you? :mad:
     
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  11. Micilin

    Micilin

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    They slow your descent to the seabed when the plane lands in the ocean.
     
  12. empip

    empip

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    Stick a good old 'Elsan' in cockpit - build it into the seat !!

    [​IMG]

    -0-
     
  13. Brigadier

    Brigadier

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    So, it works in 3D then.
     
  14. Brigadier

    Brigadier

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    Do you think that GPS "knows" that you are in Acacia Avenue, for instance?

    Of course it doesn't.

    A "flock" of in-sight satellites continually broadcast their position and time; your receiver picks up the information from a minimum of four satellites, does some maths, and works out its "exact" position in space (which mostly happens to be on a road, somewhere on the Earth's surface).
    The receiver then matches that location to the map in its memory, and tells you which road you are on.

    Key point being (provided that your receiver can "see" at least four satellites), it knows exactly where you are. But it can't tell you your location or altitude, without a map to compare that position against. Which is why your UK maps-only TomTom is useless in France.
     
  15. of course not, but the raw data from triangulation can tell you your longitude and latitude, but I can't see how triangulation can give you your altitude.
     
  16. Brigadier

    Brigadier

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    They're all just distances from each satellite.
     
  17. of this i am aware. from the garmin site "GPS heights are based on an ellipsoid (a mathematical representation of the earth's shape), while USGS map elevations are based on a vertical datum tied to the geoid (or what is commonly called mean sea level). Basically, they are two different systems, although they have a relationship that has been modeled.

    The main source of error has to do with the arrangement of the satellite configurations during fix determinations. The earth blocks out satellites needed to get a good quality vertical measurement. Once the vertical datum is taken into account, the accuracy permitted by geometry considerations remains less than that of horizontal positions. It is not uncommon for satellite heights to be off from map elevations by +/- 400 ft. Use these values with caution when navigating."
     
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