Naked Science Forum
General Discussion & Feedback => Just Chat! => Topic started by: NTYNUT on 16/08/2018 14:09:47
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Hello
What is ADS-B and MLAT
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ADS-B is a way of planes broadcasting their location so that ground-based air-traffic controllers can coordinate the planes, and so that planes can detect nearby planes. This has greatly improved the safety of air transport.
It depends on the plane accurately knowing its location and velocity, eg from a satellite-based GPS system.
See: https://en.wikipedia.org/wiki/Traffic_collision_avoidance_system#Relationship_to_automatic_dependent_surveillance-broadcast_(ADS-B)
If you want to know a lot more about it, listen (2 hours): http://omegataupodcast.net/266-secondary-surveillance-radar/
Multilateration (MLAT) is a much older form of navigation (before GPS), where a plane measured its location by timing signals from ground stations. It was used in the days before computers, so the human navigator had to do a number of complex calculations.
See: https://en.wikipedia.org/wiki/Multilateration
Today, the complex GPS navigation calculations are hidden from us by the computer in our smartphones.
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ADS-B is a way of planes broadcasting their location so that ground-based air-traffic controllers can coordinate the planes, and so that planes can detect nearby planes.
Hello
how does Air-traffic controllers control plane what they talk
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how does Air-traffic controllers control plane what they talk
Air Traffic Control radar prompts the plane to transmit an identifying signal.
Each Air Traffic Controller is allocated a region of airspace to monitor; they can see each plane's identity, location and track on a radar screen. The Air Traffic Controller can communicate with the planes via radio, and give instructions that ensure safe spacing between aircraft - ensuring both horizontal and vertical separation.
Large airports have a control tower, which directs aircraft moving on the ground, and also approaching and leaving the airport. The airport control tower can redirect aircraft to different runways if weather conditions change, or if there is an emergency situation. Controllers ensure that small planes don't pass near the invisible vortex left behind by large aircraft, as this can cause severe turbulence for small planes.
Very small airports may have a control tower that is manned only at certain hours, or it may just be a landing strip with no control tower. In this case, pilots communicate directly with each other via radio to ensure they don't collide.
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Air Traffic Control radar prompts the plane to transmit an identifying signal.
Each Air Traffic Controller is allocated a region of airspace to monitor; they can see each plane's identity, location and track on a radar screen. The Air Traffic Controller can communicate with the planes via radio, and give instructions that ensure safe spacing between aircraft - ensuring both horizontal and vertical separation.
Hello
There are nearly 35,000 plane in sky how to talk with them which technology is used for doing this
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There are nearly 35,000 plane in sky how to talk with them which technology is used for doing this
Airport radar uses a rotating dish which directs a narrow signal, interrogating only the planes in a small part of the sky.
- The radar signals travel in straight lines, so it won't receive responses from planes which are over the horizon. That removes most of the 35,000 planes around the world
- If two planes are close together in the sky, as the radar rotates, one will still be in the beam, and the other will be out of the beam. Then signals can be received from the other. So both can be uniquely identified, even if they are close together in the sky.
- Airport radar also uses a signal broadcast from the rear of the dish which suppresses responses from planes in other parts of the sky
There are standard frequencies for aviation communication.
-Short-range communication uses VHF frequencies which travels in straight lines, so it does not affect planes over the horizon. But I understand that each airport has its own frequency for incoming traffic, and air traffic control can ask pilots to change to different frequencies so that different controllers can communicate with a separate group of airplanes.
- Long distance communication uses High-Frequency radio, which has longer range; this would not be used in areas close to cities
- I imagine that planes will increasingly use satellite communication, as this is becoming more reliable than High-Frequency radio, and able to provide better data on weather and turbulence, including providing weather data that can be used by other planes flying in the area, and the location of other planes in the area.
English has been defined as the standard language for international aircraft and international airports.
See: https://en.wikipedia.org/wiki/Aviation_communication#Aviation_English
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Hello
That mean English is used to talk with pilot and how plane is started with battery
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That mean English is used to talk with pilot
Yes, English is used for international flights.
A local language may be used for local flights.
how is a plane started with a battery?
Small aeroplanes, used on small airports can have a starter motor, like a motor car.
Large jet planes, flying out of large airports typically connect to a power supply on the ground while they are at the terminal.
- This power can be used to start the Auxiliary Power Unit (APU)
- The APU can be used to start the other engines
Military aircraft often use an air start: https://en.wikipedia.org/wiki/Air-start_system#Gas_turbines
In emergency situations, where an aircraft loses power while it is at cruising altitude, the airplane can use its height, go into a dive, providing airflow that restarts the engines.
But @alancalverd knows a lot more about planes than I do...
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hello
how to get new passenger aeroplane in india
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