Virtual Planes, Virtual Airports: Inside the World of VATSIM
rockpapershotgun.com
rockpapershotgun.com
Why isn't this information transmitted digitally? Fire it off in a sideband of the radio transmission, or even just as a half-second modem bleep in the audio track. You keep the voice communication for redundancy and backwards compatibility for planes that don't have the equipment, but having the information actually appear on your console is surely highly desirable?
...actually, isn't this technology already available, so that ATC can give commands to planes flying on full autopilot?
Are you _absolutely_ certain you can prevent unauthorized use of this channel? Keep in mind what you're proposing is that hundreds of semi-independent agencies have the ability to push this information directly into the aircraft FMC.
The other reason it's communicated this way is because over an open audio channel other pilots can listen to the traffic and keep themselves apprised of situations in the local airspace and advise of conflicts with previous instructions.
Finally, it leaves the choice in the hands of the pilot. The controller may give incompatible instructions (runway not long enough for landing weight) or make impossible guidance requests (airspeed too low for landing configuration). The FMC is not a friendly computer system to use and it is highly integrated with most of the critical flight systems. It most certainly isn't perfect and pilots absolutely do not want anyone to be able to make changes to their flight data remotely.
> ...actually, isn't this technology already available, so that ATC can give commands to planes flying on full autopilot?
Nope. No one is particularly interested in developing it either.
Er, no, that's not what I'm proposing.
I'm proposing a way to get the six pieces of complex information from the ATC onto a display which the pilot can read, to avoid the pilot having to remember/write down those six pieces of information in a potentially information-dense situation. I would have this in addition to the existing voice control as a backup. The pilot still does the flying.
Cockpits are pretty busy places.. it would be difficult for a pilot to verify that the information on the display is _still_ consistent with the last audio update from a controller. Or, they may miss the fact that they got a radio call to change their speed, but the display did not get updated and still shows the old requested speed. Or, perhaps a rogue or unintended signal was interpreted by the unit and the data updated with incorrect (and dangerous) values.
As it is, the radio communications can impose extra load, but this is usually the responsibility of the non-flying pilot and it occurs during routine and non-complicated portions of the flight. For a large segment of the flight path, these updates will simply involve changing a setting on the auto pilot console (change of heading or airspeed). Your landing runway is assigned and confirmed by approach control _before_ you actually speak to the tower and usually before you even have the airport in sight. In smaller airports this responsibility _may_ be handled by the same person or by the larger ATC center serving that area, but the information is handed out early and in specific phases to help reduce the load on the flight crew.
The call and response system is highly portable and useful and is typically quite resistant to "human factors" errors, when you start adding automation and new devices to the cockpit that can devolve into emergent behavior you start to see "human factors" errors occur.
Huh? Roger and Wilco are said all the time in real life (obviously not an appropriate response to all ATC requests, but far from forbidden).
Having thought about it some more, the statement about "roger" not being allowed was probably missing some context. He probably meant it in the context of an ATC instruction that requires reading back.
The pilots taking the time to go through VATSIM are also the ones taking the time to do things right. They almost always finish their trips. When they don't, they usually let the controllers know.