Late landing clearance
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To come back to this, I am still a bit puzzled why the ATCO needs to drag out the landing clearance.
From above, I understand it's to prevent another aircraft transmitting. But I don't see why this is a problem?
Surely, if you say 'Speedbird 123, cleared to land on runway 24, surface wind is calm', that's sufficient?
Is it because the pilot must also read back the clearance before touch-down and you don't want anyone else getting in the way before he does so?
Equally, I guess savvy pilots must realise when an ATCO is dragging out a clearance and would avoid interrupting it accordingly?
From above, I understand it's to prevent another aircraft transmitting. But I don't see why this is a problem?
Surely, if you say 'Speedbird 123, cleared to land on runway 24, surface wind is calm', that's sufficient?
Is it because the pilot must also read back the clearance before touch-down and you don't want anyone else getting in the way before he does so?
Equally, I guess savvy pilots must realise when an ATCO is dragging out a clearance and would avoid interrupting it accordingly?
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N49 - as explained, if another a/c transmits in a gap, the incoming aircraft may NOT hear the clearance to land in which case it should normally go-around. Nobody wants this, so the controller 'keeps control' of the frequency by keeping it 'open'. Yes. again normally the clearance is read back but if it is so late that the wheels are almost touching...................
- is not this whole thread about the situation where the clearance to land CANNOT be given like that at the 'usual' time as the runway may still be 'occupied', so it is delayed?
Surely, if you say 'Speedbird 123, cleared to land on runway 24, surface wind is calm', that's sufficient?
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BOAC - I know. I understand why it's dragged out, just not so sure about the circumstances leading up to the need to do so. I'm probably missing something fundamental about how the whole process works.
What I was driving at is that if you're going to give a late clearance, I would have thought it would need to be quick. I do see the point about keeping control of the frequency, however.
Anyway, happy to leave it there.
Nick
What I was driving at is that if you're going to give a late clearance, I would have thought it would need to be quick. I do see the point about keeping control of the frequency, however.
Anyway, happy to leave it there.
Nick
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I think you're missing a basic point Nick.
Landing clearance can not be given if an aircraft (or veichle) is occupying the runway. That means that the preceeding aircraft must completely have left the runway area before the next is cleared to land.
In a late landing clearance situation (like in the video) the preceeding is late off the runway, this means the controller has to hold the clearance until the runway is free.
Since only one person can transmit at once (we'll leave technical details out for now I think) the controller needs to make sure nobody else is transmitting when he needs to give landing clearance.
This means that when the preceeding is close to vacating the controller will start his transmission and then drag it out, so he can give the clearance the second the runway is free. That is the reason you may hear things like
" [speaking slowly] callsign, surface wind is calm, runway 23 Right, you are [normal speed] cleared to land"
This means that the aircraft gets it's clearance as soon as possible while making sure nobody else transmits at the critical moment thereby forcing the go around (causing delay, unnessecary noise and also burning fule).
So the reason for the slow transmission is the fact that they are waiting until they may acctually give the clearance and to make sure that nobody prevents them from giving clearance to land.
Did that wall of text do anything?
Landing clearance can not be given if an aircraft (or veichle) is occupying the runway. That means that the preceeding aircraft must completely have left the runway area before the next is cleared to land.
In a late landing clearance situation (like in the video) the preceeding is late off the runway, this means the controller has to hold the clearance until the runway is free.
Since only one person can transmit at once (we'll leave technical details out for now I think) the controller needs to make sure nobody else is transmitting when he needs to give landing clearance.
This means that when the preceeding is close to vacating the controller will start his transmission and then drag it out, so he can give the clearance the second the runway is free. That is the reason you may hear things like
" [speaking slowly] callsign, surface wind is calm, runway 23 Right, you are [normal speed] cleared to land"
This means that the aircraft gets it's clearance as soon as possible while making sure nobody else transmits at the critical moment thereby forcing the go around (causing delay, unnessecary noise and also burning fule).
So the reason for the slow transmission is the fact that they are waiting until they may acctually give the clearance and to make sure that nobody prevents them from giving clearance to land.
Did that wall of text do anything?
I have noticed that "expect late landing clearance" (I've never had one myself) typically goes along with a departure right ahead of you (and thus is preceded with you hearing them getting an "are you ready for immediate departure"), to guard against the inbound deciding to overshoot, the departure hanging about for a few seconds before rolling, and the poor controller then getting into a separation issue.
