Air Traffic Control Separation Standards

It's been a frustrating couple of weeks. A few things have come up, but one thing in particular got under my skin a bit.

You may or may not have read my previous post on a runway standard issue that came up, but another issue with the same standard has come up again. Here's the scenario.

ABC was cleared to land and roughly 500m down the runway.

There had obviously been a bit of confusion in the cockpit as to whether DEF was to be for a touch and go or a full stop. Previous to this point in time he had called on base for a touch and go. The clearance was withheld as ABC was still on short final and DEF was advised he was number two.

DEF then made a second call on about a 1 mile final that he was to be for a full stop landing. My assessment was that ABC would shortly vacate, even if he required full length for his landing roll there was no collision risk. So DEF was then cleared to land.

ABC vacated at the second taxiway, DEF landed shortly behind and that's the end of the story.


ABC contacted the ground controller and advised him that DEF had been given a landing clearance while he was still on the runway. The ground controller then advised the pilot that no separation standard had been breached, as a landing clearance can be issued with another aircraft on the runway provided that in the opinion of the controller no collision risks exists, end of story.


Not happy with the ground controllers response the pilot of ABC then attempted to convince the ground controller otherwise. He then proceeded to tell how he had to brake hard to vacate the runway at the taxiway he did, otherwise he would have required full length. The standard was then further explained to the pilot which was then responded to with silence.

An easy way to avoid this type of confusion is for me as the controller to avoid using the standard. It was quite easy to withhold the clearance until ABC had vacated and prior to DEF second call on final that is probably what would have happened. But in my opinion I had good reason to use the standard.

The first reason is because it is a standard that can be used. It's an open and shut case really and there's not much more to comment on that.

The second reason in this scenario is to cut down transmissions. Saving time is a good habit to get into in this job as things can get out of hand if you don't. We are trained in various techniques to do this and reducing the amount of transmissions is one of them. It reduces workload and reduces frequency congestion. How many pilots reading this have been in a control zone and had to "wait in line" for an opportunity to make a transmission? I'd say all of you. By reducing the transmissions the controller makes it also reduces the number of transmissions the pilot makes and things run a hell of a lot smoother.

In my explanations of scenarios I only ever include the aircraft involved. At the time this situation happened I had at least half a dozen other aircraft on frequency and other traffic conflictions to consider. When DEF called on final for a full stop landing by issuing the clearance then, I reduced the frequency transmissions by two and was then also able to transmit to another aircraft.

As previously explained, the Air Traffic Controller's course included a lot of theory from the private pilot's license course and we have publications readily available in the tower, used by pilots such as AIP. Maybe there should be a topic on ATC Separation Standards in the course for a PPL? If not maybe some documentation available on this topic?

To my knowledge there is no such thing but maybe one day someone might clue on to the fact that it's a good idea.

Until then...