Loss of separation at Dublin last March

cml387

The AAIU have issued their report on an incident at DUB last March when an arriving and departing aircraft came close enough to require a serious incident report.

The nub of the issue was that the departing aircraft had not received cabin secure as they approached 28 threshold, whereas the controller understood they were actually ready for immediate departure.

There was a similar incident recently (not mentioned in the report) of a BA plane not entirely ready for departure when at the holding point which we all remember.

Maybe an additional argument for a second runway, given the tight margins that are in operation at busy times.

Mantis Toboggan

Am I right in saying that the planes were over 800 metres apart? If so, that's almost a kilometre, I don't see the issue.

EchoIndia

Where things could have become tricky is if the arriving aircraft had had to make a go-around with the departing one just becoming airborne, or indeed if the departure had had to abort takeoff. The normal margins allow potential conflicts in these situations to be handled safely. In this case these were eroded somewhat.

One thing that strikes me is that, many years ago, the term "affirmative" was replaced with "affirm", specifically to reduce the likelihood of a clipped transmission being confused as between "affirmative" and "negative". The Luton-bound aircraft, when taxiing out, used the correct term. Subsequently, the controller appears to have misheard an indistinct "negative" but treated it as "affirmative", which is not the term he/she should have been expecting to hear.