Airprox

[casper]

I always thought that when two aircraft came into close proximity to each other it was called a 'near miss' - this may be the case but I've just learnt that there's also something called 'Airprox'

An Airprox is a situation in which, in the opinion of a pilot or a controller, the distance between aircraft as well as their relative positions and speed have been such that the safety of the aircraft involved was or may have been compromised.

I've also found out that there were 3 of these reported over Northern Ireland

During the period from 1 June 2006 to 31 May 2007, three Airprox incidents in airspace over Northern Ireland were reported to the independent UK Airprox Board (UKAB) for investigation and assessment.

One of these Airprox is reported to have involved one aircraft operating into Belfast International airport, the other aircraft being outbound from Belfast City airport. This Airprox remains subject to assessment by the UKAB following which the findings will be published both on the UKAB's website at www.airproxboard.org.uk and subsequently in hardcopy.

[Scuzi]

That's right. We have two different types of "near miss". An Airprox report is filed usually when aircraft become REALLY close to one another, i.e the risk of collision was very high. In ATC we also have what is called a "LOS" or "Loss of Separation". An Airprox falls under this category but a Loss of separation can be less serious. For example, in the London TMA we are permitted to use 3 miles horizontal separation between two aircraft at the same level. If an error of judgement or a mistake on the pilot's part resulted in the horizontal seapration becoming less than 3 miles or less than 1000ft vertical, this would be deemed a LOS. They might be perfectly safe flying at 2.5 miles apart with no track confliction and no risk of collision but because it is less than permitted it has to be reported an investigated.

[casper]

Hi Scuzi long time no hear Many thanks for the info. So how are things in ATC?

[Scuzi]

Aye it's been a while! Things are good in the world of ATC at the minute. It's nice and quiet due to the winter schedules which means plenty of breaks and time off:) How're you these days?