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Fly On Track Radar Replay #3
London TMA (Over Sussex)

You can view a real radar replay of an infringement here if you have Windows Media player.... but before you do, read the following to understand what you are seeing.... a classic example of what can happen when G.A. pilots make what they may think is a fairly minor infringement into controlled airspace - in this case by descending too late to avoid a lower block of the TMA ahead. The incident this month may seem less dramatic than previous ones, but as the intentions of the 'unknown' infringing aircraft are not known, a commercial inbound to Gatwick has to be stopped in its descent within the LTMA and resequenced - delay for the passengers, money for the airline, more fuel burned.

Very soon after the playback starts, the IFR traffic that has to be broken off will be briefly highlighted for you with a blue label - it's squawking 1067. Below the Squawk is the 'KK' to show the aircraft is inbound to Gatwick (EGKK) and to the left of the 'KK' is the altitude/flight level. In this case the green figure (initially '093') shows the current level FL093 and you will see it descend below FL080. At an early stage you may see a radar track heading South near the IFR traffic, but ignore it, this is very high level traffic way above and the 'squawk detail' has been removed so not to obscure the one we are interested in. A few seconds into the replay, you will see a '7000' squawk heading North East, briefly highlighted for you in RED, and you will see the pilot is at 3000' from the the 030 and there is no problem, as the base of controlled airspace is at 3500' here, as will soon be shown on the replay.

The '7000' should commence a descent to be under 2500' by the time it reaches the base of controlled airspace at that altitude ahead. No descent is made by the infringer, so the aircraft enters the LTMA (Class A) without a clearance, as 'unknown traffic'. When such a thing happens, the controllers have to turn any known traffic within 5 miles and 5000' away from the infringer, whose intentions, aircraft type, climb speeds, etc etc are unknown. In this case the IFR traffic in the descent has to be turned away for resequencing once it it obvious that it is getting within 5000' and 5 miles of the '7000' infringer. Shortly after the IFR has been turned away, the '7000' pilot finally decides to descend below 2500' and out of controlled airspace. The pilot was not followed up, and therefore the pilot's thoughts and reasons are not recorded, but presumably he/she never realised the delay and costs caused by this short incursion. Short incusions can and do 'matter'!

Click on the image on the left to launch the radar clip. It is currently only available in 'wmv' format, therefore Windows Media Player should be used. Many thanks to all at NATS who have gone out of their way to make the public viewing of this clip possible. A different infringement and analysis will appear every few weeks - until they stop!

The latest radar replay (#7) shows an aircraft starting in the Manchester Low Level Corridor then infringing the CTR with the controllers breaking off approaches ahead of it.

The latest radar replay (#6) shows a small aircraft slowly transiting Stansted CTR.

Radar replay (#5) shows an aircraft not noticing the lowered airspace ahead near Compton VOR and breaking in at altitude.

Radar replay (#4) shows a student lost and crossing the Luton CTR and extended runway centre line.

This radar replay (#3) shows disruption caused by a short infringement into a layer of the LTMA over Sussex, eventually descending to the correct altitude but not early enough.

This radar replay (#2) shows a problem caused by a pilot NOT squawking Mode C and then getting lost eventually turning up close to the extended centreline of Stansted in the CTA. Due to the lack of Mode C the controller didn't know he was in the CTA.

The original radar replay (#1) shows the disruption caused when a pilot makes a navigation mistake and enters the Heathrow CTR and heads down towards final approach without realising it (at first!)