Light aircraft inside airport zones

[j2wo]

Hi,

This is probably easily explained, but I'm curious so I will ask here - not brave enough to stick this on ATC! :}

Yesterday, 5th May, around 1420, I saw a light aircraft very low, under 500ft fly straight across the ILS approach for Gatwick. This was on the 26L end just next to the railway line. Surely this isn't allowed by ATC, the aircraft being so low, simply flying right across?

I was surprised that the aircraft was allowed to do this as he passed over the final ILS lights/glidescope before the actual threshold.

Anyone know if this is usual practice, I was surprised to see it pass so close to the airport, especially crossing right through departing traffic!

Thanks in advance.

[jabberwok]

Cutting out the technicalities there is no problem with light aircraft flying in controlled airspace as long as they are talking to ATC.

[BOAC]

not brave enough to stick this on ATC! - no chance! They'll track you down here:)

I'm a little confused by your 'geometry' as you refer to crossing the 26 ILS approach but "crossing right through departing traffic!" - if you mean traffic was taking off westerly (on 26) then subject to ATC approval, of course, that is the best place to cross - ie behind departing traffic, and there would not be anyone on the ILS that close in with a departure in progress (not even at Gastwick:p ).

[NudgingSteel]

j2wo,
Hello and don't worry, nothing sinister happening from the sounds of it (assuming the light aircraft had been cleared through the zone by Gatwick ATC that is!!!!)
As a controller, if a light aircraft wants to cross the approach or climbout, the easiest place for me to separate it from other traffic is at or near the runway. Firstly, it's easier for me to see and assess when it's crossed the runway or the final approach track.
Secondly, by crossing close to the runway, the light aircraft will almost certainly be well above the flight path of arriving or departing traffic, and therefore isn't affected by vortex wake [the turbulence generated behind all aeroplanes; the bigger the aircraft then the worse the turbulence behind it]. If it were to cross the approach or climbout at a similar level to a heavy jet, the vortex spacing requirement can be up to 8 miles (or 4 minutes). You can appreciate this isn't an option if the commercial jets are piling down final approach every 4 - 6 miles!!!!

[No comment]

Also, very stupid of me if I'm wrong but isn't there a small grass strip over at Vallance byways? I've seen a light aircraft buzz over the North Terminal and drop down behind the fire dump before now.

I was at work so couldn't watch it too closely so might be wrong!

[Cahlibahn]

Future737NG_PIC

The bi-plane you saw is based at Rush Green which is in the Luton zone. There is an agreement with Luton and he would have been talking to Luton Radar. If it was an unauthorised incursion there is every liklihood he would have been traced. I can't post URLs here (I don't think) but you might be interested to Google 'flyontrack'.