I would have thought that anything on the decscent path, at, near, or past the threshhold should not expect another aircraft to be crossing the runway. Fair enough 4NM away, but this looked like the landing aircraft was much closer. And as a passenger I share Cobalt’s sentiment. Surely operating capacity isnt such that this kind of close call is happening all the time.
I haven’t flown much in Spain, and the bit I did was a good few years ago. But at that time, I wasn’t left with a positive impression of ATC there.
The feeling that I got was that they weren’t comfortable conversing in English, and as a result they would prefer to let a situation develop and become close if they thought it would all work out ok, rather than have to intervene by speaking English. Of course this was only a feeling that I got from what I saw and experienced.
This looks only reinforces that opinion. It looks like the controller was aware of what was happening, and decided to let it happen as they figured it would work out, even if it was tight.
What would happen if it was IMC and the landing aircraft was on autoland?
The A340 would disturb the ILS signal upon entering the sensitive area, the B767’s autopilot would kick off and the crew would fly a missed approach.
The A340 would disturb the ILS signal upon entering the sensitive area, the B767’s autopilot would kick off
Would you rely on that absolutely?
I know the ILS signal is monitored for integrity but obviously it isn’t monitored from a point located on the approach path.
I know the ILS signal is monitored for integrity but obviously it isn’t monitored from a point located on the approach path.
It’s likely not the ground monitoring stations signalling a problem, but the onboard ILS receiver sanity checks. Hopefully every Cat > I approved ILS receiver has a better “flag circuit” than the KN72, i.e. signals a problem if one of the tones modulation depth falls out of spec or maybe even if the rate of change is above a certain threshold. Whether the approaching aircraft actually sees an ILS signal anomaly likely depends on the airport layout, I’d expect a big lump of metal crossing close to the threshold not to disturb the localizer signal path (the localizer antennae being placed behind the runway, the line of sight should pass well above the crossing lump of metal) or the glideslope (the lump of metal behind the glideslope antennae, there’s probably only some back scattering) enough for the onboard electronics to detect a problem.
