Air India B788 descends to 200 ft over water at HKG
https://www.flightglobal.com/news/ar...erfere-454525/
Topical......ATC will not protect the ILS signals if it's CAT 1 approaches in use.....buyer beware.
Topical......ATC will not protect the ILS signals if it's CAT 1 approaches in use.....buyer beware.
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A 747 tail taxiing through the glideslope is different from an airplane taking off going through the localizer beam.
The glideslope disturbance is much closer to the antenna so will be a lot stronger.
Also you need to differentiate between the sensitive and critical areas. Or whatever the nomenclature is.
With the 747 in the glideslope the ILS is basically unusable.
With the aircraft taking off crossing the localizer beam the disturbance should be short and less severe.
(So the real important areas were still protected in Munich while that was not the case in HKG
Just wanted to point out the difference)
Anyway while we are on the topic i'll add another incident:
My guess would be that the 747 Air China Cargo that had a runway excursion / go-around at Chicago O'Hare was the same situation as Munich.
(Incident: China Airlines B744 at Chicago on Jun 21st 2018, veered off the runway and went around)
The glideslope disturbance is much closer to the antenna so will be a lot stronger.
Also you need to differentiate between the sensitive and critical areas. Or whatever the nomenclature is.
With the 747 in the glideslope the ILS is basically unusable.
With the aircraft taking off crossing the localizer beam the disturbance should be short and less severe.
(So the real important areas were still protected in Munich while that was not the case in HKG
Just wanted to point out the difference)
Anyway while we are on the topic i'll add another incident:
My guess would be that the 747 Air China Cargo that had a runway excursion / go-around at Chicago O'Hare was the same situation as Munich.
(Incident: China Airlines B744 at Chicago on Jun 21st 2018, veered off the runway and went around)
Last edited by wiedehopf; 21st Dec 2018 at 12:31.
Only half a speed-brake
Due to the TWY - GS antenna configuration the same was an issue at SVO for 25L (it's been a while).
Their ATC solution was to declare NDB apch in progress in VMC+ conditions, when the close holding points were needed to keep high flow. .
Not saying better or worse, just in agreement with w. that it is a major issue.
Somewhat related: Approaching LGW behind an A380, the controller would offer an RNAV approach with the standard super-separstion, or an ILS which required (almost) additional 2 NM in trail.
Maybe someone here kept the ILS scales on during the RNAV APCH and observed what was the actual behaviour?
Their ATC solution was to declare NDB apch in progress in VMC+ conditions, when the close holding points were needed to keep high flow. .
Not saying better or worse, just in agreement with w. that it is a major issue.
Somewhat related: Approaching LGW behind an A380, the controller would offer an RNAV approach with the standard super-separstion, or an ILS which required (almost) additional 2 NM in trail.
Maybe someone here kept the ILS scales on during the RNAV APCH and observed what was the actual behaviour?
Due to the TWY - GS antenna configuration the same was an issue at SVO for 25L (it's been a while).
Workarounds can only be done by adjusting the taxiways to not lead directly to the threshold at 90°, or changing ops otherwise: displaced threshold; long looping taxiway that connects to the threshold at 0°, all departures from an intersection beyond the G/S antenna; back-taxiing from an intersection for >300m (probably not a good idea when another aircraft is inbound inside the marker - and might still produce interference). Switching to a 6° GS would put the beam angle "above" even tall aircraft that might block the signal - maybe.
All of which produce their own issues.
The concept of promoting autolands as the future due to inexperienced crew, fails to consider the busy ATC environment, the lack of ILS signal protection unless weather conditions dictate it, and therefore the potential consequences of conducting auto-coupled approaches in day to day operations.
Piloting skills..... still required.
Minimum 2 crew...still required.
Airline Management have for years belittled/discredited our Profession by reducing T&Cs, looking to increase productivity.
They have believed an increase in automation with a transition to single crew operations on large aircraft as an opportunity to reduce costs, yet time and again we see the realities of operating in an increasingly busy airspace environment prove that there is no quick fix despite the accountants wishes.
Piloting skills..... still required.
Minimum 2 crew...still required.
Airline Management have for years belittled/discredited our Profession by reducing T&Cs, looking to increase productivity.
They have believed an increase in automation with a transition to single crew operations on large aircraft as an opportunity to reduce costs, yet time and again we see the realities of operating in an increasingly busy airspace environment prove that there is no quick fix despite the accountants wishes.
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nike :
I was attending a presentation 2 years ago by an executive of a large European low cost operator on the introduction of the 737-8 max who said that they were planning mandating auto lands on the type where it was feasible in order to reduce go arounds and tyre wear. Did this actually materialize ? never heard anything about it since.
The concept of promoting autolands as the future
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Thanks to everyone here that posted. We just flew into HKG for the normal 07L landing. During the arrival, ATC changed our arrival and told us to land on 07R. They gave us the verbal GS warning, as described above. We saw an Emirates aircraft approaching the hold short line, which could disrupt the GS signal. We turned off the autopilot, and followed the PAPIs just in case the GS signal was disrupted, and landed uneventfully. The EK aircraft did not get near the hold short line before we landed, and we saw no GS distruption.
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Often though they are using 7R at night, or early mornings. When it happened to me it was probably the most violent autopilot malfunction I had ever experienced, even though we were familiar with warning will take you by surprise.
Clicked off autopilot And recovered....but when I read possible gs interference this is not what my mind conjured up.
Clicked off autopilot And recovered....but when I read possible gs interference this is not what my mind conjured up.
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Would not the simplest solution in HKG be to only line up airplanes on 7R from J and H when using the runway in mixed mode? Just make all GA and Cargo aircraft cross at J6 and join the cue on the north side of the runway. By not using K1 you would avoid any issues.
Or just hold aircraft at the Cat 2 hold. I don’t understand why that is so hard. If you time it right then it makes absolutely no operational impact. If the planes are that tightly spaced, holding at the CAT 2 would not make that much difference to holding at K1.
Or just hold aircraft at the Cat 2 hold. I don’t understand why that is so hard. If you time it right then it makes absolutely no operational impact. If the planes are that tightly spaced, holding at the CAT 2 would not make that much difference to holding at K1.
This is an issue that has plagued HKG for many years. Now that it's being investigated by the new investigation authority rather than the regulator, something may be done about it.
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An easy solution is to hand fly and not blindly fly momentary fluctuations in the G/S signal. Otherwise you'd might have to hold every departing aircraft at the CAT II hold line whenever an aircraft is established on the G/S. What impact would that have on the arrival and departure capacity of the airport?
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An easy solution is to hand fly and not blindly fly momentary fluctuations in the G/S signal.
LOL... I know you are being sarcastic (well I hope you are) but the real problem remains all those pilots (not just Asians) that can't fly and land an aircraft in visual conditions without the help of on board electronics (autopilot, Fight Director, etc) or external aids (GPS, ILS etc).
There are way too many pilots today that have no common sense, no real stick and rudder abilities and are nothing but little programmed robots them selves that cannot think outside the box and once a simple problem is encountered and it falls outside "their" programmed training, all things fall apart.
There are way too many pilots today that have no common sense, no real stick and rudder abilities and are nothing but little programmed robots them selves that cannot think outside the box and once a simple problem is encountered and it falls outside "their" programmed training, all things fall apart.