ILS LVPs Protected Area. Loss of GS signal

[Pin Head]

Hi

Lost the GS signal on a practice auto land recently. Would a parralel runway operation and crossing aircraft could have caused this or traffic holding at the landing runway holding point contributed also.

Is there extra protection for loss of GS info for a dual channel approach over a single channel approach?

Regards

Pin

[Gonzo]

Where were you flying into?

[yarrayarra]

Glide slope aerial is adjacent to the touchdown zone so, assuming any crossing runway is past there, no interference would be possible. Ideally the glidepath aerial is on the opposite side to any parallel taxiway for that runway otherwise aircraft approaching/holding at the holding point for the runway in question could interfere with the signal being radiated- so called multipath interference.

[underfire]

I have seen the interference with the parked/taxi data with the A380 for LHR/FRA and it is significant, especially with the tail turned.

http://i.imgur.com/0vBPPwJ.jpg

http://i.imgur.com/BW9Bmyr.jpg

EDIT: Cyan line is CAT III tolerance

[Pin Head]

bangkok don meung

we had a cloud base of 300aal. Signal went at 500Ft.

Flew the a/c manually to an uneventful landing.

Should I have gone around?

[*Lancer*]

I've seen massive unscheduled G/S swings with an aircraft passing the antenna a number of times, so a total failure or the receiver invalidating the signal isn't unreasonable. Similar happens with an aircraft crossing the upwind (LOC) end.

With a loss of signal you can use the G/S out (LOC only) minima, although I'm guessing it was higher than 250' AAL. What would you have done in real CAT2/3 conditions?

[Gonzo]

OP refers to loss of GS, so references to LOC fluctuations is a bit spurious.

Depending on which runway was in use for arrivals, I can see a situation where an aircraft was inside the GS critical area. One of the runways at LHR has a taxiway crossing through the GS critical area which we cannot use if an aircraft is within 15nm from touchdown and using the ILS.

[de facto]

Pin head,

Did you advise ATC about your practice autoland?
Does your company have a list of "unstable" criteria?
Do you think being in IMC(you state that ceiling was 300 ft and failure occured at 500) and not having a glide information should not be unstable?
What did you brief?
What does Boeing state for
loss of signal/AP disengage light in IMC during Auto land config?
Loc has redundancy for loss of power in a channel,not glide slope and definitively no protection against signal distortion due to an aircraft entering cat2/3 sensitive area.

So yes a GO around should have been executed...

[Cows getting bigger]

Echoing some earlier comments.

If you're flying a CAT III, ATC need to know. The protected area is significantly different and there's potential for different holding points etc.

Loss of G/P at 500ft on auto land? There's only one thing to do there, especially if IMC.

Underfire, nice graphs. Aerodata?

[Capn Bloggs]

we had a cloud base of 300aal. Signal went at 500Ft.

Surely the ILS-protected area rules would have been in force with that cloudbase?

[Gonzo]

300FT....CAT I protection (critical areas) yes, CAT II/III protection (Sensitive areas) no.

Well, that's in the UK.

In fact at LHR we only now provide Cat III protection according to RVR 550m or less, there is no cloud trigger for entering ATC LVP.

[FullWings]

we had a cloud base of 300aal. Signal went at 500Ft.

Flew the a/c manually to an uneventful landing.
Purely in the spirit of inquiry: did you have any visual references at 500’ and if not, what were you using as guidance?

[Derfred]

Loss of GS in IMC at 500ft - and you didn't go-around?

Your question is irrelevant - single channel, dual channel, or manual flight - loss of GS in IMC means go-around, unless you can revert to a LOC minima (which will be above 300').

In my airline you would probably be out of a job and in my country you would probably be prosecuted for willful and reckless endagement of life, which could mean jail time.

Have a look in your company manuals and your country's regs for mandatory go-around rules. It's pretty clear where I live and work.

[B737900er]

Didn't your AWOPS training tell you that fluctuations can happen when the sensitive areas are not protected? Seriously who is this clown? The questions asked at times are worrying, especially now we know he's flying around the tropics. That can be a tough area to fly in.

[underfire]

Cows, ref this document...very interesting research.

Assessment of ILS protection areas impact on large aircraft operations (http://www.icao.int/EURNAT/Other%20Meetings%20Seminars%20and%20Workshops/MISC/A380%20workshop/Assessment%20of%20ILS%20protection%20areas%20impact%20on%20l arge%20aircraf%20operations%20V1.3%20web.pdf)

[de facto]

my airline you would probably be out of a job and in my country you would probably be prosecuted for willful and reckless endagement of life, which could mean jail time.

I am not sure in which country you work in,but i guess not in Australia.
As long as no damage to aircraft/property/pax has ocurred,who would sue him to send him to jail,you?
Reckless driving is a company issue and should be dealt with via SRS..
But i guess where you work,no pilots file any due to fear of harsh punishment?
I am with 737900ER,in that i am having great and worrying doubts on PIN proficiency in general,showing serious lack of basic knowledge,visible from his multiple posts.
Trying to find answers here shows at least some kind of awakening and lets hope it wont be too late.

Now,after 100000 hours+ he recently claimed to have,one is entitled to wonder where he has been trained and if he really got any in the first place.
Apparently,close to an upgrade and flying in Asia,i would guess Lion Air...
Now i hope this major mishap will teach him a serious lesson especially if his airline has no serious SRS in place.
Yet,i wonder why the other pilot hasnt reacted either...

[Derfred]

I am not sure in which country you work in,but i guess not in Australia.
As long as no damage to aircraft/property/pax has ocurred,who would sue him to send him to jail,you?


Not me, but CASA would.

http://www.pprune.org/australia-new-zealand-pacific/133152-qantas-pilots-charged-over-reckless-takeoff.html

[de facto]

seems like the "Act",if i read correctly,goes from fines to a max of licence suspension.
Have not seen any jail time,,,i know there are many chinese in Australia though, but not chinese yet...