Uncalibrated Ils
Joined: May 2007
Posts: 99
Likes: 0
From: Europe
Never heard about that
ILSs have to be calibrated every 6 months, if I`m not mistaken. If not I don`t think any CAA would allow it to run.
Never flew in Africa though...
Do you mean uncategorized ILS? There is one at LSZH. But thats a different story
ILSs have to be calibrated every 6 months, if I`m not mistaken. If not I don`t think any CAA would allow it to run.
Never flew in Africa though...
Do you mean uncategorized ILS? There is one at LSZH. But thats a different story
Joined: Mar 2000
Posts: 8,571
Likes: 3
From: Arizona USA
Depends on the specific regulatory authority, whether they can be used in IMC...or not.
However, in some regions, some ILS is better than no ILS, especially on those dark, visual approach nights.
Yeah, I can do 'em without the ILS, but my First Officer needs a helping hand, he realizes this and tunes the ILS for reference.
Smart guy.
And, then we have a totally different situation.
On the ILS to 18R at LOS, low ceilings reported, all coupled up, everything looks OK.
Except, at 800 agl the First Officer (flying pilot) notices that the glidepath zooms to the bottom of the HSI.
Not good.
He says...going around, trim go-around thrust, flaps 22, gear UP.
Just like he absolutely should.
Smart guy.
Experience pays off, big time, make NO mistake.
However, in some regions, some ILS is better than no ILS, especially on those dark, visual approach nights.
Yeah, I can do 'em without the ILS, but my First Officer needs a helping hand, he realizes this and tunes the ILS for reference.
Smart guy.
And, then we have a totally different situation.
On the ILS to 18R at LOS, low ceilings reported, all coupled up, everything looks OK.
Except, at 800 agl the First Officer (flying pilot) notices that the glidepath zooms to the bottom of the HSI.
Not good.
He says...going around, trim go-around thrust, flaps 22, gear UP.
Just like he absolutely should.
Smart guy.
Experience pays off, big time, make NO mistake.
Joined: Mar 2008
Posts: 198
Likes: 0
From: cloud 9
Use with caution i.e. some other form of cross-check and if you are not happy with it at any time - go-around!
Lagos - went there many times and the happiest flight was when we had to take round-trip fuel because of fuel contamination there. It's a nice feeling to have, that if you don't like it, you can go-around and go home.
Lagos - went there many times and the happiest flight was when we had to take round-trip fuel because of fuel contamination there. It's a nice feeling to have, that if you don't like it, you can go-around and go home.
PPRuNeaholic
Joined: Jun 2000
Posts: 3,255
Likes: 0
From: Cairns FNQ
I can think of 2 reasons why an ILS facility might be uncalibrated. First, the flight check didn't happen in time, second, the equipment was U/S when the fligh check was due. As pilots, you won't usually know the reason and, in any event, you'd be wise to not trust it, if it is radiating.
I don't see any problem with dialing it up for a visual approach, so long as there are ways to cross-check it's indications so that you don't depend on it. There can, after all, be any number of problems with an ILS that's in this situation.
I don't see any problem with dialing it up for a visual approach, so long as there are ways to cross-check it's indications so that you don't depend on it. There can, after all, be any number of problems with an ILS that's in this situation.
Joined: May 2007
Posts: 99
Likes: 0
From: Europe
very good videos, about the NZ60 incident in Samoa with an unmonitored ILS.
1
http://www.youtube.com/watch?v=0qaDV...eature=related
2
http://www.youtube.com/watch?v=GelRB...eature=related
cheers
1
http://www.youtube.com/watch?v=0qaDV...eature=related
2
http://www.youtube.com/watch?v=GelRB...eature=related
cheers
Thread Starter
Joined: Jun 1999
Posts: 37
Likes: 0
Confusion seems to exist in my part of the world over the difference between uncalibrated and unmonitored. As I understand it, unmonitored is fine as long as you monitor the ident. Uncalibrated; expect the unexpected.It is noticeable that Khartoum ATC are clearing aircraft for VOR approaches in all weather condtions. The ILS is notamed as uncalibrated. If it is safe to use logic in the case they obviously deem the ILS unusable.
PPRuNeaholic
Joined: Jun 2000
Posts: 3,255
Likes: 0
From: Cairns FNQ
The incident at Samoa involved an erroneous ILS. If you Google that expression, you'll find lots of information on it. While the original fault was due to a technical error made by the navaid technician/s, an incident could've been avoided by cross-checking DME distance with the nominated GP intercept point and then doing constant comparisons of altitude and DME distance - it isn't hard, even when the DME is not sited with the GP antenna.
Joined: Apr 2002
Posts: 150
Likes: 0
From: Bohol, Philippines
Quote from 411A:-
However, in some regions, some ILS is better than no ILS, especially on those dark, visual approach nights.
Yeah, I can do 'em without the ILS, but my First Officer needs a helping hand, he realizes this and tunes the ILS for reference.
Smart guy.
Wouldn't this comment be a great start to a CRM refresher?
How Captains used to be?
However, in some regions, some ILS is better than no ILS, especially on those dark, visual approach nights.
Yeah, I can do 'em without the ILS, but my First Officer needs a helping hand, he realizes this and tunes the ILS for reference.
Smart guy.
Wouldn't this comment be a great start to a CRM refresher?
How Captains used to be?
Joined: Dec 2004
Posts: 150
Likes: 0
From: Dream land
As far as i can remember back to the days where i was flying an calibration aircraft in the uk, a check was carried out three times a year.
If not calibrated, it should not be on, unless for test purposes and it should ident TST , which incidently is the same when the ILS is calibrated .
whilst calibrated it is not available for use by other than the calibration aircraft.
Monitors measure the signal strength and accuracy of the LLZ which in case of drop would then automatically change to the other transmitter, there is always two as far as i know.
Once the calibration is completed a report will be sent to the airport operator and the CAA and it will state that the ILS was within limits at the time of calibration, or not of course.
Glideslope angel could change slightly and is not nescessary 3 deg , as watertable can change and with that the glideslope angel . could be out of limits until the next calibration, without anybody knowing.
Hope that helps. this could have changed slightly as it is 8 years ago since i last flew those aircraft.
rgds
If not calibrated, it should not be on, unless for test purposes and it should ident TST , which incidently is the same when the ILS is calibrated .
whilst calibrated it is not available for use by other than the calibration aircraft.
Monitors measure the signal strength and accuracy of the LLZ which in case of drop would then automatically change to the other transmitter, there is always two as far as i know.
Once the calibration is completed a report will be sent to the airport operator and the CAA and it will state that the ILS was within limits at the time of calibration, or not of course.
Glideslope angel could change slightly and is not nescessary 3 deg , as watertable can change and with that the glideslope angel . could be out of limits until the next calibration, without anybody knowing.
Hope that helps. this could have changed slightly as it is 8 years ago since i last flew those aircraft.
rgds
Joined: Jun 2005
Posts: 244
Likes: 0
From: Here There Yonder
ILS AWAITING CALIBRATION.........Look at the Notams for most of Indonesia, Jakarta especially. I have been operating into this area for some time and CGK has had this Notam as long as I can remember. Not unlike the Malaysian FIR, with regard to the Malaysian AIP, you may have an ILS but if the high intensity approach lights are inoperative the ILS in not to be used. At the end of the day, know the rules and be aware of your responsibilities, whatever procedures you chose to take.
PPRuNeaholic
Joined: Jun 2000
Posts: 3,255
Likes: 0
From: Cairns FNQ
what is uncategorized ILS, now that you've talked about it, the one in LSZH?
Nemo Me Impune Lacessit
Joined: Jun 2004
Posts: 4,103
Likes: 5
From: Chabanais, France
From my experience the ILS radiates but the Ident is deliberately garbled or says test.
SFI145 You may have a point there, underlining that there is absolutely no substitute for experience and that it is incumbent on all crew to help out if they think there is a need, well spotted.
SFI145 You may have a point there, underlining that there is absolutely no substitute for experience and that it is incumbent on all crew to help out if they think there is a need, well spotted.
Joined: Dec 2004
Posts: 150
Likes: 0
From: Dream land
in case of LSZH RWY 28 it says on the Jeppesen plate it is due to the fact that the runway is not an instrument runway. if i remember rightly the minimum is something like 750' QFE.
My guess would be that the runway has not the appropriate lighting.
My guess would be that the runway has not the appropriate lighting.
