App says GS out, appears to be working...

kiloalpha

Well-Known Member
Real life from today...

Approach told me the glideslope was out of service while being vectored for the ILS. While it appeared to be working (it was able to center at the FAF and I could follow it to minimums,) I chose to proceed with caution and use the localizer minimums. It kept me at 500 feet but I found a hole over the approach lighting and was able to land.

So, what do you do if the GS is said to be out but really isn't and isn't notam'd out of service?
 
Put this to the sniff test. Do you want to follow something towards the ground that may not be working?

NOTAMs are not instant, and with Lockhead running things, usually not correct.
 
Real life from today...

Approach told me the glideslope was out of service while being vectored for the ILS. While it appeared to be working (it was able to center at the FAF and I could follow it to minimums,) I chose to proceed with caution and use the localizer minimums. It kept me at 500 feet but I found a hole over the approach lighting and was able to land.

So, what do you do if the GS is said to be out but really isn't and isn't notam'd out of service?

A lot of times, the Glideslope will be notamed out of service while someone is working on it, or when one of the components of the GS is inop. The best way for them to work on it may not include shutting the thing off. Sometimes they need to test the integrity of the signal from ground based means, and you can't really do that while the thing is working. I've followed it in VFR a couple times at ACE when the glideslope was called inop, and didn't really have a problem, no noticeable differences. However, I'm sure as hell not going to trust my life to a piece of equipment that may or may not be functioning properly.
 
No way would I depend on it. follow it while flying localizer minimums, probably. But depend on it? No. It might seem to be working, but if you're in the soup....ugh. No thanks.
 
We had a situation going into SHD one day. The GS was NOTAMed OTS, but approach asked us if we'd be able to take a longer vector and shoot the approach to check the GS. It was VMC, so we agreed to do it.

When we canceled IFR in the traffic pattern, we were sure to use the word "appears" as to cover our ass if someone came along and shot the approach the next day in IMC and crashed.

"It appears the glide slope is working". I'm not Flight Check, so I surely wasn't going to say that it was definitely working.
 

Things could have a rats tail?

Accident (Continued)
Occurrence #1: OVERRUN
Phase of Operation: LANDING - ROLL
Findings
1. (C) MISSED APPROACH - NOT PERFORMED - FLIGHTCREW
2. (F) FATIGUE - PILOT IN COMMAND
3. (F) AIRPORT FACILITIES,RUNWAY/LANDING AREA CONDITION - OTHER
4. (F) PROCEDURE INADEQUATE - COMPANY/OPERATOR MANAGEMENT
----------
Occurrence #2: ON GROUND/WATER COLLISION WITH OBJECT
Phase of Operation: LANDING - ROLL
Findings
5. OBJECT - ANTENNA
Findings Legend: (C) = Cause, (F) = Factor​
File No. 24061 02/18/2007 Cleveland, OH Aircraft Reg No. N862RW Time (Local): 15:06 EST


The National Transportation Safety Board determines the probable cause(s) of this accident as follows.
the failure of the flight crew to execute a missed approach when visual cues for the runway were not distinct and identifiable.

Contributing to the accident were
(1) the crew's decision to descend to the ILS decision height instead of the localizer (glideslope out)
minimum descent altitude;
(2) the first officer's long landing on a short contaminated runway and the crew's failure to use reverse thrust and braking to their maximum effectiveness;
(3) the captain's fatigue, which affected his ability to effectively plan for and
monitor the approach and landing; and
(4) Shuttle America's failure to administer an attendance policy that permitted flight crewmembers to call in as fatigued without fear of reprisals.​
 
I have used an NDB that was NOTAMed OTS, but with a non-directional beacon you either get a signal and it works or you dont and it doesnt, there is no grey area. With a GS you may be recieveing the signal but it might be missing a component or improperly configured or be intermittent and unreliable. Like others I would not trust being that close to the ground with an unreliable signal.
 
This happened in BOS for a few days this summer. The glideslope was NOTAMed out, but appeared to be working. We all flew the localizer mins, and nobody died. That is all.

;)
 
Didn't a similar situation cause an accident in Croatia on an airforce jet. I think it was with an NDB, but had to due with unapproved use of a navaid.

In this particular situation, I would definitely use the localizer approach
 
So, what do you do if the GS is said to be out but really isn't and isn't notam'd out of service?

in actual conditions- same thing you did

if it's a practice approach in VFR, or on an IFR flight plan in VFR conditions, no reason not to follow the GS on down, imo
 
Real life from today...

Approach told me the glideslope was out of service while being vectored for the ILS. While it appeared to be working (it was able to center at the FAF and I could follow it to minimums,) I chose to proceed with caution and use the localizer minimums. It kept me at 500 feet but I found a hole over the approach lighting and was able to land.

So, what do you do if the GS is said to be out but really isn't and isn't notam'd out of service?

Ever hear of Korean Airlines flight 801 on 8/6/97, a 747 coming into Guam? 214 killed. GS was out, yet it showed up on the HSI, they followed it, and...

BOOM!!

Yes, there was a bit more to it than that but not much more.

You were wise to use the LOC minimums.

I don't give a s--t about a NOTAM. If I am told the GS is out, that is how I will treat it it, regardless of what shows on my gauges.
 
I don't give a s--t about a NOTAM.

Chances are, if you've got to use non-alphabetic characters to prove a point, it's probably in violation of our profanity rules.
 
I'm pretty sure that although it's NOTAM'd out, it can still provide erroneous readings that may seem like it's working. If it's NOTAM'd out and you go to ILS mins you are in violation and stupid. Follow the NOTAMs.
 
I don't even trust the damn things when they're not NOTAM'd anymore. ACT had a couple of crashes a few years back. Its fairly common knowledge in the mu-2 'community' that the second was caused by an erroneous glideslope indication (apparently a twin cessna had the same problem the day before...in vmc), but of course it went down as CFIT and the mitsi somehow wound up wearing the brown helmet...again.

I never thought I'd say it, but I'm glad the current ride has a 430. No way I go anywhere near even a putatively inop glideslope...I'd treat it as a nonprecision, including flying the stepdowns.
 
What the . . ?

You sound like me now. I panicked a couple of weeks ago when one of the two FMS's was broken!!

We're getting old, Lloyd. Luckily, the Legion hall still has cheap beers and walker-parking. Now someone get those damn kids off my lawn.
 
747 that attempted to follow a U/S GS a few years ago.

crash2.jpg


The aircraft crashed while executing a non-precision localizer approach to runway 6R at Agana. The crew descended below the approach profile, and struck terrain approximately 3 miles short of the runway. The crew did not understand that the glideslope of the ILS system was out of service.
 
I don't even trust the damn things when they're not NOTAM'd anymore. ACT had a couple of crashes a few years back. Its fairly common knowledge in the mu-2 'community' that the second was caused by an erroneous glideslope indication (apparently a twin cessna had the same problem the day before...in vmc), but of course it went down as CFIT and the mitsi somehow wound up wearing the brown helmet...again.

I never thought I'd say it, but I'm glad the current ride has a 430. No way I go anywhere near even a putatively inop glideslope...I'd treat it as a nonprecision, including flying the stepdowns.

besides, with the 430, you just set your own vnav profile from the FAF to the MAP. and dont even worry about the GS, right?
 
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