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itchybum
27th Apr 2005, 08:47
Can anyone decipher what this ****wit reporter is trying to say?


A mistake by an air traffic controller was among a number of communication lapses that plunged a commercial flight from Melbourne to Adelaide into a rapid descent last year, a report into the incident has found.

The Australian Transport Safety Bureau (ATSB) said the Boeing 737 was approaching Adelaide on March 9 using an instrument landing system (ILS) when it went into a rapid descent, falling at about 2,000 metres per minute.

The pilot managed to regain control of the aircraft, pull out of the descent and land without incident.

The ATSB said the air crew had been directed by an air traffic controller to use ILS even though there had been previous notifications that the system was being worked on and was not to be used that day.

It said about 40 seconds before the plane entered the ILS glide path the pilots were told that they were cleared for the ILS approach.

"The pilot in command acknowledged and read back the clearance," the ATSB report said.

"The controller later reported that at the time the fact that the glide path was not available had slipped his mind.

"The inadvertent slip by the approach controller was the final action of a number of lapses or omissions that led the pilots to believe the ILS was available, despite previous advice."

As a result of the incident the aircraft operator issued two safety briefings to pilots and an Airservices (Airservices) Australia investigation found that while there were adequate safeguards in the system, many had been breached.

swh
27th Apr 2005, 09:06
Maybe the ILS was radiating in test mode, no real slope, and the autopilot would have thought it was on-slope all the time..6000fpm seems a little high, the upper false glideslope is around that.

Jungmeister
27th Apr 2005, 09:40
Who made up the title for this post?
("ILS Death Plunge") Was it in the media?

The report states:

Information from the aircraft’s flight data recorder indicated that the maximum rate of descent was 6,100 feet per minute and that it had descended to a radio altitude of 1,180 ft above ground level (2,000 ft above mean sea level) before resuming the approach profile.


The complete ATSB report can be viewed at
http://www.atsb.gov.au/aviation/occurs/occurs_detail.cfm?ID=612

amos2
27th Apr 2005, 10:12
Oh! Please, please, please...

this can't be true , Surely??

but if it is...

God help us all that go flyin' in the back end!





:{

Capn Bloggs
27th Apr 2005, 12:59
If you want to read something REALLY scary about ILSs radiating false glideslopes when they're switched off without pilots knowing, get hold of the AirNZ 767 in the South Pacific.

Very sobering stuff.

v1rotate
27th Apr 2005, 21:05
Did the pilots identify the ILS when they tuned it? Would have thought that they would get a "TST" ident.

swh
27th Apr 2005, 23:39
v1rotate,

Not always.

:ooh:

julietmikepapa
28th Apr 2005, 02:07
NZ60 767 is indeed sobering stuff - when on test you will pick up glideslope from anywhere, and if you are descending will continue at at least that rate if not more. Ident only radiates on LLZ transmitter, therefore you NEVER know exactly what the glideslope is doing, therefore x-check, x-check, x-check...

If you can be bothered to wade through it... http://www.caa.govt.nz/fulltext/Occurrence_Reports/00-2518/Pages_167-203_Occurrence_Report_00-2518.pdf

If you can get hold of the Air NZ video that they put together, and they have made available to airlines worldwide, it is well worth the watch.

AerocatS2A
28th Apr 2005, 06:00
Did the pilots identify the ILS when they tuned it? Would have thought that they would get a "TST" ident.

We discussed this incident at a recent work meeting.

Because the ILS ident is on the LLZ and the LLZ was still available, its ident was ok. However the glideslope was radiating in test mode (which was NOTAM'd) and apparantly gave a false fly down indication which the aircraft autopilot faithfully followed.

OzExpat
28th Apr 2005, 07:55
Doesn't AsA put a DME Distance Vs Altitude tabulation on their charts any more? :uhoh:

amos2
28th Apr 2005, 09:20
Yeah!..makes you wonder, doesn't it Oz? :confused:

v1rotate
28th Apr 2005, 09:28
Did the ATIS mention that the approach was a LLZ/DME approach? I would have thought that was important enough to include in the ATIS :confused:

Reading the NOTAMS would also help :ooh:

Capn Bloggs
28th Apr 2005, 11:01
Ozexpat,

It is (as you would see on the AsA website charts), but it wouldn't have helped in this case. The jet dived at the ground, literally. One doesn't need a 300x profile chart to tell you that!

The CATIS at ADL has always been a pox. It also raises the issue of controller's seemingly blaise attitude to "make ILS" approach when it's gin clear and we were never told that we could expect one anyway, as happens here often. Also, the frequent dribble on the ATIS about irrelevant stuff that clouds the real info eg "RWY XX not available...XX ILS not available..." der.

As usual, all the holes almost lined up.

I'd like to know what the two Virgin bollockings to the troops were!

mr hanky
28th Apr 2005, 23:53
Very mysterious.

6000fpm at approach speed means a pitch attitude of about 20 degrees nose down.:uhoh:

And yet, in what must be a first for Australian aviation, not a single terrified passenger appears on TV to tell us how they were plummeting at the ground and thought they were going to die.

As the Americans say, go figure...