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747 at YHZ


blues deville

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1 hour ago, Southshore said:

I must be missing something here. Wind was M260 16G21. By any measure  that is a small headwind on Rw23. Where is this quartering tailwind chit chat coming from?  If a light wind (for here) with a massive 5 kt gust is a problem, I have a tip for ya - don't come here...ever.  There is another issue at play here which will come to light soon enough.

Runway 23 CAT2 ILS has been OTS for months, the threshold is displaced and the RNAV minimums are raised.  The only precision approach into YHZ for months has been the CAT1 ILS to 14. Hence the quartering TW and overrun on 14, not 23.

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2 hours ago, seeker said:

Well, it was a quartering TW for runway 14.  The crew decided that a slight quartering TW on the shorter, wet, runway with an ILS was a better option than dealing with an RNAV approach to a displaced threshold on the longer, into wind runway.

You are correct. Slight tailwind.

Note to self - do  not respond while mostly asleep

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As I mentioned above (again not a 747 pilot) I loaded the weather for the date and time into the sim and attempted the approach from 10NM.  Not bad for the most part but close to the ground the tailwind was noticeable.  Failed the approach the first two times and barely kept is from going off the end the third time and that wasn't pretty (well none were pretty from short final onward.)

 

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2 hours ago, boestar said:

As I mentioned above (again not a 747 pilot) I loaded the weather for the date and time into the sim and attempted the approach from 10NM.  Not bad for the most part but close to the ground the tailwind was noticeable.  Failed the approach the first two times and barely kept is from going off the end the third time and that wasn't pretty (well none were pretty from short final onward.)

 

It’s quite possible the pilot flying may have had limited experience too and perhaps their landing distance calculation wasn’t perfect either. Under those conditions it would have to be error free. No floating. No delay on on reverse or brakes.

Will also be interesting to know if the aircraft had any deferred items such as rev thrust or brakes etc.

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6 hours ago, blues deville said:

It’s quite possible the pilot flying may have had limited experience too and perhaps their landing distance calculation wasn’t perfect either. Under those conditions it would have to be error free. No floating. No delay on on reverse or brakes.

Will also be interesting to know if the aircraft had any deferred items such as rev thrust or brakes etc.

It was also dark and late in the night, other possible contributing factors.

 

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So, standard caveats; I never flew a 747, we don't know all the facts, etc, etc.

The information, as I understand it, is that the aircraft was empty, that it had flown in from ORD and that the wind when they were arriving in the YHZ area was a direct crosswind and that it swung to a slight tailwind late in the approach.  What's the landing distance for an empty 747 on a wet runway at sea-level?  I don't know but I looked at a few online sources and 7700' should be long enough.  The crew thought it was long enough.  My feeling is that it will come down to;  the tailwind component was stronger than anticipated and/or not accounted for correctly in the landing distance calculation, there was some mechanical fault either pre-existing or which presented itself during the landing or poor technique.

The more interesting question for me is not why the aircraft overran the runway but why the crew chose to do that approach rather than an RNAV 23.  Was the aircraft equipped for RNAV approaches, were the databases up to date, was the crew properly trained for RNAV approaches?  The issue of the displaced threshold is significant.  Flying an RNAV approach to a displaced threshold, at night, with no vertical guidance is not a trivial matter.  Yes, a properly trained crew should be able to do this and other crews did it just before the accident.

Personally, I think the ultimate "cause" of the accident will be whatever it was that prevented the crew from doing the RNAV 23; aircraft not properly equipped, crew not properly trained, company not having procedures for conducting a visual landing without vertical guidance.  Some combination of these factors made the crew choose an ILS to a shorter, wet runway with a tailwind as being the better option. 

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12 hours ago, AIP said:

It was also dark and late in the night, other possible contributing factors.

 

Definitely a factor.

I’ve done this same ORD-YHZ-ANC route before and it’s a cargo run that changes operators from time to time. The scheduled arrival time in YHZ is well planned to include a tech stop/crew change in ANC and then further west to your Asian destination. There is no consideration to the body clock’s of the flight crew. It’s all about the cargo delivery especially with this time expiry seafood. Always light if not empty into YHZ but I never had to use the shorter runway in the middle of the night when tired and jet lagged. 

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4 hours ago, blues deville said:

Definitely a factor.

I’ve done this same ORD-YHZ-ANC route before and it’s a cargo run that changes operators from time to time. The scheduled arrival time in YHZ is well planned to include a tech stop/crew change in ANC and then further west to your Asian destination. There is no consideration to the body clock’s of the flight crew. It’s all about the cargo delivery especially with this time expiry seafood. Always light if not empty into YHZ but I never had to use the shorter runway in the middle of the night when tired and jet lagged. 

Exactly.  All the more reason to have the airfield properly equipped and functioning.

I landed in YHZ very early morning (04:00) many years ago (I am sounding old). Weather was about 300' or so visibility reduced, 3/4 -1 I would recall.

Did the ILS on 23 after being up all night, finally broke out and landed/ No Cat II or TDZ lights were one.  When we queried the tower, the reply was astonishing, 

"It is not Cat II weather".

It was like he was paying for the electricity himself !!!!!!!!!!!!!!, would have made for an interesting report had something happened imo. 

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Quote

It was like he was paying for the electricity himself !!!!!!!!!!!!!!, would have made for an interesting report had something happened imo.

I think it did make for an interesting report recently, when the lights never quite made it to strength 5 as advertised....

Something is definitely up at YHZ....

Vs

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3 hours ago, AIP said:

Exactly.  All the more reason to have the airfield properly equipped and functioning.

I landed in YHZ very early morning (04:00) many years ago (I am sounding old). Weather was about 300' or so visibility reduced, 3/4 -1 I would recall.

Did the ILS on 23 after being up all night, finally broke out and landed/ No Cat II or TDZ lights were one.  When we queried the tower, the reply was astonishing, 

"It is not Cat II weather".

It was like he was paying for the electricity himself !!!!!!!!!!!!!!, would have made for an interesting report had something happened imo. 

Don't get me started - the lighting on RWY 05 for the YHZ 624 crash was set at 4 - this is 25% of the intensity of setting 5!  The controller was busy and forgot to change the setting even though asked to do so by the crew.  Is that controller still working there?  This error is on the same level as anything done by the crew.

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1 hour ago, Johnboy said:

Now headed for the beer can factory. I wonder if it will be subjected to the aluminiun tariffs?

https://twitter.com/TomPodolec/status/1064305745334804480

 

I’m sure anything that could be easily removed (avionics, seats, doors, etc) were taken out. Sad to watch. 

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On 11/14/2018 at 5:45 AM, seeker said:

So, standard caveats; I never flew a 747, we don't know all the facts, etc, etc.

The information, as I understand it, is that the aircraft was empty, that it had flown in from ORD and that the wind when they were arriving in the YHZ area was a direct crosswind and that it swung to a slight tailwind late in the approach.  What's the landing distance for an empty 747 on a wet runway at sea-level?  I don't know but I looked at a few online sources and 7700' should be long enough.  The crew thought it was long enough.  My feeling is that it will come down to;  the tailwind component was stronger than anticipated and/or not accounted for correctly in the landing distance calculation, there was some mechanical fault either pre-existing or which presented itself during the landing or poor technique.

The more interesting question for me is not why the aircraft overran the runway but why the crew chose to do that approach rather than an RNAV 23.  Was the aircraft equipped for RNAV approaches, were the databases up to date, was the crew properly trained for RNAV approaches?  The issue of the displaced threshold is significant.  Flying an RNAV approach to a displaced threshold, at night, with no vertical guidance is not a trivial matter.  Yes, a properly trained crew should be able to do this and other crews did it just before the accident.

Personally, I think the ultimate "cause" of the accident will be whatever it was that prevented the crew from doing the RNAV 23; aircraft not properly equipped, crew not properly trained, company not having procedures for conducting a visual landing without vertical guidance.  Some combination of these factors made the crew choose an ILS to a shorter, wet runway with a tailwind as being the better option. 

Probably not equipped with GPS.

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