Dan Air 1008

[Wodrick]

Today is the 40th Anniversary of the Tenerife Disaster.
I was on the shift that departed the flight.
This is the Memorial in Manchester Southern Cemetery. No remembrance this year of course.

[Boac]

Before my DA time, but I remember it well. It caused a significant change in our operating procedures.

[TheGreenGoblin]

I remember reading that an unpublished holding pattern was a factor in the causal chain in this very sad accident?

[Boac]

A true Swiss cheese model. The accident report is https://www.gov.uk/aaib-reports/8-1981- ... april-1980

A combination of misunderstanding, poor ATC, too high an entry speed for the hold and an unpublished hold all rolled into this. It is assumed the crew may have interpreted the hold as 150 outbound when it was 150 inbound, and of course no published hold data to check. The hold at FP was unexpected and there was very little time to brief and agree it. The Captain turned the wrong way for the hold entry taking them towards the mountain.

[TheGreenGoblin]

A true Swiss cheese model. The accident report is https://www.gov.uk/aaib-reports/8-1981- ... april-1980

A combination of misunderstanding, poor ATC, too high an entry speed for the hold and an unpublished hold all rolled into this. It is assumed the crew may have interpreted the hold as 150 outbound when it was 150 inbound, and of course no published hold data to check. The hold at FP was unexpected and there was very little time to brief and agree it. The Captain turned the wrong way for the hold entry taking them towards the mountain.

It seems that even if the Captain had taken up the hold on the correct radial, at the cleared altitude, he might still have come unstuck as the radius of the turn required by the ad hoc procedure was too small to be safely flown.

https://mayday365.wordpress.com/2015/04 ... ight-1008/

[Boac]

Very difficult to unpick, and I think that 'sketch' of the two holds in the Montreal Gazette you link is wrong - the 'correct' hold should have been left turns - the article portrays right, and the super-imposition of the article on the BA chart is also incorrect, showing a right turn hold and the 'FB' beacon, not the FP! In addition the 'possible route' depicted is wrong since the actual would have been further west nearer to 4950 spot height. Good old journos!. The AIB appendix shows it far more correctly. Why on earth pick a Canadian paper..... and the whole 'MAYDAY365' page has more typos and other errors?

It is by no means certain that the crash would have happened had the procedure been flown at a higher speed, although obviously the margins would be much reduced, and starting the whole thing from SOUTH of the FP did not help.

The entry should have been right turn after passing the FP either onto 330 and a right turn back to the FP or onto (a nominal) 360 and then left back to the FP to continue the hold. Even at the higher speed that should have avoided the cumulo-granite. I think the 'unexplained' comment from the FE about '3' reflects the feeling that he recognised the Captain was flying a (poor) direct entry (Sector 3) join on the 'assumed' hold - outbound on the 150 - (whether he was 'nudging' because he recognised the error or also 'convinced' we will never know.)

This FP 'hold' was presumably some sort of 'local' unofficial procedure and probably 'safe' if flown correctly, and moreover if the Captain had not reversed his left turn following the GPWS the aircraft may well have not crashed.

A tragic accident and as I said, full of 'ventilated' cheese. After the accident the 'newer' Tenerife South airport became the norm.

[TheGreenGoblin]

Very difficult to unpick, and I think that 'sketch' of the two holds in the Montreal Gazette you link is wrong - the 'correct' hold should have been left turns - the article portrays right, and the super-imposition of the article on the BA chart is also incorrect, showing a right turn hold and the 'FB' beacon, not the FP! In addition the 'possible route' depicted is wrong since the actual would have been further west nearer to 4950 spot height. Good old journos!. The AIB appendix shows it far more correctly. Why on earth pick a Canadian paper..... and the whole 'MAYDAY365' page has more typos and other errors?

It is by no means certain that the crash would have happened had the procedure been flown at a higher speed, although obviously the margins would be much reduced, and starting the whole thing from SOUTH of the FP did not help.

The entry should have been right turn after passing the FP either onto 330 and a right turn back to the FP or onto (a nominal) 360 and then left back to the FP to continue the hold. Even at the higher speed that should have avoided the cumulo-granite. I think the 'unexplained' comment from the FE about '3' reflects the feeling that he recognised the Captain was flying a (poor) direct entry (Sector 3) join on the 'assumed' hold - outbound on the 150 - (whether he was 'nudging' because he recognised the error or also 'convinced' we will never know.)

This FP 'hold' was presumably some sort of 'local' unofficial procedure and probably 'safe' if flown correctly, and moreover if the Captain had not reversed his left turn following the GPWS the aircraft may well have not crashed.

A tragic accident and as I said, full of 'ventilated' cheese. After the accident the 'newer' Tenerife South airport became the norm.

Oh thank, thank you, thank you! I was being driven mad by that diagram which I knew had to be be wrong as it wasn't left hand and didn't seem to incorporate the fix properly! I was in the process of drawing a diagram, with sectors, to post the question here! I even dreamed about it. I think I might be a little OCD!

To have an completely non standard approach thrown at one late in such a situation must have stressed the crew to the max and, as you say the sloppy flying didn't help! I assume they were catching the aircraft in front up and ATC threw in the hold at the last minute to ensure separation.

Sector 3 procedure (direct entry):

Upon reaching the fix, turn right and follow the holding pattern
Entry procedures to a non-standard holding pattern requiring left turns are oriented in relation to the 70˚ line on the holding side,just as in the standard pattern. Thus the corresponding entry procedure diagram for a non-standard holding pattern is a mirror image of that for the standard pattern.

[Boac]

It is apparent that the high speed of the 727 was a factor, as you say, for ATC as well and this was one facet of its contribution to the accident.

The DA 727 fleet (with a reputation for 'not hanging around') was quite different in its way of operating to the 737 fleet that I joined - with a far more 'relaxed' way of operating and no (or very very few!) cases of "the F/O does radio and fuel (and I fly and talk with the FE)." which can reduce crew inter-action significantly.

It was very amusing watching the 727 Captains joining the 737 fleet ("transfer or P45"!) with their built-in hatred of the 737 fleet (aka 'The Slug') and not being used to allowing their (equally-competent) 727 F/Os to 'operate' normally. The first few sectors on line for them was a hard task for the 737 F/Os (requiring much application of 'CRM'))

[TheGreenGoblin]

It is apparent that the high speed of the 727 was a factor, as you say, for ATC as well and this was one facet of its contribution to the accident.

The DA 727 fleet (with a reputation for 'not hanging around') was quite different in its way of operating to the 737 fleet that I joined - with a far more 'relaxed' way of operating and no (or very very few!) cases of "the F/O does radio and fuel (and I fly and talk with the FE)." which can reduce crew inter-action significantly.

It was very amusing watching the 727 Captains joining the 737 fleet ("transfer or P45"!) with their built-in hatred of the 737 fleet (aka 'The Slug') and not being used to allowing their (equally-competent) 727 F/Os to 'operate' normally. The first few sectors on line for them was a hard task for the 737 F/Os (requiring much application of 'CRM'))

The accident seems to have shaken up a lot of areas, from international co-operation and oversight of accident investigations, through to ATC and aircraft radio communication protocols, CRM, the promulgation of approach procedures etc. etc. etc.

Whatever the case, a terrible accident and grievous for all concerned and still is today I am certain. I listened to that CVR segment again and I just felt very sad. RIP.

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As for the interesting anecdote, was it a case of from 'The Hot Rod' to 'The Slug' for some?

[Wodrick]

grievous for all concerned and still is today I am certain

If you were involved .........
The Captain lived in the South Midlands, too far to commute, when flying he stayed in the old Airport Hotel, the Robinson's pub.
He had a corner there like ExA's chair, had many a pint there.
The FE always dropped in the crew room for a brew and to talk cars, he had a Capri.
From SM
One of the girls was a check, they were not rostered and could pick their flights. It was normal to pick something short like PMI, why she had picked TFN is unknown.
Another of the girls was 15 min out of hours, she was there as a favour to crewing.
It goes on and is still very upsetting.
The engineering management didn't tell the active shift, we heard on the local radio station.