Cabin Smoke & Fumes - CVR Maintenance Criticised?

[Capot]

The CAA has just published a follow-up to an MOR. It concerns a BA 747-436 at Phoenix in June 2009.


The engines were being started during pushback when fumes and smoke were noticed in the cabin. The commander decided to return to stand; however, there was some delay while the tug was reconnected. The intensity of the fumes increased and as the aircraft came to a halt on stand an emergency evacuation was carried out. An extensive engineering investigation after the event was not able to provide any explanation for the origin of the fumes. The aircraft was returned to service and no further instances have occurred.This led to a recommendation that;

It is recommended that British Airways plc review their procedures and training of flight and maintenance crews to ensure the timely preservation of Cockpit Voice Recorder recordings in the event of a reportable occurrence, in accordance with ICAO Annex 6 Part I, 11.6 and EU-OPS 1.160. The procedures and training should provide the necessary information and skills to identify when reportable accidents and serious incidents occur, and implement the necessary tasks to preserve flight recordings in a timely manner.The CAA's response is a classic to connoisseurs of the CAA's way;

This Recommendation is not addressed to the CAA. Status Closed.So another recommendation was made by AAIB;

It is recommended that the Civil Aviation Authority review the relevant procedures and training for UK operators, to ensure the timely preservation of Cockpit Voice Recorder recordings of a reportable occurrence is achieved in accordance with the requirement of ICAO Annex 6 Part I, 11.6 and EU-OPS 1.160.To which the CAA responded


The CAA accepts this Recommendation. Following publication of EASA Service Information Bulletin 2009-28 detailing the maintenance requirements for CVR and FDR systems, a review of CAP 731 is being undertaken. This review has highlighted a need to introduce a new chapter in CAP731 on CVR maintenance requirements. As a result of this safety recommendation, the need will also be emphasised to ensure preservation of recorded data, by securing the power supply to the CVR / FDR in the event of an incident or accident. The proposed timescale for publication of the revised CAP 731 is end of October 2010. To cover the maintenance / continuing airworthiness management aspects of this recommendation, CAA will publish an AIRCOM to highlight the need for Operators, and their Part M subpart G organisations, to include procedures for preservation of CVR and FDR data in their Continuing Airworthiness Management Exposition. The AIRCOM will include reference to the need to ensure this subject is also appropriately covered in the Ops manual. The proposed timescale for publication of the AIRCOM is end of August 2010. Status Open.Now, I knew nothing about this incident, and still know only what is written above.

But how exactly did a problem with fumes and smoke that was serious enough to warrant an emergency evacuation get dismissed with the words "...investigation ...not able to provide explanation"? Surely an explanation needed to be found?

And what exactly happened in the incident which;

a) Made the CVR very important to the investigation and

b) Led the AAIB to recommend that BA's procedures to ensure the timely preservation of recordings in the event of a reportable occurence should be reviewed and

c) Led the CAA, when finally jerked out its stupor by the AAIB, to take a number of quite drastic steps to deal with the problem with keeping CVR recordings properly, something I thouight had been sorted out long ago?

Can anyone throw any light on this? It seems rather odd.

[172_driver]

Here is a long thread about the occurrence: http://www.pprune.org/rumours-news/380937-ba288-emergency-phoenix.html

[happybiker]

Capot

AAIB Safety Rec 2010-11 was not addressed to the CAA in the AAIB bulletin so the CAA response is as expected.

AAIB Safety Rec 2010-12 is addressed to CAA and they have published their response as per your post.

Both Safety Recs were published in the same AAIB bulletin 6/2010 so the CAA do not appear to be ignoring the problem but responding to the recommendation the AAIB made to them. http://www.aaib.gov.uk/cms_resources.cfm?file=/Boeing%20747-436,%20G-CIVB%2006-10.pdf

The reason why the CVR is important in this case is that the communications recorded at the time of the incident was overwritten and the AAIB felt that if it had been preserved it could have contributed to a more effective and conclusive investigation. I would not disagree with that.

The Cockpit Voice Recorder (CVR) installation is designed to record audio information when the electrical power is selected on the aircraft, and the CVR fitted is designed to preserve at least the last 2 hours of audio information. Flight crew communications were considered important to this investigation and so the CVR should have provided further insight. However, the CVR continued to run during the maintenance activities carried out after the event, so all the audio information relating to the event was lost.

[BOAC]

I seem to recall there were some allegations of PAs not made or some lack of communication from f/deck to cabin or cabin to cabin? I'm sure it's all in the thread.

[Capot]

Sorry, fellas, I did a half-hearted search before starting the thread but missed the thread linked above.

Reading it answers the questions, pretty much, so I'll delete this thread unless anyone adds anything this evening.

[lomapaseo]

Reading it answers the questions, pretty much, so I'll delete this thread unless anyone adds anything this evening.

Please do not delete threads that add updated and relevant information. Many of us can benefit from updates like this.

Leave it up to the Moderator to merge a thread if it needs linking to a specific topic.

[lomapaseo]

All true IGH

But once the aircraft is turned over to maitenance it should be part of their check list. Thus the recommendation is aimed at that side of the equation.

[john_tullamarine]

Please do not delete threads

May I echo lomapaseo's thought.

Used to be that folk could delete threads even accidentally (delete the first post and the thread went with it) but now a deleted thread is tucked away where the moderators can rescue it.

In general, if you would like a thread deleted for some good reason, send a note to the relevant moderators .. otherwise, certainly in this forum, deleted threads normally are undeleted by the moderators. Main concern is that most threads have a wider interest readership than the original poster, standing alone.

Erasing the CVR and accessing the FDR for investigation is a curly matter. In many jurisdictions, post incident access is quite restricted, especially if the crew are available to provide evidence. Damned if you do, damned if you don't with this one .. a significant consideration is encouraging crews to participate actively in safety programs .. the implied threat of "after the event" mischief with CVRs may or may not assist this aim.