The fact that so many holes in the cheese lined up staggers me. 10000ft is not high enough to couse hypoxia and reasoned thought should have deduced the cause. I don't know at what height the a/c would be clean but I would have thought it would be a far bit before 10000ft (cabin px at which the cab alt horn sounds)įor me the give away as to the reason for the horn, is the point at which the horn first sounded. It occurs if the ground spoiler interlock valve is still open with the a/c in the air and flaps up. So perhaps someone could explain where the maintenance personnel fit into the story here? I can't see how they could be blamed?Īctually you CAN get a take-off warning in the air.

I don't know the Helios SOPs but at my outfit the auto mode selector should have been checked at least 3 times by the time 10,000' is reached, the pack switches having been reset as part of the after start sequence and checked in the A/S checks. So its not quite as clear cut as you seem to think (Edit: this sentence is garbage - I was thinking of the steady warning horn, but the rest of this paragraph is accurate!).įurthermore, regardless of the position of the pack switches/pressurisation mode selectors, I find it quite amazing that they were not reset as part of the normal procedures or caught in the normal checklist sequence. An admission, surely, that there is a problem with the design of this system? Not only that, but the config warning can sound in flight, for example retarding the thrust levers to less than 68% N1 with flaps out and gear not down will trigger it. So much so that Boeing have modified the warning horn to also trigger a light which indicates whether it is sounding for takeoff config or cabin pressurisation. As far as I can see it can only lead to a strong potential for confusion in a period where judgement is possibly impaired. Ifixplanes - I think it would be fair to say that under conditions of potential hypoxia, it is probably not a good idea to have a warning horn that has 2 meanings. I would have thought that all commercial pilots who may be involved in operating pressurised a/c ought to have had practical training concerning hypoxia. But the actual experience of hypoxia in that chamber is something I have never forgotten.Īs a professional pilot I have asked some of the new entrant pilots whether they have had hypoxia training and have been very surprised that this was not included in the syllabus for their commercial training. It was really impressed on us how vital it was to get onto oxygen should there be a pressurisation failure and the dangers of not doing so. (We had previously covered all the various physiological aspects in the classroom). During my commercial pilot training (back in 1969) we were all taken to the nearby Navy base and put in the chamber and taken up to 35,000 ft or so and then asked to do simple tasks after the oxygen was turned off.

One aspect of the Helos accident which interests me is whether either of the flight crew had had hypoxia training. If this finally brought the episode to a close, I might concur somewhat, but I suspect the mud-slinging will never stop. Having heard from various ex-Helios cabin crew about how they were abused by the public in supermarkets etc, while they were still grieving themselves over the loss of colleagues and friends, then I fully expect others will get it in the neck. If I have found a switch not in the preflight position I have never made a song and dance about it, it is my responsibility to ensure that it is correct before take-off. Whose engineering I trust completely - their job is NOT to set up the flight deck for me and my crew, they may have been under commercial pressure to get the aircraft released and back in service, some switches do get missed, packs are off to allow work underneath the aircraft etc. This has even been at some of the worlds major airlines I have had dealings with Lasham engineering since it was DanAirs engineering base, subsequently also with Astraeus, and have never had any doubts whatsoever.Īs a Captain, whenever I have entered a flight deck and discovered that the aircraft has just left the hangar, I have made sure that the cockpit prep is very thorough indeed. Obviously, the crew cannot be disciplined having paid the ultimate price, so it seems that someone else must be held responsible. If the cockpit preparation had been performed correctly, that aircraft would probably still be flying to this day. Performing any checklist wrongly is going to be punished by an inquiry. Īll I know is, that if the crew had finally woken up to what the problem was, initiated an emergency descent etc and landed safely, then they would have been held entirely responsible for the event. The accident so traumatised the entire country, not sure it will ever go away, even if they do prosecute somebody.

Helios airways flight 522 summary