Helicopter down outside Leicester City Football Club
agree - very embarrassing - not to mention other (more straight-forward?) reports which appear to be taking an inordinate amount of time to be published (S-92). Kind of begs the question "is our renowned AAIB still truly independent"?
It's been a few years since I had the temerity to post on PPRUNE but something I just read caused a double-take:
"The current situation is that the actuator has been modified by replacing the right hand thread at the input end of the control shaft with a left hand thread.
This removes the repetetive inspection on the nut for loss of torque."
I used to operate a couple of 1940s ex-US Army 6x6 Studebakers. All the wheel nuts on the L/H side wheels were left-hand thread. That's 1940s: wheels: on a truck...
These days I work on vintage watches, dating back to WW1 in some cases. Almost without exception the crown-wheels, which rotate counter-clockwise, have left-hand threads. There are some esoteric exceptions, but...
It boggles my easily boggled ageing mind to think that this strategy could have been ignored on a HELICOPTER! Blimey.
"The current situation is that the actuator has been modified by replacing the right hand thread at the input end of the control shaft with a left hand thread.
This removes the repetetive inspection on the nut for loss of torque."
I used to operate a couple of 1940s ex-US Army 6x6 Studebakers. All the wheel nuts on the L/H side wheels were left-hand thread. That's 1940s: wheels: on a truck...
These days I work on vintage watches, dating back to WW1 in some cases. Almost without exception the crown-wheels, which rotate counter-clockwise, have left-hand threads. There are some esoteric exceptions, but...
It boggles my easily boggled ageing mind to think that this strategy could have been ignored on a HELICOPTER! Blimey.
That was a popular solution on truck wheels and also a few vans and high performance cars in the 1960s. This method has died out now that truck manufacturers have found out how to do proper fastener design, tighten them properly, and use reliable tightening methods. Truck wheels are generally no longer user serviceable because of the high torques and specialist tools.
Specialist fastener design is troublesome whenever the format of the threaded components prevent the male threaded element taking the role of a spring. Every standard bolt is designed to act as a very stiff spring and effective reliable tightening requires that spring to be taken to near its limit. If the format of the threaded components, or the low compressive strength of the components being retained by the threaded components, prevents taking the spring to its limit then there is a serious problem. This serious problem is extremely common, even in automotive and aviation sectors where one might think things are all sorted! This explains all the split pins, locking wire, adhesives, and so on that we are familiar with in those industries. It also explains why in modern designs we can find fasteners abandoned and they just glue it if they can!
Aviation also has the Titanium problem. This is because Ti behaviour makes it probably the worst material for threaded fasteners that is in regular use. (S-92 oil housing, Cougar 91!!!)
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The mind of a bureaucrat is different than ours.
The bureaucrat will never have a component failure while sitting at his desk investigating component failures in the world of aviation. Unless his coffee machine breaks down or something.
That is why I always say pprune discussions like this serve a useful function .... within days we will speculate on all the possibilities and it eventually gets narrowed down to just a few ..... pilots and mechanics will pay attention and maybe even check their own machines.
In the case of the Leicester crash we pretty well know what happened ... we just dont know where the finger points as to the cause .... was it people ... metal ... or design .... that is the tedious job of the investigators to sort out.
Same as the Cougar S-92 that went down in Newfoundland ..... within a few hours this forum discussion had pretty much narrowed it down to the titanium stud failure on the MTX oil filter ..... 3 years later investigators confirmed it.
For that reason I do not agree with folks who tell us not to speculate , but tell us to wait years for the official report .
Such folks have the mindset of a bureaucrat.
The bureaucrat will never have a component failure while sitting at his desk investigating component failures in the world of aviation. Unless his coffee machine breaks down or something.
That is why I always say pprune discussions like this serve a useful function .... within days we will speculate on all the possibilities and it eventually gets narrowed down to just a few ..... pilots and mechanics will pay attention and maybe even check their own machines.
In the case of the Leicester crash we pretty well know what happened ... we just dont know where the finger points as to the cause .... was it people ... metal ... or design .... that is the tedious job of the investigators to sort out.
Same as the Cougar S-92 that went down in Newfoundland ..... within a few hours this forum discussion had pretty much narrowed it down to the titanium stud failure on the MTX oil filter ..... 3 years later investigators confirmed it.
For that reason I do not agree with folks who tell us not to speculate , but tell us to wait years for the official report .
Such folks have the mindset of a bureaucrat.
https://www.gov.uk/government/news/a...sary-statement
The AAIB has now concluded its investigation into the accident and expects to publish a detailed final report in early 2023.
That took long enough.
One recommendation should be that vanity flights in to stadiums should be banned. It was lucky that just the crew and passengers died in this incident.
My deepest sympathy goes to the crew who like the incident at Beccles were servants to those in the back.
One recommendation should be that vanity flights in to stadiums should be banned. It was lucky that just the crew and passengers died in this incident.
My deepest sympathy goes to the crew who like the incident at Beccles were servants to those in the back.
That took long enough.
One recommendation should be that vanity flights in to stadiums should be banned. It was lucky that just the crew and passengers died in this incident.
My deepest sympathy goes to the crew who like the incident at Beccles were servants to those in the back.
One recommendation should be that vanity flights in to stadiums should be banned. It was lucky that just the crew and passengers died in this incident.
My deepest sympathy goes to the crew who like the incident at Beccles were servants to those in the back.
When you say Beccles I assume you mean the AW139 accident with Lord Ballyedmond? I fail to see the connection. It is clear the AW169 accident was due to a mechanical fault and the outcome exacerbated by an unfortunate impact with a small wall (that ruptured the fuel tanks). There is no suggestion of pressure on the crew or crew competence, unlike the 139 accident. So what’s your point?
i think that he hasn’t worked out yet the difference between saying no and a mechanical failure, Captaincy has the priority no matter who the talking and paying bagage Is.
That took long enough.
One recommendation should be that vanity flights in to stadiums should be banned. It was lucky that just the crew and passengers died in this incident.
My deepest sympathy goes to the crew who like the incident at Beccles were servants to those in the back.
One recommendation should be that vanity flights in to stadiums should be banned. It was lucky that just the crew and passengers died in this incident.
My deepest sympathy goes to the crew who like the incident at Beccles were servants to those in the back.
Not surprisingly, many of those who carry this grudge have themselves indulged in the joy of flying their entire career using no expenses spared government-funded hardware, were trained to the highest standards by tax payers money and were exempted from many of the inconvenient regulations that govern the world of civilian flight.
I think it's a bit rich.
'Vanity Flight' my ar5e. Football pitch-sized HLS for a Perf A departure in a highly capable machine, get a grip. Or are you suggesting that helicopters should only be used on the understanding that a new machine will suffer from a mechanical/servicing HF failure at any time? I admit that I always assume something will go wrong just to combat possible 'startle effect' and to be prepared but your mentality means choppers should only land and depart using clear areas - which kind of negates the whole point of a helicopter......#darkages
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'Vanity Flight' my ar5e. Football pitch-sized HLS for a Perf A departure in a highly capable machine, get a grip. Or are you suggesting that helicopters should only be used on the understanding that a new machine will suffer from a mechanical/servicing HF failure at any time? I admit that I always assume something will go wrong just to combat possible 'startle effect' and to be prepared but your mentality means choppers should only land and depart using clear areas - which kind of negates the whole point of a helicopter......#darkages
I spend a lot of my time in Asia where the owners of King Power have vast commercial monopolies.
The football match prior to the accident was to highlight their chief executive and promote their brand.They arrived near the stadium at the training ground 1.5 miles away but chose to leave from the stadium after the match as this departure was being screened live in Thailand.
The risk although slight of such a mishap is not worth publicity gained by such a stunt.Demands from very wealthy people often lead to the death of pilots put under pressure by their employers.
In this case it went wrong as did this accident at Beccles in Norfolk.https://www.theguardian.com/uk-news/...rd-ballyedmond
Last edited by Mike Flynn; 29th Oct 2022 at 19:33.
Stunt?
Did any authority suggest there was a violation of any Rule or Regulation?
Did any authority suggest there was a violation of any Rule or Regulation?
You simply cannot compare this accident to the Norfolk one. This was mechanical failure, the other was pilot error/CFIT of a perfectly serviceable helicopter.
Yes, I agree, if this helicopter took off from a 2km runway and the bearing gave up soon after lifting, then maybe just maybe the outcome may have been different (but not vastly). If the bearing gave up on approach to a 2km runway it could have ended up in someone's front room.
We mitigate against risk as much as possible every time we fly, but if we continually fly a helicopter like a plane, we may as well get a plane.
If you want to mitigate risk to zero, then lock the hangar doors, eat Ryvita and drink tomato juice. 10 years later write a 1 page book on how interesting your life is!
Yes, I agree, if this helicopter took off from a 2km runway and the bearing gave up soon after lifting, then maybe just maybe the outcome may have been different (but not vastly). If the bearing gave up on approach to a 2km runway it could have ended up in someone's front room.
We mitigate against risk as much as possible every time we fly, but if we continually fly a helicopter like a plane, we may as well get a plane.
If you want to mitigate risk to zero, then lock the hangar doors, eat Ryvita and drink tomato juice. 10 years later write a 1 page book on how interesting your life is!
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Mike Flynn,
Perhaps you might provide us a copy of the Risk Assessment Protocol that you are using to predicate your evaluation of the Risks for the Takeoff performed that sad day so that we can all have a better understanding of exactly why you have the opinion you do re that event.
It might prove useful to be able to demonstrate the benefit of the Risk Analysis you do for your own operations and perhaps others might consider incorporating yours into their theirs.
Perhaps you might provide us a copy of the Risk Assessment Protocol that you are using to predicate your evaluation of the Risks for the Takeoff performed that sad day so that we can all have a better understanding of exactly why you have the opinion you do re that event.
It might prove useful to be able to demonstrate the benefit of the Risk Analysis you do for your own operations and perhaps others might consider incorporating yours into their theirs.
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Oh c'mon Mike Flynn....I guess you better give up your car as the chances of an accident and someone being killed are 10,000 fold? Was there really a need for you to pop to the shops that night for a bottle of wine, or get that ever so important takeaway, every journey being a risk to someone? If you go out for a walk do you wear a crash helmet incase of falling debris from an airliner? There was nothing risky about that departure.... just bad luck on the crew. I suggest you light up some candles in your house, and take cold showers, so that the boys and girls don't have to risk their lives going to oil/gas/wind platforms/farms in the N.Sea for our energy needs, as this is way more risky than departing a stadium...just look at the terrible loss of life over the last 20 years..
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Below the Glidepath - not correcting