Police helicopter crashes onto Glasgow pub: final AAIB report
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GOULI good post!
I suggest a quick reading of Thinking Fast, Thinking Slow by Daniel Kannerham (not sure spelling).
Human Factors was clearly a causal part of this accident - it almost always is. To suggest that excuses design gotchas, training shortcomings, whatever...is absurd and practically medieval.
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I'm disappointed somewhat :-(
So because the pilot DISMISSED the Low Fuel Warnings, it seems as though some on this forum don't believe that the pilot deserved to have had the benefit of:
Prior knowledge of this type of fault? - In the last few days a previous poster has informed that GXMII had a similar fault to GNWEM but way back in 2004/2005. I'm shocked, because if the pilot of GSPAO had this knowledge, I really don't believe that he would have dismissed the Low Fuel Warnings. This knowledge comes from Pilots, (reporting exact fault, relaying their concerns of the implications of a particular fault based on their flying knowledge), Engineers (Fault finding and reporting), Operators (Investigation, Information sharing, Consulting with Manufacturers), Manufacturers (flight testing, what possible effects could this fault have, is redesign necessary) etc. So yes, the aviation community as a whole has let this crew down.
because this pilot dismissed the Low Fuel Warnings, you think he subsequently didn't deserve to have had his:
4 minutes designed time between engine failures due to fuel starvation? I was trained that I had 4 minutes between failures due to fuel starvation, but we now know otherwise. The outcome would have been very different with 4 minutes OEI. The aviation community has worked together post accident in realising that time between failures is only 30 Seconds ish. But there is more work to be done, we want 4 minutes. So elements of the aviation community have let them down right at the start. What will this customer use my product for, do we need to test it, is it still fit for purpose, could we make it safer still? Some of the fuel flowover information we now have is fairly basic stuff, surely the 4 minutes between flame outs was proved with a few tests, not just straight and level?
......and because the pilot dismissed the Low Fuel warnings, you find it easier to accuse him of:
botching (to carry out a task badly or carelessly) the autorotation? - I agree that the autorotation did not have a successful outcome, and I'm not sure if I would have done any better quite honestly. Does that mean he did it carelessly, or might it be that it was a really very difficult, even for such an experienced aviator? Or could there be other contributory issues, which we might otherwise ignore if we just think he was careless? Early signs of managing NR control were clearly evident, so if he was completely careless there would have only been one Low RPM Warning! But the autorotation would certainly be more difficult to judge at Night, with buildings, Obstructions, Inadequate time and capacity to reach the shed bus (if he had reached shed bus - how long does it take for the rad alt to come on line anyway?), a possible Batt Discharge Gong with a sound exactly the same as NR rising through 106%. I think 'botched' is just a little unfair and disrespectful. So the aviation community need to look a bit more at this aspect. Do we need more training? Do we need auto switch for Landing Lamp and Rad Alt etc. Why haven't we thought about this before - was it too expensive to modify, too difficult?
And finally, because the pilot dismissed the Low Fuel Warnings, you think he doesn't deserve to have had the flight trials (AAIB and Manufacturer) at Dalkeith show that it is possible to get a F PUMP FWD caution due to dry running at a slower airspeed? This simple puts doubt in readers minds, right at the beginning of the report. Also, why can't the general public be presented with a possible scenario like mine which is fairly obvious? This at least uses the AAIBs knowledge of potential faults and demonstrates that the pilot might not have had a FUEL caution to ignore, or supply tank fuel level graphics to ignore etc at the point of dismissing the Low Fuel Warnings.
So, yes I do think the aviation community at all levels has let them down.
Prior knowledge of this type of fault? - In the last few days a previous poster has informed that GXMII had a similar fault to GNWEM but way back in 2004/2005. I'm shocked, because if the pilot of GSPAO had this knowledge, I really don't believe that he would have dismissed the Low Fuel Warnings. This knowledge comes from Pilots, (reporting exact fault, relaying their concerns of the implications of a particular fault based on their flying knowledge), Engineers (Fault finding and reporting), Operators (Investigation, Information sharing, Consulting with Manufacturers), Manufacturers (flight testing, what possible effects could this fault have, is redesign necessary) etc. So yes, the aviation community as a whole has let this crew down.
because this pilot dismissed the Low Fuel Warnings, you think he subsequently didn't deserve to have had his:
4 minutes designed time between engine failures due to fuel starvation? I was trained that I had 4 minutes between failures due to fuel starvation, but we now know otherwise. The outcome would have been very different with 4 minutes OEI. The aviation community has worked together post accident in realising that time between failures is only 30 Seconds ish. But there is more work to be done, we want 4 minutes. So elements of the aviation community have let them down right at the start. What will this customer use my product for, do we need to test it, is it still fit for purpose, could we make it safer still? Some of the fuel flowover information we now have is fairly basic stuff, surely the 4 minutes between flame outs was proved with a few tests, not just straight and level?
......and because the pilot dismissed the Low Fuel warnings, you find it easier to accuse him of:
botching (to carry out a task badly or carelessly) the autorotation? - I agree that the autorotation did not have a successful outcome, and I'm not sure if I would have done any better quite honestly. Does that mean he did it carelessly, or might it be that it was a really very difficult, even for such an experienced aviator? Or could there be other contributory issues, which we might otherwise ignore if we just think he was careless? Early signs of managing NR control were clearly evident, so if he was completely careless there would have only been one Low RPM Warning! But the autorotation would certainly be more difficult to judge at Night, with buildings, Obstructions, Inadequate time and capacity to reach the shed bus (if he had reached shed bus - how long does it take for the rad alt to come on line anyway?), a possible Batt Discharge Gong with a sound exactly the same as NR rising through 106%. I think 'botched' is just a little unfair and disrespectful. So the aviation community need to look a bit more at this aspect. Do we need more training? Do we need auto switch for Landing Lamp and Rad Alt etc. Why haven't we thought about this before - was it too expensive to modify, too difficult?
And finally, because the pilot dismissed the Low Fuel Warnings, you think he doesn't deserve to have had the flight trials (AAIB and Manufacturer) at Dalkeith show that it is possible to get a F PUMP FWD caution due to dry running at a slower airspeed? This simple puts doubt in readers minds, right at the beginning of the report. Also, why can't the general public be presented with a possible scenario like mine which is fairly obvious? This at least uses the AAIBs knowledge of potential faults and demonstrates that the pilot might not have had a FUEL caution to ignore, or supply tank fuel level graphics to ignore etc at the point of dismissing the Low Fuel Warnings.
So, yes I do think the aviation community at all levels has let them down.
Last edited by 8Pieced; 9th Nov 2015 at 09:24. Reason: flowover not flow over
Purveyor of Egg Liqueur to Lucifer
Ok thanks Gouli, happy to explain that;
I 'recently' saw a report about a crash at a motorway toll booth where a vehicle ran into the back of another that was waiting to pay at the booth. The defence case was that the person driving the moving vehicle braked but nothing happened. It went to forensics to find out if she had in fact braked or not … she had, the brake lights were on for a period of time before impact with was also backed up by CCTV. I think this led to a recall for the car type due to a brake problem.
My point;
As you highlight from page 58;
But what did we really need to know about the lamps?
Lamp Examination to Determine On or Off in a Collision
http://www.harristechnical.com/articles/lamp.pdf
So, I now hear DB asking, 'with no visual or audio warnings presenting themselves, how was it that they were acknowledged?'
Well perhaps it was the action of the Fuel caution being cancelled that also cancelled those Low Fuel warnings, there's no time line to say how long the warning lights were on for before acknowledgement.
Now, this was a manufacturers test of the warning unit and they were probably tasked to determine if the system was functioning correctly and not necessarily whether the lamps were on at the time, or not. If a filament examination did take place to determine whether the lights were on for such a long time before impact (15 mins), it isn't in the report.
Which then leads us down the path as to why/how it was that the warning light went out when the warning was acknowledged, because surely the fuel level in supply tank 1 was still low after the acknowledgement because if you believe what DB tells us, you can't gain fuel.
I 'recently' saw a report about a crash at a motorway toll booth where a vehicle ran into the back of another that was waiting to pay at the booth. The defence case was that the person driving the moving vehicle braked but nothing happened. It went to forensics to find out if she had in fact braked or not … she had, the brake lights were on for a period of time before impact with was also backed up by CCTV. I think this led to a recall for the car type due to a brake problem.
My point;
As you highlight from page 58;
Warning unit testing
Testing of the warning unit at the manufacturer’s facility showed that all the indicator lamps operated correctly, using both the bright and dimmed settings.
Initially, the unit drew more current than normal and did not generate the required audio attention-getters associated with the visual warnings. After a few minutes of testing, one of the tantalum capacitors, connected across the power supply of the audio amplifier, partially disintegrated. Subsequently, the current used by the unit returned to normal and the audio attention-gettersoperated correctly.
Testing of the warning unit at the manufacturer’s facility showed that all the indicator lamps operated correctly, using both the bright and dimmed settings.
Initially, the unit drew more current than normal and did not generate the required audio attention-getters associated with the visual warnings. After a few minutes of testing, one of the tantalum capacitors, connected across the power supply of the audio amplifier, partially disintegrated. Subsequently, the current used by the unit returned to normal and the audio attention-gettersoperated correctly.
But what did we really need to know about the lamps?
Lamp Examination to Determine On or Off in a Collision
http://www.harristechnical.com/articles/lamp.pdf
"Do not, under any circumstances, turn on a vehicle's lights after an accident in an attempt to determine if they were functional at the time of the collision. This one act may very well destroy the evidence you are seeking.
.
.
In a lamp with two filaments, if one is incandescent, the hotter of the two will deform more than the other. "
.
.
In a lamp with two filaments, if one is incandescent, the hotter of the two will deform more than the other. "
So, I now hear DB asking, 'with no visual or audio warnings presenting themselves, how was it that they were acknowledged?'
Well perhaps it was the action of the Fuel caution being cancelled that also cancelled those Low Fuel warnings, there's no time line to say how long the warning lights were on for before acknowledgement.
Now, this was a manufacturers test of the warning unit and they were probably tasked to determine if the system was functioning correctly and not necessarily whether the lamps were on at the time, or not. If a filament examination did take place to determine whether the lights were on for such a long time before impact (15 mins), it isn't in the report.
Which then leads us down the path as to why/how it was that the warning light went out when the warning was acknowledged, because surely the fuel level in supply tank 1 was still low after the acknowledgement because if you believe what DB tells us, you can't gain fuel.
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The red light comes on - land, don't accept another tasking.
If he had taken your advice he would have made at least 5 precautionary landings on this sortie alone. Madness.
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Well said Sky 
Don't forget that the cards say;
If the Fuel Low warning light remains ON
Bleed Air Switch - Off
Land within 10 mins
Didn't DB also tell us;
"Above all Sid the lesson here is that none of us should try routinely to second guess the FM Emergency Responses. If the pilot followed the requirements of the FM that night he should have RTBed at the first Low Fuel Caption. "
Makes me wonder which report he is reading.
Gouli;
The red light comes on - land, don't accept another tasking.
The red light comes on - land, don't accept another tasking.
Don't forget that the cards say;
If the Fuel Low warning light remains ON
Bleed Air Switch - Off
Land within 10 mins
Didn't DB also tell us;
"Above all Sid the lesson here is that none of us should try routinely to second guess the FM Emergency Responses. If the pilot followed the requirements of the FM that night he should have RTBed at the first Low Fuel Caption. "
Makes me wonder which report he is reading.
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I think the complexity of modern aircraft has resulted in a situation where pilots no longer have a complete understanding of all the interactions between the various components. Even the manufacturers get the design wrong or make assumptions about how the aircraft will be flown.
The twin supply tanks were designed to give four minutes extra duration when the smaller tank ran dry, allowing a single engine landing. No account was taken of the direction that a helicopter might be flying an orbit and that the tanks might not drain symmetrically.
Modern appliances in general have become so complex that we have no choice but to follow the manufacturers advice as to how to get best use from them. That applies to aircraft, cars, computers, domestic appliances and all manner of other gadgets.
Older pilots will be highly suspicious of relying so much on technology, young pilots just go with the flow and accept all the help automation offers. I would suggest that the cross over pilots who learned to fly using manual methods and who were then effectively forced to adapt to automation are those most at risk of having an accident due to not following the manufacturers guidelines.
They have sufficient experience to know when a cockpit indication might be spurious and have previously demonstrated the ability to fly without all the automated assistance. So they are more likely to be complacent in their ability to handle things if and when they go wrong. But the complexity of modern aircraft means that the pilot's complacency is plain wrong and not everything works how it should given their previous knowledge and experience.
The roll out of advanced safety equipment in cars hasn't significantly reduced the overall accident rate, but it has done a great deal to mitigate the consequences of a collision. Older drivers frequently mistrust and are confused by all the options available, but the younger computer generation just accept that is how cars are. Every weekend used to be occupied with car maintenance of some sort but now the car gets taken to the garage once a year for a service and MoT and no one has any idea how it all works. How did VW get away with their emissions fiddling for so long?
The design of the EC135 fuel system is typical of the current practice of introducing too much complexity. If you want to get every last drop of fuel out of a tank, use a flexible hose with a big brass nut on the end to weigh it down. It draws fuel from the lowest point of the tank no matter what the orientation of the aircraft. Make switches in different shapes and colours for different functions. The most aesthetically pleasing visual designs are often the least functional to ise in an emergency situation.
The AAIB report also makes clear that the manufacturer assumes that the radio altimeter and landing light will be available for autorotation, except you need to turn and operate the shed bus switch to activate them when both generators fail. Virtually impossible!
Another big gotcha is the rotor overspeed alarm sounding in an autorotative state. So what if the rotor rpm exceeds 106%? The more rotor rpm the better, so long as it doesn't fly apart. It isn't like you are going to be flying away any time soon after a dual engine failure and autorotation to the ground.
There have been a great many failings all around from the designers through to the writers of the operators manual, all indicative that no one person understood all the aspects of the design. But the bottom line is that it is the pilot who carries the blame when it all goes tragically wrong.
Stereotyping and over simplification is just my lazy way of avoiding typing several pages of post. It doesn't mean I haven't read the text books or lack understanding of human factors, design or engineering. I have worked part time as a diagnostic engineer over many years and investigated numerous accidents, but only took part in one aviation one.
The twin supply tanks were designed to give four minutes extra duration when the smaller tank ran dry, allowing a single engine landing. No account was taken of the direction that a helicopter might be flying an orbit and that the tanks might not drain symmetrically.
Modern appliances in general have become so complex that we have no choice but to follow the manufacturers advice as to how to get best use from them. That applies to aircraft, cars, computers, domestic appliances and all manner of other gadgets.
Older pilots will be highly suspicious of relying so much on technology, young pilots just go with the flow and accept all the help automation offers. I would suggest that the cross over pilots who learned to fly using manual methods and who were then effectively forced to adapt to automation are those most at risk of having an accident due to not following the manufacturers guidelines.
They have sufficient experience to know when a cockpit indication might be spurious and have previously demonstrated the ability to fly without all the automated assistance. So they are more likely to be complacent in their ability to handle things if and when they go wrong. But the complexity of modern aircraft means that the pilot's complacency is plain wrong and not everything works how it should given their previous knowledge and experience.
The roll out of advanced safety equipment in cars hasn't significantly reduced the overall accident rate, but it has done a great deal to mitigate the consequences of a collision. Older drivers frequently mistrust and are confused by all the options available, but the younger computer generation just accept that is how cars are. Every weekend used to be occupied with car maintenance of some sort but now the car gets taken to the garage once a year for a service and MoT and no one has any idea how it all works. How did VW get away with their emissions fiddling for so long?
The design of the EC135 fuel system is typical of the current practice of introducing too much complexity. If you want to get every last drop of fuel out of a tank, use a flexible hose with a big brass nut on the end to weigh it down. It draws fuel from the lowest point of the tank no matter what the orientation of the aircraft. Make switches in different shapes and colours for different functions. The most aesthetically pleasing visual designs are often the least functional to ise in an emergency situation.
The AAIB report also makes clear that the manufacturer assumes that the radio altimeter and landing light will be available for autorotation, except you need to turn and operate the shed bus switch to activate them when both generators fail. Virtually impossible!
Another big gotcha is the rotor overspeed alarm sounding in an autorotative state. So what if the rotor rpm exceeds 106%? The more rotor rpm the better, so long as it doesn't fly apart. It isn't like you are going to be flying away any time soon after a dual engine failure and autorotation to the ground.
There have been a great many failings all around from the designers through to the writers of the operators manual, all indicative that no one person understood all the aspects of the design. But the bottom line is that it is the pilot who carries the blame when it all goes tragically wrong.
Stereotyping and over simplification is just my lazy way of avoiding typing several pages of post. It doesn't mean I haven't read the text books or lack understanding of human factors, design or engineering. I have worked part time as a diagnostic engineer over many years and investigated numerous accidents, but only took part in one aviation one.
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8P
I can answer this…. It's a twin and twins never have double engine failure and can continue on one.
Do we need auto switch for Landing Lamp and Rad Alt etc. Why haven't we thought about this before - was it too expensive to modify, too difficult?
The AAIB report also makes clear that the manufacturer assumes that the radio altimeter and landing light will be available for autorotation, except you need to turn and operate the shed bus switch to activate them when both generators fail
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skyrangerpro
If he had taken my advice he would have made only the one precautionary landing and the crew would in all likelyhood have been alive to walk away from it. Subsequent preparation for takeoff would have revealed the supply tank switches in the wrong position, so again the accident would have been avoided.
There would have been considerable embarrassment and no doubt strong words without tea and biscuits back at the office, but the crew would be alive and the helicopter still flying.
It is amazing just how often embarrassment (or trying to avoid it) ends up killing people.
If he had taken my advice he would have made only the one precautionary landing and the crew would in all likelyhood have been alive to walk away from it. Subsequent preparation for takeoff would have revealed the supply tank switches in the wrong position, so again the accident would have been avoided.
There would have been considerable embarrassment and no doubt strong words without tea and biscuits back at the office, but the crew would be alive and the helicopter still flying.
It is amazing just how often embarrassment (or trying to avoid it) ends up killing people.
Purveyor of Egg Liqueur to Lucifer
Do we need auto switch for Landing Lamp and Rad Alt etc. Why haven't we thought about this before - was it too expensive to modify, too difficult?
chopjock;
I can answer this…. It's a twin and twins never have double engine failure and can continue on one.
I can answer this…. It's a twin and twins never have double engine failure and can continue on one.
Purveyor of Egg Liqueur to Lucifer
In light of this, have any operators resorted to flying with the shed bus switch in 'override', at night?
Mind you I can only just fathom out the HiFi Amp in/out leads, so I'm no great master of wiring diagrams!
Gouli, you're absolutely right about landing when that first red warning came on and it's something I think we shall all be doing should it happen to us. The cards still tell us it's ok to carry on if the light goes out, or if it stays on you have 10 mins. Unfortunately, on that night hindsight (or the passage of info) wasn't available to them
It is amazing just how often embarrassment (or trying to avoid it) ends up killing people.
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Sid;
A good few years ago we re-wrote our company checklists for cleaning up after a single engine **** down. The final item is "Open Bus Shed Switch"
From a company point of view this is because we fly them a lot at night or IFR, single pilot, and as you know, trying to find that switch in auto on an OPC is hard enough, for real IMC or night would probably distract too much from the auto.
SND
A good few years ago we re-wrote our company checklists for cleaning up after a single engine **** down. The final item is "Open Bus Shed Switch"
From a company point of view this is because we fly them a lot at night or IFR, single pilot, and as you know, trying to find that switch in auto on an OPC is hard enough, for real IMC or night would probably distract too much from the auto.
SND
Purveyor of Egg Liqueur to Lucifer
That makes sense SND, especially as with a single engine shutdown/failure/gen failure all the demand from the role equipment would be automatically lost. Therefore the loading from the battery wouldn't be so great once the Shed Bus is switched and it would only be open for a short time.
However, how would the system stand with the Shed Bus open for hours at a time?
As I say, I'm no wiring guru so my interpretation of the battery load may well be incorrect.
Makes you wonder; if one company is doing this, why hasn't word got round?
However, how would the system stand with the Shed Bus open for hours at a time?
As I say, I'm no wiring guru so my interpretation of the battery load may well be incorrect.
Makes you wonder; if one company is doing this, why hasn't word got round?
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I still think it has more to do with the faulty capacitor - drawing too much current and clobbering other systems.
I'll say it again, tantalum capacitors aren't usually damaged by g forces, they are solid in design and not filled with electrolyte... Plus the report says the wrong voltage one was fitted, it however doesn't say if the working voltage was either higher or lower - which I'd like to know.
Anybody got access to a circuit diagram?
Kev.
I'll say it again, tantalum capacitors aren't usually damaged by g forces, they are solid in design and not filled with electrolyte... Plus the report says the wrong voltage one was fitted, it however doesn't say if the working voltage was either higher or lower - which I'd like to know.
Anybody got access to a circuit diagram?
Kev.
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Work arounds!!
Here we go again, already talking about work arounds to something not quite right. This one thoroughly now well understood due to the accident.
With the shed bus to emergency position, are we then more likely to damage other systems with electrical malfunctions? Yes it would be against RFM normal procedure, hence emergency position.
It needs looking at by the manufacturers, proper safe solution. On that night it might have helped them, or still possibly not?? Who knows??
With the shed bus to emergency position, are we then more likely to damage other systems with electrical malfunctions? Yes it would be against RFM normal procedure, hence emergency position.
It needs looking at by the manufacturers, proper safe solution. On that night it might have helped them, or still possibly not?? Who knows??
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Kevin
The report states that it was believed that the performance of the tantalum capacitor was compromised by g forces in the crash. Tantalum capacitors are constructed to fine tolerances using extremely thin insulating layers between the plates. A heavy shock can crack one or more of the internal insulators and allow the capacitor to partially conduct electricity, causing heating of the component. If too much current leaks, the build up of heat will cause the tantalum capacitor to rupture, the exact failure mechanism observed in testing.
The report states that the tantalum capacitor was being operated outside of the range recommended by the manufacturer for that application, not that an incorrect value component was fitted. The design of the circuit board may have dictated that a smaller, less than ideally robust component was fitted due to space constraints, but there is no suggestion that the design was flawed and didn't work correctly. Tantalum capacitors are low voltage components anyway, so it may just have been a case of the capacitor operating at the upper edge of its design voltage with no headroom in case of faults or voltage spikes elsewhere in the circuit.
Electronic design is a series of compromises where the ideal component values are replaced by what is available on the market and what fits the circuit board. No different to compromises made in other areas of engineering. Capacitors generally are among the least accurate and most troublesome electronic components, so it might make more sense to fit overrated components in critical circuit areas. I suspect this is what the investigators meant by their comment.
The report states that it was believed that the performance of the tantalum capacitor was compromised by g forces in the crash. Tantalum capacitors are constructed to fine tolerances using extremely thin insulating layers between the plates. A heavy shock can crack one or more of the internal insulators and allow the capacitor to partially conduct electricity, causing heating of the component. If too much current leaks, the build up of heat will cause the tantalum capacitor to rupture, the exact failure mechanism observed in testing.
The report states that the tantalum capacitor was being operated outside of the range recommended by the manufacturer for that application, not that an incorrect value component was fitted. The design of the circuit board may have dictated that a smaller, less than ideally robust component was fitted due to space constraints, but there is no suggestion that the design was flawed and didn't work correctly. Tantalum capacitors are low voltage components anyway, so it may just have been a case of the capacitor operating at the upper edge of its design voltage with no headroom in case of faults or voltage spikes elsewhere in the circuit.
Electronic design is a series of compromises where the ideal component values are replaced by what is available on the market and what fits the circuit board. No different to compromises made in other areas of engineering. Capacitors generally are among the least accurate and most troublesome electronic components, so it might make more sense to fit overrated components in critical circuit areas. I suspect this is what the investigators meant by their comment.
At night, engaging in a high priority surveillance task the workload can be high.
Non urban routes can be difficult for ground units - too easy to get clocked, hence the eye in the sky.
Not easy for the pilot. Eyes glued to the target - two tail lights among others. Unlike daylight, normally no landmarks relative to the target to help re-identification after a quick cockpit check.
Other front seat occupant busy tracking with the camera, easier now that there's automatic hold on the target, but still must be constantly eyeballed. Back seat busy with map reading and comms.
Target peels off into built up area, time for ground units to take over. Eyes off those tail lights for a couple of seconds and the pilot's lost it. Many red lights all travelling at same speed. V difficult to relate target's position on the tracking camera with what's down there. Workload now intense. Orbit and search. Orbit and look. Need to info ground units of location. Routine calls to air traffic as the ungodly now monitor ATC frequencies when there could be someone up there.
Just a thought .........
Non urban routes can be difficult for ground units - too easy to get clocked, hence the eye in the sky.
Not easy for the pilot. Eyes glued to the target - two tail lights among others. Unlike daylight, normally no landmarks relative to the target to help re-identification after a quick cockpit check.
Other front seat occupant busy tracking with the camera, easier now that there's automatic hold on the target, but still must be constantly eyeballed. Back seat busy with map reading and comms.
Target peels off into built up area, time for ground units to take over. Eyes off those tail lights for a couple of seconds and the pilot's lost it. Many red lights all travelling at same speed. V difficult to relate target's position on the tracking camera with what's down there. Workload now intense. Orbit and search. Orbit and look. Need to info ground units of location. Routine calls to air traffic as the ungodly now monitor ATC frequencies when there could be someone up there.
Just a thought .........
Perhaps - perhaps not, but the AAIB doesn't tell us
At night, engaging in a high priority surveillance task the workload can be high.
Non urban routes can be difficult for ground units - too easy to get clocked, hence the eye in the sky.
Not easy for the pilot. Eyes glued to the target - two tail lights among others. Unlike daylight, normally no landmarks relative to the target to help re-identification after a quick cockpit check.
Other front seat occupant busy tracking with the camera, easier now that there's automatic hold on the target, but still must be constantly eyeballed. Back seat busy with map reading and comms.
Target peels off into built up area, time for ground units to take over. Eyes off those tail lights for a couple of seconds and the pilot's lost it. Many red lights all travelling at same speed. V difficult to relate target's position on the tracking camera with what's down there. Workload now intense. Orbit and search. Orbit and look. Need to info ground units of location. Routine calls to air traffic as the ungodly now monitor ATC frequencies when there could be someone up there.
Just a thought .........
Non urban routes can be difficult for ground units - too easy to get clocked, hence the eye in the sky.
Not easy for the pilot. Eyes glued to the target - two tail lights among others. Unlike daylight, normally no landmarks relative to the target to help re-identification after a quick cockpit check.
Other front seat occupant busy tracking with the camera, easier now that there's automatic hold on the target, but still must be constantly eyeballed. Back seat busy with map reading and comms.
Target peels off into built up area, time for ground units to take over. Eyes off those tail lights for a couple of seconds and the pilot's lost it. Many red lights all travelling at same speed. V difficult to relate target's position on the tracking camera with what's down there. Workload now intense. Orbit and search. Orbit and look. Need to info ground units of location. Routine calls to air traffic as the ungodly now monitor ATC frequencies when there could be someone up there.
Just a thought .........
The pilot's primary job is to keep the aircraft safe, right ?
And in doing this job, the pilot should be somewhat isolated from the mission. It's not like they're trying to stop someone nuking Glasgow. They're not equipped for that anyway.
The ergonomics may not be ideal, but neither are the ergonomics of a 737 plank - have a look at the pilots' comments about them. Should we ground 737s ?
As has been pointed out earlier, other countries law enforcement services have operated EC135s for some time without running out of fuel and then unsurprisingly failing to auto in difficult conditions.
It's not about blame. It's about learning. It seems to me that most of what needs to be learned here is about human factors - which the AAIB fail to adequately address.