FAI into Clutha crash opens
Joined: Mar 2005
Aviation Qualifications: Military
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From: Aus
There is a world of difference between a real one (been there, done that) and practising, which is generally not done in twins
Joined: Jul 2001
Aviation Qualifications: ATPL(H)
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From: UK
I think it was addressed. Firstly the (false) expectation that there would be a much longer period between engine flameouts, and secondly that when 500’ agl over a city at night without a radalt or landing light, a successful autorotative landing is highly unlikely in reality. Which is true.
If you would like to demonstrate that you have made a successful engine off landing in a built up area from 500’ at night etc, then I might be persuaded otherwise but failing that, I’m with the sheriff. Those who think they could do it have never tried it..
If you would like to demonstrate that you have made a successful engine off landing in a built up area from 500’ at night etc, then I might be persuaded otherwise but failing that, I’m with the sheriff. Those who think they could do it have never tried it..
My observations from the AAIB report are that the aircraft crashed with zero ground speed and zero rotor RPM. That's quite an achievement from 500(approx) feet agl and about 100kts groundspeed. If the pilot did nothing at all, the aircraft trajectory would still have some forward element would it not?
The report stated that the Low NR warning activated twice, was extinguished twice and then activated a third time and remained on. My hypothesis is that the first warning activated shortly after the second engine failed. The pilots instinctive reaction would be to lower the lever. If there was a restriction and the lever couldn't be lowered fully, only partially, a cyclic flare could recover the NR. This could potentially be achieved a second time but once forward airspeed and hence flare effect is depleted there's no further way to recover NR. This scenario could explain the rotor stall and the lack of ground speed.
Could something as simple as a clipboard or tasking folder have been in exactly the wrong place at the wrong time? I find this more plausible than a pilot of his experience, with heightened awareness after the first engine failure, simply mishandling the autorotation (albeit in exceptionally demanding circumstances).
JJ
Joined: Jan 2006
Posts: 482
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From: 3nm SE of TNT, UK
With regard to Dr Thomas’ statement:
“Distressing” – understandable given her personal loss.
“Incomprehensible” – then she has not been listening.
“given months, not moments” – actually, the Captain of the aircraft had at least 8 minutes of the Low Fuel Sensors telling him to land the aircraft which he acknowledged but failed to act upon.
“history of faults with the Caution Advisory Display” – Not so - the CAD only displays what it is being told to display by the various sensors connected to it. Like any other computer, cr@p in – cr@p out.
“specifically, a history of erroneous or spurious fuel indications, amongst other technical problems such as contamination of the fuel tanks” - correct and still being reported.
Having experienced the phenomena of being told one thing by the display/qty sensors and another by the Low Fuel Sensors in similar circumstances to JT2as far back as 2007 and 2012, it also caused confusion initially but, nevertheless the aircraft was on the ground in very short order. As a result, like JT2, I also spent a day in the witness box at the FAI.
It wasn’t until I was being interviewed by Police Scotland during the evidence gathering process in 2017 that I actually did the maths on this one and it really hammered home the point. For those who haven’t done it yet:
Take off at 2044, crash at 2222 = 98 Minutes.
Fuel indicated at Startup = 400Kgs, Fuel found in wreckage 76Kgs = Fuel used 324Kgs.
EC135 Fuel planning figure 200Kgs per hour/3.33 per minute.
324Kgs used divided by 3.33 = 97.3 minutes.
“Distressing” – understandable given her personal loss.
“Incomprehensible” – then she has not been listening.
“given months, not moments” – actually, the Captain of the aircraft had at least 8 minutes of the Low Fuel Sensors telling him to land the aircraft which he acknowledged but failed to act upon.
“history of faults with the Caution Advisory Display” – Not so - the CAD only displays what it is being told to display by the various sensors connected to it. Like any other computer, cr@p in – cr@p out.
“specifically, a history of erroneous or spurious fuel indications, amongst other technical problems such as contamination of the fuel tanks” - correct and still being reported.
Having experienced the phenomena of being told one thing by the display/qty sensors and another by the Low Fuel Sensors in similar circumstances to JT2as far back as 2007 and 2012, it also caused confusion initially but, nevertheless the aircraft was on the ground in very short order. As a result, like JT2, I also spent a day in the witness box at the FAI.
It wasn’t until I was being interviewed by Police Scotland during the evidence gathering process in 2017 that I actually did the maths on this one and it really hammered home the point. For those who haven’t done it yet:
Take off at 2044, crash at 2222 = 98 Minutes.
Fuel indicated at Startup = 400Kgs, Fuel found in wreckage 76Kgs = Fuel used 324Kgs.
EC135 Fuel planning figure 200Kgs per hour/3.33 per minute.
324Kgs used divided by 3.33 = 97.3 minutes.
Joined: Aug 2000
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From: Liverpool based Geordie, so calm down, calm down kidda!!
Could I request that people take time to read the full report before any further comments on the Sheriff’s conclusion. The press are misrepresenting the gist of his words. What he is saying is not condemnation of Dave. It could have been worded better, but he disagrees with the AAIB to some extent. He believes that Dave’s actions were that of someone being Led/confused by the indication in front of him, leading to him doubting the red warnings and ignoring them. In other words, mitigating circumstances. However Dave’s decision to not believe the warnings was ultimately his decision. He didn’t recklessly accept a new task like the papers are implying, but he did choose to not believe the red warnings. That identification of the mitigation was the best outcome that I could have hoped for. He made an error of judgement, NOT a reckless decision.
Joined: Feb 2006
Posts: 927
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From: Germany
Could I request that people take time to read the full report before any further comments on the Sheriff’s conclusion. The press are misrepresenting the gist of his words. What he is saying is not condemnation of Dave. It could have been worded better, but he disagrees with the AAIB to some extent. He believes that Dave’s actions were that of someone being Led/confused by the indication in front of him, leading to him doubting the red warnings and ignoring them. In other words, mitigating circumstances. However Dave’s decision to not believe the warnings was ultimately his decision. He didn’t recklessly accept a new task like the papers are implying, but he did choose to not believe the red warnings. That identification of the mitigation was the best outcome that I could have hoped for. He made an error of judgement, NOT a reckless decision.
So his view is legit, but we know, that we as aviators can’t follow/understand Dave’s Decision making, especially knowing, that normally every pilot should have a general idea about his endurance.
As the calculations show, a started stopwatch at t/o would have given him the same information as the warnings did, which he ignored.
And getting a fuel warning, you surely check the indications, but also their plausibility against time flown.
There sure was a human factor involved, which isn’t covered, cause we don’t know, what conversation happened in the bird
Joined: Oct 2014
Posts: 174
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From: UK
FB - I'm not sure that's the case. The calculation would have shown him that he had about 75kg left - which he did - the problem is not how much fuel he had (enough for a good twenty minutes) but where it was, ie not in the supply tanks. Or have I misunderstood something?
Joined: Feb 2006
Posts: 927
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From: Germany
Evenso I landed under minimum fuel required (a couple of times), I always had a very close eye, on where my fuel was (balancing it in another ship) to avoid an early flame out.
20 min was less than required for landing by the operator.
Going below minimum fuel can happen in aviation - but I think, a very very good reason is required to accept this extra risk - i.e. a life saving mission.
And when doing so, evaluating the associated risks - and having a plan B, in case of miscalculating the fuel available.
We don´t have the police control information here - but the flight path, hovering here, hovering there, which doesn´t really implement, that they found somebody where the ground forces needed guidons to rescue them.
I know, at the moment I´m more the devils advocate - but thats my point of view.
Joined: Aug 2000
Posts: 2,055
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From: Liverpool based Geordie, so calm down, calm down kidda!!
My ac had 46kg in the tanks. It read 116kg on the gauges.
i was expecting around 120 kg so it all looked ok.
what I DIDNT know was that at the start of the day, my 400kg on the gauges was actually around 320kg in the tanks.
A stopwatch was as much use as tits on a bull
i was expecting around 120 kg so it all looked ok.
what I DIDNT know was that at the start of the day, my 400kg on the gauges was actually around 320kg in the tanks.
A stopwatch was as much use as tits on a bull
Joined: Feb 2001
Posts: 542
Likes: 5
From: Europe
If tanks don’t get topped, run down to a warning light, or even more unlikely drained, one is surely not going to know whether the gauge readings are accurate. I guess in a police role with with heavy loads such a scenario could continue for several weeks and maybe months. Not of course that this should change response to a red low fuel warning.
Last edited by rotorspeed; 6th November 2019 at 21:48.
Joined: Aug 2000
Aviation Qualifications: ATP+Mil
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From: SW England
sycamore, neither would work on a 135 - the filler tube goes through a 90-degree bend; fuel only sits in the upper portion of the filler when the main tank is within 8-10 kg of full, which would never be the case on a UK police operation.
Joined: Dec 2006
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From: UK and MALTA
Starting a stopwatch to calculate your endurance during Police Operations is about as much use as an ashtray on a motorbike!
Hovering, circling, balls-out to the next job. The fuel consumption is up and down like the proverbial whores draws!
Dave Trail deserves better. Like I said earlier. The hill of Hindsight is just that.
Joined: Oct 2006
Posts: 268
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From: Florida
Fly Bull, me thinks there is a lot of "Bull***t" in your statement above.
Starting a stopwatch to calculate your endurance during Police Operations is about as much use as an ashtray on a motorbike!
Hovering, circling, balls-out to the next job. The fuel consumption is up and down like the proverbial whores draws!
Dave Trail deserves better. Like I said earlier. The hill of Hindsight is just that.
Starting a stopwatch to calculate your endurance during Police Operations is about as much use as an ashtray on a motorbike!
Hovering, circling, balls-out to the next job. The fuel consumption is up and down like the proverbial whores draws!
Dave Trail deserves better. Like I said earlier. The hill of Hindsight is just that.
Joined: Oct 1999
Aviation Qualifications: ATPL
Posts: 7,373
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From: Den Haag
I guess it depends on how you define “not to a large degree”. Airbus data online shows about a 35% reduction between cruise and Vy (I.e. cruise will be 50% higher than loiter). The difference between hovering OGE and Vy would be at least as big.
Joined: Feb 2006
Posts: 927
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From: Germany
Fly Bull, me thinks there is a lot of "Bull***t" in your statement above.
Starting a stopwatch to calculate your endurance during Police Operations is about as much use as an ashtray on a motorbike!
Hovering, circling, balls-out to the next job. The fuel consumption is up and down like the proverbial whores draws!
Dave Trail deserves better. Like I said earlier. The hill of Hindsight is just that.
Starting a stopwatch to calculate your endurance during Police Operations is about as much use as an ashtray on a motorbike!
Hovering, circling, balls-out to the next job. The fuel consumption is up and down like the proverbial whores draws!
Dave Trail deserves better. Like I said earlier. The hill of Hindsight is just that.
I have really no clue whatsoever,
with a navy background, some freelancing and flying police ops since the year 2000 ...
with Bo105, BK117 (B2/C1 Variants), EC155, H145.
Hovering, cruising, transporting, loitering...
experiencing different fuel states between hover and cruise, switching pumps.
its standard, that the next mission(s) are given over radio- while on one mission.
may be its due training with the RN, that I do a fuel check before takeoff,
check the burn rate around every 30 min
and have a close eye on in which tank my fuel is.
Canceling warnings without reacting accordingly is just what I can’t understand from an aviator point of view
if that’s „Bull....“ for you, I don’t want to fly with you...
Joined: Aug 2004
Posts: 2,105
Likes: 50
From: Aberdeen
double bogey,
I have really no clue whatsoever,
with a navy background, some freelancing and flying police ops since the year 2000 ...
with Bo105, BK117 (B2/C1 Variants), EC155, H145.
Hovering, cruising, transporting, loitering...
experiencing different fuel states between hover and cruise, switching pumps.
its standard, that the next mission(s) are given over radio- while on one mission.
may be its due training with the RN, that I do a fuel check before takeoff,
check the burn rate around every 30 min
and have a close eye on in which tank my fuel is.
Canceling warnings without reacting accordingly is just what I can’t understand from an aviator point of view
if that’s „Bull....“ for you, I don’t want to fly with you...
Joined: Feb 2006
Posts: 927
Likes: 12
From: Germany
Helicomparator
you haven’t really read my posts, have you?
I wrote, that we don’t have - and I guess won‘t get the information, what was happening inside the bird in regards of communication/ human factors.
I really know, that if the holes start to line up, the risk of desaster increases exponentially.
Thats why you have to back off and re evaluate the situation sensing any hole, may it pressure on the crew, may it be weather, may it be any failure of hardware.
And at the end, decide for the safety of the crew.
With repeating warnings there is no really any reason to continue police work without solving that problem (hole in the cheese) first.
I won’t say, I couldn’t oversee something- which I wrote before, everybody can reach his limits (easily shown in a Sim, if someone doesn’t believe)
But been there I learned a lesson to back off early.
Dave didn’t had the luck.
you haven’t really read my posts, have you?
I wrote, that we don’t have - and I guess won‘t get the information, what was happening inside the bird in regards of communication/ human factors.
I really know, that if the holes start to line up, the risk of desaster increases exponentially.
Thats why you have to back off and re evaluate the situation sensing any hole, may it pressure on the crew, may it be weather, may it be any failure of hardware.
And at the end, decide for the safety of the crew.
With repeating warnings there is no really any reason to continue police work without solving that problem (hole in the cheese) first.
I won’t say, I couldn’t oversee something- which I wrote before, everybody can reach his limits (easily shown in a Sim, if someone doesn’t believe)
But been there I learned a lesson to back off early.
Dave didn’t had the luck.